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SpaceX Vehicles and Missions => SpaceX Early Days Archive Section => Topic started by: Chris Bergin on 12/30/2015 11:56 am

Title: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Chris Bergin on 12/30/2015 11:56 am
Thread 4 for Falcon Heavy as we head into the year she should debut.

Thread 1:
http://forum.nasaspaceflight.com/index.php?topic=32528.0

Thread 2:
http://forum.nasaspaceflight.com/index.php?topic=35365.0

Thread 3:
http://forum.nasaspaceflight.com/index.php?topic=36806.0

Main FH Articles:
http://www.nasaspaceflight.com/2011/04/spacex-falcon-heavy-tag-team-share-20-launches-year/

http://www.nasaspaceflight.com/2013/05/from-atlas-v-falcon-xx-commercial-suitors-wanted-pad-39a/

http://www.nasaspaceflight.com/2014/07/spacex-roadmap-rocket-business-revolution/

http://www.nasaspaceflight.com/2014/11/pad-39a-spacex-groundwork-falcon-heavy-debut/

http://www.nasaspaceflight.com/2015/05/falcon-heavy-dragon-solar-system-explorer/

http://www.nasaspaceflight.com/2015/10/canaveral-ksc-pads-new-designs-space-access/

http://www.nasaspaceflight.com/2015/11/spacex-conducts-rollout-39a-te/


SpaceX news articles on this site:
Old: http://forum.nasaspaceflight.com/index.php?topic=21862.0 (links)

Then recent news articles, not linked above, as we moved to a tag group system:
All recent: http://www.nasaspaceflight.com/tag/spacex/


L2 SpaceX - Dedicated all-vehicle section - including a mass of new amazing renderings we've created.
http://forum.nasaspaceflight.com/index.php?board=60.0


NOTE: Posts that are uncivil (which is very rare for this forum), off topic (not so rare) or just pointless will be deleted without notice.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rocx on 12/30/2015 12:09 pm
the year she should debut
We are in 2015 already, Chris. Or was that 2014? No wait, I guess the first announced launch date for Falcon Heavy was 2013: http://spacelaunchreport.com/falconH.html.

Anyway, what use is 53 metric tons of payload capacity to LEO? It's not even enough to lift an M1 Abrams, which weighs 54 tons! https://en.wikipedia.org/wiki/M1_Abrams
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rliebman on 12/30/2015 12:46 pm
That would certainly take space warfare to a different level
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Bargemanos on 12/30/2015 02:06 pm
the year she should debut
We are in 2015 already, Chris. Or was that 2014? No wait, I guess the first announced launch date for Falcon Heavy was 2013: http://spacelaunchreport.com/falconH.html (http://spacelaunchreport.com/falconH.html).

Anyway, what use is 53 metric tons of payload capacity to LEO? It's not even enough to lift an M1 Abrams, which weighs 54 tons! https://en.wikipedia.org/wiki/M1_Abrams (https://en.wikipedia.org/wiki/M1_Abrams)

Where do you need a battle tank in space for?

The Kibo module, the largest single module of the ISS is ~16 metric tons.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: clongton on 12/30/2015 02:08 pm
Anyway, what use is 53 metric tons of payload capacity to LEO?

The average mass of most of the ISS modules was <20 tons. I'd say that 53 tons is quite useful.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: yokem55 on 12/30/2015 02:16 pm
How close to the cross-fed enabled 53mt payload to LEO is the non-cross-fed fully expended full thrust falcon heavy? I'm guessing it's fairly close...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rpapo on 12/30/2015 02:25 pm
Anyway, what use is 53 metric tons of payload capacity to LEO?

The average mass of most of the ISS modules was <20 tons. I'd say that 53 tons is quite useful.
There is one minor problem with that (the less than 20 tons part): with the exception of the original Russian modules (Zarya & Svezda), none of the other ISS modules have had propulsion of their own.  Without the Space Shuttle, any new modules will require a tug or their own propulsion in order to rendezvous with the ISS.  The hardware and fuel required costs weight.

Even so, 53 metric tons is about three times the weight of any single module currently attached to the ISS.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rocx on 12/30/2015 02:30 pm
How close to the cross-fed enabled 53mt payload to LEO is the non-cross-fed fully expended full thrust falcon heavy? I'm guessing it's fairly close...
According to Ed Kyle's site (http://spacelaunchreport.com/falconH.html) it will be 45 tons to LEO from Cape Canaveral. That's not even one T-90 (https://en.wikipedia.org/wiki/T-90).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 12/30/2015 02:53 pm
What does a Bigelow 330 module weigh?  If FH can get these to LEO, 2-4 of these would be as large as ISS at a lot less expensive cost than ISS was.  Army tanks won't be used in space.  Way too heavy.  Can't fire the cannon as the opposite reaction would take one out of it's intended orbit. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 12/30/2015 03:07 pm
What does a Bigelow 330 module weigh?  If FH can get these to LEO, 2-4 of these would be as large as ISS at a lot less expensive cost than ISS was.  Army tanks won't be used in space.  Way too heavy.  Can't fire the cannon as the opposite reaction would take one out of it's intended orbit.

The module is listed around 20mT. (Fully reusable FH will easily deliver a BA-330.)
Should think of the FH LEO capability in terms of propellant... this is where launch rate and payload capability will be most impactful.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: punder on 12/30/2015 03:15 pm
How many solid plutonium unicorns can FH put in orbit? In other words, can we stop this tank BS right here, please?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 12/30/2015 04:10 pm
AIUI, the FT+Densification would enable FH to hit the performance numbers without cross feeding. But this is an estimation. In any case the real metric would be 6.5tonnes to a 1,500m/s GTO with full booster and core recovery.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: llanitedave on 12/30/2015 05:27 pm
The LEO standard is not really ISS elevation anyway.  It's not really that useful a metric.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Comga on 12/30/2015 05:47 pm
The LEO standard is not really ISS elevation anyway.  It's not really that useful a metric.

Agreed
One might want to start with the BEO habitat studies. (http://forum.nasaspaceflight.com/index.php?topic=38818.msg1445832#msg1445832).

(Thank you, llanitedave, for bringing this thread back from the realm of gibberish.  Please, people, take the goofy stuff to the party threads.)

PS The first reference for the Falcon 9 Heavy on my list was posted in February of 2011 for launch in late 2012.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 12/30/2015 06:40 pm
Both personally and in the grand scheme I couldn't care less when FH was "supposed" to fly. It's clear that the F9-FT and all its subsequent enhancements leading to a successful RTF & landing , is now in a much better position to transition into a 3 core FH-FT.

By the time FH launches, they'll most likely have returned and inspected a few more cores feeding even more data back into F9/FT and subsequent FH. A reusable F9 is one thing, with the ability to return all 3 cores of FH or even just the boosters, giving them a partially reusable Heavy Lift to LEO will be quite disruptive. IMO.

Specifically disruptive to Human BEO exploration plans.  Scimemi, the ISS director for NASA, says he wants to build the HAB Congress just directed NASA to study and have a prototype ready for 2018. Why would we do that, when for a fraction of the cost, we could send up a prototype BA330 on a FH? (that's a rhetorical question)

FH is still theoretical to most people. But once she launches and those cores return, the very real and enabling contributions for cost-effective Human BEO exploration will be unavoidable. I'm an SLS supporter but to think FH will not have a place to further advance NASA's BEO goals, is to deny the inevitable.

The battle lines within NASA, its' centers, its' current Primes and corresponding Congressional districts will be drawn in even starker relief. I do not think I am overstating the impact this system will have when successfully brought on-line.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 12/30/2015 06:55 pm
I think it's going to be 18+ months till we start to see how much the FH can benefit SpaceX.  They need to develop the F9 reuse and apply that to FH.  And then seeing how the FH can provide the large comsat market. 

None of this is a given and anyone that says they know the economics of a fully reuseable FH doing the same work as expendable F9 is using is making to many assumptions to know for sure.

It's going to be exciting to see develop.  That's the most interesting part of SpaceX.  We get to see the their incremental and real time development.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 12/30/2015 07:21 pm
[...]
Specifically disruptive to Human BEO exploration plans.  Scimemi, the ISS director for NASA, says he wants to build the HAB Congress just directed NASA to study and have a prototype ready for 2018. Why would we do that, when for a fraction of the cost, we could send up a prototype BA330 on a FH? (that's a rhetorical question)
[...]
A Hab would really have to be tested in EML1/2 space. LEO is very different from deep space. For example, you have 45min of hotness and 45min of coldness. In deep space you have a hot side and a cold side, permanently. So the thermal environment is completely different. You have to worry about MMOD and free oxygen in LEO which are not an issue in deep space. You have a lot less radiation, which you actually want to prove the hab design. You need completely different comm system. And a long list of requirements.
Why I'm saying this? Because for such an Hab, unless you are also including a SEP tug (which has no budget), you are going to worry about the C3=-1km˛/s˛ performance. How much could the Falcon Heavy do? If it can, in fact, do 13 to TMI, then it should be able to do between 17 and 20 tonnes to TLI. The problem is, SLS can do something like 45tonnes with EUS and well more than 25 tonnes with the ICPS. So the prototype would have to have less than half the mass of the final hab if it were to fit into a FH.
And I didn't get into the fact that SLS will have an 8.4m fairing (7.5m internal) vs the 5.2m (4.7 internal) of the FH. I rather see FH as an opportunity to send something commercial to LEO very cheaply or a Cygnus derived module to TLI, rather than the full Hab.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: vulture4 on 12/30/2015 08:14 pm
I have difficulty understanding the need for a habitat to be launched directly into a lunar or Mars trajectory. Earth orbit rendezvous (as originally proposed by von Braun) for refueling or mating a departure stage could be used at lower cost. Wasn't that even the original plan for Constellation? As to the habitat diameter, the FH could be equipped with a wider fairing should that be needed, or an inflatable habitat could be used.

Close attention to sustainable overall cost is essential if we are going to maintain a foothold on Mars, rather than just leaving a few footsteps, which on Mars, with its blowing dust, will not last long.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sdsds on 12/30/2015 08:28 pm
I have difficulty understanding the need for a habitat to be launched directly into a lunar or Mars trajectory. Earth orbit rendezvous (as originally proposed by von Braun) for refueling or mating a departure stage could be used at lower cost. Wasn't that even the original plan for Constellation? As to the habitat diameter, the FH could be equipped with a wider fairing should that be needed, or an inflatable habitat could be used.

Close attention to sustainable overall cost is essential if we are going to maintain a foothold on Mars, rather than just leaving a few footsteps, which on Mars, with its blowing dust, will not last long.

What's essential are close attention to cost, and not building in a reliance on unfunded parts of the architecture. The "1.5 launch" CxP architecture would have used Earth Orbit Rendezvous, yes. But the rendezvous would have been with an "Earth Departure Stage" with a long-duration loitering capability. Development of that component is not funded.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 12/30/2015 09:16 pm
Not to mention the fact of relying on an inexistent fairing which:
A) It's not clear that FH can handle a fairing 2.3 times its core and;
B) Even if possible would add significant mass (stock is 4tonnes) and;
C) Is not clear that the HIF, TEL, LC-39A ramp nor any other GSE can handle and it would definitely not be road portable.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 12/30/2015 09:24 pm
This may seem obvious to some, but I don't think it actually can launch 53 tons to LEO.. it's just a reference orbit. That said, the best number I've seen for the fairing mass is 1,750 kg, so if you really want to squeeze a maximum payload to LEO number out of the Falcon Heavy you could probably imagine a payload that doesn't need to go inside the fairing (like some mega-Dragon). Also, this is all old numbers with cross-feed. Maybe this year SpaceX will release a press kit and we'll actually find out what the real vehicle on the pad can do.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Nathan2go on 12/30/2015 10:47 pm
I agree the F9H could have a huge impact on manned Mars exploration.  In the same way that the COTS program was very successful at allowing NASA to help fund companies that wanted to get into the LEO cargo business (i.e. SpaceX and Orbital Sciences), commercial companies can now demand a piece of the manned Mars program, with a con-ops optimized for numerous flights with reusable rockets.

1) One of the core principles of the Mar Direct concept was that Mars-Surface-Rendezvous was better than building large mono-ships in LEO.  This principle was only used to justify having the crew fly out separately from their Mars Ascent Vehicle (MAV/ERV); but we could take the idea further and deliver most of the mission mass to Mars in 1-5 ton landers, which could then be retrieved by truck (everything except the nearly empty Hab and empty MAV).  These could be sent out 2 years ahead of the crew, by vehicles in the F9H class.

2) The 2013 Mars DRM-5 from NASA  included nuclear thermal engines, which were rejected from Mars Direct in order to speed the schedule etc.  On orbit-transfer of LOX (from a commercial space company) provides the same ability to boost the capabilities of the SLS, without the difficulty of large nuclear developments.  For a 130 ton Earth Departure Stage to throw a 130 ton payload to Mars on a 6 month trajectory, it would need to top-off with an extra 210 tons of propellant.   Commercial companies offering F9H class rockets could credibly provide this amount of LOX to LEO to support anticipated SLS launch rates.

With those two markets, companies like SpaceX and Blue Origin could get funding (from NASA and investors) to develop a new generation of larger (colonization-class) rockets.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jcc on 12/30/2015 11:52 pm
This may seem obvious to some, but I don't think it actually can launch 53 tons to LEO.. it's just a reference orbit. That said, the best number I've seen for the fairing mass is 1,750 kg, so if you really want to squeeze a maximum payload to LEO number out of the Falcon Heavy you could probably imagine a payload that doesn't need to go inside the fairing (like some mega-Dragon). Also, this is all old numbers with cross-feed. Maybe this year SpaceX will release a press kit and we'll actually find out what the real vehicle on the pad can do.

Better still, launch it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 12/31/2015 02:17 am
I just looked at the SpaceX FH description page and it describes an FH that is based on the F9FT: 170klbf M1DFT engines, larger US and higher GLOW than the FHv1.1 based version. The problem is the some of the text, performance values and prices don't seem to be updated to reflect the FHFT physical description.

One of the items with the text is cross feed is still mentioned. That questions is there still a long term cross feed in the works or not? The many statements recently is that there will not be a cross feed. But that may not be correct. B ut that for now and until sometime in the future when a cross-feed is deemed useful it will be an option.

One of the items is that the 53mt is seemingly possible by a FHFT expendable, but if there was a FHFTcrossfeed it would be possible to have a 53mt reusable vehicle.

BTW if there was eventually a FHFT crossfeed what would its max LEO payload be? 70mt?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dave G on 12/31/2015 02:25 am
How close to the cross-fed enabled 53mt payload to LEO is the non-cross-fed fully expended full thrust falcon heavy? I'm guessing it's fairly close...

This may have changed, but last I heard there were 3 flavors of Falcon Heavy:
1) Fully expendable, cross-fed: 21mt GTO, 53mt LEO
2) Reusable boosters RTLS, expendable center core, cross-fed: 14mt GTO
3) All 3 first stages RTLS, not cross-fed: 7mt GTO

Of these, I believe 3) will be most important, as it covers virtually all current comsats with a fully reusable set of first stages that RTLS.  If refurbishing the stages is relatively easy, as SpaceX suggests, then this configuration should end up being less expensive than an expendable Falcon 9.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 12/31/2015 02:37 am
1) Ghost of Elon past
2) Ghost of Elon present
3) Ghost of Elon future

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 12/31/2015 02:49 am
How close to the cross-fed enabled 53mt payload to LEO is the non-cross-fed fully expended full thrust falcon heavy? I'm guessing it's fairly close...

This may have changed, but last I heard there were 3 flavors of Falcon Heavy:
1) Fully expendable, cross-fed: 21mt GTO, 53mt LEO
2) Reusable boosters RTLS, expendable center core, cross-fed: 14mt GTO
3) All 3 first stages RTLS, not cross-fed: 7mt GTO

Of these, I believe 3) will be most important, as it covers virtually all current comsats with a fully reusable set of first stages that RTLS.  If refurbishing the stages is relatively easy, as SpaceX suggests, then this configuration should end up being less expensive than an expendable Falcon 9.
The item not discussed is that your options is based on FHv1.1 performance and not the additional 33% that is a possible increase provided by a FHFT. If you straight X 33% the performance values you get
1) Fully expendable, cross-fed: 27mt GTO, 70mt LEO
2) Reusable boosters RTLS, expendable center core, cross-fed: 18.5mt GTO
3) All 3 first stages RTLS, not cross-fed: 8.7mt GTO

Unfortunately performance values don't usually scale like that so these new values are only a guide not anything more. In some case there could be more and others less due to the interactions of what the changes are and how they affect the flight performance to an orbit.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 12/31/2015 06:52 am

How close to the cross-fed enabled 53mt payload to LEO is the non-cross-fed fully expended full thrust falcon heavy? I'm guessing it's fairly close...

This may have changed, but last I heard there were 3 flavors of Falcon Heavy:
1) Fully expendable, cross-fed: 21mt GTO, 53mt LEO
2) Reusable boosters RTLS, expendable center core, cross-fed: 14mt GTO
3) All 3 first stages RTLS, not cross-fed: 7mt GTO

Of these, I believe 3) will be most important, as it covers virtually all current comsats with a fully reusable set of first stages that RTLS.  If refurbishing the stages is relatively easy, as SpaceX suggests, then this configuration should end up being less expensive than an expendable Falcon 9.

Nope. That was the plan, cross feed is not in the current iteration of FH. It could still be added in the future, but I doubt it.

So the only question for an FH launch is where the core booster will end up. RTLS, on a barge, or expended.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 12/31/2015 07:21 am

The item not discussed is that your options is based on FHv1.1 performance and not the additional 33% that is a possible increase provided by a FHFT.

Any credible source for this claim?

Even though they released the 53t number many years ago, they already knew then what their M1D will finally be capable of.

And even if the original numbers were for the reduced-thrust version of M1D, your 33% scaling factor is way too high for the payload increase for that 15% engine thrustupgrade.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 12/31/2015 07:52 am
And even if the original numbers were for the reduced-thrust version of M1D, your 33% scaling factor is way too high for the payload increase for that 15% engine thrustupgrade.

Much of the performance increase is in the upper stage enlargement and the larger M-vac nozzle.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 12/31/2015 08:38 am
And even if the original numbers were for the reduced-thrust version of M1D, your 33% scaling factor is way too high for the payload increase for that 15% engine thrustupgrade.

Much of the performance increase is in the upper stage enlargement and the larger M-vac nozzle.

Larger M-vac nozzle? where is this information from?

And upper stage enlargement helps payload to higher orbits more than payload to LEO. 30% increase in GTO payload may mean 24% increase in LEO payload.

And, if spaceX knew they were going to expand the second stage again before FH, I think the effect of this is already calculated in the original FH capasity numbers.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 12/31/2015 08:48 am
Larger M-vac nozzle? where is this information from?

They made the interstage longer and upgraded the pushers for stage separation to accomodate a larger nozzle extension.

And upper stage enlargement helps payload to higher orbits more than payload to LEO. 30% increase in GTO payload may mean 24% increase in LEO payload.

And, if spaceX knew they were going to expand the second stage again before FH, I think the effect of this is already calculated in the original FH capasity numbers.

Yes.

Maybe.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Darkseraph on 12/31/2015 09:08 am
Has SpaceX said anything about engine out capability with reuse? 



Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dave G on 12/31/2015 09:55 am
Has SpaceX said anything about engine out capability with reuse?

Excellent question!

I haven't heard anything specifically from SpaceX on this, but I always assumed the extra propellant required for engine out capability was dual use. This is similar in concept to Dragon v2, where the SuperDraco propellant is used for either LAS or RTLS, but not both.

Last I heard, the first stage uses 3 Merlin engines for supersonic retrograde propulsion, and 1 Merlin engine (the center one) for landing.  So if the center engine fails during ascent, there's no way they could return the stage. 

But again, if an engine fails during ascent, they'll need to burn the first stage longer to make the intended orbit with less total thrust, which ends up requiring more propellant.  And SpaceX says they can tolerate 2 engine failures during ascent, which would require even more extra propellant to make the intended orbit with the remaining 7 engines.

My bet: If an engine fails, they won't have enough propellant left to land the first stage anywhere, either RTLS or a barge.  So the extra fuel for engine out is that same fuel for reuse.
 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: StuffOfInterest on 12/31/2015 10:17 am
Although an engine out may not leave enough fuel for RTLS I don't think it is a certainty.  If the engine out occurs late during first stage flight then it may leave enough fuel to still make it back.  Beyond that, I don't think there is fine grained enough monitoring of the fuel level to decide if there is enough to make it so the computer will likely just try to land and if fuel runs out during one of the three burns then the rocket drops either just off shore or on the landing pad.  Even with a hard landing I bet SpaceX would love to get back a failed engine to figure out what went wrong with it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dave G on 12/31/2015 10:33 am
The item not discussed is that your options is based on FHv1.1 performance and not the additional 33% that is a possible increase provided by a FHFT.

Even though they released the 53t number many years ago, they already knew then what their M1D will finally be capable of.

Originally, way back with Falcon 5, they were already talking about a heavy version.  Then when they went to Falcon 9, then called it "Falcon 9 Heavy". 

Then when they did a press event for "Falcon Heavy" (leaving the "9" out of the name), that was where they first mentioned 53mt to LEO.  I'm pretty sure this number was based on the Falcon 9 v1.1 improvements that they were just about to test at VAFB.  At that time, the 53mt included a cross-fed center core, and that configuration was fully expendable.  I believe the other numbers Elon mentioned back then (http://aviationweek.com/blog/falcon-9-performance-mid-size-geo) (7mt GTO with 3 cores RTLS, 14mt GTO with 2 cores RTLS) are all based on the Falcon 9 v1.1 improvements.

But since then, they've made even more performance improvements with Falcon 9.  My guess: Elon probably wanted to call this Falcon 9 v1.2, but that would tend to scare some customers, so he mentions these performance improvements only in passing without any specific numbers.

I've also heard the first versions of Falcon Heavy will not be cross-fed, but they haven't ruled out using this in the future.

So the bottom line is that we don't really know what the FH numbers will be exactly.  I suspect SpaceX will revise the numbers when they get closer to launch.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dave G on 12/31/2015 11:18 am
Although an engine out may not leave enough fuel for RTLS I don't think it is a certainty.  If the engine out occurs late during first stage flight then it may leave enough fuel to still make it back.  Beyond that, I don't think there is fine grained enough monitoring of the fuel level to decide if there is enough to make it so the computer will likely just try to land and if fuel runs out during one of the three burns then the rocket drops either just off shore or on the landing pad.  Even with a hard landing I bet SpaceX would love to get back a failed engine to figure out what went wrong with it.

I'm sure SpaceX would love to get back a failed engine to figure out what went wrong, but without enough fuel to control descent, a RTLS attempt could land the stage significantly off course.  If it blew up some building, RTLS would be set back for years...

They could attempt to land it on a barge, but now that RTLS is working, I doubt SpaceX will want the added expense of deploying a landing barge for every flight.

Remember, reusability is all about cost savings.  It's not mission critical, so it doesn't need to be highly reliable to work.  It's a just numbers game.  If an engine fails 1 out of every 100 flights, I suspect the safest, least cost option is to ditch it in the ocean, like a regular expendable launcher.  If an engine fails 1 out of every 10 flights, then they have a problem with their engine, so that would need to be fixed.

In other words, an engine failure should be a rare event.  In such rare events, since reuse isn't mission critical, I suspect the best option will be to expend the stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 12/31/2015 02:30 pm
Just by the math if the engine throttle position of the 9 engines is 88% or less the loss of a single engine (shutdown) will not result in any additional prop use. In fact it may result in more residual prop since the remaining 8 engines would throttle back up to 100% and operate at a slightly higher ISP.

It is only when the throttle position is greater than 88% that the additional prop for RTLS would be consumed partially because of increased gravity losses (less acceleration due to the engine loss).

The difficulty is which engine fails and what contingencies the software has for doing RTLS to work around using a failed engine (a different set of 3)?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Im_Utrecht on 12/31/2015 02:34 pm
FH will be manrated like F9
FH's first version will be based on F9v1.1FT but will upgraded in the future.
Probably they will use more composites to save weight, introduce crossfeed and first stage engines that do not dump the exhaust from the turbopumps. (like the merlin 1D vac from s2)

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 12/31/2015 03:11 pm
FH will be manrated like F9
FH's first version will be based on F9v1.1FT but will upgraded in the future.
Probably they will use more composites to save weight, introduce crossfeed and first stage engines that do not dump the exhaust from the turbopumps. (like the merlin 1D vac from s2)
There are a lot of don't knows!
1) performance expendable?
2) performance RTLS?
3) performance with crossfeed?
4) possible upgrades?
5) the higher delta V orbit performce due to having a "larger" US?

The last one is something we have been discussing about a short fall of the FHv1.1 having a too small US. Was the size increase of the F9 US optimized for FH performance or for F9 performance?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 12/31/2015 04:19 pm
[...]
Specifically disruptive to Human BEO exploration plans.  Scimemi, the ISS director for NASA, says he wants to build the HAB Congress just directed NASA to study and have a prototype ready for 2018. Why would we do that, when for a fraction of the cost, we could send up a prototype BA330 on a FH? (that's a rhetorical question)
[...]
A Hab would really have to be tested in EML1/2 space. LEO is very different from deep space. For example, you have 45min of hotness and 45min of coldness. In deep space you have a hot side and a cold side, permanently. So the thermal environment is completely different. You have to worry about MMOD and free oxygen in LEO which are not an issue in deep space. You have a lot less radiation, which you actually want to prove the hab design. You need completely different comm system. And a long list of requirements.
Why I'm saying this? Because for such an Hab, unless you are also including a SEP tug (which has no budget), you are going to worry about the C3=-1km˛/s˛ performance. How much could the Falcon Heavy do? If it can, in fact, do 13 to TMI, then it should be able to do between 17 and 20 tonnes to TLI. The problem is, SLS can do something like 45tonnes with EUS and well more than 25 tonnes with the ICPS. So the prototype would have to have less than half the mass of the final hab if it were to fit into a FH.
And I didn't get into the fact that SLS will have an 8.4m fairing (7.5m internal) vs the 5.2m (4.7 internal) of the FH. I rather see FH as an opportunity to send something commercial to LEO very cheaply or a Cygnus derived module to TLI, rather than the full Hab.

You also didn't get into the fact that the FH will be ready in six months and the SLS with 8.4m fairing and EUS will be lucky to be ready in six years(and $20B).  And conveniently didn't get into the fact that only one system will be affordable to operate. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 12/31/2015 05:25 pm
You also didn't get into the fact that the FH will be ready in six months and the SLS with 8.4m fairing and EUS will be lucky to be ready in six years(and $20B).  And conveniently didn't get into the fact that only one system will be affordable to operate.
Actually, you started talking about using FH for the Hab prototype. The Hab will fly with SLS/EUS, this is the current plan and thus it will be sized accordingly.
And regarding affordability, it's not what you believe to be but what US Congress is actually willing to pay. And in the 2016 budget, US Congress actually decided that NASA is not spending enough on SLS. Also, they added quite a few millions to start up the EUS effort. So the definitive Hab will fly on SLS/EUS and will be more than six years. The issue is the prototype and how representative it will be.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mongo62 on 12/31/2015 05:59 pm
You also didn't get into the fact that the FH will be ready in six months and the SLS with 8.4m fairing and EUS will be lucky to be ready in six years(and $20B).  And conveniently didn't get into the fact that only one system will be affordable to operate.
Actually, you started talking about using FH for the Hab prototype. The Hab will fly with SLS/EUS, this is the current plan and thus it will be sized accordingly.
And regarding affordability, it's not what you believe to be but what US Congress is actually willing to pay. And in the 2016 budget, US Congress actually decided that NASA is not spending enough on SLS. Also, they added quite a few millions to start up the EUS effort. So the definitive Hab will fly on SLS/EUS and will be more than six years. The issue is the prototype and how representative it will be.

Perhaps FH could launch "a" hab, but not the Hab you are referring to. A Bigelow BA330 weighs about 20t, which is about what the FH can put into high Earth orbit. I am sure that Bigelow would love to have one of their stations there sooner rather than (much) later.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 12/31/2015 07:37 pm
I stated that it would be perfect for a Cygnus based hab or, may be, a lightened BA330 sent to TLI. Who knows what they meant by a prototype by 2018. That's not even clear if it would be orbital.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Im_Utrecht on 01/01/2016 04:41 am
Happy newyear everybody and i wish you a good 2016.

Who knows how weight an upgraded FH can sent to TLI in 2018 ?   ;)

I have a question;
A spacestation like the BA330 that is designed to withstand the rigors of space for years cannot survive the three first minutes of launch ? I mean considering the shape and size is it not possibele to adapt the design a bit so that the fairing might not be needed thus saving a lot of weight ?

I do not know if the size increase of S2 was optimized for F9 or FH. Perhaps they made a compromise but i have the feeling that it was for F9. Maybe later they could incease it again for FH but i remember that Elon some time ago said that he was afraid of bending.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Patchouli on 01/01/2016 04:51 am
I stated that it would be perfect for a Cygnus based hab or, may be, a lightened BA330 sent to TLI. Who knows what they meant by a prototype by 2018. That's not even clear if it would be orbital.

Better still launch a standard BA330 with a ion propulsion module vs using the FH upper stage to reach high orbits or escape.

Heck even the addition of something like an enlarged PAM upper stage would probably increase the payload enough.
Though Spacex doesn't seem to have any plans to add a third stage esp a anything using solids.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: intrepidpursuit on 01/01/2016 06:09 am
Happy newyear everybody and i wish you a good 2016.

Who knows how weight an upgraded FH can sent to TLI in 2018 ?   ;)

I have a question;
A spacestation like the BA330 that is designed to withstand the rigors of space for years cannot survive the three first minutes of launch ? I mean considering the shape and size is it not possibele to adapt the design a bit so that the fairing might not be needed thus saving a lot of weight ?

I do not know if the size increase of S2 was optimized for F9 or FH. Perhaps they made a compromise but i have the feeling that it was for F9. Maybe later they could incease it again for FH but i remember that Elon some time ago said that he was afraid of bending.

The thing everyone keeps forgetting when talking about a hab that doesn't need a fairing is that anything you build into the hab you have to take to orbit. But the fairing separates early in S2 flight, so it does not count directly against your payload weight the way a built in fairing would. This is why most satellites opt to use a fairing rather than have an aerodynamic design capable of hypersonic flight through the atmosphere. The only reason dragon does it is that it has to fly back anyway. Cygnus doesn't use a fairing for the reasons stated above.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Im_Utrecht on 01/01/2016 07:59 pm

Cygnus does use a fairing on the atlas V, see the year in review.
I agree that a build in fairing is not a good option.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/03/2016 01:02 am
I believe the mass values on the FH SpaceX description page are that of the v1.1 and not of the FT. If they are then the FHv1.1 had a T/W of 1.29. But even with new and higher mass values for FHFT the T/W could be more than 1.4.

If they lower the T/W by throttling back the center core to 75% they get back to the T/W of ~1.29. An almost 25% longer burn time of the center core than the boosters would have an interesting performance boost to the FHFT  almost like that of a crossfeed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante2121 on 01/03/2016 03:05 am
Is it out of the realm of possibility for the center core of the falcon heavy to RTLS by completing an orbit?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Arcas on 01/03/2016 03:08 am
Is it out of the realm of possibility for the center core of the falcon heavy to RTLS by completing an orbit?
Yes
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante2121 on 01/03/2016 03:18 am
Is it out of the realm of possibility for the center core of the falcon heavy to RTLS by completing an orbit?
Yes

I set myself up for that answer.  I'm looking to understand why not.  How much faster would it have to be traveling?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: macpacheco on 01/03/2016 03:48 am
Is it out of the realm of possibility for the center core of the falcon heavy to RTLS by completing an orbit?
Yes

I set myself up for that answer.  I'm looking to understand why not.  How much faster would it have to be traveling?

It would need a lot of extra fuel to achieve sub orbital flight to go around the earth once.

Lets start from Musk's words: for ASDS landing, staging happens around 8000 Km/h at 100Km altitude.
For a once around orbit, speed would need to be something like twice as much.
Its much cheaper to turn the stage around for RTLS than to go once around.
Also RTLS results in a much slower re-entry, meaning a cheaper entry burn.
In a once around orbit, re-entry speed will be much higher, which would also require more fuel for entry.

Everything is much more difficult, as the first stage would be going quite deep into the second stage job (although without the 2nd stage attached).

Then there's the question if the stage could handle the extended coast after the end of the boostup burn and entry burn (something like 2 hours coast period), it would get ultra cold, something critical could freeze and prevent the re-entry burn.

Oh, and there's also the nagging problem of the stage flying over florida to land. Big complications with the FAA.

Even if fuel weren't an issue, there's a whole can of worms being openned in this scenario.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: KelvinZero on 01/03/2016 03:56 am
Is it out of the realm of possibility for the center core of the falcon heavy to RTLS by completing an orbit?
Yes

I set myself up for that answer.  I'm looking to understand why not.  How much faster would it have to be traveling?
I think it would be in orbit pretty much by definition. It is following some ellipse that did not intersect the earth except possibly to skim at this one point.

..although, apparently a F9 first stage can put itself into orbit without payload. You would guess therefore that a falcon heavy could put its central core into orbit PLUS some additional payload if it wanted to, skipping the upper stage. Presumably it doesn't deliver enough to make this attractive, especially if including margin to return it.

I guess you would have to redesign your central core as a lifting body or something rather than include enough fuel to slow it sufficiently for a conventional 1st core landing.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Nathan2go on 01/03/2016 04:03 am
Is it out of the realm of possibility for the center core of the falcon heavy to RTLS by completing an orbit?
Certainly the FH center core could be made to reach orbit.   Those boosters basically are nearly light enough to fly to orbit as a single stage (perhaps with 0 payload), were it not for the sea-level nozzle optimization.  With the center of three cores optimized for high altitude and perhaps fewer engines, a reasonable payload capacity would result.

The problem is re-use.  The first stage cores are a bad shape for high speed re-entry: too long and skinny.  They are only stable when falling tail first, and you can't put pica-x insulating tiles on the engines, since they would shake loose, or the glue would melt.  As it is, F9 first stage doesn't even try to re-enter at Mach 6, it slows down first.  A Mach 25 re-entry would be much hotter.

If you watch the SpaceX re-usability video, it shows the upper stage re-entering nose first, then turning around in mid-flight (presumably as sub-sonic speed); the nose has a blunt heat shield.  Similarly, the Kistler K1 upper stage was supposed to re-enter nose first, using a blunt heat shield.  Also, the MD Delta Clipper was supposed to re-enter nose first, and turn-around in mid-flight (at sub-sonic speed).  The nose-first re-entry and mid-flight turn-around work fine for things that are short and stubby like a beer can and have a blunt heatshield.

An F9 first stage is too skinny to turn-around in mid-flight (even if you could stabilize it); it would snap in half unless it was heavily reinforced.

It is not out of the question to build an expendable center core that reaches orbit, and use parallel staging like the space shuttle, the early SLS block configuration, and Arian V.  This avoids the risks of starting engines in mid-flight.  However without a credible path to re-usability, I would not expect SpaceX to be interested.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mongo62 on 01/03/2016 03:49 pm
There's a very interesting post on r*ddit called "Recalculating the ULA reusability analysis in context of SpaceX" that goes into quite a lot of detail on the various costs of reusable rockets. One of the responses by the original poster was of particular interest:

Quote
Either way, I have a few observations you might find interesting:

Ground costs are extremely important. It is a very significant part of the costs. In my second scenario, more than half of the Reuse Index goes to ground costs. If we want orders of magnitude in savings, this will need to be practically 0. Spaceports will really need to operate like airports to even have a shot.

The next biggest chunk is rebuilding the second stage, or in general : Fru. Trading off Cru to increase Fru is worthwhile as long as Cru * ( 1 - Fru ) decreases (if refurbishment costs remain the same, i.e. Crf goes down proportionally so that Crf * Cru stays the same). The initial cost of the rocket is divided by n, so as more launches happen this goes to zero. If we can make a fully reusable rocket at 10x the cost that can fly hundreds of times, it is totally worth it. This is pretty much the idea behind SSTO spaceplanes.

Refurbishment costs should be low, but aren't the dealbreaker as long as they don't exceed 25% of the total rocket price (so closer to 35% of the first stage price). Spending several million on refurbishing per launch is totally doable. Using Cru = 1.2, Fru = 0.7, Crf = 0.25 and Cground = 0.2 (more realistic value from ULA tweets), you still get a 20% drop in costs after 10 flights. This would be a failure according to SpaceX, but still a significant and worthwhile competitive advantage.

The F factor from ULA barely makes a difference. It increases the costs by 0.03-0.04 index points even at 20 launches. This is because the reduced production volume only counts for the first stage, not the entire rocket! At 20 launches you may pay almost 60% more to build the first stage, but that obviously only means a 3% increase per launch. I've actually found a mistake in my formula here: I apply this factor to the entire cost of the reusable rocket, while I should only apply it to the fraction that is reused. The first term should be (F * Fru * Cru + ( 1 - Fru ) * Cru ). This would reduce the impact even more. This term can pretty much be ignored unless the rate exponent goes down significantly.

These observations may be more useful than what I originally wrote. It shows a part of the business model behind the Falcon Heavy: If they can achieve second stage reusability with it and cut production costs enough to make it worthwhile (second bullet point above), they have the winning formula. We can also see why Elon isn't exactly worried about refurbishing costs: Even at 25% there is a strong business case to be made. Building the Merlins from scratch to be reusable without significant maintenance is the killer breakthrough here. Everything hinges on that. I'm very interested to see the static fire because that will pretty much be the deciding factor according to my analysis. If they end up needing STS levels of disassembly, refurbishment, testing and reassembly... That's pretty much lights out for reusability then. Maybe the Raptor engines can save the day but it would still suck.

So maybe the primary motive behind the FH was not that it could put massive payloads into LEO in expendable mode (since as many people have pointed out, these payloads are few and far between), but that it could put a future reusable second stage with its increased weight, plus an F9-sized payload,  into LEO and still RTLS. If the first stage core and booster plus the second stage and payload fairing are all reusable at a reasonable maintenance cost, then the cost per kg to orbit can drop like a stone. F9 alone would not have the capacity to do this, you need the FH.

Of course SpaceX's plans may have changed since the decision to develop FH.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 01/03/2016 05:00 pm
There's a very interesting post on r*ddit called "Recalculating the ULA reusability analysis in context of SpaceX" that goes into quite a lot of detail on the various costs of reusable rockets. One of the responses by the original poster was of particular interest:

Quote
Either way, I have a few observations you might find interesting:

Ground costs are extremely important. It is a very significant part of the costs. In my second scenario, more than half of the Reuse Index goes to ground costs. If we want orders of magnitude in savings, this will need to be practically 0. Spaceports will really need to operate like airports to even have a shot.

The next biggest chunk is rebuilding the second stage, or in general : Fru. Trading off Cru to increase Fru is worthwhile as long as Cru * ( 1 - Fru ) decreases (if refurbishment costs remain the same, i.e. Crf goes down proportionally so that Crf * Cru stays the same). The initial cost of the rocket is divided by n, so as more launches happen this goes to zero. If we can make a fully reusable rocket at 10x the cost that can fly hundreds of times, it is totally worth it. This is pretty much the idea behind SSTO spaceplanes.

Refurbishment costs should be low, but aren't the dealbreaker as long as they don't exceed 25% of the total rocket price (so closer to 35% of the first stage price). Spending several million on refurbishing per launch is totally doable. Using Cru = 1.2, Fru = 0.7, Crf = 0.25 and Cground = 0.2 (more realistic value from ULA tweets), you still get a 20% drop in costs after 10 flights. This would be a failure according to SpaceX, but still a significant and worthwhile competitive advantage.

The F factor from ULA barely makes a difference. It increases the costs by 0.03-0.04 index points even at 20 launches. This is because the reduced production volume only counts for the first stage, not the entire rocket! At 20 launches you may pay almost 60% more to build the first stage, but that obviously only means a 3% increase per launch. I've actually found a mistake in my formula here: I apply this factor to the entire cost of the reusable rocket, while I should only apply it to the fraction that is reused. The first term should be (F * Fru * Cru + ( 1 - Fru ) * Cru ). This would reduce the impact even more. This term can pretty much be ignored unless the rate exponent goes down significantly.

These observations may be more useful than what I originally wrote. It shows a part of the business model behind the Falcon Heavy: If they can achieve second stage reusability with it and cut production costs enough to make it worthwhile (second bullet point above), they have the winning formula. We can also see why Elon isn't exactly worried about refurbishing costs: Even at 25% there is a strong business case to be made. Building the Merlins from scratch to be reusable without significant maintenance is the killer breakthrough here. Everything hinges on that. I'm very interested to see the static fire because that will pretty much be the deciding factor according to my analysis. If they end up needing STS levels of disassembly, refurbishment, testing and reassembly... That's pretty much lights out for reusability then. Maybe the Raptor engines can save the day but it would still suck.

So maybe the primary motive behind the FH was not that it could put massive payloads into LEO in expendable mode (since as many people have pointed out, these payloads are few and far between), but that it could put a future reusable second stage with its increased weight, plus an F9-sized payload,  into LEO and still RTLS. If the first stage core and booster plus the second stage and payload fairing are all reusable at a reasonable maintenance cost, then the cost per kg to orbit can drop like a stone. F9 alone would not have the capacity to do this, you need the FH.

Of course SpaceX's plans may have changed since the decision to develop FH.
100% agreed.  I personally think we'll be seeing a lot of FHs flights for exactly this reason, and mission specific reusable second stages (LEO satellite deployers, tankers, etc)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/03/2016 06:22 pm
There's a very interesting post on r*ddit called "Recalculating the ULA reusability analysis in context of SpaceX" that goes into quite a lot of detail on the various costs of reusable rockets. One of the responses by the original poster was of particular interest:

Quote
Either way, I have a few observations you might find interesting:

Ground costs are extremely important. It is a very significant part of the costs. In my second scenario, more than half of the Reuse Index goes to ground costs. If we want orders of magnitude in savings, this will need to be practically 0. Spaceports will really need to operate like airports to even have a shot.

The next biggest chunk is rebuilding the second stage, or in general : Fru. Trading off Cru to increase Fru is worthwhile as long as Cru * ( 1 - Fru ) decreases (if refurbishment costs remain the same, i.e. Crf goes down proportionally so that Crf * Cru stays the same). The initial cost of the rocket is divided by n, so as more launches happen this goes to zero. If we can make a fully reusable rocket at 10x the cost that can fly hundreds of times, it is totally worth it. This is pretty much the idea behind SSTO spaceplanes.

Refurbishment costs should be low, but aren't the dealbreaker as long as they don't exceed 25% of the total rocket price (so closer to 35% of the first stage price). Spending several million on refurbishing per launch is totally doable. Using Cru = 1.2, Fru = 0.7, Crf = 0.25 and Cground = 0.2 (more realistic value from ULA tweets), you still get a 20% drop in costs after 10 flights. This would be a failure according to SpaceX, but still a significant and worthwhile competitive advantage.

The F factor from ULA barely makes a difference. It increases the costs by 0.03-0.04 index points even at 20 launches. This is because the reduced production volume only counts for the first stage, not the entire rocket! At 20 launches you may pay almost 60% more to build the first stage, but that obviously only means a 3% increase per launch. I've actually found a mistake in my formula here: I apply this factor to the entire cost of the reusable rocket, while I should only apply it to the fraction that is reused. The first term should be (F * Fru * Cru + ( 1 - Fru ) * Cru ). This would reduce the impact even more. This term can pretty much be ignored unless the rate exponent goes down significantly.

These observations may be more useful than what I originally wrote. It shows a part of the business model behind the Falcon Heavy: If they can achieve second stage reusability with it and cut production costs enough to make it worthwhile (second bullet point above), they have the winning formula. We can also see why Elon isn't exactly worried about refurbishing costs: Even at 25% there is a strong business case to be made. Building the Merlins from scratch to be reusable without significant maintenance is the killer breakthrough here. Everything hinges on that. I'm very interested to see the static fire because that will pretty much be the deciding factor according to my analysis. If they end up needing STS levels of disassembly, refurbishment, testing and reassembly... That's pretty much lights out for reusability then. Maybe the Raptor engines can save the day but it would still suck.

So maybe the primary motive behind the FH was not that it could put massive payloads into LEO in expendable mode (since as many people have pointed out, these payloads are few and far between), but that it could put a future reusable second stage with its increased weight, plus an F9-sized payload,  into LEO and still RTLS. If the first stage core and booster plus the second stage and payload fairing are all reusable at a reasonable maintenance cost, then the cost per kg to orbit can drop like a stone. F9 alone would not have the capacity to do this, you need the FH.

Of course SpaceX's plans may have changed since the decision to develop FH.
100% agreed.  I personally think we'll be seeing a lot of FHs flights for exactly this reason, and mission specific reusable second stages (LEO satellite deployers, tankers, etc)
Yes.
If 1st stage refurbishment costs $3M and a 1st stage cost to manufacture (even at $30M) flies 10X that is only an additional $12M per flight for a FHR than for a F9R at 3+ times the payload capability.
F9R ~ price estimate of $42M - $1,426/lb [13500kg]
FHR ~ price estimate of $56M - $570/lb [45000kg]

A dual manifested sat flight on a FHR would be $28M+ integration charges for each sat vs $42M+ integration charges on an F9R.

A price of $570/lb starts to get to the magical large structure in-space construction viability points such as for an SPS.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 01/07/2016 10:29 am
That would be a second FH launch inside 2016. That's...eh..very optimistic of him... :P
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH on 01/07/2016 11:52 am
That would be a second FH launch inside 2016. That's...eh..very optimistic of him... :P

Optimistic? Really? Why? He clearly has much better visibility of SpaceX future schedule, since he is buying into it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 01/07/2016 11:59 am
Optimistic? Really? Why? He clearly has much better visibility of SpaceX future schedule, since he is buying into it.

Here is my take on it.

Company CEOs tend to not make an announcement like that, unless they either feel fairly confident that they will not bite their tongue soon-ish, or if there is a hidden agenda behind (like investor/internal company goodwill, putting pressure to the contractor or the competition etc etc).

 FH flying 2+ times inside 2016 seems too good to be true. I was thinking that even getting it to fly inside 2016 would be considered an accomplishment (given the need for SX to launch quickly with F9 due to CRS-7 downtime, as well as the need to finish work on LC-39A)

Moreover, they would need to also provide an additional landing spot for one of the demo boosters. I know that they have LZ-1 and one barge ready, not really know what the status on the second east coast barge is though.

At the same time, I always thought that the STP-2 mission would come after the Demo flight. For example, take a look at this.

Quote
LightSail and Prox-1 will launch to a circular, 720-kilometer orbit aboard a SpaceX Falcon Heavy. Liftoff is currently scheduled for Sept. 15, 2016.
http://www.planetary.org/blogs/jason-davis/2015/20151026-lightsail-ppod-fit-check.html (http://www.planetary.org/blogs/jason-davis/2015/20151026-lightsail-ppod-fit-check.html)

So this could presumably make ViaSat-2 the third "planned" mission inside 2016.

I just can't see it happening.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: macpacheco on 01/07/2016 12:23 pm
The demo mission is likely to be an existing FH manifest mission.
Its mostly a question of how much discount SpaceX will need to give to the customer for the extra risk.
Ok, I don't know that for sure, but that's what smart money would say.

Better get some money for that launch instead of zero money.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH on 01/07/2016 01:29 pm
Optimistic? Really? Why? He clearly has much better visibility of SpaceX future schedule, since he is buying into it.

Here is my take on it.

Company CEOs tend to not make an announcement like that, unless they either feel fairly confident that they will not bite their tongue soon-ish, or if there is a hidden agenda behind (like investor/internal company goodwill, putting pressure to the contractor or the competition etc etc).

 FH flying 2+ times inside 2016 seems too good to be true. I was thinking that even getting it to fly inside 2016 would be considered an accomplishment (given the need for SX to launch quickly with F9 due to CRS-7 downtime, as well as the need to finish work on LC-39A)

Moreover, they would need to also provide an additional landing spot for one of the demo boosters. I know that they have LZ-1 and one barge ready, not really know what the status on the second east coast barge is though.

At the same time, I always thought that the STP-2 mission would come after the Demo flight. For example, take a look at this.

Quote
LightSail and Prox-1 will launch to a circular, 720-kilometer orbit aboard a SpaceX Falcon Heavy. Liftoff is currently scheduled for Sept. 15, 2016.
http://www.planetary.org/blogs/jason-davis/2015/20151026-lightsail-ppod-fit-check.html (http://www.planetary.org/blogs/jason-davis/2015/20151026-lightsail-ppod-fit-check.html)

So this could presumably make ViaSat-2 the third "planned" mission inside 2016.

I just can't see it happening.

If the first F9H launch goes well, what's to stop them fairly quickly doing another one? They have the manufacturing capability AIUI. The first two F9 flights were within 6 months of each other, the next 5 are within 3 months. It's not like they are still very slow at launching stuff (fingers crossed)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 01/07/2016 03:09 pm
If the first F9H launch goes well, what's to stop them fairly quickly doing another one? They have the manufacturing capability AIUI. The first two F9 flights were within 6 months of each other, the next 5 are within 3 months. It's not like they are still very slow at launching stuff (fingers crossed)

As long as they don't refly stages, their production rate will limit them. As Elon Musk said, at the moment a core every 3 weeks, thats 17 cores in a year. They may have 4 in stock but they won't launch the last two produced this year. So they have 19 cores to launch. That's 14 F9 plus 2 FHeavy or 11 F9 plus 3 FHeavy. I am willing to add one or two reflown cores for 12 or 13 F9 + 3 FHeavy. That's on the optimistic side of realistic. :)

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 01/07/2016 03:17 pm
My money is on the demo launch being a SpaceX special.  They've been trying to sell the payload on that flight for years without success.  I don't think a customer is suddenly going to change their minds now, especially after CRS-7 reminds them that SpaceX is occasionally fallible.

If anything, I'm a little surprised that the lightsail team hasn't taken advantage of the demo flight.  But I think for them the cost to build their payload is really significant, so they don't want to lose it --they've already lost three or so sails by trying to take advantage of bargain basement flights, they're tired of it.

So, my prediction: small noncommercial payload so they can demo/test RTLS or ASDS of the center core (which client commitments would otherwise force them to defer until they find an appropriate future payload in the right size window between F9 and FH).

If going further, I'd say the payload would be something like a cubesat to Mars, with just a radio, solar panels, and a little camera.  Remember that one of the first spacex demo flights was going to attempt a TMI at the end.  I think Elon is a sucker for Mars symbolism, but he's not going to let his team get too sidetracked by it.  It might not even be a cubesat, he might just launch his mass simulator toward Mars.  That's a cheap way to get 95% of the bragging rights ("first commercial payload to Mars") with 5% of the work. (But he does have a whole satellite building group in Seattle, they might have some little components they'd like to expose to space.)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 01/07/2016 03:25 pm
The key here is "Spring".  If SpaceX can really get the demo flight off in the spring, and it is successful, then this seems quite reasonable to me.  I'd guess this means SpaceX currently believes they are on track for the demo flight going in this timeframe, for whatever that is worth.

If spring, we should be seeing FH on the test stand at McGregor within the next couple of months.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Bynaus on 01/07/2016 03:29 pm
Quote
Remember that one of the first Dragon demos was going to attempt a TMI at the end.

Never heard of that... Any sources or pointers for that? And - was the attempt successful?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 01/07/2016 03:48 pm
I've been trying to refresh my memory. I think it might have actually been Falcon 1 flight 4?  And the flight was successful, but the TMI relight wasn't.  But SpaceX wasn't in the mood to talk about its failures at the time, and the relight wasn't necessary for flight 5 success.  Perhaps others can fill in my memory?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 01/07/2016 05:10 pm
NASA thinks there will be 2 demo flights of Falcon Heavy in 2016 - see this chart from Spaceport News Magazine:

NASA doesn't "think" it.  It is just regurgitating data publicly available info.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 01/07/2016 06:18 pm
Of course SpaceX's plans may have changed since the decision to develop FH.

I always thought the first purpose for the FH was to grab those mega Defense contracts from DOD.  The amount of profit that SpaceX could book from a DOD FH launch would fund a lot of development.

Seems the FH could be evolving into a great re-useable vehicle for large commsats. 

I fully expect that demo flight to target a 3 core RTLS.  If there isn't a paying payload that requires a ASDS or expendable core than why wouldn't SpaceX try to get back those 3 fully reuseable cores.  How much would that help production in Hawthorne? 

Finally, if there isn't a paying client, even at a large discount, then I think that SpaceX will just use a payload simulator.  They won't spend time or money on doing that ties up too many hours or dollars.  Maybe something like a cheese wheel but nothing more.  They have enough to work on and don't need to put resources into something 'cute'
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: bstrong on 01/07/2016 06:37 pm
I've been noodling on Musk's comment about FH in the post-landing teleconference ( source (http://shitelonsays.com/transcript/postlanding-teleconference-with-elon-musk-2015-12-22)):

Quote
The Falcon Heavy essentially consists of the Falcon 9 with two modified boost stages attached as strap on boosters. That would be quite an exciting aerial ballet with the two side boosters dropping off and doing a symmetric pirouette back to the launch site. We'd need to have another landing spot for the two boosters and then a third one for the center core. Although I think most of the Falcon Heavy missions will see the center core land on a ship most likely. It's really going ridiculously fast. The transfer energy of Falcon Heavy will more than double that of Falcon 9. The maximum transfer energy is approaching a terajoule.

Since, as I understand it, FH should be able to RTLS with pretty much all comsats, I can interpret this in three ways:

1. He expects comsat launches to account for less than 50% of FH launches, and the rest will be either really big or going to Mars.

2. He expects F9 barging to be cheaper than FH RTLS, so very few comsats will need FH (contrary to current manifest).

3. He's planning to deliver comsats to higher energy orbits, maybe even offering direct GEO insertion at a price that makes sense for customers besides the US government.

I find the third possibility most interesting, since it gives them an even stronger advantage than price alone vs. the competition. Plus, it's a nice market segmentation tool, which can help them remain profitable while lowering baseline prices to grow the market.

Does anyone have an estimate for direct GEO insertion payload capability with center core barging?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mongo62 on 01/07/2016 07:07 pm
Does anyone have an estimate for direct GEO insertion payload capability with center core barging?

According to this page (http://space.skyrocket.de/doc_lau_det/falcon-9-heavy.htm):

FH (non-crossfeed, expendable) LEO 45 tonnes, GTO 18.95 tonnes, GEO 9.375 tonnes
FH (non-crossfeed, reusable) LEO 32.45 tonnes, GTO 13.65 tonnes, GEO 6.75 tonnes
FH (crossfeed, expendable) 53 tonnes, GTO 22.34 tonnes, GEO 11.04 tonnes
FH (crossfeed, reusable) 38.25 tonnes, GTO 16.1 tonnes, 7.95 tonnes

These appear to assume v1.1 cores, not FT. Even with the old figures, though, that's enough for a reusable FH to be able to put a substantial comsat directly into GEO. Goodby, competition!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/07/2016 07:24 pm
That is just a crude estimate, the author of that page doesn't have access to any more info than we do. I take SpaceX's figure at face value, though it is certainly is to a low altitude and inclination orbit, perhaps assumes launch from Texas, and probably doesn't include margin for reuse and engine-out. And it certainly includes full thrust enhancements.

On that last point, by the way: margin for engine-out and margin for reuse is shared, which means that the effective penalty for reuse is actually much less for payloads that need a lot of engine-out margin.

(And I don't think the 53 ton figure includes cross feed... Cross feed isn't needed if you have a thrust and propellant density improvement.)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: NovaSilisko on 01/07/2016 07:34 pm
Does anyone have an estimate for direct GEO insertion payload capability with center core barging?

According to this page (http://space.skyrocket.de/doc_lau_det/falcon-9-heavy.htm):

FH (non-crossfeed, expendable) LEO 45 tonnes, GTO 18.95 tonnes, GEO 9.375 tonnes
FH (non-crossfeed, reusable) LEO 32.45 tonnes, GTO 13.65 tonnes, GEO 6.75 tonnes
FH (crossfeed, expendable) 53 tonnes, GTO 22.34 tonnes, GEO 11.04 tonnes
FH (crossfeed, reusable) 38.25 tonnes, GTO 16.1 tonnes, 7.95 tonnes

These appear to assume v1.1 cores, not FT. Even with the old figures, though, that's enough for a reusable FH to be able to put a substantial comsat directly into GEO. Goodby, competition!

That page needs a bit of TLC. It still mentions parachutes for recovery.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 01/07/2016 07:37 pm
Some more estimated numbers, from here (Estimates from Feb 2015).
http://www.spacelaunchreport.com/falconH.html (http://www.spacelaunchreport.com/falconH.html)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/07/2016 07:42 pm
Those are also just Ed Kyle's opinion.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 01/07/2016 07:45 pm
Of course. There are no official numbers, except from what SpaceX list on their site.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: bstrong on 01/07/2016 08:55 pm
Some more estimated numbers, from here (Estimates from Feb 2015).
http://www.spacelaunchreport.com/falconH.html (http://www.spacelaunchreport.com/falconH.html)

Thanks for that link. I don't have the knowledge to extrapolate direct GEO insertion from that, other than to use the escape velocity figure of 3-4t as a lower bound, but even that is useful at the right price.

Wrong thread for this, but looking at the escape velocity payload values for F9FT from the same site, it seems like it might be able to put a 702SP (<2000kg) directly into GEO with S1 recovery, if the mass penalty of the long-duration kit for the S2 isn't too high. This would completely eliminate the main drawback of SEP...

It seems like demonstrating direct GEO insertion (which Shotwell has stated they can do) could really take their launch market disruption to a new level. Or am I wrong to assume that this is a capability commercial customers would take advantage of for an extra, say, $5-10m?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 01/07/2016 09:00 pm
Or am I wrong to assume that this is a capability commercial customers would take advantage of for an extra, say, $5-10m?
Why would SpaceX charge more?  As long as the S1 is recoverable, of course.  Just makes their overall package even more attractive for prospective clients.  They haven't shown a propensity to nickle-and-dime their customers to date, so I don't really see that happening.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 01/07/2016 09:04 pm
It seems like demonstrating direct GEO insertion (which Shotwell has stated they can do) could really take their launch market disruption to a new level. Or am I wrong to assume that this is a capability commercial customers would take advantage of for an extra, say, $5-10m?

I don't know if they would like that offer. I don't think though it would be advisable to do. Direct GEO means the upper stage is one more piece of debris up there that cannot deorbit. Upper stages for GTO deorbit.

Direct GEO is something only the DOD wants and even they seem to move away from it. At least they do it for the new generation of GPS sats. The old ones were delivered to their final orbit. The new ones to which SpaceX is bidding are placed in a transfer orbit that allows for upper stage deorbiting.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: bstrong on 01/07/2016 09:46 pm
I don't know if they would like that offer. I don't think though it would be advisable to do. Direct GEO means the upper stage is one more piece of debris up there that cannot deorbit. Upper stages for GTO deorbit.

Yes, didn't really think that part through. Though SpaceX should be mass-producing small, cheap SEP's soon. Maybe you could add an SEP deorbit kit to the S2, as well. But now the whole thing is starting to sound more like a science project than a near-term capability.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/07/2016 11:28 pm
Just to give you a piece of information about performance. On the NASA NLS II website using the performance query and entering 28.5 degree inclination and 285km circular orbit the output for the F9v1.1 payload value is 16,320kg.

GTO-1800 5,755kg

So if SpaceX sandbagged the listed performance on F9v1.1 shown on their website then how much sandbagging did they do for the FHv1.1 performance they show on their website?

This also means that the max for an F9FT would be:
~LEO(285 circular) 21,705kg
~GTO(-1800) 7,654kg

If this is correct then the FHFT max values for expendable are:
without crossfeed, expendable --- 59,850kg
with crossfeed, expendable --- 70,490kg

Can someone say oops for the SLS program!

Edit: the performance query website is http://elvperf.ksc.nasa.gov/Pages/Query.aspx (http://elvperf.ksc.nasa.gov/Pages/Query.aspx)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: PahTo on 01/07/2016 11:35 pm
Just to give you a piece of information about performance. On the NASA NLS II website using the performance query and entering 28.5 degree inclination and 285km circular orbit the output for the F9v1.1 payload value is 16,320kg.

GTO-1800 5,755kg

So if SpaceX sandbagged the listed performance on F9v1.1 shown on their website then how much sandbagging did they do for the FHv1.1 performance they show on their website?

This also means that the max for an F9FT would be:
~LEO(285 circular) 21,705kg
~GTO(-1800) 7,654kg

If this is correct then the FHFT max values for expendable are:
without crossfeed, expendable --- 59,850kg
with crossfeed, expendable --- 70,490kg

Can someone say oops for the SLS program!

While your point is well taken, SpX has noted that crossfeed is off the table for the foreseeable future (and perhaps forever).  If that has changed, please point to where (its hard to keep up with all of the threads and comments!).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/07/2016 11:48 pm
Cross-feed is also not that advantageous if your engines are already high-thrust and highly throttleable.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/07/2016 11:48 pm
Just to give you a piece of information about performance. On the NASA NLS II website using the performance query and entering 28.5 degree inclination and 285km circular orbit the output for the F9v1.1 payload value is 16,320kg.

GTO-1800 5,755kg

So if SpaceX sandbagged the listed performance on F9v1.1 shown on their website then how much sandbagging did they do for the FHv1.1 performance they show on their website?

This also means that the max for an F9FT would be:
~LEO(285 circular) 21,705kg
~GTO(-1800) 7,654kg

If this is correct then the FHFT max values for expendable are:
without crossfeed, expendable --- 59,850kg
with crossfeed, expendable --- 70,490kg

Can someone say oops for the SLS program!

While your point is well taken, SpX has noted that crossfeed is off the table for the foreseeable future (and perhaps forever).  If that has changed, please point to where (its hard to keep up with all of the threads and comments!).
On that you may be correct. But when was the foreseeable future greater than the next 3 years for SpaceX.

At a minimum if needed they have the 53mt without needing crossfeed. Its when they may want more then we may see a return of crossfeed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/07/2016 11:53 pm
SpaceX may retire Falcon Heavy before doing cross-feed. A large single-core vehicle like BFR may be more operationally efficient and could be fully reusable while getting a lot more payload.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/08/2016 12:01 am
SpaceX may retire Falcon Heavy before doing cross-feed. A large single-core vehicle like BFR may be more operationally efficient and could be fully reusable while getting a lot more payload.
BFR/BFS/MCT still looks to be 10 years out. That is 3 upgrade cycles for SpaceX. If they determine that they need it for their own plans then it will be done. But other than possibly SLS being canceled with Orion being manifested on FH I don't see crossfeed happening either.

Their own plans being missions to Mars of some sort where a crossfeed FH could be required to get the payload they want through TMI. BTW max TMI for FHFT(with crossfeed) should be about 17.4mt and about 13mt without. So they could send a Dragon to Mars with an FHFT(without crossfeed).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/08/2016 12:08 am
SpaceX may retire Falcon Heavy before doing cross-feed. A large single-core vehicle like BFR may be more operationally efficient and could be fully reusable while getting a lot more payload.
BFR/BFS/MCT still looks to be 10 years out....
...[citation needed]
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: su27k on 01/08/2016 12:50 am
Just to give you a piece of information about performance. On the NASA NLS II website using the performance query and entering 28.5 degree inclination and 285km circular orbit the output for the F9v1.1 payload value is 16,320kg.

GTO-1800 5,755kg

So if SpaceX sandbagged the listed performance on F9v1.1 shown on their website then how much sandbagging did they do for the FHv1.1 performance they show on their website?

I think what is listed is just projected FT upgrade's performance, we know real v1.1's GTO performance from past launches, and it's no where near 5755kg...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 01/08/2016 12:51 am
SpaceX may retire Falcon Heavy before doing cross-feed. A large single-core vehicle like BFR may be more operationally efficient and could be fully reusable while getting a lot more payload.
BFR/BFS/MCT still looks to be 10 years out....
...[citation needed]

More than a citation, a few billion dollars is needed.  I think a Raptor powered fully reuseable 2 stage vehicle more capable than the FH is a much more likely next vehicle than the BFR.  Which I agree with oldatlas_guy, is at least 10 years away.  Just based on funds and ongoing development efforts.

I think crossfeed is a sexy idea but there are no payloads for it so why spend any time or money on it.  I'd love to see it someday though.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/08/2016 01:19 am
Just to give you a piece of information about performance. On the NASA NLS II website using the performance query and entering 28.5 degree inclination and 285km circular orbit the output for the F9v1.1 payload value is 16,320kg.

GTO-1800 5,755kg

So if SpaceX sandbagged the listed performance on F9v1.1 shown on their website then how much sandbagging did they do for the FHv1.1 performance they show on their website?

I think what is listed is just projected FT upgrade's performance, we know real v1.1's GTO performance from past launches, and it's no where near 5755kg...
The value comes from the algorithm supplied by SpaceX to NASA for performance based on orbit parameters as part of the NLS II contract. It is for the F9v1.1 and not the FT.

Basically the SES-9 sat which is 5300kg was contracted with SpaceX to fly on a F9v1.1 not an F9FT.  SES believed that at the time the contract was made that SpaceX could do it with just the v1.1.

So the value generated by the NASA website is probably very close to the max actual capability of the v1.1. within just a couple of kg. But this is without any margins for engine out or for anything else. S1 to depletion and S2 to depletion.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RonM on 01/08/2016 01:32 am
SpaceX may retire Falcon Heavy before doing cross-feed. A large single-core vehicle like BFR may be more operationally efficient and could be fully reusable while getting a lot more payload.
BFR/BFS/MCT still looks to be 10 years out....
...[citation needed]

Typical aerospace project time. Of course, SpaceX isn't typical.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 01/08/2016 01:37 am
Quote
So the value generated by the NASA website is probably very close to the max actual capability of the v1.1. within just a couple of kg. But this is without any margins for engine out or for anything else. S1 to depletion and S2 to depletion.

The biggest demonstrated capability that we have about Falcon 9 v1.1 is 4,707kg to GTO-1800.
SES9 was supposed to be a sub-synchronous mission before F9 FT came along. It may still be (if the first stage lands).



Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/08/2016 01:39 am
SpaceX may retire Falcon Heavy before doing cross-feed. A large single-core vehicle like BFR may be more operationally efficient and could be fully reusable while getting a lot more payload.
BFR/BFS/MCT still looks to be 10 years out....
...[citation needed]

Typical aerospace project time. Of course, SpaceX isn't typical.
I hope you are right. I would love to see them produce the Raptor in 3 years and the BFR/MCT 3 years after that in 2022.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: copper8 on 01/08/2016 01:42 am
Don't forget, the first successful flight of the Falcon 1 was less than 10 years ago.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: su27k on 01/08/2016 02:29 am
Just to give you a piece of information about performance. On the NASA NLS II website using the performance query and entering 28.5 degree inclination and 285km circular orbit the output for the F9v1.1 payload value is 16,320kg.

GTO-1800 5,755kg

So if SpaceX sandbagged the listed performance on F9v1.1 shown on their website then how much sandbagging did they do for the FHv1.1 performance they show on their website?

I think what is listed is just projected FT upgrade's performance, we know real v1.1's GTO performance from past launches, and it's no where near 5755kg...
The value comes from the algorithm supplied by SpaceX to NASA for performance based on orbit parameters as part of the NLS II contract. It is for the F9v1.1 and not the FT.

I see what you mean, that number hasn't changed since 2012...

But it's not impossible that they would be think about upgrade v1.1 back in 2012, or more likely what they thought of as v1.1 back in 2012 is actually the FT version of today. I think they said they run out of time qualifying M1D for full thrust for v1.1, so what we call v1.1 today is an underperformed version of the ideal v1.1 they planned back in 2012 (it would also explain why they don't want to give a new version number for FT).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sdsds on 01/08/2016 04:26 am
On the subject of crossfeed and its value given Merlins can throttle, note they can also restart. So some of the center core engines could be intentionally shut down entirely shortly after takeoff, and then relit maybe 150 seconds later as the side boosters were running empty.... Absolutely no new technology required for that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: macpacheco on 01/08/2016 05:47 am
SpaceX may retire Falcon Heavy before doing cross-feed. A large single-core vehicle like BFR may be more operationally efficient and could be fully reusable while getting a lot more payload.
The fact is FHE (with side sticks RTLS and center booster expended) has more performance than pretty much any within earth orbit mission ordered worldwide and likely future missions.
And the number of missions that would require the center booster to be expended is tiny.
So this whole debate is ignoring the obvious extremely low likelyhood that SpaceX will actually need to iterate on FH cross feed.
Having an Eagle Lite type rocket will do everything FH can do, with both stages RTLS.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MP99 on 01/08/2016 07:13 am
I've been noodling on Musk's comment about FH in the post-landing teleconference ( source (http://shitelonsays.com/transcript/postlanding-teleconference-with-elon-musk-2015-12-22)):

Quote
The Falcon Heavy essentially consists of the Falcon 9 with two modified boost stages attached as strap on boosters. That would be quite an exciting aerial ballet with the two side boosters dropping off and doing a symmetric pirouette back to the launch site. We'd need to have another landing spot for the two boosters and then a third one for the center core. Although I think most of the Falcon Heavy missions will see the center core land on a ship most likely. It's really going ridiculously fast. The transfer energy of Falcon Heavy will more than double that of Falcon 9. The maximum transfer energy is approaching a terajoule.

Since, as I understand it, FH should be able to RTLS with pretty much all comsats, I can interpret this in three ways:

1. He expects comsat launches to account for less than 50% of FH launches, and the rest will be either really big or going to Mars.

2. He expects F9 barging to be cheaper than FH RTLS, so very few comsats will need FH (contrary to current manifest).

3. He's planning to deliver comsats to higher energy orbits, maybe even offering direct GEO insertion at a price that makes sense for customers besides the US government.

I find the third possibility most interesting, since it gives them an even stronger advantage than price alone vs. the competition. Plus, it's a nice market segmentation tool, which can help them remain profitable while lowering baseline prices to grow the market.

4. He's planning to use the extra performance to allow recovery of the upper stage. (More likely, extended tests with little hope of recovery in the early tests.)

There is a huge performance penalty for doing this on GTO missions. But, possibly, treated as an R&D project for recovering BFR MCTs, which will have a substantial tanking element.

Of course, Elon has said they have abandoned upper stage recovery for now, so this is less likely than your suggestions.

Cheers, Martin
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/08/2016 02:31 pm
SpaceX may retire Falcon Heavy before doing cross-feed. A large single-core vehicle like BFR may be more operationally efficient and could be fully reusable while getting a lot more payload.
BFR/BFS/MCT still looks to be 10 years out....
...[citation needed]

Typical aerospace project time. Of course, SpaceX isn't typical.
I hope you are right. I would love to see them produce the Raptor in 3 years and the BFR/MCT 3 years after that in 2022.
My point is that I see no citation that BFR is 10 years out. Musk suggested around 2020. If SpaceX is planning for BFR to be so close, they may steer whatever development resources that cross feed would take toward accelerating BFR instead, just like they seem to have done with the reusable upper stage. (This logic holds even if BFR eventually takes longer, because we're talking about SpaceX's plans & resource allocation decisions.)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/08/2016 02:33 pm
SpaceX may retire Falcon Heavy before doing cross-feed. A large single-core vehicle like BFR may be more operationally efficient and could be fully reusable while getting a lot more payload.
The fact is FHE (with side sticks RTLS and center booster expended) has more performance than pretty much any within earth orbit mission ordered worldwide and likely future missions.
And the number of missions that would require the center booster to be expended is tiny.
So this whole debate is ignoring the obvious extremely low likelyhood that SpaceX will actually need to iterate on FH cross feed.
Having an Eagle Lite type rocket will do everything FH can do, with both stages RTLS.
Yeah, that's my point.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/08/2016 04:34 pm
SpaceX may retire Falcon Heavy before doing cross-feed. A large single-core vehicle like BFR may be more operationally efficient and could be fully reusable while getting a lot more payload.
The fact is FHE (with side sticks RTLS and center booster expended) has more performance than pretty much any within earth orbit mission ordered worldwide and likely future missions.
And the number of missions that would require the center booster to be expended is tiny.
So this whole debate is ignoring the obvious extremely low likelyhood that SpaceX will actually need to iterate on FH cross feed.
Having an Eagle Lite type rocket will do everything FH can do, with both stages RTLS.
Yeah, that's my point.
Considering the way SpaceX does things in an incremental manner, we probably would not see crossfeed for at least 3 years and possibly as much as 6 years. SpaceX improvement cycle is currently averaging 2.5 years. The next item in improvement is reuse full scale (almost al flights reuse the boosters) such that prices drop by >30% over the current and possibly as much as 50%. If reuse eventually reduces the F9 price by $25M to $35M then the FH price over its expendable price whatever that is would reduce by $75M Or to put it more easily to only $10M more than the F9R price or $45M. This is what I see as their next improvement. Not so much a technological one but a revolutionary economic one. By the end of this year we may actually see the SpaceX pricing for reusable flights become the baseline with a delta extra charge to schedule for the first use or for use of the vehicle's full expendable capability.

Then in 6 years they will do something else to up the performance or introduce additional tech to lower the cost or turnaround time for the reusable boosters. What they will do even in 3 years from now is a guess. Although Raptor fits in there somewhere with it possibly going into full scale engine tests at around 2019. The earliest BFR testing would about 3 years after that 2022 with a dummy upper stage(MCT) to test the BFR by itself and hopefully recover the stage. Once that is accomplished then initial tests of the MCT: first just to get to  orbit and then successfully landing the stage back on Earth.

The real question about FH's future revolves around SpaceX's plans of it's use for their own purposes. Even that in the next 3 years is a question much less in 6 years. With SpaceX's history our crystal ball only extends just a few years out and even then is highly prone to errors. For something as far out as BFR/MCT even just Raptor which is at or greater than 3 years away, it is really tentative from the standpoint of what it will be and when it would occur.

Edit: The price values were in error ($10M to much if the price drops $25M).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Surfdaddy on 01/09/2016 07:25 pm
What if SpaceX wants to just recover a bunch of Falcon 9 cores, and then they have all these "free" cores to do with as they please? They could use them themselves for Mars exploratory/technology proving missions at relatively low cost, largely funded by their commercial business.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: clongton on 01/09/2016 07:58 pm
My point is that I see no citation that BFR is 10 years out. Musk suggested around 2020. If SpaceX is planning for BFR to be so close, they may steer whatever development resources that cross feed would take toward accelerating BFR instead, just like they seem to have done with the reusable upper stage. (This logic holds even if BFR eventually takes longer, because we're talking about SpaceX's plans & resource allocation decisions.)

Agree. At the time that cross feed was introduced in conjunction with the Falcon Heavy, the BFR didn't even exist conceptually. The cross-feed was supposed to increase the FH throw capability so that their "Heavy" could lift larger payloads. Given what we know now it is apparent that throttling the core engines can accomplish most (not all) that cross-feed could provide for virtually no additional expense. There is no documentation to back this up but everything I have seen to date indicates to me that BFR replaces FH with cross-feed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Semmel on 01/10/2016 12:37 am
Crossfeed made much more sense when the side boosters were larger than the core booster. However, that changed and with that change, crossfeed lost its biggest advantage. I think I remember that the side boosters are essentially F9 cores and the center core of the F9H is a specialized version that is stronger, they cant incrrease the size of the side boosters without creating a new production version of the boosters. That might be too expensive. If SpaceX decides that its worth the trouble to make the side boosters special, like making them larger, crossfeed might come back. Seems unlikely to me.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 01/10/2016 02:11 am
What if SpaceX wants to just recover a bunch of Falcon 9 cores, and then they have all these "free" cores to do with as they please? They could use them themselves for Mars exploratory/technology proving missions at relatively low cost, largely funded by their commercial business.

I'm pretty sure that's the plan.  Initially, they'll have more used cores than they can use for commercial purposes.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sdsds on 01/10/2016 05:56 am
Nine Merlin engines have now been recovered. But no Merlin engine has yet been recovered twice. I think SpaceX will change that quickly. It seems to me quite possible that the very first FH side boosters will each have one engine which has been previously flown.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/10/2016 03:26 pm
What we know:
1- M1D+ SL thrust 170klbf 15.6% more thrust
2- M1DVAC+ thrust 210klbf >15.6% more thrust with slight ISP increase due to longer nozzle
3- F9FT has 33% more performance than F9v1.1 ?(to LEO? to GTO?)
4- Denseified prop adds ~6.7% to prop load on 1st and 2nd stage combined which includes more volume on lengthened 2nd stage
5- 2nd stage has lengthened by ?(I could not find the exact value but it should be a known value) increaseing the prop volume by ?%
6- PF for 1st stage has increased (easily calculated for existing information and new weight and length measurements)
7- PF for 2nd stage has increased (easily calculated for existing information and new weight and length measurements)

What we don't know:
1- FHFT performance (all RTLS, booster's RTLS and center ASDS, booster's ASDS and center expended, all expended)
2- FHFT prices
3- 1st stage average refurbishment costs
4- 1st stage total incremental costs for a new booster (manufacturing, testing, shipping, and other misc before arrival at pad)
5- M1D+ engine life (average number of full duration burns without a rebuild+ average number of starts without a rebuild)
6- turnaround time (average time of total of refurbishment time and processing time [launch to launch])
7- stage life before rebuild or discard (number of allowable flights at about same reliability level)

What we think we know:
1- FHFT will not for foreseeable future (at least 3 years) use crossfeed
2- FHFT can provide the same performance that FHv1.1 with crossfeed could
3- FHFT can do all RTLS without significantly less performance than the FHv1.1 without crossfeed (normal usage low price heavy GTO mission)

Please add data or corrections where appropriate.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: alang on 01/10/2016 04:07 pm
Is it still possible that spacex could wait until they are ready to refly two used F9RFT first stages as side boosters before doing the Falcon heavy demo?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 01/10/2016 04:14 pm
Is it still possible that spacex could wait until they are ready to refly two used F9RFT first stages as side boosters before doing the Falcon heavy demo?

They need FH asap. They want to be able to fly all military payloads, meaning be certified, by the end of the block buy and that requires FH performance.

It seems the FH sideboosters and F9 core are mostly the same but not interchangeable. So they need boosters and prove reusability with F9, but they will reuse only FH side boosters for FH.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 01/10/2016 04:34 pm
I believe we've already seen the FH side boosters in the factory.  So they had to decide a while ago not to wait until landings were successful. (A good decision, in my book.)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 01/10/2016 04:49 pm
I remember seeing the unpainted caps for the boosters, but not the side cores assembled with them. Do you have a source for that (its an interesting subject)?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dave G on 01/10/2016 04:54 pm
A) It's not clear that FH can handle a fairing 2.3 times its core...
For larger objects, it may be possible to design a fairing that doesn't have circular cross section, looking down from the top.  This has been done before.  In fact, both the current and future Dragon capsules don't have circular cross sections.

For Falcon Heavy, I can imagine a PLF that is wider in the axis of the booster stages.  This could accommodate larger items, for example a Mars landing heat shield.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 01/10/2016 05:19 pm
I believe we've already seen the FH side boosters in the factory.  So they had to decide a while ago not to wait until landings were successful. (A good decision, in my book.)

If they want to fly the FH by the end of the first half of the year the first FH cores should be about ready to leave Hawthorne for McGregor.

I think many of us gloss over how much work the FH is than the F9.  There are similarities to be sure but the side boosters are longer, the core has to be structurally different to support the loads of the side boosters. 

I think that if April is to realistic those cores need to be making their way to McGregor very soon.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 01/10/2016 06:20 pm
If they want to fly the FH by the end of the first half of the year the first FH cores should be about ready to leave Hawthorne for McGregor.

I think many of us gloss over how much work the FH is than the F9.  There are similarities to be sure but the side boosters are longer, the core has to be structurally different to support the loads of the side boosters. 

I think that if April is to realistic those cores need to be making their way to McGregor very soon.

I agree that qualification of FH will be a complex process. Once that and the first flight is done I hope though that getting FH launch ready won't be too complex.

BTW the present version of FH has no extended cores on the side boosters. That has been abandoned to streamline production. It is shown in the latest animation.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Saabstory88 on 01/10/2016 06:50 pm

What we don't know:
1- FHFT performance (all RTLS, booster's RTLS and center ASDS, booster's ASDS and center expended, all expended)
2- FHFT prices
3- 1st stage average refurbishment costs
4- 1st stage total incremental costs for a new booster (manufacturing, testing, shipping, and other misc before arrival at pad)
5- M1D+ engine life (average number of full duration burns without a rebuild+ average number of starts without a rebuild)
6- turnaround time (average time of total of refurbishment time and processing time [launch to launch])
7- stage life before rebuild or discard (number of allowable flights at about same reliability level)

Please add data or corrections where appropriate.

8- Maximum atmospheric interface velocity of an F9 core which is survivable. Because they only have one type of upper stage, this number will determine the upper limit of the Falcon Heavy performance for standard payloads.

I imagine missions which expend the center core will be far more costly.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 01/10/2016 08:11 pm

What we don't know:
1- FHFT performance (all RTLS, booster's RTLS and center ASDS, booster's ASDS and center expended, all expended)
2- FHFT prices
3- 1st stage average refurbishment costs
4- 1st stage total incremental costs for a new booster (manufacturing, testing, shipping, and other misc before arrival at pad)
5- M1D+ engine life (average number of full duration burns without a rebuild+ average number of starts without a rebuild)
6- turnaround time (average time of total of refurbishment time and processing time [launch to launch])
7- stage life before rebuild or discard (number of allowable flights at about same reliability level)

Please add data or corrections where appropriate.

8- Maximum atmospheric interface velocity of an F9 core which is survivable. Because they only have one type of upper stage, this number will determine the upper limit of the Falcon Heavy performance for standard payloads.

I imagine missions which expend the center core will be far more costly.
Of all the possible hypothetical future mods, I think a stretched upper stage is near the top of the list.

Make sense to enlarge it if you're enlarging the first stage by 3:1 (effectively even more), and it also makes recovery easier.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/10/2016 08:55 pm

What we don't know:
1- FHFT performance (all RTLS, booster's RTLS and center ASDS, booster's ASDS and center expended, all expended)
2- FHFT prices
3- 1st stage average refurbishment costs
4- 1st stage total incremental costs for a new booster (manufacturing, testing, shipping, and other misc before arrival at pad)
5- M1D+ engine life (average number of full duration burns without a rebuild+ average number of starts without a rebuild)
6- turnaround time (average time of total of refurbishment time and processing time [launch to launch])
7- stage life before rebuild or discard (number of allowable flights at about same reliability level)

Please add data or corrections where appropriate.

8- Maximum atmospheric interface velocity of an F9 core which is survivable. Because they only have one type of upper stage, this number will determine the upper limit of the Falcon Heavy performance for standard payloads.

I imagine missions which expend the center core will be far more costly.
Of all the possible hypothetical future mods, I think a stretched upper stage is near the top of the list.

Make sense to enlarge it if you're enlarging the first stage by 3:1 (effectively even more), and it also makes recovery easier.
By going to 5m diameter for the US you can double the tank volume and only increase the tank weight by 50%. This not only increases the total propellant but also increases the effective PF far more than just the doubling of the stage scale. This increased size stage (no taller than the existing one) would greatly increase the high energy orbit payloads size.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 01/10/2016 09:14 pm

What we don't know:
1- FHFT performance (all RTLS, booster's RTLS and center ASDS, booster's ASDS and center expended, all expended)
2- FHFT prices
3- 1st stage average refurbishment costs
4- 1st stage total incremental costs for a new booster (manufacturing, testing, shipping, and other misc before arrival at pad)
5- M1D+ engine life (average number of full duration burns without a rebuild+ average number of starts without a rebuild)
6- turnaround time (average time of total of refurbishment time and processing time [launch to launch])
7- stage life before rebuild or discard (number of allowable flights at about same reliability level)

Please add data or corrections where appropriate.

8- Maximum atmospheric interface velocity of an F9 core which is survivable. Because they only have one type of upper stage, this number will determine the upper limit of the Falcon Heavy performance for standard payloads.

I imagine missions which expend the center core will be far more costly.
Of all the possible hypothetical future mods, I think a stretched upper stage is near the top of the list.

Make sense to enlarge it if you're enlarging the first stage by 3:1 (effectively even more), and it also makes recovery easier.
By going to 5m diameter for the US you can double the tank volume and only increase the tank weight by 50%. This not only increases the total propellant but also increases the effective PF far more than just the doubling of the stage scale. This increased size stage (no taller than the existing one) would greatly increase the high energy orbit payloads size.
Yup.

The stretch tank is less of a manufacturing/transport change, but clearly a wider tank is a better perspective former.  <-- auto corrupt.  Performer.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MikeAtkinson on 01/10/2016 09:16 pm
By going to 5m diameter for the US you can double the tank volume and only increase the tank weight by 50%. This not only increases the total propellant but also increases the effective PF far more than just the doubling of the stage scale. This increased size stage (no taller than the existing one) would greatly increase the high energy orbit payloads size.

I agree, but the diameter would be 5.2m (same as the fairing).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Danderman on 01/11/2016 03:53 am
Since it is a new year, let me repeat my prediction of several years ago, concerning FH:

There never will be a 50 ton version of this launcher.  At some point in the development of the FH, SpaceX will also develop larger engines and a new generation core stage, making FH obsolete. As such, FH will indeed fly some years down the road, but without the elaborate cross plumbed engines,  resulting in FH basically flying as a 27 engine Delta IV Heavy.

I would imagine soon after an initial launch of FH, SpaceX will already be focused on the follow-on, and FH will rarely fly.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 01/11/2016 04:25 am
Since it is a new year, let me repeat my prediction of several years ago, concerning FH:

There never will be a 50 ton version of this launcher.  At some point in the development of the FH, SpaceX will also develop larger engines and a new generation core stage, making FH obsolete. As such, FH will indeed fly some years down the road, but without the elaborate cross plumbed engines,  resulting in FH basically flying as a 27 engine Delta IV Heavy.

I would imagine soon after an initial launch of FH, SpaceX will already be focused on the follow-on, and FH will rarely fly.

Depending on how efficient reuse operations become, this includes the success rate DPL recovery.  I can see the FH flying often for Larger payloads with 3 cores RTLS.

I agree that the evolution of FH is likely limited.  Perhap US improvements and small tweaks (mostly to improve reuse ability) here and there but they will move onto ramping up production of F9s and FHs and that MethLOx stuff.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: woods170 on 01/11/2016 08:35 am
Since it is a new year, let me repeat my prediction of several years ago, concerning FH:

There never will be a 50 ton version of this launcher.  At some point in the development of the FH, SpaceX will also develop larger engines and a new generation core stage, making FH obsolete. As such, FH will indeed fly some years down the road, but without the elaborate cross plumbed engines,  resulting in FH basically flying as a 27 engine Delta IV Heavy.

I would imagine soon after an initial launch of FH, SpaceX will already be focused on the follow-on, and FH will rarely fly.
The nice thing about predictions is that they come with a 50 percent chance of becoming reality. On the other hand, the nice thing about predictions is that they come with a 50 percent chance of not becoming reality.
Time will tell what becomes of your prediction.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Bynaus on 01/11/2016 09:10 am
Quote
The nice thing about predictions is that they come with a 50 percent chance of becoming reality.

I predict that my next throw of a die will not yield a 6... Are you ready to pick up that bet at 1:1? :) Probability doesn't work that way. It's "successful outcomes divided by trials", but being "wrong" or "right" does not represent trials - in fact, there is only one trial (whatever the future actually holds), and in that future, either there will be many, or not so many FH flights, which might then be used to evaluate whether Danderman was right or not. But you cannot really assign a probability to that kind of prediction.

On an unrelated note, I agree with Danderman. A rocket that can potentially transport 100 passengers to Mars with 1 ton of cargo each, for 0.5 M$ per passenger (i.e., 500$/kg to Mars) will outcompete the FH (~2000 $/kg to LEO; likely lower with re-use, but even then) completely. When the BFR flies, it will be the end of the evolutionary line for F9 and FH. The question is of course how long it will take to go from FH to BFR, and whether having a FH during that time helps SpaceX to realize its Mars plans - the answer is yes, certainly (think military contracts, heavy GTO fully reusable, etc). So yes, the FH will fly, but only until the BFR comes along.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mader Levap on 01/11/2016 10:31 am
Quote
The nice thing about predictions is that they come with a 50 percent chance of becoming reality.

I predict that my next throw of a die will not yield a 6... Are you ready to pick up that bet at 1:1? :)
I think he was sarcastic.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Bynaus on 01/11/2016 10:39 am
Quote
The nice thing about predictions is that they come with a 50 percent chance of becoming reality.

I predict that my next throw of a die will not yield a 6... Are you ready to pick up that bet at 1:1? :)
I think he was sarcastic.

Ah, ok. We need a sacrasm sign for non-native english speakers. ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: woods170 on 01/11/2016 10:58 am
Quote
The nice thing about predictions is that they come with a 50 percent chance of becoming reality.

I predict that my next throw of a die will not yield a 6... Are you ready to pick up that bet at 1:1? :)
I think he was sarcastic.
That's a fact.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: tp1024 on 01/11/2016 11:11 am
Of all the possible hypothetical future mods, I think a stretched upper stage is near the top of the list.

Make sense to enlarge it if you're enlarging the first stage by 3:1 (effectively even more), and it also makes recovery easier.
By going to 5m diameter for the US you can double the tank volume and only increase the tank weight by 50%. This not only increases the total propellant but also increases the effective PF far more than just the doubling of the stage scale. This increased size stage (no taller than the existing one) would greatly increase the high energy orbit payloads size.

Or you could put regular 2nd stage tanks on top of the sideboosters too. (Think of 3 complete F9 side by side, with the payload being on the central one.) Then either crossfeed fuel to the center engine or equip the side tanks/booster with engines too. I don't think that the M1Vac can deal with accelerating a 300-400ton mass after staging, with some 93tons of thrust.

Makes staging events much more complex, but you could use existing production and transport infrastructure.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 01/11/2016 02:02 pm
I have to shake my head at people that believe that the BFR will exist any time soon.  How long has it taken SpaceX to get the FH ready for maybe debuting this year?

F9FT eating into the FH's margins is definitely a thing and a more reasonable reason to think the FH will play a less important role in SpaceX's fleet.  But it won't be replaced for quite some time.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 01/11/2016 02:19 pm
I have to shake my head at people that believe that the BFR will exist any time soon.  How long has it taken SpaceX to get the FH ready for maybe debuting this year?

F9FT eating into the FH's margins is definitely a thing and a more reasonable reason to think the FH will play a less important role in SpaceX's fleet.  But it won't be replaced for quite some time.

I agree that FH won't be replaced for some time... or be replaced ever as long as F9 is flying. Also believe that it will fly a lot.  Shotwell agrees, by the way, as her past statements about FH's role in Mars preps.  Fuel transport is the obvious niche...

But I'm also in that unbelievable group that thinks BFR will exist 'soon' as long as you allow soon to be defined as the next 5-6 years.  FH's work may be cut into by BFR some day as Mars effort ramps up, but I expect FH doing a big job for the next decade or more.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Craig_VG on 01/11/2016 03:57 pm
I have to shake my head at people that believe that the BFR will exist any time soon.  How long has it taken SpaceX to get the FH ready for maybe debuting this year?

F9FT eating into the FH's margins is definitely a thing and a more reasonable reason to think the FH will play a less important role in SpaceX's fleet.  But it won't be replaced for quite some time.

I think it's important to realize that the length of time it took to get FH to flight is not comparable to BFR. Here's why:

FH is completely dependant on the performance and reusability evolution of F9. It didn't pay to launch FH until the design of the F9 was more or less finalized. SpaceX's original announcement was premature as they kept finding ways to improve the single stick.

I think you can compare the BFR to the original F9 development.

BFR is an end for SpaceX. It's the essential element to achieve the goal of the company. They will prioritize its development.

Correct me if I'm wrong, though.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: DigitalMan on 01/11/2016 04:04 pm
I have to shake my head at people that believe that the BFR will exist any time soon.  How long has it taken SpaceX to get the FH ready for maybe debuting this year?

F9FT eating into the FH's margins is definitely a thing and a more reasonable reason to think the FH will play a less important role in SpaceX's fleet.  But it won't be replaced for quite some time.

I think it's important to realize that the length of time it took to get FH to flight is not comparable to BFR. Here's why:

FH is completely dependant on the performance and reusability evolution of F9. It didn't pay to launch FH until the design of the F9 was more or less finalized. SpaceX's original announcement was premature as they kept finding ways to improve the single stick.

I think you can compare the BFR to the original F9 development.

BFR is an end for SpaceX. It's the essential element to achieve the goal of the company. They will prioritize its development.

Correct me if I'm wrong, though.

Also, Gwynne had testified that FH had been put on the back burner for some period of time.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 01/11/2016 04:22 pm
I think it's important to realize that the length of time it took to get FH to flight is not comparable to BFR. Here's why:

FH is completely dependant on the performance and reusability evolution of F9. It didn't pay to launch FH until the design of the F9 was more or less finalized. SpaceX's original announcement was premature as they kept finding ways to improve the single stick.

I think you can compare the BFR to the original F9 development.

BFR is an end for SpaceX. It's the essential element to achieve the goal of the company. They will prioritize its development.

Correct me if I'm wrong, though.

I believe we are in full agreement. I would formulate it a bit different though.

Up to now there was no urgent need for FH. Building a 1.1 FH would take away cores for single launches. Instead they developed FT and first stage landing. Now they have that they ramp up core production and build FH. Building a 1.1 FH would mean they now have to develop a significantly different FH. The need now is for the DOD, for their own Mars ambitions, sending Red Dragon. And for launching even the heaviest commercial payloads in reusable mode.

Edit: Which means the reasons for delaying FH don't apply for BFR/MCT. I too expect to see it in a 5 year timeframe.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/11/2016 05:23 pm
I think it's important to realize that the length of time it took to get FH to flight is not comparable to BFR. Here's why:

FH is completely dependant on the performance and reusability evolution of F9. It didn't pay to launch FH until the design of the F9 was more or less finalized. SpaceX's original announcement was premature as they kept finding ways to improve the single stick.

I think you can compare the BFR to the original F9 development.

BFR is an end for SpaceX. It's the essential element to achieve the goal of the company. They will prioritize its development.

Correct me if I'm wrong, though.

I believe we are in full agreement. I would formulate it a bit different though.

Up to now there was no urgent need for FH. Building a 1.1 FH would take away cores for single launches. Instead they developed FT and first stage landing. Now they have that they ramp up core production and build FH. Building a 1.1 FH would mean they now have to develop a significantly different FH. The need now is for the DOD, for their own Mars ambitions, sending Red Dragon. And for launching even the heaviest commercial payloads in reusable mode.

Edit: Which means the reasons for delaying FH don't apply for BFR/MCT. I too expect to see it in a 5 year timeframe.
FH life is indeed tied to the arrival of BFR/MCT.

But the arrival of BFR/MCT is directly tied to the engine work on Raptor. Once Raptor proceeds into full scale engine testing. There may be several iterations each an improvement of thrust and ISP but these will be optimizations of the design and not real redesigns occurring in this initial testing over a short period maybe even less than a year. But the vehicle designs are all at the mercy of having an actual predictable end point design of the Raptor's physical characteristics. Until that point which will be shortly after full scale testing begins, the vehicle designs will rapidly take on a more exacting physical form vs the mathematical concepts until the Raptor is defined. So the crystal ball is such that several years after Raptor reaches its full scale testing a vehicle for a first flight test will show up depending on available reinvestment funding. The more available funds the shorter the time span up to a point (probable minimum is 2 years, max would be 5 years if funding is minimal).

So the basic question on BFR/MCT arrival onto the scene is when will Raptor arrive on the scene? There are some questins that have to be answered before MCT can be designed such as the Raptor performance in a hyper-velocity burn both in an Earth reentry and in a Mars atmosphere entry. FH could be used to lift a prototype scale test vehicle with a single Raptor to test the concepts and gather hard data. The time frame between a Raptor existence and the MCT existence may be longer than most realize. But the timeframe between Raptor and BFR may be short indeed. With an interim expendable US design that vehicle would put any HLLV system currently in existence or being designed out of work (180mt-210mt to LEO but with only 1st stage reuse).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 01/11/2016 05:34 pm
I agree FH took longer than it had to, because SpaceX didn't really "need" it until now, and the F9 was a moving target.  I also think it took longer because SpaceX is fully committed with everything else they are doing.  It is also fair to say that FH is much easier to develop than BFR will be.

5-6 years till first launch of BFR... let's call it January 2022... seems very optimistic to me.  Let me ask a few honest questions:

-When do people see Raptor being fully qualified?
-When do people see an EIS for a site that can launch a BRF approved?
-When do people see a launch site that can launch BFR developed?

Keep in mind:
-Raptor (from public info) appears to be still in pretty early development
-Boca Chica hasn't even broke ground yet.
-SpaceX is focused on
1) Catching up on their F9 backlog.
2) Barge landing
3) Stage reuse
4) Finishing up 39A
5) Falcon Heavy debut
6) CRS2 (likely to be some changes to their offering from CRS)
7) DragonV2 / Commercial Crew
8\) Boca Chica developed and brought online
9) ConstellationX
10) ? (probably missing at least one thing here)

Most of up through 7 should be basically complete by end of '17.  I imagine Raptor will be CDR and the initial version will be design frozen.  I think Boca Chica comes online in '18.  Even then we're talking four years to build, test, and fully qualify Raptor, build the rocket, secure an EIS for and build the launch site, etc, all while the rest of the business is operating at a launch rate not seen since the Soviets in the 80's.  While reusing 1st stages, and spending a lot of time improving and automating their work flow to even be able to achieve such a rate in the first place.

And, oh yeah, that assumes everything goes right and there are no setbacks.  Difficulty developing Raptor (which would not be surprising), difficulty securing a launch site for BFR, difficulty in just launching "boring" F9 and FH, etc.

Seems like a very tall order.  If in 5-6 years SpaceX has done all that, established a new BFR launch site, and launched a BFR, I will be astonished.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RoboGoofers on 01/11/2016 06:41 pm
Seems like a very tall order.  If in 5-6 years SpaceX has done all that, established a new BFR launch site, and launched a BFR, I will be astonished.

Furthermore, will they launch a BFR without qualifying it can land? if not, they'll need a Grasshopper 2 test program. And also an MTC landing test. They'll probably want Dragon 2 fully propulsive landing with people in it before they launch an MTC.

(edit: Oh and pad and inflight abort for MTC)

I just don't think that'll happen before 2025.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 01/11/2016 07:12 pm
...Up to now there was no urgent need for FH. Building a 1.1 FH would take away cores for single launches. Instead they developed FT and first stage landing. Now they have that they ramp up core production and build FH. Building a 1.1 FH would mean they now have to develop a significantly different FH. The need now is for the DOD, for their own Mars ambitions, sending Red Dragon. And for launching even the heaviest commercial payloads in reusable mode.

Edit: Which means the reasons for delaying FH don't apply for BFR/MCT. I too expect to see it in a 5 year timeframe.

I think the original reasoning for FH was likely chasing the largest defense payloads and the mega paydays those provide.  Profit from 1 defense FH launch is probably equal to 10 commercial launches.

Now it looks to be the fully reuseable first stage for larger Commsats. 

The day dream of Red Dragon and Mars all need to be backseat to those endeavors that generates profit.

Edit: Regarding Raptor, I can see it spending far more time on the test stand and being developed and tested exhaustively.  When Raptor and the vehicle it powers first flies we'll see a more mature product than the Merlin 1. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Hotblack Desiato on 01/13/2016 08:45 am
I'm not so sure about FH being obsolete when BFR enters the stage.

Imagine some DOD-payload that needs to be brought onto a polar orbit (spy sats love being in polar orbits). Currently only vandenberg is equipped for polar orbit launches (as not stage would fall into inhabited areas. True, some day in the future, when BFR is so reliable that they can risk it (and a BFR first stage crash is as likely as a commercial plane crash), they can risk doing a polar orbit from cape canaveral or boca chica, but until then, they are restricted to vandenberg.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 01/13/2016 12:36 pm
Regarding Raptor, I can see it spending far more time on the test stand and being developed and tested exhaustively.  When Raptor and the vehicle it powers first flies we'll see a more mature product than the Merlin 1.

I agree, they will need a very well developed Raptor, though they will probably still improve it over time with experience. That's why I don't expect Raptor to be ready before 2018/19. Don't underestimate, how far along they already are. We know that the two most critical components already have been tested at full scale. The oxygen rich preburner and the main combustion chamber injector. Actually I would not be too surprised if we see the first full scale development test engine this year or early next year.

The most critical element is building permit for the launch pad. That will control the timing.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 01/13/2016 01:54 pm
They might not launch BFR from land, but on a large offshore platform.  Liquid natural gas can be piped from land to the pad offshore as well as LOX, or they can use an LNG ship to fuel the rocket.  From a few hundred yards to a few miles offshore in the shallow Gulf of Mexico offshore Texas would be much easier.  It could even be in international waters thus avoiding all the red tape from the Feds.  The platform could be anchored in the gulf and built like the giant platforms used in the North Sea. 

I know this is a FH discussion thread, but FH can send payloads to Mars.  Depending on how SLS pans out, NASA might use FH with a hydrolox upper stage for deep space probes or Mars work, and that would depend on Vulcan's time table.  If SLS becomes too expensive, NASA can build, design, and with in space assembly, a Mars or moon manned operation with 40-50 ton pieces with money saved from SLS.  Fuel depots, SEP transfers, landing equipment etc could be built and launched with money saved from SLS by FH an Vulcan with much lower launch costs. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dave G on 01/13/2016 02:20 pm
They might not launch BFR from land, but on a large offshore platform.
Why did SpaceX choose South Texas for their new commercial launch site?  Puerto Rico is much closer to the equator, and they wouldn't need to worry about flying over Florida or Cuba (i.e. no need for dogleg flight profile).  The answer: It's more expensive to ship things to Puerto Rico. 

Same for BFR.  They will launch BFR from a land-based site within the continental U.S. to minimize costs.

I know this is a FH discussion thread, but FH can send payloads to Mars.  Depending on how SLS pans out, NASA might use FH with a hydrolox upper stage for deep space probes or Mars work, and that would depend on Vulcan's time table.  If SLS becomes too expensive, NASA can build, design, and with in space assembly...
Earth orbit "assembly" conjures up a lot of negative connotations.  Most people think of assembly as something that would take months or years in earth orbit, making it very costly. 

So I would call it "docking plus a few EVAs" before TMI. 

But yes, I agree that multiple FH flights could be used to for a Mars mission, and this has been discussed in detail in various papers and other threads here.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 01/13/2016 03:05 pm
It could even be in international waters thus avoiding all the red tape from the Feds. 

I don't know, can you legally launch American crewed spacecraft from international waters? American ever-so-faintly-ICBM-like projectiles from international waters? American LVs?

What was the legislature Sea Launch operated under and would that apply here? If I was on capitol hill I can imagining myself bustling to get it to launch from US waters, for whatever reason I may have, politically or practically motivated. It'd be like launching Saturn 5 from international waters.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: HMXHMX on 01/13/2016 05:11 pm
It could even be in international waters thus avoiding all the red tape from the Feds. 

I don't know, can you legally launch American crewed spacecraft from international waters? American ever-so-faintly-ICBM-like projectiles from international waters? American LVs?

What was the legislature Sea Launch operated under and would that apply here? If I was on capitol hill I can imagining myself bustling to get it to launch from US waters, for whatever reason I may have, politically or practically motivated. It'd be like launching Saturn 5 from international waters.

There is no prohibition in place, but there is also no exemption from any regulation or law for a US-person-owned firm conducting launch operations at sea (see for example, SeaLaunch, which had to obtain FAA-AST launch licenses).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 01/13/2016 05:55 pm
I still say due to the sound problems associated with a 15 m wide 15 million lb thrust rocket, over water is better.  The Gulf of Mexico is very shallow.  I've bottom fished beyond the sight of land offshore.  An oil platform with crane coupled with a barge bringing out the BFR would make it easy over water.  The Boca Chica site will probably still be used to land the BFR as well as F9 and FH boosters.  Either way the BFR cannot be shipped by any other means than barge to a launch site due to shear size.  Unless the factory itself is onshore, with a ramp to carry it out to a launch platform, like the bridges going to Key West.  The Key West bridge originally carried a railroad train, which is probably heavier than an unfueled BFR. 

Sea Dragon was supposed to launch a 20-25m rocket directly off the ocean to give 500 tons to LEO. 

I do think that Boca Chica is only another FH/F9 launch site.  SpaceX with hundreds of internet satelites they plan to launch, is expecting a lot of F9/FH launches, thus needing the extra launch sites. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Donosauro on 01/13/2016 06:26 pm
It could even be in international waters thus avoiding all the red tape from the Feds. 

I don't know, can you legally launch American crewed spacecraft from international waters? American ever-so-faintly-ICBM-like projectiles from international waters? American LVs?

What was the legislature Sea Launch operated under and would that apply here? If I was on capitol hill I can imagining myself bustling to get it to launch from US waters, for whatever reason I may have, politically or practically motivated. It'd be like launching Saturn 5 from international waters.

There is no prohibition in place, but there is also no exemption from any regulation or law for a US-person-owned firm conducting launch operations at sea (see for example, SeaLaunch, which had to obtain FAA-AST launch licenses).

Not even from the need for an EIS?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: HMXHMX on 01/13/2016 06:33 pm
It could even be in international waters thus avoiding all the red tape from the Feds. 

I don't know, can you legally launch American crewed spacecraft from international waters? American ever-so-faintly-ICBM-like projectiles from international waters? American LVs?

What was the legislature Sea Launch operated under and would that apply here? If I was on capitol hill I can imagining myself bustling to get it to launch from US waters, for whatever reason I may have, politically or practically motivated. It'd be like launching Saturn 5 from international waters.

There is no prohibition in place, but there is also no exemption from any regulation or law for a US-person-owned firm conducting launch operations at sea (see for example, SeaLaunch, which had to obtain FAA-AST launch licenses).

Not even from the need for an EIS?

Nope: https://www.faa.gov/about/office_org/headquarters_offices/ast/media/final_ea_sea_launch.pdf
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/13/2016 08:52 pm
They might not launch BFR from land, but on a large offshore platform.
Why did SpaceX choose South Texas for their new commercial launch site?  Puerto Rico is much closer to the equator, and they wouldn't need to worry about flying over Florida or Cuba (i.e. no need for dogleg flight profile).  The answer: It's more expensive to ship things to Puerto Rico. 

Same for BFR.  They will launch BFR from a land-based site within the continental U.S. to minimize costs.
.,..
Nope, we don't know that. Neither does SpaceX. And we know SpaceX is looking beyond continental US.

This is not Falcon 9, we won't be transporting by road. The same assumptions do not apply.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mvpel on 01/15/2016 06:08 pm
They might not launch BFR from land, but on a large offshore platform.
Why did SpaceX choose South Texas for their new commercial launch site?  Puerto Rico is much closer to the equator, and they wouldn't need to worry about flying over Florida or Cuba (i.e. no need for dogleg flight profile).  The answer: It's more expensive to ship things to Puerto Rico. 

... in more ways than one:

How to Put a Stop to Puerto Rico's Political Corruption (http://blog.panampost.com/frank-worley-lopez/2015/12/09/how-to-put-a-stop-to-puerto-ricos-political-corruption/) - December 9, 2015
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: alang on 01/24/2016 03:01 pm
Given the pressure on the launch schedule, the performance of f9FT,the possibility of a raptorish upper stage implied by the recent contract award, the expressed view that a single stick BFR is better than one with side boosters, slower progress on stage return, BO's progress with methane etc. Is it possible that the heavy will be cancelled and all effort put into raptor variants for both f9 improvement and BFR acceleration.
I doubt that elon musk is likely to fall victim to the fallacy of the sunk cost.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: deltaV on 01/24/2016 03:38 pm
Given the pressure on the launch schedule, the performance of f9FT,the possibility of a raptorish upper stage implied by the recent contract award, the expressed view that a single stick BFR is better than one with side boosters, slower progress on stage return, BO's progress with methane etc. Is it possible that the heavy will be cancelled and all effort put into raptor variants for both f9 improvement and BFR acceleration.
I doubt that elon musk is likely to fall victim to the fallacy of the sunk cost.

SpaceX needs Falcon Heavy to serve many of their customers. The customers wouldn't like waiting for Raptor and SpaceX's bank account wouldn't appreciate the delay either. I would only expect to see Falcon Heavy canceled if a critical flaw is discovered in its design.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: su27k on 01/24/2016 03:42 pm
Given the pressure on the launch schedule, the performance of f9FT,the possibility of a raptorish upper stage implied by the recent contract award, the expressed view that a single stick BFR is better than one with side boosters, slower progress on stage return, BO's progress with methane etc. Is it possible that the heavy will be cancelled and all effort put into raptor variants for both f9 improvement and BFR acceleration.
I doubt that elon musk is likely to fall victim to the fallacy of the sunk cost.

They need FH for precursor Mars missions.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 01/24/2016 03:48 pm
IMO the most pressing reasons to get Falcon Heavy flying are two. One is getting Red Dragon to Mars, but he might be willing to put that off 2-3 years. Even more important he wants to be able to compete the whole range of DOD payloads. Gwynne Shotwell has stated in a Congress Hearing that they want Falcon Heavy to be certified by 2018. That means it must fly 2016.

Falcon 9 in expendable mode will cover near 100% of commercial customer needs and be very competetive.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/24/2016 07:10 pm
Given the pressure on the launch schedule, the performance of f9FT,the possibility of a raptorish upper stage implied by the recent contract award, the expressed view that a single stick BFR is better than one with side boosters, slower progress on stage return, BO's progress with methane etc. Is it possible that the heavy will be cancelled and all effort put into raptor variants for both f9 improvement and BFR acceleration.
I doubt that elon musk is likely to fall victim to the fallacy of the sunk cost.

SpaceX needs Falcon Heavy to serve many of their customers. The customers wouldn't like waiting for Raptor and SpaceX's bank account wouldn't appreciate the delay either. I would only expect to see Falcon Heavy canceled if a critical flaw is discovered in its design.
I think Falcon Heavy will eventually go the way of Falcon 1 and Falcon 9 v1.1. But not for many years.

As far as critical flaw, having more staging events does increase risk somewhat and is more complicated operationally. And methane/LOx would allow easier/faster turnaround. So not "critical" flaws, but long-term, they'll probably go beyond Falcon Heavy.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 01/25/2016 12:37 am
Just a reminder, FH will be the world's largest operational launcher for the next 5-10 years, and the world's lowest price for a kg to orbit.  Ever.  Flaws or no, it won't be easily brushed aside.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 01/25/2016 01:13 am
It's going to need to do a Post-Soviet Proton for its advantages to be overlooked. It's certainly going to hurt Arianespace.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: BobHk on 01/25/2016 03:07 am
I still say due to the sound problems associated with a 15 m wide 15 million lb thrust rocket, over water is better.  The Gulf of Mexico is very shallow.  I've bottom fished beyond the sight of land offshore.  An oil platform with crane coupled with a barge bringing out the BFR would make it easy over water.  The Boca Chica site will probably still be used to land the BFR as well as F9 and FH boosters.  Either way the BFR cannot be shipped by any other means than barge to a launch site due to shear size.  Unless the factory itself is onshore, with a ramp to carry it out to a launch platform, like the bridges going to Key West.  The Key West bridge originally carried a railroad train, which is probably heavier than an unfueled BFR. 

Sea Dragon was supposed to launch a 20-25m rocket directly off the ocean to give 500 tons to LEO. 

I do think that Boca Chica is only another FH/F9 launch site.  SpaceX with hundreds of internet satelites they plan to launch, is expecting a lot of F9/FH launches, thus needing the extra launch sites.

Shotwell explicitly indicated they'd build BFR on the launch site.  So shipping it is very unlikely.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Star One on 01/25/2016 06:29 am

Just a reminder, FH will be the world's largest operational launcher for the next 5-10 years, and the world's lowest price for a kg to orbit.  Ever.  Flaws or no, it won't be easily brushed aside.

Words are easy, actions more difficult, reality different again.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/25/2016 02:39 pm
Maybe the revelations about LV's to be released this year will contain new FH performance and pricing info, maybe including FH with Raptor (possibly even a animation of Raptor US recovery).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 01/25/2016 03:22 pm
Just a reminder, FH will be the world's largest operational launcher for the next 5-10 years, and the world's lowest price for a kg to orbit.  Ever.  Flaws or no, it won't be easily brushed aside.

It's great to see such positive comments and I really appreciate your enthusiasm, but I would have to note that it may be overly ambitious to have such enthusiasm over a rocket that is yet to fly.

Edited by the PoliteJim2000 app
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mule169 on 01/25/2016 07:40 pm
Just a reminder, FH will be the world's largest operational launcher for the next 5-10 years, and the world's lowest price for a kg to orbit.  Ever.  Flaws or no, it won't be easily brushed aside.

It's great to see such positive comments and I really appreciate your enthusiasm, but I would have to note that it may be overly ambitious to have such enthusiasm over a rocket that is yet to fly.

Edited by the PoliteJim2000 app
made me chuckle.  I like the un-appified Jim better though.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Hotblack Desiato on 01/25/2016 07:57 pm
Just a reminder, FH will be the world's largest operational launcher for the next 5-10 years, and the world's lowest price for a kg to orbit.  Ever.  Flaws or no, it won't be easily brushed aside.

It's great to see such positive comments and I really appreciate your enthusiasm, but I would have to note that it may be overly ambitious to have such enthusiasm over a rocket that is yet to fly.

Edited by the PoliteJim2000 app

I think, a very important part will be bumping the recovery rate over 66%, otherwise it is pointless to switch from a F9 in expendable mode to a FH in fully reusable mode (without the upper stage). Just because at a recovery rate of 66%, one stage is quite likely to be lost, maybe even two, whereas a F9 expendable is lost, by definition (Musk currently expects a landing-successrate of 70%, but who knows, what it is in reality).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 01/25/2016 08:44 pm
He said he expects 70% this year, 90% next year and increasing after that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 01/25/2016 09:47 pm
I think, a very important part will be bumping the recovery rate over 66%, otherwise it is pointless to switch from a F9 in expendable mode to a FH in fully reusable mode (without the upper stage). Just because at a recovery rate of 66%, one stage is quite likely to be lost, maybe even two, whereas a F9 expendable is lost, by definition (Musk currently expects a landing-successrate of 70%, but who knows, what it is in reality).

A couple of comments on this train of thought:

1st) if the recovery rates for FH cores are all equal (RTLS or ASDS) and the costs to launch a recoverable FH are equal to the costs to launch an expendable F9 then that 67% would be true, but we know that an expendable F9 costs less to launch (no legs, no grid fins, no associated preflight effort with them, lower propellant costs, maybe lower site costs) - that might up the percentage to 75 or 80% needed to justify using the FH3R. But if the recovery rate for side boosters doing RTLS is 95% and ASDS centre core recovery is 50% that leaves better odds that all cores are recovered than if each core had a 70% recovery rate.

2nd) your scenario only addresses the instances where the payload could be launched on a F9 expendable successfully, there is a class of payloads that don't fit the F9 expendable category at all but could be launched with an FH3R, even more that could go on an FH2R and finally the largest set are ones that could go on an expendable FH.  Those 3 categories may not make up even half the payloads that SpaceX launches some year in the more distant future, but they actually only have to represent 25% of the total payloads for them to represent the need to launch just as many FH cores as F9 cores so feeding that need with cores makes it as demanding as the F9 activities at just 25% of all payloads.

3rd) There is no payload advantage over an F9 RTLS if you try to launch an FH and bring all 3 cores back to the launch site unless you up the mass of the 2nd stage.  This means that an FH that tries to bring all 3 cores back to the launch site has a lower capacity than an F9 expendable or even an ASDS recovery. So RTLS of all 3 cores on an FH will not be done for economic reasons ever without a new S2.

4th)There is very little payload advantage in recovering the side boosters down range over RTLS presuming that you are throttling down the centre core and shutting down engines before side booster separation. So, presuming that RTLS has even a marginally higher recovery rate than ASDS, it will always be advantageous to bring the side boosters back to the launch site.

5th)That leaves three FH configurations to discuss as having any economic value: fully expendable, side booster RTLS centre core expendable, and side booster RTLS centre core ASDS.  Realistically when you consider what a booster cores contribution to the total cost of the flight it is quite likely that on a per kg basis centre core expendable is a lower price per kg for BLEO destinations than F9R and that recovering the centre core may be cheaper per kg than throwing it away for LEO payloads. Fully expendable FH launches will be reserved for the highest energy requirements that just can't be met with any other configuration (beyond GTO, possibly beyond GEO even) while there theoretically could be payloads with a mass that would force the use of an FH fully expendable to LEO, GTO or GEO on a per kg basis those missions would be more expensive than the other configuration would be.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Hotblack Desiato on 01/25/2016 11:38 pm
@nadreck:

1.) 2.) I specifically addressed the case of using a FHR as a replacement of a F9 (Expendable). I do know, that there is still the possiblilty that a payload requires a launch on a FH, because a F9 (E) is to weak. We don't know yet what the recovery rate will look like. so far, the landings on barges weren't terribly successful, but I'm optimistic that that will change.
It is a little advantage not having gridfins and legs on board, especially if they are not used anyways.

3.) Replacing a F9R-launch with a FHR-launch is pointless, as you said, there is no real advantage. Having a FH in 3x RTLS mode should be better for some orbits, but I think, that the center stage has to land on the ASDS.

4.) 5.) Quite an interesting thought. There are 2 more possibilities. Currently, one ASDS is on the east coast, and the other one is on the west coast. Both ASDS could be placed on the east coast, receiving the side stages, whereas the center stage is expended. Should boost the capacity aswell.

Regarding FH 3x RTLS, I don't know yet how good that works, but I expect it to be at least a bit better than a F9 RTLS, and en par with a a F9 (E). But I don't have solid numbers on that, maybe somebody else can help with that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 01/26/2016 12:23 am
Hotblack back in September I worked out a set of spreadsheets to calculate the performance of the FH based on 1.1 cores and the then standard S2. If I get good numbers to replace those with FT assumptions. But the difference between RTLS and down range on the side cores is about 400m/s.

http://forum.nasaspaceflight.com/index.php?topic=36806.msg1423023#msg1423023 (http://forum.nasaspaceflight.com/index.php?topic=36806.msg1423023#msg1423023)

and with an updated set of worksheets that allow you to evaluate it with crossfeed as well (I don't see them doing cross feed, but it was asked for and it does enhance performance)

http://forum.nasaspaceflight.com/index.php?topic=36806.msg1423270#msg1423270 (http://forum.nasaspaceflight.com/index.php?topic=36806.msg1423270#msg1423270)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 01/26/2016 01:49 am
I hope they can get the Raptor upper stage with a 5.2m diameter for heavier payloads.  From fully reusable to 80+ tons expendable.  This without a BFR.  SpaceX might consider building a large NautilusX type craft for travel to and from Mars.  Use F9 to ferry crews and passengers to it, especially using Bigelow modules.  At first the craft will ferry a lot of cargo with reusable Mars landers, solar panels and ISRU fuel capabilities, with smaller crews to operate.  Then later ferry more equipment.  Several of these NautilusX type craft could be built for continuous ferries between Earth and Mars, maybe like Buz Aldrin's cyclers.  Maybe using SEP thrusters. 

I know what he said about all in one big BFR/MCT.  But a good Mars program could start with FH with a good Raptor upper stage.  At least a Mars communication system built at Mars GSO. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 01/26/2016 02:12 am
But a good Mars program could start with FH with a good Raptor upper stage.

You are more right than you know.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 01/26/2016 03:17 am
When F9 Heavy was first scheduled for flight in 2013, it was baselined using the Merlin 1-C and a much smaller S1 core & propellant load.  As the Merlin has evolved to much higher performance and the core stretched to take advantage of that, I think is arguable to consider that the size of the side cores should be getting smaller, not larger.  It begs the question, what is the end purpose of building a rocket?   To make something spectacular on paper, or something that will actaully fly often?   All that extra mass, engine count, and costly downrange deltaV maneuvering  of FH could be reduced with smaller side boosters that stage earlier, & can be re-used.

Falcon Heavy as currently configured has pushed it's payload capacity beyond most anything that is scheduled to be launched, or likely to ever be launched, so what then is going to make it a "success"?   At best, it splits the competition for heavy DoD launches against Delta IV, that alone may make it a commercial success.  The other valid mission is to give extra margin to start re-use testing on stage 2.

It is a strong argument that re-usability and low cost need a high flight rate to enable both objectives.   FH seems positioned to fall short of sustaining a high flight rate.  Even if RTLS or ASDS of F9 single stick rockets put SpaceX in a position of having a few dozen available cores in 12-24 months, are the LEO and GTO paying customers going to want to put their less than 17 tons to LEO or 5.5 ton to GTO sats on a rocket with 28 engines so that SpaceX can test S2 reusability?   F9 FT already has that sweet spot in the market well covered with RTLS or downrange landing for S1, so that kills or very substantially reduces the potential for FH to have a high flight rate anytime soon.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 01/26/2016 06:10 am
When F9 Heavy was first scheduled for flight in 2013, it was baselined using the Merlin 1-C and a much smaller S1 core & propellant load.  As the Merlin has evolved to much higher performance and the core stretched to take advantage of that, I think is arguable to consider that the size of the side cores should be getting smaller, not larger.  It begs the question, what is the end purpose of building a rocket?   To make something spectacular on paper, or something that will actaully fly often?   All that extra mass, engine count, and costly downrange deltaV maneuvering  of FH could be reduced with smaller side boosters that stage earlier, & can be re-used.

Are you completly forgetting the economic benefit of building cores that are the same size? And that the side cores are basically F9 cores? The point is to get something that is cost effective.

Falcon Heavy as currently configured has pushed it's payload capacity beyond most anything that is scheduled to be launched, or likely to ever be launched, so what then is going to make it a "success"?   At best, it splits the competition for heavy DoD launches against Delta IV, that alone may make it a commercial success.  The other valid mission is to give extra margin to start re-use testing on stage 2.

No, the extra margin is to allow first stage (and booster) reuse. If the the extra performance allows all three cores to RTLS - and refurbishment is cost effective - than that is a big win for SpaceX.

Stop thinking in the "optimize for performance" mindset. You won't understand SpaceX that way... They are optimizing for cost. One size core, one size upper stage, one size fairing. What else is there to understand?
(And should they start using a Raptor based upper stage, the other benefits will remain, thus reducing booster size would be counter-productive)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 01/26/2016 07:53 am
When F9 Heavy was first scheduled for flight in 2013, it was baselined using the Merlin 1-C and a much smaller S1 core & propellant load.  As the Merlin has evolved to much higher performance and the core stretched to take advantage of that, I think is arguable to consider that the size of the side cores should be getting smaller, not larger.  It begs the question, what is the end purpose of building a rocket?   To make something spectacular on paper, or something that will actaully fly often?   All that extra mass, engine count, and costly downrange deltaV maneuvering  of FH could be reduced with smaller side boosters that stage earlier, & can be re-used.

Are you completly forgetting the economic benefit of building cores that are the same size? And that the side cores are basically F9 cores? The point is to get something that is cost effective.

Falcon Heavy as currently configured has pushed it's payload capacity beyond most anything that is scheduled to be launched, or likely to ever be launched, so what then is going to make it a "success"?   At best, it splits the competition for heavy DoD launches against Delta IV, that alone may make it a commercial success.  The other valid mission is to give extra margin to start re-use testing on stage 2.

No, the extra margin is to allow first stage (and booster) reuse. If the the extra performance allows all three cores to RTLS - and refurbishment is cost effective - than that is a big win for SpaceX.

Stop thinking in the "optimize for performance" mindset. You won't understand SpaceX that way... They are optimizing for cost. One size core, one size upper stage, one size fairing. What else is there to understand?
(And should they start using a Raptor based upper stage, the other benefits will remain, thus reducing booster size would be counter-productive)

I get what you are saying.  I see it put forward as a near unquestioned "given" everywhere.   I am not disagreeing just to play some devils advocate game.  I think that the benefits of maintaining a common core size work out great IF the flight rate is high for the configuration.    I don't see that possibility until the market completely changes, and that point of elasticity is found that dramatically increases the number of heavy payloads to be launched.  If I am wrong on that, smaller side boosters in comparison to high flight rate F9 core boosters lose.

I guess I would really need to know what the incremental cost to the 3.7 meter core production line is to maintain capability for the center core of FH to weigh against a smaller line for side boosters.   An interesting data point might be the cost of an F1 vs. F9 v1.0.   A smaller LRB might cost 1/4 to 1/3 of a F9 side core.   A smaller new booster would be like a F9 side core with 3-4 uses already amortized into it's cost at the outset. 

The performance loss for a quicker burning small booster, staging earlier, is also not as great as you would think.   So much of the FH side core performance is lost to the expensive energy requirement for RLTS that stages when the rocket is very high, and very far downrange.   It's generally non controversial & accepted that low efficiency is is high cost, and F9 side cores that RTLS are low efficiency from the standpoint of delivering maximum energy to the center core.

Smaller boosters aren't necessarily incompatible with the concept of enabling RTLS re-use for the booster itself, or the center core.   This is especially true for GTO launches that are just out of the reach of RTLS for F9 FT.  Smaller boosters could push a F9 FT past that important threshold for 6-7ton payloads to GTO with RLTS.  (guessing payloads greater than 5.5t, SES-9 will inform us better)  This would smash Ariane 6 & Vulcan in competition for heavier payloads without resorting to a full FH configuration.

As for S2 re-use & Raptor implementation, again going to available payloads, until the $$$ are being spent on big heavy payloads for Mars, the Moon or 3 lettered government agencies, the existing kerolox hardware has the job covered.   If anything, a FFSC Raptor or mini-raptor will have a worse T/W than Merlin Vac, so the empty weight of S2 is going to grow incrementally.   How much mass will have to be added to S2 for any re-use scheme?   Does that incremental mass justify a FH?   Is that viable to have a S2 for F9 FT that cuts 1:1 payload to GTO?  Even with the higher ISP of methalox, Probably not.   Which leaves a Raptor powered S2 a more likely configuration for a FH that can pay the dry mass penalty of S2.

By the way, since you are eager to see Raptor implemented on S2 configurations, you are now violating your espoused principals of simplicity.  I've added some "ones" to your list:   The "one core, one stage 2, one fairing, one engine, one fuel" principal on three counts ( fuel, one S2, multiple engine types) How deep is the commitment to just one of each? 

I respect the philosophy of optimizing for cost, not performance.  I would add that optimizing for profitability is also not incompatible for optimizing cost.   
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MP99 on 01/26/2016 08:23 am


But a good Mars program could start with FH with a good Raptor upper stage.

You are more right than you know.

It makes good economic sense to mature FH with as much commonality as possible. Booster size, no crossfeed, etc. Such a large and complex vehicle has enough risks of its own without adding to them.

AF seem to have a requirement for greater performance, and this can be added later with less risk and disruption.

If their Mars Ambitions include the performance of a Raptor upper stage, it would also make sense that they'd optimise the rest of the now-mature stack, IE crossfeed, larger side boosters, etc by that time.

Maybe even some wild and wacky ideas, such as using Merlin vac for one or two of the engines of the centre core.

Cheers, Martin
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 01/26/2016 09:24 am
When F9 Heavy was first scheduled for flight in 2013, it was baselined using the Merlin 1-C and a much smaller S1 core & propellant load.  As the Merlin has evolved to much higher performance and the core stretched to take advantage of that, I think is arguable to consider that the size of the side cores should be getting smaller, not larger.  It begs the question, what is the end purpose of building a rocket?   To make something spectacular on paper, or something that will actaully fly often?   All that extra mass, engine count, and costly downrange deltaV maneuvering  of FH could be reduced with smaller side boosters that stage earlier, & can be re-used.

Are you completly forgetting the economic benefit of building cores that are the same size? And that the side cores are basically F9 cores? The point is to get something that is cost effective.

Falcon Heavy as currently configured has pushed it's payload capacity beyond most anything that is scheduled to be launched, or likely to ever be launched, so what then is going to make it a "success"?   At best, it splits the competition for heavy DoD launches against Delta IV, that alone may make it a commercial success.  The other valid mission is to give extra margin to start re-use testing on stage 2.

No, the extra margin is to allow first stage (and booster) reuse. If the the extra performance allows all three cores to RTLS - and refurbishment is cost effective - than that is a big win for SpaceX.

Stop thinking in the "optimize for performance" mindset. You won't understand SpaceX that way... They are optimizing for cost. One size core, one size upper stage, one size fairing. What else is there to understand?
(And should they start using a Raptor based upper stage, the other benefits will remain, thus reducing booster size would be counter-productive)

I get what you are saying.

Based on the text below, you do not.

Quote
I see it put forward as a near unquestioned "given" everywhere.   I am not disagreeing just to play some devils advocate game.  I think that the benefits of maintaining a common core size work out great IF the flight rate is high for the configuration.    I don't see that possibility until the market completely changes, and that point of elasticity is found that dramatically increases the number of heavy payloads to be launched.  If I am wrong on that, smaller side boosters in comparison to high flight rate F9 core boosters lose.

You seem to get everything completely backwards here.
Common core size is especially good when there are lots of F9's and small amount of FH:s. Keepign Additional production line for small number of FH:s would be very expensive.

Quote
I guess I would really need to know what the incremental cost to the 3.7 meter core production line is to maintain capability for the center core of FH to weigh against a smaller line for side boosters.   An interesting data point might be the cost of an F1 vs. F9 v1.0.   A smaller LRB might cost 1/4 to 1/3 of a F9 side core.   A smaller new booster would be like a F9 side core with 3-4 uses already amortized into it's cost at the outset. 

No, there would be considerable cost INCREASE due the need of second production line for the small boosters.
They might actually end up being MORE expensive.

Quote
The performance loss for a quicker burning small booster, staging earlier, is also not as great as you would think.   So much of the FH side core performance is lost to the expensive energy requirement for RLTS that stages when the rocket is very high, and very far downrange.   It's generally non controversial & accepted that low efficiency is is high cost, and F9 side cores that RTLS are low efficiency from the standpoint of delivering maximum energy to the center core.

Smaller boosters aren't necessarily incompatible with the concept of enabling RTLS re-use for the booster itself, or the center core.   This is especially true for GTO launches that are just out of the reach of RTLS for F9 FT.  Smaller boosters could push a F9 FT past that important threshold for 6-7ton payloads to GTO with RLTS.  (guessing payloads greater than 5.5t, SES-9 will inform us better)  This would smash Ariane 6 & Vulcan in competition for heavier payloads without resorting to a full FH configuration.


You have a payload with certain weight and certain destination trajectory.
You can RTLS either
1) Side cores
2) Side cores + Center core
There is no such situation where you cannot RTLS something with bigger side cores but you can RTLS with smaller side cores.

For the feasibilility of center core recovery, what matters is
1) velocity of staging to stage 2
2) position of staging to stage 2
3) fuel left in center core at this point.

Assuming all the capasity of second stage is used, 1 will practically only depend on the weight and destination of the payload.
Position of staging to stage is more complicated, but in general the higher the average acceleration is, the closer it is. Having bigger boosters with more fuel that burn for longer means higher average acceleration.
And for the amount of fuel left.. The more work is done by the side cores, the more fuel the first stage has left.

For the feasibility of the side booster recovery, what matters, is
1) velocity of side cores at separation
2) position of side cores at separation
3) fuel left in side cores at separation

Bigger side cores will typically fly further away, but as there is much more fuel at separation, they can still fly back better;
To give same impulse to the core stage, the bigger side boosters have to use smaller percentage of their total impulse, leaving more available for the RTLS.


Smaller side boosters would make sense if all the following ones would apply
1) they would not have a production line going for great number of long and cheap 3.7m cores
2) they would then also increase the size of the center core, to get more total fuel and keep the T/W about same
3) they would not try to RTLS the center core.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 01/26/2016 12:09 pm
SpaceX isn't building launch capability for the market as it currently exists... they will have sufficient capability (maybe not on operations side) to launch the world's commercial sats and then some after BocaChica and existing three pads are operational -- assuming reusable technology works as planned.  Same for world's heaviest payloads.

So, they must be planning for a different launch demand.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 01/26/2016 04:59 pm
Stop thinking in the "optimize for performance" mindset. You won't understand SpaceX that way... They are optimizing for cost. One size core, one size upper stage, one size fairing. What else is there to understand?
(And should they start using a Raptor based upper stage, the other benefits will remain, thus reducing booster size would be counter-productive)

I get what you are saying.  I see it put forward as a near unquestioned "given" everywhere.   I am not disagreeing just to play some devils advocate game.  I think that the benefits of maintaining a common core size work out great IF the flight rate is high for the configuration.

No, I'm not sure you are getting it, you have it completely backwards. With a lower flight rate, it is even *worse* to have alternate configurations. The lower your flight rate is, the MORE critical it is to have a common configuration.

I guess I would really need to know what the incremental cost to the 3.7 meter core production line is to maintain capability for the center core of FH to weigh against a smaller line for side boosters.   An interesting data point might be the cost of an F1 vs. F9 v1.0.   A smaller LRB might cost 1/4 to 1/3 of a F9 side core.   A smaller new booster would be like a F9 side core with 3-4 uses already amortized into it's cost at the outset. 

What? I thought you were arguing for a shorter/stubbier F9 core, not an F1 sized core? And that last sentence... I'm having trouble parsing what you mean. SpaceX want reusability. F1 sized boosters won't be reusable without a very different approach. But if you agree that a reused F9 side core could be had for the same price - offering more performance - why in the world would you choose to not use it!?!? Propellant is DIRT CHEAP, only 1-3% of launch costs.

By the way, since you are eager to see Raptor implemented on S2 configurations, you are now violating your espoused principals of simplicity.  I've added some "ones" to your list:   The "one core, one stage 2, one fairing, one engine, one fuel" principal on three counts ( fuel, one S2, multiple engine types) How deep is the commitment to just one of each? 

Who says I'm eager? I think you have misread me. I'm still skeptical of this hypothetical Raptor upper stage - all information so far hinting that direction is from the DoD/USAF. But if that is done, it would have to be a for a very good reason to offset the issue of stage diameter and/or fuel difference.

I respect the philosophy of optimizing for cost, not performance.  I would add that optimizing for profitability is also not incompatible for optimizing cost.

Who said it was?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: ggr on 01/27/2016 12:41 am
I thought I had heard that SpaceX had decided not to bother with crossfeed for FH, in favor of just throttling the center booster. But I can't find anything authoritative that says so. Is this just my flaky memory, or is it official?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 01/27/2016 12:58 am
ggr, I think you are right.  All booster cores would be the same size.  Outer cores would go full thrust, and return to land.  Center core would be throttled down at launch, maybe boost up to full thrust, but probably will not have to.  It would stage higher.  If the payload was on the lite side, it could boost back to launch site.  If it was a heavier payload, it could land on a barge a few hundred miles from launch site.  If the payload was much heavier, the center core might just be expendable without legs.  Lots of choices, but no real change in production. 

My question and concern is with a proposed Raptor upper stage using metholox.  Someone has already figured a 5.2m diameter stage the same length as the existing kerolox upper stage to really improve performance, second stage recovery, or both.  5.2 meter means it would have to be made at a new factory near river or ocean going barge transport, or near the launch pad.   River transportation in America is thousands of miles, the best in the world, so this new wider upper stage can be made almost anywhere. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: matthewkantar on 01/27/2016 01:47 am
As has been pointed out elsewhere, a 5.2 meter second stage can go via air.

https://en.wikipedia.org/wiki/Boeing_Dreamlifter

Matthew
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/27/2016 03:31 am
As has been pointed out elsewhere, a 5.2 meter second stage can go via air.

https://en.wikipedia.org/wiki/Boeing_Dreamlifter

Matthew
More like a Super Guppy, since Dreamlifter is used exclusively for 787 parts and would have a reeeeeallly hard time landing and taking off from the Hawthorne Municipal Airport.

Super Guppy can transport up to 7.62m in diameter, up to 36 meters long (but I think it tapers down).

https://en.wikipedia.org/wiki/Aero_Spacelines_Super_Guppy

Still operated by NASA.

SpaceX is headquartered basically right in the Hawthorne Municipal Airport. On a dry runway with a low fuel load and not too big of a payload, it should be feasible to land and take off from the 1510m runway using a Super Guppy. It'd be annoying to do this often, so that would mean the stage should be reusable and return to launch site or to a barge (not transported often using a Super Guppy).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 01/27/2016 04:58 am
Related to Falcon Heavy testing - The video that was leaked (and subsequently pulled), showed some new closeups of the new test stand. (see pictures below)

The assumption by many (myself included) was that this test stand was built specifically to allow to test all three cores of an FH next to each other, but after looking at the pictures, that does not appear to be how this is built. Unless they plan on rebuilding that mount area significantly.

So perhaps they will simply test each FH core individually, and do some hot fire test together on the pad - and trust their other testing and analysis to verify stress loads. (not without precedent, I don't believe 3 Delta IV cores were tested together until they were at the pad)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: catdlr on 01/27/2016 05:26 am
Related to Falcon Heavy testing - The video that was leaked (and subsequently pulled)


That video can been viewed here:

https://youtu.be/f3ZbLznMiws
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 01/27/2016 05:31 am


No, I'm not sure you are getting it, you have it completely backwards. With a lower flight rate, it is even *worse* to have alternate configurations. The lower your flight rate is, the MORE critical it is to have a common configuration.

I guess I really don't get it.   Following your above logic to it's conclusion, a rocket with a flight rate of zero will absolutely be REQUIRED to have a common configuration.   I was thinking that maybe as that flight rate tends to zero, the rocket builder may want to consider if the market wants a different configuration.   I was thinking that a rocket with a higher flight rate, even if it is possibly more expensive, will make more money that one that doesn't fly.

I guess I would really need to know what the incremental cost to the 3.7 meter core production line is to maintain capability for the center core of FH to weigh against a smaller line for side boosters.   An interesting data point might be the cost of an F1 vs. F9 v1.0.   A smaller LRB might cost 1/4 to 1/3 of a F9 side core.   A smaller new booster would be like a F9 side core with 3-4 uses already amortized into it's cost at the outset. 

What? I thought you were arguing for a shorter/stubbier F9 core, not an F1 sized core? And that last sentence... I'm having trouble parsing what you mean. SpaceX want reusability. F1 sized boosters won't be reusable without a very different approach. But if you agree that a reused F9 side core could be had for the same price - offering more performance - why in the world would you choose to not use it!?!? Propellant is DIRT CHEAP, only 1-3% of launch costs.

Sorry if that was not clear.  I like the performance of a smaller core with 4 M1-D's on 2m core compared to a stubby 3.7m core with 9 M1-D's.   It would have around 1/4 the mass of a F9 side core, and 4/9 the thrust.  As you noted, re-use schemes will be very different.

The point remains that the extra performance of the FH configuration does not seem to have customers lining up.  The primary customer ( DoD) seems to be willing to pay for full expendable.   They may someday choose re-used side cores for missions on FH, or they may not.   Nobody knows how this will play out.  I would add that propellant is only 1-3% of launch cost when weighed against a new vehicle.   Depending on how quickly a booster is depreciated over the first few flights, the cost of fuel starts to become much more significant.  A smaller booster will be cheaper in this metric.

By the way, since you are eager to see Raptor implemented on S2 configurations, you are now violating your espoused principals of simplicity.  I've added some "ones" to your list:   The "one core, one stage 2, one fairing, one engine, one fuel" principal on three counts ( fuel, one S2, multiple engine types) How deep is the commitment to just one of each? 

Who says I'm eager? I think you have misread me. I'm still skeptical of this hypothetical Raptor upper stage - all information so far hinting that direction is from the DoD/USAF. But if that is done, it would have to be a for a very good reason to offset the issue of stage diameter and/or fuel difference.

Well I think we are more alike on this question than anything else.   I took your comments re: Raptor as embracing that development.   I do think a new S2 with a Raptor/Raptor lite + core change is a much more cost significant disruption than making smaller boosters.   SpaceX's motivations for this doesn't follow the "design for cost" mentality you mentioned.   They apparently recognize some efforts are justified because that is what the customer wants, ( DoD, USAF, NASA ) and that it can expire some internal risk on new technology to test it on F9/FH to further their own interests.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jarnis on 01/27/2016 07:17 am
Just a reminder, FH will be the world's largest operational launcher for the next 5-10 years, and the world's lowest price for a kg to orbit.  Ever.  Flaws or no, it won't be easily brushed aside.

It's great to see such positive comments and I really appreciate your enthusiasm, but I would have to note that it may be overly ambitious to have such enthusiasm over a rocket that is yet to fly.

Edited by the PoliteJim2000 app

Nice app, but where can I get the unedited original of the post? :D
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante2121 on 01/27/2016 11:36 am
Apologies if I missed this elsewhere, but has anyone figured out how much an expendable (or reusable) FH with a Raptor upper stage could launch to Mars?

I would be willing to be that this configuration is the first that Spacex will launch to Mars - sooner than they would be able to otherwise if they waited for a full MCT.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: woods170 on 01/27/2016 12:03 pm
Just a reminder, FH will be the world's largest operational launcher for the next 5-10 years, and the world's lowest price for a kg to orbit.  Ever.  Flaws or no, it won't be easily brushed aside.

It's great to see such positive comments and I really appreciate your enthusiasm, but I would have to note that it may be overly ambitious to have such enthusiasm over a rocket that is yet to fly.

Edited by the PoliteJim2000 app

Nice app, but where can I get the unedited original of the post? :D

I suggest you send Jim a PM.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mongo62 on 01/27/2016 12:46 pm
Related to Falcon Heavy testing - The video that was leaked (and subsequently pulled)

That video can been viewed here:

This is a 2-minute video. The original video was about 32 minutes, if I recall correctly. WAY more footage of many more tests than are shown in the 2-minute version.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 01/27/2016 01:06 pm
I would add that propellant is only 1-3% of launch cost when weighed against a new vehicle.   Depending on how quickly a booster is depreciated over the first few flights, the cost of fuel starts to become much more significant.  A smaller booster will be cheaper in this metric.

No, it's not. According to Elon Musk, It's 0.3 % of the cost. 3.3-10 times less than what you say.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 01/27/2016 01:09 pm
What? I thought you were arguing for a shorter/stubbier F9 core, not an F1 sized core? And that last sentence... I'm having trouble parsing what you mean. SpaceX want reusability. F1 sized boosters won't be reusable without a very different approach. But if you agree that a reused F9 side core could be had for the same price - offering more performance - why in the world would you choose to not use it!?!? Propellant is DIRT CHEAP, only 1-3% of launch costs.

Sorry if that was not clear.  I like the performance of a smaller core with 4 M1-D's on 2m core compared to a stubby 3.7m core with 9 M1-D's.   It would have around 1/4 the mass of a F9 side core, and 4/9 the thrust.  As you noted, re-use schemes will be very different.

Reuse scheme is non-existent for the boosters, and harder for the core. You would end up throwing away more hardware.

Quote
The point remains that the extra performance of the FH configuration does not seem to have customers lining up.  The primary customer ( DoD) seems to be willing to pay for full expendable.

DoD is willing to pay high price, but there is nothing in the contracts forbidding spaceX from recovering the cores.
Send the DoD payload to the destination orbit, and return all 3 cores to home. Much better profit than making more expensive smaller rocket and throwing all the cores to ocean.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Herb Schaltegger on 01/27/2016 01:19 pm


More like a Super Guppy, since Dreamlifter is used exclusively for 787 parts and would have a reeeeeallly hard time landing and taking off from the Hawthorne Municipal Airport.

One of my best friends is a Dreamlifter pilot. I can confirm that all the cargo he flies right now are 787 wing and fuselage components. I will ask him if anyone has contacted his organization about other outsize payloads and see if he can give me any performance data regarding payload weight versus field length at standard conditions.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 01/27/2016 01:47 pm
The assumption by many (myself included) was that this test stand was built specifically to allow to test all three cores of an FH next to each other, but after looking at the pictures, that does not appear to be how this is built. Unless they plan on rebuilding that mount area significantly.

So perhaps they will simply test each FH core individually, and do some hot fire test together on the pad - and trust their other testing and analysis to verify stress loads. (not without precedent, I don't believe 3 Delta IV cores were tested together until they were at the pad)
So, they built the new below-ground test stand solely for the purpose of reducing noise?  And I guess you don't need a crane to lift it up onto the above-ground test stand.  But that seems like a lot of expense for minimal gain.  Maybe there's a limit to the amount of noise complaints the locals are willing to tolerate.

Not contesting your analysis, just seems odd is all.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 01/27/2016 03:16 pm
Well, presumably the new test stand also has the supercooling GSE, and this move frees up the tripod for (say) Raptor work.  Building a new test stand probably also prevented a long disruption in the v1.1 test cycle while they were working on the v1.2 GSE, I guess?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: starsilk on 01/27/2016 04:20 pm
As has been pointed out elsewhere, a 5.2 meter second stage can go via air.

https://en.wikipedia.org/wiki/Boeing_Dreamlifter

Matthew
More like a Super Guppy, since Dreamlifter is used exclusively for 787 parts and would have a reeeeeallly hard time landing and taking off from the Hawthorne Municipal Airport.

Super Guppy can transport up to 7.62m in diameter, up to 36 meters long (but I think it tapers down).

https://en.wikipedia.org/wiki/Aero_Spacelines_Super_Guppy

Still operated by NASA.

SpaceX is headquartered basically right in the Hawthorne Municipal Airport. On a dry runway with a low fuel load and not too big of a payload, it should be feasible to land and take off from the 1510m runway using a Super Guppy. It'd be annoying to do this often, so that would mean the stage should be reusable and return to launch site or to a barge (not transported often using a Super Guppy).

McGregor is the problem, by barge or air.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Nomadd on 01/27/2016 04:25 pm


More like a Super Guppy, since Dreamlifter is used exclusively for 787 parts and would have a reeeeeallly hard time landing and taking off from the Hawthorne Municipal Airport.

One of my best friends is a Dreamlifter pilot. I can confirm that all the cargo he flies right now are 787 wing and fuselage components. I will ask him if anyone has contacted his organization about other outsize payloads and see if he can give me any performance data regarding payload weight versus field length at standard conditions.
Dreamlifter can only hold a 104 foot 787-9 center section. A 787-10 section at something like 120 feet won't fit and they have to make that plane in Charleston, where the center sections are assembled. I'm not sure if the smaller diameter F9 1st stage might mean a longer one of those would go in. 787 fuselages are about 5.9m.
 A modified 747-8F might handle a 1st stage without needing the Dreamlifter fuselage, and just the swinging tail, but it would be at least a $400 million investment.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 01/27/2016 05:13 pm
No, I'm not sure you are getting it, you have it completely backwards. With a lower flight rate, it is even *worse* to have alternate configurations. The lower your flight rate is, the MORE critical it is to have a common configuration.

I guess I really don't get it.   Following your above logic to it's conclusion, a rocket with a flight rate of zero will absolutely be REQUIRED to have a common configuration.   I was thinking that maybe as that flight rate tends to zero, the rocket builder may want to consider if the market wants a different configuration.

Obviously a rocket with a flight rate of one (or zero) will have a common configuration. As should your 2nd, 3rd, 4th, and so on. Or do you think it is cost effective to design and build a completely custom rocket for every payload? Flight rate is *essential*. And you can't afford to dick around with custom configurations until you have a certain flight rate. THEN you can introduce variations. Presuming that you want to be cost effective. (historically this has not been a concern for most space programs)

I was thinking that a rocket with a higher flight rate, even if it is possibly more expensive, will make more money that one that doesn't fly.

Obviously. But you seem to to be approaching the whole idea backwards, but getting a high flight rate by initially custom building rockets, and THEN when you have a higher flight rate you standardize.  ::) This makes no economical sense at all, but that hasn't stopped some space agencies from trying it. Which is a major reason why space flight is so expensive. You have the right goal in mind (flight rate), but you are trying to get there the wrong way.

Sorry if that was not clear.  I like the performance of a smaller core with 4 M1-D's on 2m core compared to a stubby 3.7m core with 9 M1-D's.   It would have around 1/4 the mass of a F9 side core, and 4/9 the thrust.  As you noted, re-use schemes will be very different.

So you want to introduce a whole new production line for a 2m rocket, to produce a booster powered by 4 M1D's, which I can't see how it would be reusable - How in the world will this save costs compared to a reused standard core?

The point remains that the extra performance of the FH configuration does not seem to have customers lining up.  The primary customer ( DoD) seems to be willing to pay for full expendable.

Enough customers are lining up. They have several commercial orders for FH. And they do want to offer the DoD the full capability range. And the extra performance over Delta IV-Heavy will allow for reusability of 1st stage and booster cores.

But there is something about FH that you seem to forget... It doesn't have to be cost effective on its own.  It is made up from F9 parts! If more customers want to use F9, that's fine. If more want to use FH, that's fine.  But it all comes out of the same production line.

Depending on how quickly a booster is depreciated over the first few flights, the cost of fuel starts to become much more significant.  A smaller booster will be cheaper in this metric.

NOT if you throw it away every time. You have yet to propose how your 2m diameter 4 M1D booster will be reused.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 01/27/2016 05:17 pm
Related to Falcon Heavy testing - The video that was leaked (and subsequently pulled)

That video can been viewed here:

This is a 2-minute video. The original video was about 32 minutes, if I recall correctly. WAY more footage of many more tests than are shown in the 2-minute version.

Nope, you are thinking of the wrong video.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 01/27/2016 05:35 pm
Well, presumably the new test stand also has the supercooling GSE, and this move frees up the tripod for (say) Raptor work.  Building a new test stand probably also prevented a long disruption in the v1.1 test cycle while they were working on the v1.2 GSE, I guess?

The tri-core tests would not have fit on the tripod and would have been much louder than the single core, so in-ground test stand solves both issues.  Testing single cores there frees the tripod for (quieter) second stage tests, no matter the fuel -- with reuse, second stages might become the bottleneck to launch cadence.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 01/27/2016 05:38 pm
The tri-core tests would not have fit on the tripod
The point we are discussing is that it appears that they won't fit on the in-ground test stand either.

Agreed that it makes sense that the above-ground test stand will be doing a lot of S2 testing.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 01/27/2016 05:45 pm
The tri-core tests would not have fit on the tripod
The point we are discussing is that it appears that they won't fit on the in-ground test stand either.

Agreed that it makes sense that the above-ground test stand will be doing a lot of S2 testing.

Sorry, missed that.
Cannot imagine they would build such a test facility without FH capability, though.
In fact, a past tour (won't even attempt to find the reference) described the new in-ground stand as for the FH "at least for now..." which implies FH and more can/will be tested there.
The base plate (launch mount?) probably has two versions.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 01/27/2016 05:54 pm
The tri-core tests would not have fit on the tripod
The point we are discussing is that it appears that they won't fit on the in-ground test stand either.

Agreed that it makes sense that the above-ground test stand will be doing a lot of S2 testing.

Stage 2 tests aren't done on the tripod, as far as I know. They have a smaller more convenient test stand for that, located by the individual M1D test stands. (see image)

But I could be wrong.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hallmh on 01/27/2016 06:00 pm

A modified 747-8F might handle a 1st stage without needing the Dreamlifter fuselage, and just the swinging tail, but it would be at least a $400 million investment.

When cores are transported by road, I believe they just put wheels on the back and a cab at the front, using the rocket structure itself to hold everything together.

I wonder if they could do something similar for air transfers - get Mr Rutan to design a front end with wings and a cockpit, tack on a tailplane at the other end and fly. There's even generous fuel tanks ready built in!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mongo62 on 01/27/2016 06:10 pm
Related to Falcon Heavy testing - The video that was leaked (and subsequently pulled)

That video can been viewed here:

This is a 2-minute video. The original video was about 32 minutes, if I recall correctly. WAY more footage of many more tests than are shown in the 2-minute version.

Nope, you are thinking of the wrong video.

This is the video I was thinking of: 32 minutes of (mostly) test footage:

https://www.youtube.com/watch?v=Kdh7MKELv2g

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 01/27/2016 06:36 pm
Yes, but that was NOT the video we were discussing.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 01/27/2016 08:40 pm
A question.  IF, they do go to a 5.2m upper Raptor stage.  Would it still be made at Hawthorn?  Or would they make the upper stage and Raptor engines at another location, like near water transportation?  Seems it would be cheaper than air transportation. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 01/28/2016 04:15 am
What? I thought you were arguing for a shorter/stubbier F9 core, not an F1 sized core? And that last sentence... I'm having trouble parsing what you mean. SpaceX want reusability. F1 sized boosters won't be reusable without a very different approach. But if you agree that a reused F9 side core could be had for the same price - offering more performance - why in the world would you choose to not use it!?!? Propellant is DIRT CHEAP, only 1-3% of launch costs.

Sorry if that was not clear.  I like the performance of a smaller core with 4 M1-D's on 2m core compared to a stubby 3.7m core with 9 M1-D's.   It would have around 1/4 the mass of a F9 side core, and 4/9 the thrust.  As you noted, re-use schemes will be very different.

Reuse scheme is non-existent for the boosters, and harder for the core. You would end up throwing away more hardware.

1.  Your previous post on fuel being .3% vs. 3% of vehicle cost is correct per quotes from E. Musk.  I went with what Lars posted earlier.  What impact or change does this have on any of the arguments?   

2. You say "Reuse scheme is non-existent for the boosters, and harder for the core. You would end up throwing away more hardware."    
You have absolutely no way of knowing the reuse capability of either case, booster or core, unless you define mass of the payload.     Why do you think returning a small booster that separates lower and slower than the F9 side cores is a.) impossible, b.) harder than RTLS or DPL?  Illogical.   
As far as returning the core, again, what is the mass of the payload?  In the case of both RTLS and DPL returns, in comparison to FH configuration,  the core with smaller boosters will be closer to the launch site, lower in altitude, and similar velocity when it is ready to stage ( because the "boost" is imparted earlier in the flight)  This condition favors RTLS and is probably neutral for DPL.

It is completely premature to say more hardware will be thrown away. 

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/28/2016 04:26 am
What? I thought you were arguing for a shorter/stubbier F9 core, not an F1 sized core? And that last sentence... I'm having trouble parsing what you mean. SpaceX want reusability. F1 sized boosters won't be reusable without a very different approach. But if you agree that a reused F9 side core could be had for the same price - offering more performance - why in the world would you choose to not use it!?!? Propellant is DIRT CHEAP, only 1-3% of launch costs.

Sorry if that was not clear.  I like the performance of a smaller core with 4 M1-D's on 2m core compared to a stubby 3.7m core with 9 M1-D's.   It would have around 1/4 the mass of a F9 side core, and 4/9 the thrust.  As you noted, re-use schemes will be very different.

Reuse scheme is non-existent for the boosters, and harder for the core. You would end up throwing away more hardware.

1.  Your previous post on fuel being .3% vs. 3% of vehicle cost is correct per quotes from E. Musk.  I went with what Lars posted earlier.  What impact or change does this have on any of the arguments?   

2. You say "Reuse scheme is non-existent for the boosters, and harder for the core. You would end up throwing away more hardware."    
You have absolutely no way of knowing the reuse capability of either case, booster or core, unless you define mass of the payload.     Why do you think returning a small booster that separates lower and slower than the F9 side cores is a.) impossible, b.) harder than RTLS or DPL?  Illogical.   
As far as returning the core, again, what is the mass of the payload?  In the case of both RTLS and DPL returns, in comparison to FH configuration,  the core with smaller boosters will be closer to the launch site, lower in altitude, and similar velocity when it is ready to stage ( because the "boost" is imparted earlier in the flight)  This condition favors RTLS and is probably neutral for DPL.

It is completely premature to say more hardware will be thrown away.
Actually the only real disadvantage of the smaller boosters is that the landing hardware consumes a higher percentage of the dry weight. Also the smaller diameter tanks are also heavier for the volume they hold so a significant lower PF. In a reusable system this jsut means that the manufacturing costs are just slightly higher on a kg of payload basis than for larger payloads with the larger boosters. Almost such that there is little price difference between the small booster FH price and a large booster FH price.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 01/28/2016 05:25 am
No, I'm not sure you are getting it, you have it completely backwards. With a lower flight rate, it is even *worse* to have alternate configurations. The lower your flight rate is, the MORE critical it is to have a common configuration.

I guess I really don't get it.   Following your above logic to it's conclusion, a rocket with a flight rate of zero will absolutely be REQUIRED to have a common configuration.   I was thinking that maybe as that flight rate tends to zero, the rocket builder may want to consider if the market wants a different configuration.

Obviously a rocket with a flight rate of one (or zero) will have a common configuration. As should your 2nd, 3rd, 4th, and so on. Or do you think it is cost effective to design and build a completely custom rocket for every payload? Flight rate is *essential*. And you can't afford to dick around with custom configurations until you have a certain flight rate. THEN you can introduce variations. Presuming that you want to be cost effective. (historically this has not been a concern for most space programs)

I was thinking that a rocket with a higher flight rate, even if it is possibly more expensive, will make more money that one that doesn't fly.

Obviously. But you seem to to be approaching the whole idea backwards, but getting a high flight rate by initially custom building rockets, and THEN when you have a higher flight rate you standardize.  ::) This makes no economical sense at all, but that hasn't stopped some space agencies from trying it. Which is a major reason why space flight is so expensive. You have the right goal in mind (flight rate), but you are trying to get there the wrong way.


This exchange is passing the TL;DR threshold, so I cut it down and want to clarify my proposal, as well as ask you something.

1.  I am proposing 2 vehicle configurations, not multiple ( more than 2) custom configurations for every payload.  They require a core, and 2 smaller boosters.   In my scenario, the "Core" would be the vehicle with the high flight rate, as I would use a standardized core that could attach the small boosters, this configuration becomes the "Heavy".  I would use the same core to serve the role of the single stick F9 FT. 

2.  You affirm that flight rate is essential, yet FH has a very very low ( zero, currently) flight rate.   Is FH immune from this paradigm because it comes off the same assembly line?  I may partially agree with this conflicting assessment, I'm not trying to set some logic trap to blather about, I'm just interested in how you see the "essential" qualifier of high flight rate doesn't apply to FH?  What about operations?  Ground support equipment, integration, staffing, training, pad proficiency etc.

3.  Even though I have not proposed custom configurations, your point about me getting the "whole idea backwards, but getting a high flight rate by initially custom building rockets, and THEN when you have a higher flight rate you standardize.   This makes no economical sense at all..."  raised some thoughts for me.  In light of that backwards thinking scheme, how do you assess the evolution of the SpaceX paper F5 rocket to the F9 v1.0, to V1.1, and now F9 FT?  Was it backwards?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 01/28/2016 05:31 am
What? I thought you were arguing for a shorter/stubbier F9 core, not an F1 sized core? And that last sentence... I'm having trouble parsing what you mean. SpaceX want reusability. F1 sized boosters won't be reusable without a very different approach. But if you agree that a reused F9 side core could be had for the same price - offering more performance - why in the world would you choose to not use it!?!? Propellant is DIRT CHEAP, only 1-3% of launch costs.

Sorry if that was not clear.  I like the performance of a smaller core with 4 M1-D's on 2m core compared to a stubby 3.7m core with 9 M1-D's.   It would have around 1/4 the mass of a F9 side core, and 4/9 the thrust.  As you noted, re-use schemes will be very different.

Reuse scheme is non-existent for the boosters, and harder for the core. You would end up throwing away more hardware.

1.  Your previous post on fuel being .3% vs. 3% of vehicle cost is correct per quotes from E. Musk.  I went with what Lars posted earlier.  What impact or change does this have on any of the arguments?   

2. You say "Reuse scheme is non-existent for the boosters, and harder for the core. You would end up throwing away more hardware."    
You have absolutely no way of knowing the reuse capability of either case, booster or core, unless you define mass of the payload.     Why do you think returning a small booster that separates lower and slower than the F9 side cores is a.) impossible, b.) harder than RTLS or DPL?  Illogical.   

Because 4-engine boosters cannot land like a 9-engine booster lands. There is no center engine, and the T/W ratio is way too high.

Quote

As far as returning the core, again, what is the mass of the payload?  In the case of both RTLS and DPL returns, in comparison to FH configuration,  the core with smaller boosters will be closer to the launch site, lower in altitude, and similar velocity when it is ready to stage ( because the "boost" is imparted earlier in the flight)  This condition favors RTLS and is probably neutral for DPL.

Wrong.

1) For the acceleration, what matters is the total T/W ratio of the vehicle, not the T/W of the booster.

Simple example: Rocket A has 250 tonne first stage and 50 tonne second stage. First stage has thrust of 400 tonnes, second stage 40 tonnes. The T/W at liftoff is 1.333.

Now lets make a rocket with smaller first stage. First stage mass is dropped to 150 tonnes while engine thrust is dropped to 250 tonnes.

First stage T/W has increased from 1.6 to 1.666, but the actual T/W of the whole vehicle has decreased from 1.333 to 1.25.

2) Separating the boosters earlier means there is lower acceleration between boosters separation and staging to stage2, leading the core to fly further away before staging to stage 2

3) Less reserve capasity mean the trajectory cannot be some optimized for easy flyback of boosters.
Trajectory optimized for booster recovery is much higher than "ordinary trajectory" trajectory, first stage burning much more to fight gravity and jump to high altitude, and second stage burning more horizontally while losing vertical velocity.

But if the rocket is on the edge of it's capasity, it has to use a "payload-optimized" lower trajectory where the earlier stages fly further.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 01/28/2016 06:48 am
2.  You affirm that flight rate is essential, yet FH has a very very low ( zero, currently) flight rate.   Is FH immune from this paradigm because it comes off the same assembly line?  I may partially agree with this conflicting assessment, I'm not trying to set some logic trap to blather about, I'm just interested in how you see the "essential" qualifier of high flight rate doesn't apply to FH?  What about operations?  Ground support equipment, integration, staffing, training, pad proficiency etc.

Yes. FH is *mostly* immune to concerns about flight rate, since it basically uses F9 components. Once the launch pads support FH (an extra investment for sure), the actual distribution of flight rate between F9 and FH does not matter much.  Your other concerns (Ground support equipment, integration, staffing, training, pad proficiency) will be a small factor, but are still less than what they would be with your model of multiple size cores.

3.  Even though I have not proposed custom configurations, your point about me getting the "whole idea backwards, but getting a high flight rate by initially custom building rockets, and THEN when you have a higher flight rate you standardize.   This makes no economical sense at all..."  raised some thoughts for me.  In light of that backwards thinking scheme, how do you assess the evolution of the SpaceX paper F5 rocket to the F9 v1.0, to V1.1, and now F9 FT?  Was it backwards?

They had to start somewhere, work with what you have at hand. They had limited funds. F5 was offered to customers, there was not sufficient interest. With F9 they were able to bid for COTS/CRS. The v1.1 and FT are/were simply opportunities to redo and refine the launcher with lessons learned. F9 v1.0 was not powerful enough to tap into the GTO market.

This evolution does not contradict my "scheme" at all. At every point SpaceX has attempted to have only one model in use, switching over production and pads all at once. This is in contrast to what you seem to advocate - that they should have operated multiple versions at the same time to fit customer demand. F4 (your small booster), F5, F9v1.0, and F9 FT. (unless I misunderstand)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 01/28/2016 07:06 am


Actually the only real disadvantage of the smaller boosters is that the landing hardware consumes a higher percentage of the dry weight. Also the smaller diameter tanks are also heavier for the volume they hold so a significant lower PF. In a reusable system this just means that the manufacturing costs are just slightly higher on a kg of payload basis than for larger payloads with the larger boosters. Almost such that there is little price difference between the small booster FH price and a large booster FH price.

I was with you on the small vs. large tradeoffs until the last sentence.   If the per kg mfg. cost are just slightly higher for the small vs. large booster, how would a small booster 1/4th the mass of a larger booster cost the same?

My thinking for a small F1 class booster wast that it would cost around $10M.   The F1 in 2015 dollars is suggested by Wiki to be around $7M, so adding 3 more M1-D's for a 4 engine booster comes in around $10M.   A F9 core stage is estimated to cost $40M, so this follows the per kg rule you said, but the smaller booster is much cheaper.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 01/28/2016 07:25 am

Because 4-engine boosters cannot land like a 9-engine booster lands. There is no center engine, and the T/W ratio is way too high.

Quote

As far as returning the core, again, what is the mass of the payload?  In the case of both RTLS and DPL returns, in comparison to FH configuration,  the core with smaller boosters will be closer to the launch site, lower in altitude, and similar velocity when it is ready to stage ( because the "boost" is imparted earlier in the flight)  This condition favors RTLS and is probably neutral for DPL.

Wrong.

1) For the acceleration, what matters is the total T/W ratio of the vehicle, not the T/W of the booster.

Simple example: Rocket A has 250 tonne first stage and 50 tonne second stage. First stage has thrust of 400 tonnes, second stage 40 tonnes. The T/W at liftoff is 1.333.

Now lets make a rocket with smaller first stage. First stage mass is dropped to 150 tonnes while engine thrust is dropped to 250 tonnes.

First stage T/W has increased from 1.6 to 1.666, but the actual T/W of the whole vehicle has decreased from 1.333 to 1.25.

Is center core propulsive landing the only possible method?   That is a pretty bold statement.

You chose an example that is opposite of what is being discussed.   Try these numbers which match closely to a FH and a FH/Small Booster configuration as I proposed.

SpaceX Standard FH configuration
FH center core mass: 600t
FH side core mass: 415t
Thrust of all 3 cores: 2082t ( 694t each booster)
T/W =1.45

Proposed small booster configuration:
Same FH center core: 600t
Small side core booster: 110t each
Small booster thrust: 308t ( 4 M1-D's each)
T/W = 1.60

Does this affect your assessment of staging impact on RLTS or DPL?



Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 01/28/2016 07:32 am

....This is in contrast to what you seem to advocate - that they should have operated multiple versions at the same time to fit customer demand. F4 (your small booster), F5, F9v1.0, and F9 FT. (unless I misunderstand)

I do not advocate that at all.  I do advocate operating a single F9 FT configuration that can also that same configuration as the center core of FH "lite" with smaller boosters.  The boosters would only be used as boosters, not as some F4 configuration with it's own S2, PLF, etc.

I agree with your assessment of SpaceX.   They did what they had to do to get the next contract, and get entrance into markets to make a viable business.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 01/28/2016 07:50 am

Because 4-engine boosters cannot land like a 9-engine booster lands. There is no center engine, and the T/W ratio is way too high.

Quote

As far as returning the core, again, what is the mass of the payload?  In the case of both RTLS and DPL returns, in comparison to FH configuration,  the core with smaller boosters will be closer to the launch site, lower in altitude, and similar velocity when it is ready to stage ( because the "boost" is imparted earlier in the flight)  This condition favors RTLS and is probably neutral for DPL.

Wrong.

1) For the acceleration, what matters is the total T/W ratio of the vehicle, not the T/W of the booster.

Simple example: Rocket A has 250 tonne first stage and 50 tonne second stage. First stage has thrust of 400 tonnes, second stage 40 tonnes. The T/W at liftoff is 1.333.

Now lets make a rocket with smaller first stage. First stage mass is dropped to 150 tonnes while engine thrust is dropped to 250 tonnes.

First stage T/W has increased from 1.6 to 1.666, but the actual T/W of the whole vehicle has decreased from 1.333 to 1.25.

Is center core propulsive landing the only possible method?   That is a pretty bold statement.

No, it's not the only method. But it's the only method DONE SO FAR. AND proposing ANOTHER yet-unknown method for very small amount of launches.. It just makes absolutely NO economicall sense(for both development and for operations), when the only benefit is about saving on fuel costs for about 0.15% of the launch price


Quote
You chose an example that is opposite of what is being discussed.   Try these numbers which match closely to a FH and a FH/Small Booster configuration as I proposed.

SpaceX Standard FH configuration
FH center core mass: 600t
FH side core mass: 415t
Thrust of all 3 cores: 2082t ( 694t each booster)
T/W =1.45

Proposed small booster configuration:
Same FH center core: 600t
Small side core booster: 110t each
Small booster thrust: 308t ( 4 M1-D's each)
T/W = 1.60

Does this affect your assessment of staging impact on RLTS or DPL?

No:
1) fill the tanks of the normal side boosters only partially and you get the initial T/W of exactly same as your proposal, can burn the boosters longer having higher T/W later in the flight, can do the the RTLS and landing like F9 does. And no need to keep two separate production lines.

There is absolutely NOTHING that your proposed configuration can do that ordinary FH cannot do for cheaper.

2) See my points 2 and 3 in my previous post.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 01/28/2016 07:56 am
My thinking for a small F1 class booster wast that it would cost around $10M.   The F1 in 2015 dollars is suggested by Wiki to be around $7M, so adding 3 more M1-D's for a 4 engine booster comes in around $10M.   A F9 core stage is estimated to cost $40M, so this follows the per kg rule you said, but the smaller booster is much cheaper.

You do not think about the cost and complexity of having a separate production line for those quite rarely used different-sized cores.

3.7m Falcon 9 cores are mass-produced at production line which exists. There exists no production line for 2-meter cores, and building and maintaining such production line is expensive.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Rebel44 on 01/28/2016 08:42 am
Is there any new info about date of 1st FH launch?

thx
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dror on 01/28/2016 05:59 pm

You do not think about the cost and complexity of having a separate production line for those quite rarely used different-sized cores.

3.7m Falcon 9 cores are mass-produced at production line which exists. There exists no production line for 2-meter cores, and building and maintaining such production line is expensive.

So will that scheme work with a F5 side boosters (which can be manufactured in the same line as F9)?

IMO,
When they gonna use side boosters it will either be F9FT or F5FT or maybe F1Raptor (if such creatures become viable).
2 meter F4 beasts...  :-\ I dont think we'll see those.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 01/28/2016 07:37 pm

You chose an example that is opposite of what is being discussed.   Try these numbers which match closely to a FH and a FH/Small Booster configuration as I proposed.

SpaceX Standard FH configuration
FH center core mass: 600t
FH side core mass: 415t
Thrust of all 3 cores: 2082t ( 694t each booster)
T/W =1.45

Proposed small booster configuration:
Same FH center core: 600t
Small side core booster: 110t each
Small booster thrust: 308t ( 4 M1-D's each)
T/W = 1.60

Does this affect your assessment of staging impact on RLTS or DPL?

No:
1) fill the tanks of the normal side boosters only partially and you get the initial T/W of exactly same as your proposal, can burn the boosters longer having higher T/W later in the flight, can do the the RTLS and landing like F9 does. And no need to keep two separate production lines.

There is absolutely NOTHING that your proposed configuration can do that ordinary FH cannot do for cheaper.

Maybe we have a language barrier, I don't know, it could be something else.  But are you suggesting that by only partially filling the FH side core tanks, you will match the T/W ratio of my proposed smaller boosters, AND then burn the regular FH side boosters longer with higher T/W later in the flight?   Is that before or after they run out of gas?

I guess if partially filling the FH sidecore tanks is such a great idea to get initial improvement in T/W, maybe you can just put in just enough to clear the TEL with even better T/W, and then throttle down, or even shut off some engines until later in the burn...before you run out of gas.

/s off

As far as the statements about cost, and smaller booster not being able to do what a ordinary FH can do cheaper, you, me, nor anyone else "KNOWS" this.   It cannot be known until the flight rate of the smaller boosters is used to determine a per booster cost.  It is all speculative. 

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: whitelancer64 on 01/28/2016 07:47 pm
Is there any new info about date of 1st FH launch?

thx

It is still slated for April 2016.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 01/28/2016 08:32 pm

You do not think about the cost and complexity of having a separate production line for those quite rarely used different-sized cores.

3.7m Falcon 9 cores are mass-produced at production line which exists. There exists no production line for 2-meter cores, and building and maintaining such production line is expensive.

I thought a lot about the complexity.  My entire point is driven by the revenue considerations, not the "production lines are expensive" fact you keep repeating.   You know what else is expensive?  Losing launch contracts to put +6t sattellites into GTO.  It is a fact FH has a very low demand.  The contracts thrown SpaceX's way from Immarsat are more than likely to be for wringing price concessions from Ariane as they are a vote of confidence in FH.   Capturing that business will generate a sufficient flight rate to justify a different core size, if needed.   My choice of 2m is not set in stone, or ideological.   It was picked to suit other constraints.   If I said, hey, lets build a 10 meter tall by 3.7m core booster with 4 engines, would you be more inclined to like it?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 01/28/2016 08:55 pm

You chose an example that is opposite of what is being discussed.   Try these numbers which match closely to a FH and a FH/Small Booster configuration as I proposed.

SpaceX Standard FH configuration
FH center core mass: 600t
FH side core mass: 415t
Thrust of all 3 cores: 2082t ( 694t each booster)
T/W =1.45

Proposed small booster configuration:
Same FH center core: 600t
Small side core booster: 110t each
Small booster thrust: 308t ( 4 M1-D's each)
T/W = 1.60

Does this affect your assessment of staging impact on RLTS or DPL?

No:
1) fill the tanks of the normal side boosters only partially and you get the initial T/W of exactly same as your proposal, can burn the boosters longer having higher T/W later in the flight, can do the the RTLS and landing like F9 does. And no need to keep two separate production lines.

There is absolutely NOTHING that your proposed configuration can do that ordinary FH cannot do for cheaper.

Maybe we have a language barrier, I don't know, it could be something else.  But are you suggesting that by only partially filling the FH side core tanks, you will match the T/W ratio of my proposed smaller boosters, AND then burn the regular FH side boosters longer with higher T/W later in the flight?   Is that before or after they run out of gas?

I guess if partially filling the FH sidecore tanks is such a great idea to get initial improvement in T/W, maybe you can just put in just enough to clear the TEL with even better T/W, and then throttle down, or even shut off some engines until later in the burn...before you run out of gas.

YOU are the who was hyping the high T/W to help make recovery easier. I'm just showing that the ordinary FH is better EVEN ON THIS REGARD, winning on YOUR OWN FRONT.

And here are numbers for it:

Leave 65 tonnes fuel out of both side cores. Now they weight 350 tonnes. Initial T/W is the same as your 1.6.

Both side cores will have about 3 times more fuel than your proposal has, but consume only 2.25 times more fuel. So the boosters will burn for 33% longer.

This 33% longer burn time of boosters both
1) gives much higher average acceleration, meaning center core does not fly so far
2) gives much higher total impulse, allows using higher (unoptimal for capasity to orbit, optimal to recovery) trajectory, meaning more of the speed is vertical, less horizontal, easier to fly back.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 01/28/2016 08:56 pm
You know what else is expensive?  Losing launch contracts to put +6t sattellites into GTO.  It is a fact FH has a very low demand.  The contracts thrown SpaceX's way from Immarsat are more than likely to be for wringing price concessions from Ariane as they are a vote of confidence in FH.   Capturing that business will generate a sufficient flight rate to justify a different core size, if needed.   My choice of 2m is not set in stone, or ideological.   It was picked to suit other constraints.   If I said, hey, lets build a 10 meter tall by 3.7m core booster with 4 engines, would you be more inclined to like it?

But the incremental cost to make an FHFT over an F9 for a low number of launches is going to be much cheaper than creating a new 2 meter booster core.

The real questions will be where the cut offs are for payload performance between F9E, F9RASDS, F9RTLS, FH variants to see whether anything else is even needed.  If F9RASDS gets us to 5t, then FH3R (centre core to ASDS) takes over smoothly from there the added $20M going from 5t to 6t is not that big a jump (presuming $40M to $60M roughly). I am guessing F9RTLS might be $5M cheaper than F9RASDS with $1M or so going to the different ops costs AND $4M being the added risk of loosing the booster over RTLS.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 01/28/2016 09:10 pm

You do not think about the cost and complexity of having a separate production line for those quite rarely used different-sized cores.

3.7m Falcon 9 cores are mass-produced at production line which exists. There exists no production line for 2-meter cores, and building and maintaining such production line is expensive.

I thought a lot about the complexity.  My entire point is driven by the revenue considerations, not the "production lines are expensive" fact you keep repeating.   You know what else is expensive?  Losing launch contracts to put +6t sattellites into GTO.  It is a fact FH has a very low demand.

What mushrooms have you been eating?

Your revenue considerations are totally bogus and wrongly calculated, as I and others have pointed out several times. Proposing a rocket which needs extra development and extra tooling and another production line and arrives much later does not actually make these better. YOUR PROPOSAL is the one that would end up loosing launch contracts.

1) Partially reusable FH is the cheapest rocket for those +6t GTO payloads. None of these contracts is lost because FH is "too big".

What matters is the cost, not size. FH is cheap even though it's big. And because it's big, it can launch at least 6.4t GTO payloads while recovering all cores, and something like 15t GTO while recovering the outer cores.

2) For your proposal Some DoD launch contracts would simple be lost because your proposal does not have the capasity. DoD has payloads which required upgrading the Delta IVH to RS-68A. Your proposal has less capasity than the upgraded Delta IVH, you could not even launch these to desider orbit. FH might allow launching these to the destination orbit while still recovering the boosters(but propably not center core).

Quote
My choice of 2m is not set in stone, or ideological.   It was picked to suit other constraints.   If I said, hey, lets build a 10 meter tall by 3.7m core booster with 4 engines, would you be more inclined to like it?

Something like 10 meter tall 3.7 meter core booster might make _some_ sense, because they could be built with same tooling than F9 cores are built, and they would actually be cheaper to manufacture. But they still could not be recovered like the 9-engine cores are recovered.
If they would not get the recovery and reuse of the boosters working, then it would start making very much sense.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 01/28/2016 09:12 pm
This thread is about Falcon Heavy.  Falcon Heavy is well established as three F9FT cores, not some other configuration.  Can we keep the theoretical discussion of imaginary variants somewhere else please?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hopalong on 01/28/2016 09:30 pm
Is there any new info about date of 1st FH launch?

thx

It is still slated for April 2016.

Any information on what the payload will be for the first flight?

I would love to see them send a Dragon on a free return around the moon (with wheel of cheese), but I suspect it will just be a mass simulator.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Zed_Noir on 01/29/2016 06:22 am
Is there any new info about date of 1st FH launch?

thx

It is still slated for April 2016.

Any information on what the payload will be for the first flight?

I would love to see them send a Dragon on a free return around the moon (with wheel of cheese), but I suspect it will just be a mass simulator.

Think whatever payload they send up in the first Falcon Heavy will be inside a fairing. Since most early Falcon Heavy flights will be GEO sats. They have to make sure that the fairing works on the Falcon Heavy before carrying up a paying customer.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jarnis on 01/29/2016 06:59 am
Is there any new info about date of 1st FH launch?

thx

It is still slated for April 2016.

Since we haven't heard of a word yet that Heavy hardware would be in testing at Texas and this being first flight of new type, off a new pad... call me a pessimist, but April ain't going to happen.

This year. Maybe sometime in the Summer?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hopalong on 01/29/2016 09:30 am
Is there any new info about date of 1st FH launch?

thx

It is still slated for April 2016.

Any information on what the payload will be for the first flight?

I would love to see them send a Dragon on a free return around the moon (with wheel of cheese), but I suspect it will just be a mass simulator.

Think whatever payload they send up in the first Falcon Heavy will be inside a fairing. Since most early Falcon Heavy flights will be GEO sats. They have to make sure that the fairing works on the Falcon Heavy before carrying up a paying customer.

Yes, I believe you to be correct, GEO will be the main workload for the FH, so the GTO missions will be tested first, the TLI and TMI missions will come later. I would not be surprised if the 2nd stage is given a good workout, that is multiple starts, long coasts between starts while not carrying a customer payload.
I think the S2 has done 3 starts up to now?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Herb Schaltegger on 01/29/2016 12:57 pm

Is there any new info about date of 1st FH launch?

thx

It is still slated for April 2016.

Any information on what the payload will be for the first flight?

I would love to see them send a Dragon on a free return around the moon (with wheel of cheese), but I suspect it will just be a mass simulator.

Think whatever payload they send up in the first Falcon Heavy will be inside a fairing. Since most early Falcon Heavy flights will be GEO sats. They have to make sure that the fairing works on the Falcon Heavy before carrying up a paying customer.

Well, the boosters will (almost certainly) stage well before the fairing. Jettisoning the fairing should be no more risky or challenging than doing so on any F9 to date, I would think.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 01/29/2016 02:15 pm
Good point. The tri-core configuration would seem to be the testing hurdle, not second stage/fairing.
USAF has already examined the internal processes at SpaceX, so certification might be fairly quick and be able to include any FH launches irregardless of payload configuration.  Same situation for commercial customers.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rsdavis9 on 01/29/2016 02:24 pm
So I heard they were not going to do crossfeed between the boosters on the first launch. So when will they do crossfeed and how much does it gain them.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: fowlyetti on 01/29/2016 02:44 pm
So I heard they were not going to do crossfeed between the boosters on the first launch. So when will they do crossfeed and how much does it gain them.

Im pretty sure they gave up on doing cross feed completely.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Comga on 01/29/2016 03:10 pm
Is there any new info about date of 1st FH launch?

thx

It is still slated for April 2016.

Any information on what the payload will be for the first flight?

I would love to see them send a Dragon on a free return around the moon (with wheel of cheese), but I suspect it will just be a mass simulator.

We have a 363 post thread (http://forum.nasaspaceflight.com/index.php?topic=29768.msg946418#msg946418) on that subject.  No one has posted any information there in two and a half years.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Tuts36 on 01/29/2016 03:52 pm


Any information on what the payload will be for the first flight?

I would love to see them send a Dragon on a free return around the moon (with wheel of cheese), but I suspect it will just be a mass simulator.

We have a 363 post thread (http://forum.nasaspaceflight.com/index.php?topic=29768.msg946418#msg946418) on that subject.  No one has posted any information there in two and a half years.


Well why not?  Someone should call that Chris Bergin fellah, I bet he knows something..
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 01/29/2016 04:18 pm
So I heard they were not going to do crossfeed between the boosters on the first launch. So when will they do crossfeed and how much does it gain them.

Im pretty sure they gave up on doing cross feed completely.

I recall the official line being 'not developing it currently' busy with other things.

Crossfeed came up during the less potent F9V1.0 version.  The F9v1.1 FT has performance that doesn't require Crossfeed.

Although I find the idea super sexy and very appealing, why do it if there aren't any payloads that need the performance and it's not in the long term plan for future vehicles.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 01/29/2016 04:30 pm
So I heard they were not going to do crossfeed between the boosters on the first launch. So when will they do crossfeed and how much does it gain them.

Im pretty sure they gave up on doing cross feed completely.

I recall the official line being 'not developing it currently' busy with other things.

Crossfeed came up during the less potent F9V1.0 version.

No. v1.1 "partial thrust", not v1.0.
For V1.0 version, there were only conceptual talk about "falcon 9 heavy", but nothing officially announced, and no talk about crossfeed.

When Falcon heavy was officially published, it was based on v1.1 version, and crossfeed was announced.

Quote
The F9v1.1 FT has performance that doesn't require Crossfeed.

Although I find the idea super sexy and very appealing, why do it if there aren't any payloads that need the performance and it's not in the long term plan for future vehicles.

yep. Crossfeed is non-trivial to implement and makes things more expensive, and makes recovery of core stage harder. No point of doing it if there are no payloads that require it.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rsdavis9 on 01/29/2016 04:37 pm
So I heard they were not going to do crossfeed between the boosters on the first launch. So when will they do crossfeed and how much does it gain them.

Im pretty sure they gave up on doing cross feed completely.

I recall the official line being 'not developing it currently' busy with other things.

Crossfeed came up during the less potent F9V1.0 version.

No. v1.1 "partial thrust", not v1.0.
For V1.0 version, there were only conceptual talk about "falcon 9 heavy", but nothing officially announced, and no talk about crossfeed.

When Falcon heavy was officially published, it was based on v1.1 version, and crossfeed was announced.

Quote
The F9v1.1 FT has performance that doesn't require Crossfeed.

Although I find the idea super sexy and very appealing, why do it if there aren't any payloads that need the performance and it's not in the long term plan for future vehicles.

yep. Crossfeed is non-trivial to implement and makes things more expensive, and makes recovery of core stage harder. No point of doing it if there are no payloads that require it.

But in the long run. Like when they go interplanetary. Any extra performance without major manufacturing changes is very good.

Yes it is non trivial. But it is just extra tubes and connections and not different tanks or engines.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rsdavis9 on 01/29/2016 04:39 pm
crossfeed. I kind of think of it as a 1.1ft upgrade level of change.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 01/29/2016 05:02 pm
So I heard they were not going to do crossfeed between the boosters on the first launch. So when will they do crossfeed and how much does it gain them.

Im pretty sure they gave up on doing cross feed completely.

I recall the official line being 'not developing it currently' busy with other things.

Crossfeed came up during the less potent F9V1.0 version.

No. v1.1 "partial thrust", not v1.0.
For V1.0 version, there were only conceptual talk about "falcon 9 heavy", but nothing officially announced, and no talk about crossfeed.

When Falcon heavy was officially published, it was based on v1.1 version, and crossfeed was announced.

Quote
The F9v1.1 FT has performance that doesn't require Crossfeed.

Although I find the idea super sexy and very appealing, why do it if there aren't any payloads that need the performance and it's not in the long term plan for future vehicles.

yep. Crossfeed is non-trivial to implement and makes things more expensive, and makes recovery of core stage harder. No point of doing it if there are no payloads that require it.

But in the long run. Like when they go interplanetary. Any extra performance without major manufacturing changes is very good.

Yes it is non trivial. But it is just extra tubes and connections and not different tanks or engines.

ISTM the Raptor upper stage will add more BEO performance than crossfeed would have, and USAF is partially paying for it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RoboGoofers on 01/29/2016 05:04 pm
Yes it is non trivial. But it is just extra tubes and connections and not different tanks or engines.

it IS non trivial, meaning it is NOT just extra tubes, etc.

They decided that they'd rather spend the engineer's man-hours on BFR and Raptor. Cleaner fuel, fewer staging events, greater performance and efficiency.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: andrewsdanj on 01/29/2016 10:16 pm
My understanding of the current 'working theory' on BFR is that it'll be a single-stick in the 10-15 metre diameter range, with no planned three-stick version. In that case any crossfeed would be for FHFT only and would be an evolutionary dead end.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/29/2016 11:01 pm
For fun I was looking at just how high a performance gain could an FH be extended. I ended with a FH with crossfeed using an Raptor 5.2m US which is expended and all three cores expended but still maintaining the engine out margins (no engine out margins would have even higher payload sizes): LEO 115mt and GTO-1800 37mt. This vehicle could do whatever an SLS 1B could do. Obviously the FH would never reach this high because as the weights increase so do the structural weights for strength increase and the gravity losses increase with higher GLOWs. But the addition of 300Klbs (the Raptor US is 60% of this increase in weight) to a vehicle with 4.5Mlbf of thrust is only 6.5% on a vehicle whose T/W is greater than 1.2. What this says is that even though there will be a gravity loss impact it will not be that great.

So FH as it exists now has still a lot of growth room before running out of performance options if it is determined if it was needed (or more correctly someone willing to buy it).

Adding a Raptor 5.2m US to an FH could increase the payload sizes by as much as 60%. Now compound this by adding crossfeed which may add up to another 20% and that is a total increase over current possible of 92%. So even if Raptor is only a 30% gain and adding CF is only another 10% gain that would still be a 43% gain in payload size over the current FH (FT) version. Such that a full reusable FH(CF) with reusable Raptor could still deliver the same payloads as the current FH (FT) in the worst case and in better cases possible even as much as 15% more than the current. These upgrades could occur over the next 5 years where a fully reusable FH would be operational for the testing phase of the BFR and MCT prior to them taking over the FH duties (if at all depending on economics). With a fully reusable FH and F9 their slightly higher $/kg prices than BFR/MCT may be offset by the launch on demand with immediate deployment vs the launch in crates and on-orbit final checkout assembly before deployment.

In all I do not think the FH as we see it now is the end point of the FH's performance.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 01/29/2016 11:27 pm
For fun I was looking at just how high a performance gain could an FH be extended. . .

So can I ask you a couple of questions about your assumptions for this:

Falcon booster core propellant mass (I don't know what that is under FT)
Your 5.2 meter diam US dry mass and propellant mass
lastly, but most important to understand your performance comparisons, what is your centre core boost regime without cross feed? how much centre core propellant is left at side booster seperation? When I model this I generally presume that 4 or 5 engines get shut down, then the remaining ones throttle down to 70% all in steps as the side boosters and centre core's propellant load drops. In my modelling in full expendable mode I still have 50% prop load on the centre core without cross feed
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Zed_Noir on 01/30/2016 12:06 am
...
In all I do not think the FH as we see it now is the end point of the FH's performance.

Just for fun. What will be the performance be like if you replace the Raptor Vac with a BE-3U while keeping the same overall upper stage tankage?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/30/2016 12:33 am
For fun I was looking at just how high a performance gain could an FH be extended. . .

So can I ask you a couple of questions about your assumptions for this:

Falcon booster core propellant mass (I don't know what that is under FT)
Your 5.2 meter diam US dry mass and propellant mass
lastly, but most important to understand your performance comparisons, what is your centre core boost regime without cross feed? how much centre core propellant is left at side booster seperation? When I model this I generally presume that 4 or 5 engines get shut down, then the remaining ones throttle down to 70% all in steps as the side boosters and centre core's propellant load drops. In my modelling in full expendable mode I still have 50% prop load on the centre core without cross feed
Raptor 5.2m US
1) same length as current FT US
2) FT US has ~120mt of prop
3) dry weight of expendable Raptor US 9mt, reusable Raptor 13mt (legs and heat shielding plus other items)
4) propellant mass due to volume increase and density decrease is 204mt (2 L/kg KEROLOX vs 2.35 L/kg METHALOX)
5) ISP of Raptor VAC 380

As far as the regimes of the boosters and center core the flights were evaluated by estimating the delta v provided by the 1st stage configuration on a FH v1.1 then reducing that due to the increased weights of the payload and US. Then adding back the deltaV that the US could provide for a given same total delta V varying the payload mass until they became equal. The differences for gravity losses and differences for drag due to the flight profile were not individually modeled neither was the detailed flight regimes of the boosters and center core being that SpaceX already has an optimized solution for their flight profiles. The numbers I arrived at could be much greater or possibly even less (!) than what an optimized vehicle's true performance would be.

The real true item is that because of the Raptor's US prop increase with also an significant ISP increase it creates the large nearly 60% performance boost. Making again the need for doing crossfeed a back burner item. Such that even with losing a lot of that extra performance in order to do reusability with the US it still may have a performance increase over current and be 100% reusable!!!!!!!!!!!

That makes it an economical advantage over current. Which is why the current US doing reusability would not be an economical move. It would increase the $/kg not decrease it.

The other item with the US doing more of the delta V for the ride to orbit makes it even easier to do RTLS of the cores requiring less propellant to do the return burns meaning more propellant is used for its primary purpose of accelerating the US+payload. This effect was only roughly modeled and may have the largest error contribution to the end values.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/30/2016 12:35 am
I think the expendable dry mass for a Raptor US is too high by several tons. More like 6-7 tons expendable, 10-13 tons reusable (some of that is landing propellant mass).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 01/30/2016 12:50 am
In my assumptions for a Raptor US I was assuming slightly longer than the F1.1 US and 220mt of prop in expendable and 210 (reserving 10) in reuse mode with a dry weight of 10t in expendable mode and 18t in reuse (plus the 10t of prop reserved) for a weight penalty on the launch side of 18t total for reuse.

Anyway in my reuse mode (boosters RTLS, centre core downrange) 2nd stage reusable it gives a great advantage over FHE in performance all the way to GTO. You need to run the US in expendable mode for GSO or to have any real advantage for payloads BEO but in those cases the extra 10 tons of fuel and the removal of 8t of reuse hardware are like adding another stage!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/30/2016 01:00 am
I think the expendable dry mass for a Raptor US is too high by several tons. More like 6-7 tons expendable, 10-13 tons reusable (some of that is landing propellant mass).
The current US dry weight is ~6.5mt. The tank surface area growth for the Raptor is 45% and the engine weight growth is ~2.5X. So a 9mt Raptor expendable weight is a good estimate. But one of the most telling items is that the current FT US has a PF of ~95.8% but the Raptor would have a PF of 96.0%. That measly .2% means a lot when it comes to payload performance especially when there is also such a large ISP increase.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 01/30/2016 01:05 am
Methane is less dense than kerosene, so the stage is either going to be a 5.2m upper the same length or they will have to extend the existing length, which will make the rocket extremely tall and skinny.  Also, the towers and support would have to be taller if they make the stage taller. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/30/2016 01:09 am
I think the expendable dry mass for a Raptor US is too high by several tons. More like 6-7 tons expendable, 10-13 tons reusable (some of that is landing propellant mass).
The current US dry weight is ~6.5mt...
Citation, please. From my best guess, that's probably 2 tons too high.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/30/2016 01:27 am
I think the expendable dry mass for a Raptor US is too high by several tons. More like 6-7 tons expendable, 10-13 tons reusable (some of that is landing propellant mass).
Yes when I was doing the models on the delta V and propelant reserves I enev evaluated a Raptor going all the way to GSO and then returning. The astonishing item was that it could put into GSO what the current FH can put into GSO but it could also return! That got me thinking about just how big of payload an all up expendable FH with Raptor could put into LEO. But the only disadvantage of the FH doing such huge payloads is the faring diameter and volume. It is just not big enough for even the 53mt payload that have been discussed except for propellant tanker duty.

A BTW the 220mt prop load and 13mt dry weight (landing kit) Raptor US if fully refueled in LEO would have without any payload 10.7 km/s delta V. This is enough to go and land on the Moon and almost return to LEO.  ;D
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 01/30/2016 01:31 am
I think the expendable dry mass for a Raptor US is too high by several tons. More like 6-7 tons expendable, 10-13 tons reusable (some of that is landing propellant mass).
The current US dry weight is ~6.5mt...
Citation, please. From my best guess, that's probably 2 tons too high.
Unfortunately there are not any reliable source for the weight other than Wiki which uses the 6.5. If it is indeed too high then the payload weight increases and for the reuse of US case increase even more significantly. But I would rather be a little pessimistic than too wildly optimistic in estimating.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/30/2016 02:27 am
Other estimates I've seen give about 4-4.5 tons dry mass for v1.1 upper, so I'd say about 4.5 tons for FT, and (including the higher thrust and thus probably heavier Raptor) 6-7 for Raptor. That's without better manufacturing techniques like composites.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 01/30/2016 01:02 pm
I think the expendable dry mass for a Raptor US is too high by several tons. More like 6-7 tons expendable, 10-13 tons reusable (some of that is landing propellant mass).
Yes when I was doing the models on the delta V and propelant reserves I enev evaluated a Raptor going all the way to GSO and then returning. The astonishing item was that it could put into GSO what the current FH can put into GSO but it could also return! That got me thinking about just how big of payload an all up expendable FH with Raptor could put into LEO. But the only disadvantage of the FH doing such huge payloads is the faring diameter and volume. It is just not big enough for even the 53mt payload that have been discussed except for propellant tanker duty.

A BTW the 220mt prop load and 13mt dry weight (landing kit) Raptor US if fully refueled in LEO would have without any payload 10.7 km/s delta V. This is enough to go and land on the Moon and almost return to LEO.  ;D

Thanks for these analyses!!!

This upper stage is the vehicle that could be configured for a tanker, cargo carrier, or mini-MCT (1/5th scale or so).  If anyone is interested in exploration near term, this is the ticket.  We don't have to wait decades.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: watermod on 01/30/2016 07:40 pm
Would this possible FH Raptor based 2nd stage be usable or worthwhile on an FT first stage?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 01/30/2016 08:24 pm
Would this possible FH Raptor based 2nd stage be usable or worthwhile on an FT first stage?

USAF wants it to be developed for both F9 and FH

http://www.defense.gov/News/Contracts/Contract-View/Article/642983
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 01/30/2016 08:58 pm
Would this possible FH Raptor based 2nd stage be usable or worthwhile on an FT first stage?

USAF wants it to be developed for both F9 and FH

http://www.defense.gov/News/Contracts/Contract-View/Article/642983

Actually it simply says developing an engine for the upper stage of an F9 or FH, what was linked to had no words about actually developing the upper stage just the engine.

It would be a new and additional contract to develop any sort of Raptor based upper stage, and at that time it might be decided that it was an upper stage for just one of the two, or two different upper stages for the two different boosters. And of course no further contract could be forthcoming. Finally the next contract might be for a Raptor for sea level use with or without specifying what booster it was being designed for. As it is this contract is just for engine development and I would interpret the "for the Falcon 9 or Falcon Heavy upper stage" as being already oversimplified since the existing stage can not use methane.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rpapo on 01/30/2016 09:04 pm
Actually it simply says developing an engine for the upper stage of an F9 or FH, what was linked to had no words about actually developing the upper stage just the engine.
And the document itself was only in support of a relatively small grant to help in the development of said engine.  If the contract had been to make a whole new upper stage, the value of the contract would have had to be much larger.

Relatively small as the industry goes.  I wouldn't mind having just 2-3% of it to fully fund my retirement...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 01/30/2016 09:57 pm
This upper stage is the vehicle that could be configured for a tanker, cargo carrier, or mini-MCT (1/5th scale or so).  If anyone is interested in exploration near term, this is the ticket.  We don't have to wait decades.

I agree, which is why I started this thread:
http://forum.nasaspaceflight.com/index.php?topic=39477.0
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Bynaus on 01/30/2016 10:26 pm
"Falcon Heavy will launch towards the end of the year, possibly late summer" - according to Elon, when answering questions at the Hyperloop design competition (it was a streamed event, so no video yet).

So it seems like Mars is definetly out as a "secret/surprise" target for the Demo mission. Well, there is still the Moon, there is still hope... :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 01/31/2016 04:47 am
"Falcon Heavy will launch towards the end of the year, possibly late summer" - according to Elon, when answering questions at the Hyperloop design competition (it was a streamed event, so no video yet).

So it seems like Mars is definetly out as a "secret/surprise" target for the Demo mission. Well, there is still the Moon, there is still hope... :)
Why is that? They could pick a slower route to Mars... And Falcon Heavy should have performance to spare to use a non-optimal late-window launch slot.

A deep space flight of an unmanned Dragon 2, perhaps landing on the Moon or perhaps returning back to Earth from a loop around the Moon, would also be useful in expanding Dragon 2's reentry envelope and also proving it they can land effectively on other celestial bodies (a difficult feat itself and good precursor to Mars). We shall see.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Bynaus on 01/31/2016 11:44 am
"Falcon Heavy will launch towards the end of the year, possibly late summer" - according to Elon, when answering questions at the Hyperloop design competition (it was a streamed event, so no video yet).

So it seems like Mars is definetly out as a "secret/surprise" target for the Demo mission. Well, there is still the Moon, there is still hope... :)
Why is that? They could pick a slower route to Mars... And Falcon Heavy should have performance to spare to use a non-optimal late-window launch slot.

A deep space flight of an unmanned Dragon 2, perhaps landing on the Moon or perhaps returning back to Earth from a loop around the Moon, would also be useful in expanding Dragon 2's reentry envelope and also proving it they can land effectively on other celestial bodies (a difficult feat itself and good precursor to Mars). We shall see.

Whether FH has enough excess delta-v to still make a Mars-transit in late summer would have to be looked at in more detail.

A free return flight of an unmanned Dragon 2 however would seem possible with only minimal additional work, whereas a Moon landing would require substantial modification of the Dragon 2 (e.g., to accomodate additional fuel). It would be an impressive stunt if it works, but at the same time I don't think Musk would want to spend too much effort on this, so I don't think we will see an unmanned Moon landing.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Johnnyhinbos on 01/31/2016 11:52 am
Elon Musk made a surprise appearance at the SpaceX Hyperloop competition yesterday and during his talk said that FH is NET "end of the year / late summer".

Credit to /u/zucal for link to a recording of the live stream. Apparently Elon stated this at :58, but I couldn't scroll through the video

http://m.ustream.tv/channel/uAPmkVhqjrx
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: 2552 on 01/31/2016 02:02 pm
Elon's talk at the Hyperloop Pod Competition Award Ceremony is on youtube.

https://www.youtube.com/watch?v=ab2VVp1GfmA

Q&A starts at 3:33 (https://youtu.be/ab2VVp1GfmA?t=213), FH question at 30:42 (https://youtu.be/ab2VVp1GfmA?t=1842).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomTX on 01/31/2016 02:17 pm


My question and concern is with a proposed Raptor upper stage using metholox.  Someone has already figured a 5.2m diameter stage the same length as the existing kerolox upper stage to really improve performance, second stage recovery, or both.  5.2 meter means it would have to be made at a new factory near river or ocean going barge transport, or near the launch pad.   River transportation in America is thousands of miles, the best in the world, so this new wider upper stage can be made almost anywhere.

Why do you think that a 5.2m diameter stage needs to be barged or flown? In Texas you can go up to 5.75m high, 6.0 meters wide and 38 meters long* without even having a human review the routing. You just use the automated routing software online. Big stuff like wind tower segments, tanks and refinery parts get moved around pretty frequently on Texas roads.

http://www.txdmv.gov/oversize-weight-permits/route-inspections

Sure, that doesn't give you a lot of ground clearance - but you can go bigger/higher with loads, you just need to get a human to review them. When I went through McGregor a few weeks ago (nothing on the test stands) - there wasn't any obvious impediment to large diameter loads on the roads. You would need pilot vehicles.

Build a 5.2m Raptor based upper somewhere in Texas, drive it to McGregor, drive it to Boca Chica.

Putting a Raptor based upper on a FH in a few years seems like a great way to start getting flight time on Raptor without having to build a whole new rocket. Yes, it adds some complexity, but not as much as building a whole separate Raptor-based first stage and second stage. The additional potential payload is nice too.

*Okay, the rules are actually in feet, but we were using meters.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 01/31/2016 02:30 pm
I think the expendable dry mass for a Raptor US is too high by several tons. More like 6-7 tons expendable, 10-13 tons reusable (some of that is landing propellant mass).
The current US dry weight is ~6.5mt...
Citation, please. From my best guess, that's probably 2 tons too high.
Unfortunately there are not any reliable source for the weight other than Wiki which uses the 6.5. If it is indeed too high then the payload weight increases and for the reuse of US case increase even more significantly. But I would rather be a little pessimistic than too wildly optimistic in estimating.

I have seen the 4.5t number at this location:
http://spacelaunchreport.com/falcon9ft.html
( see the "vehicle components" table about halfway down the article)

There is no reference as to where it came from, and I find it a little bit questionable that it lists the F1.1 S2 dry mass at 6t, but now the F9 FT version has been reduced to 4.5t?  I know they've gotten a lot of extra performance from the first stage, so maybe that enabled them to shrink S2.  Reducing S2 dry mass by 1.5t to 2.0t without changing dimension seems unlikley.

Using that S2 dry mass does agree with simulations of F9 FT putting a 5.5t mass into GTO, which is the speculated capability of F9 FT.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RonM on 01/31/2016 03:04 pm


My question and concern is with a proposed Raptor upper stage using metholox.  Someone has already figured a 5.2m diameter stage the same length as the existing kerolox upper stage to really improve performance, second stage recovery, or both.  5.2 meter means it would have to be made at a new factory near river or ocean going barge transport, or near the launch pad.   River transportation in America is thousands of miles, the best in the world, so this new wider upper stage can be made almost anywhere.

Why do you think that a 5.2m diameter stage needs to be barged or flown? In Texas you can go up to 5.75m high, 6.0 meters wide and 38 meters long* without even having a human review the routing. You just use the automated routing software online. Big stuff like wind tower segments, tanks and refinery parts get moved around pretty frequently on Texas roads.

http://www.txdmv.gov/oversize-weight-permits/route-inspections

Sure, that doesn't give you a lot of ground clearance - but you can go bigger/higher with loads, you just need to get a human to review them. When I went through McGregor a few weeks ago (nothing on the test stands) - there wasn't any obvious impediment to large diameter loads on the roads. You would need pilot vehicles.

Build a 5.2m Raptor based upper somewhere in Texas, drive it to McGregor, drive it to Boca Chica.

Putting a Raptor based upper on a FH in a few years seems like a great way to start getting flight time on Raptor without having to build a whole new rocket. Yes, it adds some complexity, but not as much as building a whole separate Raptor-based first stage and second stage. The additional potential payload is nice too.

*Okay, the rules are actually in feet, but we were using meters.

Good point about road transport in Texas. Build, test, and launch all Raptor US from Texas and there's no problem.

Build and test in Texas, then ship via barge on the Intercoastal Waterway to Florida if needed there.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 01/31/2016 03:22 pm
Good point about road transport in Texas. Build, test, and launch all Raptor US from Texas and there's no problem.

Build and test in Texas, then ship via barge on the Intercoastal Waterway to Florida if needed there.

Good points. But the starting point of this discussion as I understand, was at least initially those stages would be built in Hawthorne, where the engineering is and where the expertise in building carbon composite components is. As those stages are expected to be reusable, transport cost would not be too important. They could get the qualification stage "somehow" to McGregor for qualification testing and do static fires of operational stages at the launch site. An airport is right adjacent to the factory and if they prefer to ship it a harbour is near too. For that distance a helicopter could lift it. It should not be too hard to build a second stage test frame for the launch pad.

Once there is a BFR factory established, production could move there.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: CuddlyRocket on 01/31/2016 04:02 pm
Elon's talk at the Hyperloop Pod Competition Award Ceremony is on youtube.

Elon said that the F9 could send 3-4 tons to Mars and the FH could send 12-13 tons.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomTX on 01/31/2016 04:36 pm
Good point about road transport in Texas. Build, test, and launch all Raptor US from Texas and there's no problem.

Build and test in Texas, then ship via barge on the Intercoastal Waterway to Florida if needed there.

Good points. But the starting point of this discussion as I understand, was at least initially those stages would be built in Hawthorne, where the engineering is and where the expertise in building carbon composite components is. As those stages are expected to be reusable, transport cost would not be too important. They could get the qualification stage "somehow" to McGregor for qualification testing and do static fires of operational stages at the launch site. An airport is right adjacent to the factory and if they prefer to ship it a harbour is near too. For that distance a helicopter could lift it. It should not be too hard to build a second stage test frame for the launch pad.

Once there is a BFR factory established, production could move there.

You can drive a 5.2m 2nd stage in other states, it's just that Texas makes it easy, online and automated.

Example:

http://www.dot.ca.gov/hq/traffops/permits/pdf_documents/elln/ellntables_082001.pdf

So, I'm perfectly happy if everything happens in Texas, easier for me to go see it ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RAN on 01/31/2016 05:59 pm
The Planetary Society posted this update regarding their LightSail spacecraft on January 29th.  They mention a launch of FH in September 2016 with a dual payload of LightSail and Prox-1.  Could this be the demo payload?

Quote
LightSail is scheduled to be delivered to Georgia Tech for integration into the Prox-1 spacecraft later that month. The duo are manifested for a SpaceX Falcon Heavy flight in September 2016, pending launch vehicle readiness.

Or is it expected that the demo payload will not be a paying customer.

http://www.planetary.org/blogs/jason-davis/2016/20160129-lightsail-b-sail-deployment.html?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: geza on 01/31/2016 06:21 pm
Prox-1 is a nanosat, not a major payload:
http://www.css.gatech.edu/projects.html
It will perform proximity operations with its expended launcher and with "additional objects". Prox-1 will also deploy the solar sail and inspects its deplyment:
http://www.ssdl.gatech.edu/

We still don't know, whether the first FH will lauch something bigger. Probably not...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 01/31/2016 06:30 pm
Light sail is not on the demo launch, it's on the flight after that.  Sept 2016 is what they've been saying for months for the lightsail mission, it doesn't account for the latest delays to the demo flight.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RAN on 01/31/2016 07:55 pm
Thanks for the info.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: watermod on 01/31/2016 11:04 pm
Elon Musk made a surprise appearance at the SpaceX Hyperloop competition yesterday and during his talk said that FH is NET "end of the year / late summer".

Credit to /u/zucal for link to a recording of the live stream. Apparently Elon stated this at :58, but I couldn't scroll through the video

http://m.ustream.tv/channel/uAPmkVhqjrx

(http://vignette4.wikia.nocookie.net/peanuts/images/a/a0/1107charlie_brown_lucy_football.jpg/revision/latest?cb=20100523172400) ?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Johnnyhinbos on 01/31/2016 11:22 pm

Elon Musk made a surprise appearance at the SpaceX Hyperloop competition yesterday and during his talk said that FH is NET "end of the year / late summer".

Credit to /u/zucal for link to a recording of the live stream. Apparently Elon stated this at :58, but I couldn't scroll through the video

http://m.ustream.tv/channel/uAPmkVhqjrx

(http://vignette4.wikia.nocookie.net/peanuts/images/a/a0/1107charlie_brown_lucy_football.jpg/revision/latest?cb=20100523172400) ?
Now THAT was funny! LOL!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Retired Downrange on 02/03/2016 06:26 pm
Quote from:
Re: Pad 39A - Transition to SpaceX Falcon Heavy debut - Thread 2
« Reply #192 on: Today at 01:57 PM »

Jeff Foust ‏@jeff_foust  7m7 minutes ago
Shotwell: we have completed and activated LC-39A for F9 and Falcon Heavy missions.

Jeff Foust ‏@jeff_foust  2m2 minutes ago
Shotwell: we’ll post updated Falcon Heavy performance numbers later this week/early next week.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mme on 02/03/2016 06:35 pm
https://twitter.com/jeff_foust/status/694955310465818624 (https://twitter.com/jeff_foust/status/694955310465818624):
Quote
Shotwell: Falcon Heavy recovery plans drives all sorts of requirements at the range; with 3 booster cores returning.
That will be such a site to see.  :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Marslauncher on 02/03/2016 07:20 pm
Hah - Per Gwynne Shotwell, Falcon 9 Heavy will look at cross fed a year or two after first flight, unclear if 60 tonnes to orbit is something that customers need yet.

Ramp up to 30 cores per year by the end of this year, currently have 6 processing lanes now for cores.

Oh also confirmation the F9(FT) legs are beefier and more robust.

Let the crossfeed talk continue!

https://www.youtube.com/watch?v=y_aF3WOfSJY&feature=youtu.be
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 02/03/2016 07:38 pm
Hah - Per Gwynne Shotwell, Falcon 9 Heavy will look at cross fed a year or two after first flight, unclear if 60 tonnes to orbit is something that customers need yet.

Is that what they're saying FT disposable with cross feed will get, or what FT disposable with cross feed and Raptor US will get?

If that's with the Merlin US and Raptor US gets even more, they're moving into SLS comparable territory.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TrevorMonty on 02/03/2016 07:46 pm
Hah - Per Gwynne Shotwell, Falcon 9 Heavy will look at cross fed a year or two after first flight, unclear if 60 tonnes to orbit is something that customers need yet.

Is that what they're saying FT disposable with cross feed will get, or what FT disposable with cross feed and Raptor US will get?
60t likely to be for current FH full thrust version, v1.1 was 53t.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/03/2016 08:07 pm
Someone figured with expendable FH FT cores 81 tons.  Don't know if that is with or without cross feed.  That is a lot of payload. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mongo62 on 02/03/2016 08:15 pm
Someone figured with expendable FH FT cores 81 tons.  Don't know if that is with or without cross feed.  That is a lot of payload.

Could 60t be with all three FT cores being recovered, as indicated by Jeff Foust's tweet, and a Raptor expendable US?

Shotwell: Falcon Heavy recovery plans drives all sorts of requirements at the range; with 3 booster cores returning.

Implying that if they use cross-feed and expend the center core, then it is definitely in SLS territory, but at a FAR lower cost.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/03/2016 08:36 pm
Yes, can't wait till this thing blasts off.  Hopefully they can get the Raptor upper stage engine running in a year or two, then build the larger upper stage. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 02/03/2016 09:11 pm
Someone figured with expendable FH FT cores 81 tons.  Don't know if that is with or without cross feed.  That is a lot of payload.

Could 60t be with all three FT cores being recovered, as indicated by Jeff Foust's tweet, and a Raptor expendable US?

Shotwell: Falcon Heavy recovery plans drives all sorts of requirements at the range; with 3 booster cores returning.

Implying that if they use cross-feed and expend the center core, then it is definitely in SLS territory, but at a FAR lower cost.

If they use x-feed, Raptor US, and expend everything, this could put them closer to Block IIB than to Block I, and still far lower in price. If they fly one like that, Hatch, Shelby, et. al. may not be able to prevent SLS' demise.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Endeavour_01 on 02/03/2016 09:36 pm
Could 60t be with all three FT cores being recovered, as indicated by Jeff Foust's tweet, and a Raptor expendable US?

It seems the comment was 60 mt with crossfeed and all cores expended. Not sure how much a Raptor US would add.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 02/03/2016 09:52 pm
Someone figured with expendable FH FT cores 81 tons.  Don't know if that is with or without cross feed.  That is a lot of payload.

"Somebody" has also said that earth is flat.

v1.1 without crossfeed was 40 tonnes, with crossfeed 53 tonnes.
FT version of F9 gets 30% more to GTO than v1.1 version of F9 mostly due more propellant in second stage, but also due more thrust(less gravity losses during 1st stage) and slightly more 1st stage fuel. Gains to LEO are smaller, so the heavy is propably about 50 tonnes to LEO.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 02/03/2016 10:32 pm
It seems the comment was 60 mt with crossfeed and all cores expended. Not sure how much a Raptor US would add.

Jeff Foust ‏@jeff_foust  2m2 minutes ago
Shotwell: we’ll post updated Falcon Heavy performance numbers later this week/early next week.

I know this isn't the space policy section, but I hope two things happen.

1) They post what fully expendable w/ X-feed and Raptor US will do and what it will cost.

2) That comes up in presidential debates re. NASA and HSF.

It would be nice for the candidates to do some thinking about and some debating around the deep space HSF program. It would be engaging to hear them debate whether NASA should be freed from SLS and allowed to work with SX through space act agreements towards some achievable and affordable goals.

Since replies here take the thread OT, I have started a new thread in the Space Policy section to discuss this:

http://forum.nasaspaceflight.com/index.php?topic=39508.0
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/03/2016 10:33 pm
http://forum.nasaspaceflight.com/index.php?topic=39310.msg1481719#msg1481719

This somebody is "oldatlas_Eguy". 

Quote:

"Using the T/W of 125, Thrust of 550klbf, 5.2m diameter tank of same length as M1D tank, and ISP of 380 I get for 3 core RTLS FHFT which can theoretically do 40mt with a Raptor US could do 58mt 3 core RTLS. As expendable max FHFT can do ~58mt so with raptor 81mt. With margins for engine out 53mt, Raptor 75mt. (estimates)"
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Hotblack Desiato on 02/03/2016 10:36 pm
Could 60t be with all three FT cores being recovered, as indicated by Jeff Foust's tweet, and a Raptor expendable US?

It seems the comment was 60 mt with crossfeed and all cores expended. Not sure how much a Raptor US would add.

How wide can the payload be? If a FH can deliver a maximum of 60 or even 80 or more tons to LEO, then the possible shape will become more and more important. >60t, yet no more than 5m wide? That would be interesting for large quantities of cargo, either fuel or packaged goods like food and equipment.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/03/2016 10:43 pm
All payloads since Shuttle started back in 1981 were designed to fit the Shuttle cargo bay, which was a little less than 5m wide x 18m long.  Atlas V, Delta IV and SpaceX use a fairing to handle 5m payloads.  Anything wider will take a wider fairing which is not impossible.  Atlas and Delta had plans for wider ones, but they never had a need.  Even the Bigelow 330 module can fit in a 5m or the 5.2m fairing of Falcon Heavy.  I think 6m or maybe 7m is possible on top of a 5.2m upper stage, but may not be necessary for a long time.  Assembly in space of 5m wide components can build a large NautilusX spacecraft for a Mars mission or lunar mission, or a huge space station using Bigelow 330 modules.  Even the SLS with an upper stage, payloads will only be about 5m wide or slightly more unless they build a wider upper stage.   
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 02/03/2016 10:44 pm
I know this isn't the space policy section, but I hope two things happen.

1) They post what fully expendable w/ X-feed and Raptor US will do and what it will cost.

I think it is far too early to get anything about a Raptor US from SpaceX either in numbers or even general description.  In fact I am still not all that sure it will ever happen. The funding agreement with the USAF is for an engine that could be used in an F9/FH upper stage, not for an upper stage.

I would be very happy though if we got numbers for these 4 configurations FH3RTLS, FH3R with centre core ASDS recovery, FH2RTLS centre core expended, and FHE. And if they gave us the throttling regime on the centre core in all those cases. I am still not convinced cross feed is worth the effort.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/03/2016 10:59 pm
Why would the Air-Force want a new upper stage engine, if they didn't want an upper stage on some rocket?  Currently there are only two active upper stage engines, the RL-10 and the vacuum Merlin.  RL-10's are expensive and limited in power.  Merlin has power but is low on ISP.  So the Air-Force wants a new upper engine, more powerful than the RL-10 but higher ISP than Merlin.  So a new upper stage can be used on Falcon Heavy or even sold to ULA for an upper stage for Vulcan.  Make's sense since Vulcan is to be metholox.  Raptor is to be metholox.  Making the tankage 5.2m for a new upper stage is the easy part, building the vacuum Raptor is the hard part.  SpaceX doesn't mind taking the Air-Force's money to help.  More might come in the next few years to finish it. 

Check out my link above for the "numbers".  I know they are not from SpaceX and the SpaceX website is way behind in their numbers. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 02/03/2016 11:10 pm
Why would the Air-Force want a new upper stage engine, if they didn't want an upper stage on some rocket?  Currently there are only two active upper stage engines, the RL-10 and the vacuum Merlin.  RL-10's are expensive and limited in power.  Merlin has power but is low on ISP.  So the Air-Force wants a new upper engine, more powerful than the RL-10 but higher ISP than Merlin.  So a new upper stage can be used on Falcon Heavy or even sold to ULA for an upper stage for Vulcan.  Make's sense since Vulcan is to be metholox.  Raptor is to be metholox.  Making the tankage 5.2m for a new upper stage is the easy part, building the vacuum Raptor is the hard part.  SpaceX doesn't mind taking the Air-Force's money to help.  More might come in the next few years to finish it. 

Check out my link above for the "numbers".  I know they are not from SpaceX and the SpaceX website is way behind in their numbers.

I have those numbers, and ones I have made up for FT and those for a methalox 5M upper stage (a little longer than the existing one) but I won't bother redoing my performance model and sharing it with numbers that I made up or that someone else conjured up. I have played with it for my purposes, but I am seriously interested in the SpaceX numbers when they come out over the next week or two. Particularly if they have revised ISP too.

The USAF has made a lot of development agreements that have gone nowhere, I think there is a reasonable chance (at least 50%) that the RaptorVac will be built but that there is no F9/FH stage built for it ever. And I seriously doubt whether the AF gets anyone else to manufacture a stage built on it, even if the development agreement allows for it.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Hotblack Desiato on 02/03/2016 11:14 pm
Maybe the funding of the raptor US engine is just a thumbscrew for ULA?

A monopoly is not the ideal situation for the air force, having an additional supplier is always a good idea, even if the air force is never going to use it, just the option that they could do it adds a leverage at negotiations.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/04/2016 12:30 am
SpaceX, in order to get the money, are spending more on this engine than the Air Force, so they must be serious about it's development.  They do want to go to Mars and will need it for MCT or and upper stage for the BFR.  This money would help speed that along. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: llanitedave on 02/04/2016 01:00 am
It seems the comment was 60 mt with crossfeed and all cores expended. Not sure how much a Raptor US would add.

Jeff Foust ‏@jeff_foust  2m2 minutes ago
Shotwell: we’ll post updated Falcon Heavy performance numbers later this week/early next week.

I know this isn't the space policy section, but I hope two things happen.

1) They post what fully expendable w/ X-feed and Raptor US will do and what it will cost.

2) That comes up in presidential debates re. NASA and HSF.

It would be nice for the candidates to do some thinking about and some debating around the deep space HSF program. It would be engaging to hear them debate whether NASA should be freed from SLS and allowed to work with SX through space act agreements towards some achievable and affordable goals.

Since replies here take the thread OT, I have started a new thread in the Space Policy section to discuss this:

http://forum.nasaspaceflight.com/index.php?topic=39508.0 (http://forum.nasaspaceflight.com/index.php?topic=39508.0)


Since many of us can't post in Space Policy, I'll just state here that a presidential debate on the topic now would not be very productive, as the candidates are almost certainly all woefully uninformed about the subject.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Geron on 02/04/2016 01:15 am
Does anyone have a copy of the video of Shotwell making statements about falcon 9/heavy at the ISDC in DC?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/04/2016 01:22 am
Does anyone have a copy of the video of Shotwell making statements about falcon 9/heavy at the ISDC in DC?
Here's a link to Shotwell's talk:
She's on at 2:43:00
https://www.youtube.com/watch?v=2cT7_iySwP8
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 02/04/2016 01:26 am
And an article with highlights:

Quote
SpaceX also plans this year to conduct the first test flight of the Falcon Heavy rocket, a larger variant of the Falcon 9 that has two additional boosters strapped to its sides. Like the Falcon 9, the Falcon Heavy is also meant to be reusable at some point. However, its recovery will be much more complicated, since it will require landing three boosters instead of just one. Shotwell said SpaceX will post updated performance numbers for the Falcon Heavy within the next few weeks.

http://news.yahoo.com/spacex-modify-falcon-9-rocket-200232767.html;_ylt=A0LEVoC5tbJWOsUA3IoPxQt.;_ylu=X3oDMTByMjB0aG5zBGNvbG8DYmYxBHBvcwMxBHZ0aWQDBHNlYwNzYw--
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH on 02/04/2016 08:56 am
With a 50T capacity, it could launch two BA330 at once...width is OK, but having trouble finding launch lengths, so that might be a limiting factor.

Instant SpaceStation(t).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: starsilk on 02/04/2016 03:38 pm
Why would the Air-Force want a new upper stage engine, if they didn't want an upper stage on some rocket?  Currently there are only two active upper stage engines, the RL-10 and the vacuum Merlin.  RL-10's are expensive and limited in power.  Merlin has power but is low on ISP.  So the Air-Force wants a new upper engine, more powerful than the RL-10 but higher ISP than Merlin.  So a new upper stage can be used on Falcon Heavy or even sold to ULA for an upper stage for Vulcan.  Make's sense since Vulcan is to be metholox.  Raptor is to be metholox.  Making the tankage 5.2m for a new upper stage is the easy part, building the vacuum Raptor is the hard part.  SpaceX doesn't mind taking the Air-Force's money to help.  More might come in the next few years to finish it. 

also J-2X. quite a lot of money was spent on that recently...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Burninate on 02/04/2016 04:23 pm
Does anyone have a copy of the video of Shotwell making statements about falcon 9/heavy at the ISDC in DC?
Here's a link to Shotwell's talk:
She's on at 2:43:00
https://www.youtube.com/watch?v=2cT7_iySwP8
Asked directly about updated Falcon Heavy numbers.  "we'll post updated figures later this week or early next week".  No crossfeed at the beginning, but still on the table for later.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TrueBlueWitt on 02/04/2016 05:27 pm
Gwenn refused to give numbers but did say she didn't have any costumers asking for "60 tons" right now.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: notsorandom on 02/04/2016 06:44 pm
Could 60t be with all three FT cores being recovered, as indicated by Jeff Foust's tweet, and a Raptor expendable US?

It seems the comment was 60 mt with crossfeed and all cores expended. Not sure how much a Raptor US would add.

How wide can the payload be? If a FH can deliver a maximum of 60 or even 80 or more tons to LEO, then the possible shape will become more and more important. >60t, yet no more than 5m wide? That would be interesting for large quantities of cargo, either fuel or packaged goods like food and equipment.
This is something that is important yet rarely gets mentioned when talking about how much mass Falcon Heavy can lift. We are familiar with the concept of the cargo on Dragon being volume rather than mass limited. From the Oct 2015 user guide I worked out that the Falcon fairing has about 700 cubic meters of space. To lift a full 53mt of payload the density of the payload mass to fairing volume would have to be greater than 75 kg per cubic meter. For a payload of 60mt it would have to be greater than 85 kg per cubic meter and for 80mt 114 kg per cubic meter. John Shannon mentioned when he was presenting tot he Augustine Committee that most payloads have the density of balsa wood. The problem is that balsa wood varies greatly in density between 64 to 160 kg per cubic meter. Still it does kinda give a nebulous frame of reference for when the Falcon Heavy might become limited by volume. They could also make a bigger fairing but they really want to keep commonality between the two Falcon variants. Also this is for LEO only. Payloads riding to higher energy trajectories will be lighter and should have plenty of room.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/04/2016 06:47 pm
I guess people are thinking that if you have a large tonnage size, things like fuel for depots, structures for habitats, and such could be built or loaded in LEO for deep space travel or large space stations.  Then you are limited by volume. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Hotblack Desiato on 02/04/2016 07:23 pm
Could 60t be with all three FT cores being recovered, as indicated by Jeff Foust's tweet, and a Raptor expendable US?

It seems the comment was 60 mt with crossfeed and all cores expended. Not sure how much a Raptor US would add.

How wide can the payload be? If a FH can deliver a maximum of 60 or even 80 or more tons to LEO, then the possible shape will become more and more important. >60t, yet no more than 5m wide? That would be interesting for large quantities of cargo, either fuel or packaged goods like food and equipment.
This is something that is important yet rarely gets mentioned when talking about how much mass Falcon Heavy can lift. We are familiar with the concept of the cargo on Dragon being volume rather than mass limited. From the Oct 2015 user guide I worked out that the Falcon fairing has about 700 cubic meters of space. To lift a full 53mt of payload the density of the payload mass to fairing volume would have to be greater than 75 kg per cubic meter. For a payload of 60mt it would have to be greater than 85 kg per cubic meter and for 80mt 114 kg per cubic meter. John Shannon mentioned when he was presenting tot he Augustine Committee that most payloads have the density of balsa wood. The problem is that balsa wood varies greatly in density between 64 to 160 kg per cubic meter. Still it does kinda give a nebulous frame of reference for when the Falcon Heavy might become limited by volume. They could also make a bigger fairing but they really want to keep commonality between the two Falcon variants. Also this is for LEO only. Payloads riding to higher energy trajectories will be lighter and should have plenty of room.

Yes, especially the last sentence is my conclusion too. That rocket would be beyond 20t TxI (TLI, TMI, whatever). Raises the question, what reentry speeds would a reusable upper stage accept? Bring some cargo on a highly elliptical orbit, and let it do the last burn with an internal small rocket motor. The US will then come back with 10-11 km/s reentryspeed (maybe a bit less, if it can perform a slight retroburn, on the other hand, it could do an aerobraking flight through the atmosphere).

The other reason for this high value, which leads to a long and rather thin payload shape is: FH is not intended to be used fully expendable. At least not for LEO.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 02/04/2016 08:35 pm
I guess people are thinking that if you have a large tonnage size, things like fuel for depots, structures for habitats, and such could be built or loaded in LEO for deep space travel or large space stations.  Then you are limited by volume.

Not sure what you mean? 
The current 5.2m fairing is approximately 200m3.
Even filled with liquid methane only, it would mass 85tonnes; with Lox, 228tonnes.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 02/04/2016 08:43 pm
There is only 26 days until the 1st of March. 1 March would be a good point for a schedule of a major info release about FH (FT).  This is just over 3 weeks from now. It would also be several days after hopefully SES-9 has successfully launched.

Not only will it be hard waiting on the SES-9 launch but on the FH info release. Hopefully they give 4 sets of info:
1) RTLS all 3 cores LEO
2) RTLS all 3 cores GTO
3) Expendable  all 3 cores LEO
4) Expendable all 3 cores GTO

These four give the corners of the performance box defined by LEO vs GTO and RTLS 3 core vs expendable 3 core.

And if we are lucky they will also accompany the performance info with some new pricing info.

It will be informative to find out how far off our estimates have been as to what they consider the normal (with margins) payload capabilities are.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/04/2016 08:44 pm
I mean the larger tonnage delivered to LEO would be the items I listed.  I know fuel and lox will probably weigh far more than anything except maybe lithium batteries, especially lox.  I do agree a 5.2 meter space is a lot of space.  Limited volume would probably be for things like large solar panels, or large structures like large habitats, then space might be limited.   Even if the tonnage is 60, two Bigelow 330 modules weigh 40 tons, but may not fit in the current space of the existing FH fairing.  That is why maybe a larger fairing might be needed to match the tonnage of certain items. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 02/04/2016 08:46 pm
There is only 26 days until the 1st of March. 1 March would be a good point for a schedule of a major info release about FH (FT).  This is just over 3 weeks from now. It would also be several days after hopefully SES-9 has successfully launched.

Not only will it be hard waiting on the SES-9 launch but on the FH info release. Hopefully they give 4 sets of info:
1) RTLS all 3 cores LEO
2) RTLS all 3 cores GTO
3) Expendable  all 3 cores LEO
4) Expendable all 3 cores GTO

These four give the corners of the performance box defined by LEO vs GTO and RTLS 3 core vs expendable 3 core.

And if we are lucky they will also accompany the performance info with some new pricing info.

It will be informative to find out how far off our estimates have been as to what they consider the normal (with margins) payload capabilities are.
I think it is really important to differentiate how much performance improvement you get with putting the centre core on an ASDS and how little penalty there is if you are expending the centre core but RTLSing the side boosters.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 02/04/2016 09:52 pm
There is only 26 days until the 1st of March. 1 March would be a good point for a schedule of a major info release about FH (FT).  This is just over 3 weeks from now. It would also be several days after hopefully SES-9 has successfully launched.

Not only will it be hard waiting on the SES-9 launch but on the FH info release. Hopefully they give 4 sets of info:
1) RTLS all 3 cores LEO
2) RTLS all 3 cores GTO
3) Expendable  all 3 cores LEO
4) Expendable all 3 cores GTO

These four give the corners of the performance box defined by LEO vs GTO and RTLS 3 core vs expendable 3 core.

And if we are lucky they will also accompany the performance info with some new pricing info.

It will be informative to find out how far off our estimates have been as to what they consider the normal (with margins) payload capabilities are.
I think it is really important to differentiate how much performance improvement you get with putting the centre core on an ASDS and how little penalty there is if you are expending the centre core but RTLSing the side boosters.
If they give every thing we would like to have then there would be a table with

LEO, GTO, TLI, TMI, C3 across the top and

RTLS 3 core,
RTLS boosters ASDS center,
RTLS boosters center expended,
ASDS boosters center expended and
all expended

down the side. Not only payload size but pricing as well and I will jump for joy because mission straw-mans for Lunar or Mars can be costed accurately instead of the estimates based on other estimates.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 02/04/2016 10:18 pm
There is only 26 days until the 1st of March. 1 March would be a good point for a schedule of a major info release about FH (FT).  This is just over 3 weeks from now. It would also be several days after hopefully SES-9 has successfully launched.

Not only will it be hard waiting on the SES-9 launch but on the FH info release. Hopefully they give 4 sets of info:
1) RTLS all 3 cores LEO
2) RTLS all 3 cores GTO
3) Expendable  all 3 cores LEO
4) Expendable all 3 cores GTO

These four give the corners of the performance box defined by LEO vs GTO and RTLS 3 core vs expendable 3 core.

And if we are lucky they will also accompany the performance info with some new pricing info.

It will be informative to find out how far off our estimates have been as to what they consider the normal (with margins) payload capabilities are.
I think it is really important to differentiate how much performance improvement you get with putting the centre core on an ASDS and how little penalty there is if you are expending the centre core but RTLSing the side boosters.
If they give every thing we would like to have then there would be a table with

LEO, GTO, TLI, TMI, C3 across the top and

RTLS 3 core,
RTLS boosters ASDS center,
RTLS boosters center expended,
ASDS boosters center expended and
all expended

down the side. Not only payload size but pricing as well and I will jump for joy because mission straw-mans for Lunar or Mars can be costed accurately instead of the estimates based on other estimates.

I simply want to calibrate my model
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 02/04/2016 10:27 pm
Not sure what you mean? 
The current 5.2m fairing is approximately 200m3.
Even filled with liquid methane only, it would mass 85tonnes; with Lox, 228tonnes.

.. and filled with steel it'd be 1600 tons. i.e., if you were building steel structures in space, using FH to launch the raw materials would give you 7.5 m3 of material per launch. That giant fairing would be mostly empty, suggesting you'd be wise to form it into less dense beams and girders or whatever.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 02/04/2016 10:32 pm
If a Raptor upper stage becomes real, and its diameter is 5.2 meters as has been speculated, could FH then handle a 7ish meter and longer (15-18m) fairing?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TrueBlueWitt on 02/04/2016 10:55 pm
Wouldn't the best plan for building structures in space.. be to send raw material and use a 3d printer?  Then existing fairing would be more than adequate. Correct?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 02/04/2016 10:59 pm
Wouldn't the best plan for building structures in space.. be to send raw material and use a 3d printer?  Then existing fairing would be more than adequate. Correct?

It'd be fun to find out.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/04/2016 11:03 pm
Yes, it would be 520 tons of aluminum.  So any fairing larger than what they have would have to be for extremely light materials.  So the 5.2m x 13m fairing they now use should be adequate for most anything currently being launched or planned even one Bigelow 330 module.  The F9 FT with a new Raptor upper stage might even be able to handle a Bigelow 330 module by itself.  LOX seems to be the heaviest bulk item for a depot that could be launched.  I see now why making lox on the moon out of regolith might be cheaper than launching it from earth to a L1 station. 

IF they lengthened the fairing to 15-18m it would be about the same size as the shuttle cargo bay.  This would probably only happen with a new upper stage though for extremely large but light payloads. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 02/05/2016 12:03 am

There is only 26 days until the 1st of March. 1 March would be a good point for a schedule of a major info release about FH (FT).  This is just over 3 weeks from now. It would also be several days after hopefully SES-9 has successfully launched.

Not only will it be hard waiting on the SES-9 launch but on the FH info release. Hopefully they give 4 sets of info:
1) RTLS all 3 cores LEO
2) RTLS all 3 cores GTO
3) Expendable  all 3 cores LEO
4) Expendable all 3 cores GTO

These four give the corners of the performance box defined by LEO vs GTO and RTLS 3 core vs expendable 3 core.

And if we are lucky they will also accompany the performance info with some new pricing info.

It will be informative to find out how far off our estimates have been as to what they consider the normal (with margins) payload capabilities are.
I think it is really important to differentiate how much performance improvement you get with putting the centre core on an ASDS and how little penalty there is if you are expending the centre core but RTLSing the side boosters.
If they give every thing we would like to have then there would be a table with

LEO, GTO, TLI, TMI, C3 across the top and

RTLS 3 core,
RTLS boosters ASDS center,
RTLS boosters center expended,
ASDS boosters center expended and
all expended

down the side. Not only payload size but pricing as well and I will jump for joy because mission straw-mans for Lunar or Mars can be costed accurately instead of the estimates based on other estimates.

Dream on. :) They've never released that kind of performance detail for anything, what makes you think try will now?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sewebster on 02/05/2016 12:11 am
Dream on. :) They've never released that kind of performance detail for anything, what makes you think try will now?

So I guess you're saying you don't expect them to just release the source code for their calculations?  :(
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 02/05/2016 12:20 am
Dream on. :) They've never released that kind of performance detail for anything, what makes you think try will now?

So I guess you're saying you don't expect them to just release the source code for their calculations?  :(
Look I would be happy with the ISP and important mass elements for the new cores and upper stage as well as ISP and thrust data for the FT engines as long as they either describe the throttling profile of the centre stage and give at least performance of all expendable, centre core expendable side core RTLS, centre core ASDS side core RTLS and all RTLS.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/05/2016 12:31 am
I'd be happy if they just updated the numbers here:
http://elvperf.ksc.nasa.gov
...to include F9FT, Heavy, and most of the reuse/expendable variants like they show all the different Atlas V variants.

I'd also like if they updated it for Atlas V dual Centaur and the latest Delta IV Heavy variant.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 02/05/2016 12:35 am
I'd be happy if they just updated the numbers here:
http://elvperf.ksc.nasa.gov
...to include F9FT, Heavy, and most of the reuse/expendable variants like they show all the different Atlas V variants.

I'd also like if they updated it for Atlas V dual Centaur and the latest Delta IV Heavy variant.

I don't think SpaceX could update that site - nor do they have the numbers for Atlas and Delta I don't think - or who is the "they" you are referring to.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/05/2016 12:38 am
NASA
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 02/05/2016 02:09 am
Not sure what you mean? 
The current 5.2m fairing is approximately 200m3.
Even filled with liquid methane only, it would mass 85tonnes; with Lox, 228tonnes.

.. and filled with steel it'd be 1600 tons. i.e., if you were building steel structures in space, using FH to launch the raw materials would give you 7.5 m3 of material per launch. That giant fairing would be mostly empty, suggesting you'd be wise to form it into less dense beams and girders or whatever.

I was responding to:
I guess people are thinking that if you have a large tonnage size, things like fuel for depots, structures for habitats, and such could be built or loaded in LEO for deep space travel or large space stations.  Then you are limited by volume.

Wasn't sure what spacenut was saying... if you are hauling dense payloads (fuel, steel, water...), then the FH would be mass limited, not limited by volume.  Still confused (but used to it).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/05/2016 02:21 am
They can always make a bigger fairing, just like the similarly-sized (in diameter) Atlas V has a 7.2m fairing as an option (that no one has ever ordered). But almost none of our spacecraft infrastructure is built for more than 5m diameter payloads, and shipping such enormous payloads is an enormous pain since you pretty much can't even use an airplane (limited to about 7m, and even then it's like a single aircraft that you'd have to rely on, at least in the US).

I think the whole "volume-limited" thing is overdone. 5m is fine, and you DON'T need a bigger launch vehicle to use a bigger-than-5m fairing.

Also, where the heck would you TEST such a huge fairing? As it is, 5m fairings barely fit at Plum Brook, which has the largest vacuum chamber in the world.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sdsds on 02/05/2016 02:27 am
Once the first FH vehicle has lifted from the pad we'll likely know a bit more about the cost (to SpaceX) of launching FH. Only then will we know, for easily divisible payloads like propellant or water, whether a single FH launch is more cost effective than multiple F9FT launches. I think Shotwell knows her potential customers well, and if she doesn't have any asking for 60 tons right now, she is prudent to defer public comment about that capability and how it might be priced.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sewebster on 02/05/2016 03:07 am
Also, where the heck would you TEST such a huge fairing? As it is, 5m fairings barely fit at Plum Brook, which has the largest vacuum chamber in the world.

Isn't the vacuum chamber 100' in diameter and taller than that? The acoustic facility is smaller...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 02/05/2016 06:26 am
Dream on. :) They've never released that kind of performance detail for anything, what makes you think try will now?

So I guess you're saying you don't expect them to just release the source code for their calculations?  :(
Look I would be happy with the ISP and important mass elements for the new cores and upper stage as well as ISP and thrust data for the FT engines as long as they either describe the throttling profile of the centre stage and give at least performance of all expendable, centre core expendable side core RTLS, centre core ASDS side core RTLS and all RTLS.

Do you want them to release a cure for cancer while they are at it?...  ::) No one in the business releases that level of detail.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 02/05/2016 01:39 pm
Dream on. :) They've never released that kind of performance detail for anything, what makes you think try will now?

So I guess you're saying you don't expect them to just release the source code for their calculations?  :(
Look I would be happy with the ISP and important mass elements for the new cores and upper stage as well as ISP and thrust data for the FT engines as long as they either describe the throttling profile of the centre stage and give at least performance of all expendable, centre core expendable side core RTLS, centre core ASDS side core RTLS and all RTLS.

Do you want them to release a cure for cancer while they are at it?...  ::) No one in the business releases that level of detail.

No, I think the chance of them curing cancer is a little lower than the chance of them putting the ULA numbers up on a NASA website mentioned above.

Seriously were were promised updated FHFT numbers, I want enough to model as accurately as I can.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: StuffOfInterest on 02/05/2016 02:29 pm
One thing to keep in mind with all this discussion of larger payload fairings is road transport.  I doubt anything over the current size is going to be able to fit on the road in halves.  Will quarter slices get you back to small enough?  That adds more complexity.  Of course, there has been no mention of any actual payloads out there requiring larger than what is available now so much of this discussion is just burning pixels for fun.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: matthewkantar on 02/05/2016 02:38 pm
You could ship it in quarters but have it split in half at sep the same way the smaller fairings do. The flange and fasteners would make it a little heavier, but you could road ship some really big fairings in quarters without having to reinvent the sep event.

Matthew
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: McDew on 02/05/2016 02:44 pm
Yes, and the URL was NASA.gov. Thought that'd be sufficient for individuals capable of independent thought.

The best numbers we ever got for 1.1 came from there, came from NASA. I hope it is updated with full thrust and Falcon Heavy numbers.
The NASA site reflects the vehicle configurations and contractual performance offered by the contractors for the NLS-II IDIQ contract.  Contractors can only propose new offerings once a year during the on-ramp period (nominally each August).  Don't expect the numbers or configurations on the NASA site to change until after the next on-ramp/evaluation period.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 02/05/2016 02:46 pm
Yes, and the URL was NASA.gov. Thought that'd be sufficient.

The best numbers we ever got for 1.1 came from there, came from NASA. I hope it is updated with full thrust and Falcon Heavy numbers.

I got the numbers from spaceflight 101, the SpaceX web site and wikipedia - can you give me a more specific link on that site at NASA because I couldn't find data from there, just a web form for calculating performance (which is aspx and if I go view source I don't see the numbers it makes its calculations from)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/05/2016 03:00 pm
Yes, and the URL was NASA.gov. Thought that'd be sufficient.

The best numbers we ever got for 1.1 came from there, came from NASA. I hope it is updated with full thrust and Falcon Heavy numbers.

I got the numbers from spaceflight 101, the SpaceX web site and wikipedia - can you give me a more specific link on that site at NASA because I couldn't find data from there, just a web form for calculating performance (which is aspx and if I go view source I don't see the numbers it makes its calculations from)
Yes, you must actually calculate performance to a reference orbit of your choosing. That's better than Wikipedia (obviously), SpaceX (doesn't provide full orbit parameters and reserves some undefined amount of performance for reuse, according to Shotwell), and spaceflight101 (which isn't a primary source).

And because it gives you performance numbers to many different orbits, you can use it to calibrate your model much better than just giving a couple reference orbits (especially when it's "GTO" without specifying 1500 or 1800m/s-to-go)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/05/2016 03:21 pm
Yes, and the URL was NASA.gov. Thought that'd be sufficient for individuals capable of independent thought.

The best numbers we ever got for 1.1 came from there, came from NASA. I hope it is updated with full thrust and Falcon Heavy numbers.
The NASA site reflects the vehicle configurations and contractual performance offered by the contractors for the NLS-II IDIQ contract.  Contractors can only propose new offerings once a year during the on-ramp period (nominally each August).  Don't expect the numbers or configurations on the NASA site to change until after the next on-ramp/evaluation period.
That's a good point, however:

V1.1 was added before it was even flown. Full thrust has already flown. TESS, a NASA payload awarded under NLS (I believe) will necessarily fly on a Full Thrust because v1.1 is retired. This implies that Full Thrust is available through NLS somehow.

...so I think it odd that it hasn't already been updated publicly.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 02/05/2016 03:28 pm
Yes, you must actually calculate performance to a reference orbit of your choosing. That's better than Wikipedia (obviously), SpaceX (doesn't provide full orbit parameters and reserves some undefined amount of performance for reuse, according to Shotwell), and spaceflight101 (which isn't a primary source).

And because it gives you performance numbers to many different orbits, you can use it to calibrate your model much better than just giving a couple reference orbits (especially when it's "GTO" without specifying 1500 or 1800m/s-to-go)

But it does not give me the information I need to calculate anything. How can I use the calculation on this page to check my model of calculations if I don't know the masses they are assuming? Is the reference model in their calculations one with legs?

Back when the first TMI numbers went up on the SpaceX website I could use that with the data on SII engine performance and SII masses (wikipedia, spaceflight 101 and also the SpaceX website) to backwards calculate the speed the FH lofted the 2nd stage to in fully expendable mode. That gave me one point of sanity check for my model of FH operation.  This doesn't really give me any without knowing the numbers they used.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: anonymousgerbil on 02/05/2016 03:31 pm
I found something in the newest F9 user's guide (dated Oct 21st 2015) that perplexed me a bit, especially in regards to Falcon heavy:

Quote
SpaceX uses one of two PAFs on the launch vehicle, based on payload mass. The light PAF can accommodate payloads weighing up to 3,453 kg (7,612 lb), while the heavy PAF can accommodate up to 10,886 kg (24,000 lb).

Would this imply that for payloads greater than 10,886 kg a new PAF would be required?  Seems odd that they can't even max out the single stick with these 2 PAFs, let alone the FH LEO numbers.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/05/2016 03:35 pm
I found something in the newest F9 user's guide (dated Oct 21st 2015) that perplexed me a bit, especially in regards to Falcon heavy:

Quote
SpaceX uses one of two PAFs on the launch vehicle, based on payload mass. The light PAF can accommodate payloads weighing up to 3,453 kg (7,612 lb), while the heavy PAF can accommodate up to 10,886 kg (24,000 lb).

Would this imply that for payloads greater than 10,886 kg a new PAF would be required?  Seems odd that they can't even max out the single stick with these 2 PAFs, let alone the FH LEO numbers.
The only thing heavier than 10t is Dragon for Falcon 9. Everything else is much lighter. Not many heavy payloads need to launch to LEO.

This is the Falcon 9 user's guide, not the Heavy's.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: anonymousgerbil on 02/05/2016 03:37 pm
I found something in the newest F9 user's guide (dated Oct 21st 2015) that perplexed me a bit, especially in regards to Falcon heavy:

Quote
SpaceX uses one of two PAFs on the launch vehicle, based on payload mass. The light PAF can accommodate payloads weighing up to 3,453 kg (7,612 lb), while the heavy PAF can accommodate up to 10,886 kg (24,000 lb).

Would this imply that for payloads greater than 10,886 kg a new PAF would be required?  Seems odd that they can't even max out the single stick with these 2 PAFs, let alone the FH LEO numbers.
The only thing heavier than 10t is Dragon for Falcon 9. Everything else is much lighter. Not many heavy payloads need to launch to LEO.

This is the Falcon 9 user's guide, not the Heavy's.

The new user's guide covers both F9 and FH:  http://www.spacex.com/sites/spacex/files/falcon_9_users_guide_rev_2.0.pdf

Edit:  it at least somewhat talks about FH, doesn't seem to be comprehensive though.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 02/05/2016 04:52 pm
Yes, you must actually calculate performance to a reference orbit of your choosing. That's better than Wikipedia (obviously), SpaceX (doesn't provide full orbit parameters and reserves some undefined amount of performance for reuse, according to Shotwell), and spaceflight101 (which isn't a primary source).

And because it gives you performance numbers to many different orbits, you can use it to calibrate your model much better than just giving a couple reference orbits (especially when it's "GTO" without specifying 1500 or 1800m/s-to-go)

But it does not give me the information I need to calculate anything. How can I use the calculation on this page to check my model of calculations if I don't know the masses they are assuming? Is the reference model in their calculations one with legs?

Back when the first TMI numbers went up on the SpaceX website I could use that with the data on SII engine performance and SII masses (wikipedia, spaceflight 101 and also the SpaceX website) to backwards calculate the speed the FH lofted the 2nd stage to in fully expendable mode. That gave me one point of sanity check for my model of FH operation.  This doesn't really give me any without knowing the numbers they used.
The values given by the orbit query is based on no margins (including no legs). No margins means no engine out either. The 1350 LEO and GTO values for v1.1 given by SpaceX included engine out margins + maybe a little more as well as attached legs and other recovery hardware margins. The two values gives the percentages or delta V/energy values for the stage deltas for no margins vs ASDS recovery for the v1.1. Now for FT we do not have any values.

Plus I do not think the numbers in the NASA query model will give you any answers since they are most likely a polynomial algorithm that given certain inputs returns an output. They may have no relationship to masses of stages or engine thrusts ISPs or anything else just a complex curve equation.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 02/05/2016 05:09 pm
Removed some squabbling about where stuff was or will be posted. Please assume good faith, and remember, be excellent to each other.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/05/2016 05:30 pm
Yes, you must actually calculate performance to a reference orbit of your choosing. That's better than Wikipedia (obviously), SpaceX (doesn't provide full orbit parameters and reserves some undefined amount of performance for reuse, according to Shotwell), and spaceflight101 (which isn't a primary source).

And because it gives you performance numbers to many different orbits, you can use it to calibrate your model much better than just giving a couple reference orbits (especially when it's "GTO" without specifying 1500 or 1800m/s-to-go)

But it does not give me the information I need to calculate anything. How can I use the calculation on this page to check my model of calculations if I don't know the masses they are assuming? Is the reference model in their calculations one with legs?

Back when the first TMI numbers went up on the SpaceX website I could use that with the data on SII engine performance and SII masses (wikipedia, spaceflight 101 and also the SpaceX website) to backwards calculate the speed the FH lofted the 2nd stage to in fully expendable mode. That gave me one point of sanity check for my model of FH operation.  This doesn't really give me any without knowing the numbers they used.
The values given by the orbit query is based on no margins (including no legs). No margins means no engine out either. The 1350 LEO and GTO values for v1.1 given by SpaceX included engine out margins + maybe a little more as well as attached legs and other recovery hardware margins. The two values gives the percentages or delta V/energy values for the stage deltas for no margins vs ASDS recovery for the v1.1. Now for FT we do not have any values.

Plus I do not think the numbers in the NASA query model will give you any answers since they are most likely a polynomial algorithm that given certain inputs returns an output. They may have no relationship to masses of stages or engine thrusts ISPs or anything else just a complex curve equation.
Or sure, but you can use it to back out realistic values for all those things and to test your model. If you know lift-off mass, Isp, thrust, and payload to multiple orbits, you could actually back out dry masses, especially for a simple vehicle.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 02/05/2016 05:48 pm
Yes, you must actually calculate performance to a reference orbit of your choosing. That's better than Wikipedia (obviously), SpaceX (doesn't provide full orbit parameters and reserves some undefined amount of performance for reuse, according to Shotwell), and spaceflight101 (which isn't a primary source).

And because it gives you performance numbers to many different orbits, you can use it to calibrate your model much better than just giving a couple reference orbits (especially when it's "GTO" without specifying 1500 or 1800m/s-to-go)

But it does not give me the information I need to calculate anything. How can I use the calculation on this page to check my model of calculations if I don't know the masses they are assuming? Is the reference model in their calculations one with legs?

Back when the first TMI numbers went up on the SpaceX website I could use that with the data on SII engine performance and SII masses (wikipedia, spaceflight 101 and also the SpaceX website) to backwards calculate the speed the FH lofted the 2nd stage to in fully expendable mode. That gave me one point of sanity check for my model of FH operation.  This doesn't really give me any without knowing the numbers they used.
The values given by the orbit query is based on no margins (including no legs). No margins means no engine out either. The 1350 LEO and GTO values for v1.1 given by SpaceX included engine out margins + maybe a little more as well as attached legs and other recovery hardware margins. The two values gives the percentages or delta V/energy values for the stage deltas for no margins vs ASDS recovery for the v1.1. Now for FT we do not have any values.

Plus I do not think the numbers in the NASA query model will give you any answers since they are most likely a polynomial algorithm that given certain inputs returns an output. They may have no relationship to masses of stages or engine thrusts ISPs or anything else just a complex curve equation.
Or sure, but you can use it to back out realistic values for all those things and to test your model. If you know lift-off mass, Isp, thrust, and payload to multiple orbits, you could actually back out dry masses, especially for a simple vehicle.
Algebra gives us that given two solutions with two equations you can solve for 1 unknown. With three solutions you can solve for 2 unknowns ... Pick orbits that give you solvable for unknowns equations and you can back out all the data to the same level of accuracy that the solutions are given (looks to be 3 significant digits, maybe 4). You can do the back out analysis with a simple Basic program that iterates the unknown values until it matches up with the given solutions.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: fthomassy on 02/05/2016 06:18 pm
Algebra gives us that given two solutions with two equations you can solve for 1 unknown. With three solutions you can solve for 2 unknowns ... Pick orbits that give you solvable for unknowns equations and you can back out all the data to the same level of accuracy that the solutions are given (looks to be 3 significant digits, maybe 4). You can do the back out analysis with a simple Basic program that iterates the unknown values until it matches up with the given solutions.
One unknown can be solved per simultaneous equation.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 02/05/2016 06:34 pm
Algebra gives us that given two solutions with two equations you can solve for 1 unknown. With three solutions you can solve for 2 unknowns ... Pick orbits that give you solvable for unknowns equations and you can back out all the data to the same level of accuracy that the solutions are given (looks to be 3 significant digits, maybe 4). You can do the back out analysis with a simple Basic program that iterates the unknown values until it matches up with the given solutions.
One unknown can be solved per simultaneous equation.
Thank you, I got carried away with the plethora of unknowns.

Having the extra equation/answer helps in unknown value solution validation. I do the hunt for unknowns a lot of times by the iterative process by hand using a spreadsheet. Mainly where looking for payload sizes in a two part (destinations with different payloads same vehicle) problems such as landing on the Moon and then returning.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: fthomassy on 02/05/2016 06:41 pm
One unknown can be solved per simultaneous equation.
Thank you, I got carried away with the plethora of unknowns.

Having the extra equation/answer helps in unknown value solution validation. [snip]
Agreed, more data is more better :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomTX on 02/07/2016 08:44 pm
One thing to keep in mind with all this discussion of larger payload fairings is road transport.  I doubt anything over the current size is going to be able to fit on the road in halves.  Will quarter slices get you back to small enough?  That adds more complexity.  Of course, there has been no mention of any actual payloads out there requiring larger than what is available now so much of this discussion is just burning pixels for fun.

5.2 meter diameter is road transportable within Texas. All you have to do is use the automated routing software on the State website and pay the appropriate oversize/overweight fee, use required pilot cars and such. You don't even need a human review/signoff of your routing.

It's not trivial, but big stuff for oil refineries, wind towers, et cetera gets moved on the road with some frequency.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Geron on 02/09/2016 07:11 am
Does anyone know the name of the music that plays at the end of the commercial space dev conference?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/10/2016 01:44 am
Someone on another thread calculated to get a high ISP on a Raptor upper stage engine the diameter of the nozzle would be 4.8m.  Therefore it makes sense to have a 5.2m or slightly larger upper stage so the upper stage engine can be protected during launch by the interstage collar as well as a nice transition to the fairing. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Donosauro on 02/10/2016 03:12 pm
Also, where the heck would you TEST such a huge fairing? As it is, 5m fairings barely fit at Plum Brook, which has the largest vacuum chamber in the world.

Isn't the vacuum chamber 100' in diameter and taller than that? The acoustic facility is smaller...

Yep, 100 feet in diameter, 122 feet high. But the loading doors are only 15.2 m (50 ft) square.

http://www.grc.nasa.gov/WWW/Facilities/ext/spf/index.html
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/10/2016 05:09 pm
Also, you have to actually test separation dynamics, and then you have to carefully slow down the fairing so it doesn't bang into your expensive thermal vacuum chamber.

Look at the tests they do with 5m fairings. There's not exactly a ton of extra room.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sewebster on 02/10/2016 06:28 pm
Also, you have to actually test separation dynamics, and then you have to carefully slow down the fairing so it doesn't bang into your expensive thermal vacuum chamber.

Look at the tests they do with 5m fairings. There's not exactly a ton of extra room.

Cool, thanks for the clarification. Here is a video link for those who hadn't seen it (like me): https://www.youtube.com/watch?v=LtI1V624vWM
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Ronsmytheiii on 02/11/2016 12:15 am
Also, you have to actually test separation dynamics, and then you have to carefully slow down the fairing so it doesn't bang into your expensive thermal vacuum chamber.

Look at the tests they do with 5m fairings. There's not exactly a ton of extra room.

They have done bigger shrouds in the past (Skylab shroud seen in Plum Brook below)

http://grin.hq.nasa.gov/ABSTRACTS/GPN-2000-001462.html
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/11/2016 12:25 am
Also, you have to actually test separation dynamics, and then you have to carefully slow down the fairing so it doesn't bang into your expensive thermal vacuum chamber.

Look at the tests they do with 5m fairings. There's not exactly a ton of extra room.

They have done bigger shrouds in the past (Skylab shroud seen in Plum Brook below)

http://grin.hq.nasa.gov/ABSTRACTS/GPN-2000-001462.html
Indeed.
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720022228.pdf
But notice that didn't cover the whole of Skylab, only a portion of it (the top part). Also, they had to assemble the fairing you see in that picture in two chunks, a top and a bottom. That'd be impractical for the huge composite fairings you see in SLS diagrams.

...additionally, that was significantly narrower at 6.6m in diameter vs the 8+m you see quoted for the SLS fairing (let alone the 10 and 12m fairings, the last one being almost twice as wide!), as well as shorter than the typical notional fairings (even though it still needed to be assembled out of two pieces!).


...it is possible to shoehorn it in there, but it is by no means terribly practical and would likely add weight to the fairing due to the need to assemble it inside the chamber.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: vapour_nudge on 02/11/2016 01:46 pm
Looks like they've lost the Viasat-2 launch due to the FH delays  It has been redirected to Arianespace
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 02/11/2016 01:51 pm
Looks like they've lost the Viasat-2 launch due to the FH delays  It has been redirected to Arianespace

Was to be expected - it's probably not going to be the last FH payload they lose.

Whilst I appreciate payload providers supporting rockets that have not yet launched and putting their money where their mouth is whilst doing so, It's not as sane a choice as putting your super-expensive future-insurance of a satellite on a rocket that has a concrete launch history.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/11/2016 02:03 pm
Yeah it is, otherwise they'd be stuck with high prices forever. Without a rational willingness to try new rockets on the part of the customers, the price will never come down. It's perfectly sane to book early on a new rocket an then change if the rocket is delayed more than you are willing to tolerate. Both actions are perfectly sane and rational.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Nilof on 02/11/2016 05:12 pm
What about building a fairing test rig on a reused first stage, and trying out the new fairing on a suborbital flight?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 02/11/2016 05:30 pm
What about building a fairing test rig on a reused first stage, and trying out the new fairing on a suborbital flight?

Only if the test can replicate the same conditions as the regular flight
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 02/11/2016 05:34 pm
What about building a fairing test rig on a reused first stage, and trying out the new fairing on a suborbital flight?

Only if the test can replicate the same conditions as the regular flight
In addition, you would also need to expend a brand-new second stage.  We're starting to talk about a very expensive test by this point.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Nilof on 02/11/2016 06:34 pm
In addition, you would also need to expend a brand-new second stage.  We're starting to talk about a very expensive test by this point.

I was thinking of suborbital flight with just the first stage and a structural prototype on top. No second stage, everything fully reusable.

What about building a fairing test rig on a reused first stage, and trying out the new fairing on a suborbital flight?

Only if the test can replicate the same conditions as the regular flight

That is likely the main issue. To be comparable to a thermovac chamber, the stage would have to provide a similar altitude profile to the actual launch. I don't know exactly how much delta-v would be necessary for that and if it's feasible for a reusable stage. Acceleration doesn't necessarily need to be simulated too closely though, since vacuum chambers don't simulate that at all.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 02/11/2016 06:48 pm

That is likely the main issue. To be comparable to a thermovac chamber, the stage would have to provide a similar altitude profile to the actual launch. I don't know exactly how much delta-v would be necessary for that and if it's feasible for a reusable stage. Acceleration doesn't necessarily need to be simulated too closely though, since vacuum chambers don't simulate that at all.

Yes, vacuum chambers do sim gravity.  They will put springs on the fairing.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: PahTo on 02/11/2016 06:54 pm

That is likely the main issue. To be comparable to a thermovac chamber, the stage would have to provide a similar altitude profile to the actual launch. I don't know exactly how much delta-v would be necessary for that and if it's feasible for a reusable stage. Acceleration doesn't necessarily need to be simulated too closely though, since vacuum chambers don't simulate that at all.

Yes, vacuum chambers do sim gravity.  They will put springs on the fairing.

Good stuff--thanks Jim.  Do the springs dynamically actuate to provide more and less load to mimic the loads experienced during an ascent profile, or just go with max expected at any point?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 02/11/2016 06:56 pm

Good stuff--thanks Jim.  Do the springs dynamically actuate to provide more and less load to mimic the loads experienced during an ascent profile, or just go with max expected at any point?

Just during the separation event.  Also, I meant they simulate acceleration and not gravity
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 02/11/2016 09:50 pm
Yeah it is, otherwise they'd be stuck with high prices forever. Without a rational willingness to try new rockets on the part of the customers, the price will never come down. It's perfectly sane to book early on a new rocket an then change if the rocket is delayed more than you are willing to tolerate. Both actions are perfectly sane and rational.

Delays cost money.

Quote from: Peter B. de Selding
ViaSat's Dankberg: ViaSat-2 should generate $40-$50M rev per month - 10x that of a conventional sat, so launch schedule is crucial for us. - source (https://twitter.com/pbdes/status/697324482483060738)

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 02/11/2016 10:39 pm

That is likely the main issue. To be comparable to a thermovac chamber, the stage would have to provide a similar altitude profile to the actual launch. I don't know exactly how much delta-v would be necessary for that and if it's feasible for a reusable stage. Acceleration doesn't necessarily need to be simulated too closely though, since vacuum chambers don't simulate that at all.

Yes, vacuum chambers do sim gravity.  They will put springs on the fairing.

For reference - Here is a video of a SpaceX fairing test:
https://www.youtube.com/watch?v=LtI1V624vWM
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/11/2016 11:43 pm
Yeah it is, otherwise they'd be stuck with high prices forever. Without a rational willingness to try new rockets on the part of the customers, the price will never come down. It's perfectly sane to book early on a new rocket an then change if the rocket is delayed more than you are willing to tolerate. Both actions are perfectly sane and rational.

Delays cost money.

Quote from: Peter B. de Selding
ViaSat's Dankberg: ViaSat-2 should generate $40-$50M rev per month - 10x that of a conventional sat, so launch schedule is crucial for us. - source (https://twitter.com/pbdes/status/697324482483060738)
...which is exactly why I said that BOTH actions (including the decision to switch to a non-delayed rocket) are rational.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: UberNobody on 02/12/2016 01:43 am
I'm getting anxious now.  Gwynne Shotwell said we'd get a performance update on Falcon Heavy early this week...  It's hard to be patient!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: bstrong on 02/12/2016 01:49 am
I'm getting anxious now.  Gwynne Shotwell said we'd get a performance update on Falcon Heavy early this week...  It's hard to be patient!

I'm assuming Shotwell's plans for the week went out the window with the CRS-8 incident at McGregor. I wouldn't count on hearing anything about Falcon Heavy until that is resolved.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/12/2016 02:22 am
I'm getting anxious now.  Gwynne Shotwell said we'd get a performance update on Falcon Heavy early this week...  It's hard to be patient!

I'm assuming Shotwell's plans for the week went out the window with the CRS-8 incident at McGregor. I wouldn't count on hearing anything about Falcon Heavy until that is resolved.
Way overblown. Not a long-term problem at all, just a (possible) delay on this flight.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 02/12/2016 02:37 am
I'd be surprised if the entire company organically reassess timelines for minor problems. There shouldn't be a correlation between this and FH performance figures - since Shotwell already has the figures, there's nothing to be delayed. She'll release the info at her discretion - I'd say her personal workload would be more impactful.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: llanitedave on 02/12/2016 03:46 am
I'd be surprised if the entire company organically reassess timelines for minor problems. There shouldn't be a correlation between this and FH performance figures - since Shotwell already has the figures, there's nothing to be delayed. She'll release the info at her discretion - I'd say her personal workload would be more impactful.


This short-term delay could certainly have a short-term effect on her workload.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: bstrong on 02/12/2016 01:16 pm
For the record, I wasn't trying to imply we won't hear anything for 6 months. Just, you know, probably not this week and maybe not even next. So I wouldn't sit there hitting refresh all day on Friday waiting for the update.

In every high-performance company I've ever worked at (and notably not at some others), if you have an unexpected problem come up on the critical path of an important project, you can expect managers all the way up to the top to hound-dog it until it is resolved, just to make sure that no one forgets for a second just how important it is to resolve quickly. And in this case, at least one high-maintenance customer will need to be kept in the loop and coordinated with, and even the ones who probably won't be impacted will be calling for updates.

On top of that, Shotwell just got up on stage last week and told the world that SpaceX was about to move to a three week launch cadence. The way you get there is by having a process in place to thoroughly investigate the root cause of every delay and make corrections to ensure similar ones don't happen again. There are probably people working on eliminating delays on the order of hours or minutes, so if something pops up that sets you back by a couple of weeks, that's a really big deal that requires lots of management attention.

To put a number on it, a two week delay in an every-three-weeks launch schedule at $60M per launch (an underestimate) costs $40M in revenue this year plus the potential of lost sales due to perceived issues with launching on time. Even if this particular issue is a one-off fluke, there was a process problem that let it happen, and it needs to be addressed. You also start thinking about whether you need to ramp production sooner than planned so that you can maintain a larger buffer of cores so that even if one hits a snag, it doesn't affect your launch schedule next time.

Now, I don't see this particular issue as being significant in the long-term at SpaceX either, but I guarantee you that even a short-term problem is a big deal at SpaceX right now. Heads are rolling. Shotwell is most definitely busy. Falcon Heavy updates will wait.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: philw1776 on 02/12/2016 04:30 pm
I'm getting anxious now.  Gwynne Shotwell said we'd get a performance update on Falcon Heavy early this week...  It's hard to be patient!

The really bad news is that the premature ejaculation of schedule virus that affects Elon's brain may have spread to Gwynne.   :o

Now maybe she's making premature announcements of future announcements that slip schedule too.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: woods170 on 02/16/2016 02:50 pm
Over-promising and under-delivering has just cost Falcon Heavy a mission:

http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/

And Arianespace just lucked out in filling a hole in their manifest.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Doesitfloat on 02/16/2016 03:20 pm
Over-promising and under-delivering has just cost Falcon Heavy a mission:

http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/

And Arianespace just lucked out in filling a hole in their manifest.

Didn't cost Spacex a mission. ViaSat is using the Falcon Heavy for the ViaSat-3 platform in 2019.
source:
http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html (http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 02/16/2016 03:22 pm
It was a mission trade,

http://spacenews.com/viasat-details-1-4-billion-global-ka-band-satellite-broadband-strategy-to-oust-incumbent-players/#sthash.u5Y3Y1on.dpuf

Quote
>
ViaSat is maintaining its Falcon Heavy launch contract, which will now be used to launch one of the ViaSat-3 satellites around 2020, and has booked a reservation for a future Falcon Heavy, also for ViaSat-3, which is not yet a contract.
>
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: woods170 on 02/16/2016 03:39 pm
Over-promising and under-delivering has just cost Falcon Heavy a mission:

http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/ (http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/)

And Arianespace just lucked out in filling a hole in their manifest.

Didn't cost Spacex a mission. ViaSat is using the Falcon Heavy for the ViaSat-3 platform in 2019.
source:
http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html (http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html)

Any satellite that was planned to fly with SpaceX but instead ends up flying with the competition is a mission lost to SpaceX. Regardless of any shuffling, retaining of contracts, etc. etc.

And then there is this:
Quote from: Peter B. de Selding
Ariane 5 is generally more expensive than SpaceX’s Falcon, but Baldridge said Evry, France-based Arianespace met the company partway to secure the business.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gongora on 02/16/2016 03:43 pm
Over-promising and under-delivering has just cost Falcon Heavy a mission:

http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/

And Arianespace just lucked out in filling a hole in their manifest.

Didn't cost Spacex a mission. ViaSat is using the Falcon Heavy for the ViaSat-3 platform in 2019.
source:
http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html (http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html)

Are you assuming SpaceX wouldn't have won a contract for either of the ViaSat3 payloads after a successful ViaSat2 launch?  That's the only way you can say they didn't lose a mission.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dror on 02/16/2016 04:15 pm
Over-promising and under-delivering has just cost Falcon Heavy a mission:

http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/

And Arianespace just lucked out in filling a hole in their manifest.

Didn't cost Spacex a mission. ViaSat is using the Falcon Heavy for the ViaSat-3 platform in 2019.
source:
http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html (http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html)

Are you assuming SpaceX wouldn't have won a contract for either of the ViaSat3 payloads after a successful ViaSat2 launch?  That's the only way you can say they didn't lose a mission.
They would have won both.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 02/16/2016 04:53 pm
We already had a long discussion of this in the launch manifest thread.  Can we move this there?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 02/16/2016 09:37 pm
That's one way of looking at it. The other way is that for a satellite that generates $50M/month in profit, they never had any intention of flying on the cheaper rocket. i.e., they were just trying to get a better price from Arianespace.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 02/17/2016 10:07 pm
That's one way of looking at it. The other way is that for a satellite that generates $50M/month in profit, they never had any intention of flying on the cheaper rocket. i.e., they were just trying to get a better price from Arianespace.


If the heavy has flown even once maybe it wouldn't have moved.  But technically it's still a paper rocket that has yet to see the light of day.

Customers likely have much more detailed information and they made a business decision.

The long grinding road to FH first flight needs to come to an end soon or they will have more customer losses.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/17/2016 10:47 pm
"Technically" it's not a paper rocket if metal has been bent.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LastStarFighter on 02/17/2016 10:56 pm
"Technically" it's not a paper rocket if metal has been bent.

Have we seen any bent metal yet for the heavy?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 02/17/2016 10:59 pm
"Technically" it's not a paper rocket if metal has been bent.

Have we seen any bent metal yet for the heavy?

A Falcon Heavy is made up of three Falcon 9 1st stage cores and one Falcon 9 2nd stage and fairing.  Except for the attachment hardware and Falcon Heavy specific software, everything else for a Falcon Heavy has already been flight tested.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LastStarFighter on 02/17/2016 11:02 pm
"Technically" it's not a paper rocket if metal has been bent.

Have we seen any bent metal yet for the heavy?

A Falcon Heavy is made up of three Falcon 9 1st stage cores and one Falcon 9 2nd stage and fairing.  Except for the attachment hardware and Falcon Heavy specific software, everything else for a Falcon Heavy has already been flight tested.

So Atlas 5 Heavy isn't a paper rocket either then? And the Angara 7?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 02/17/2016 11:26 pm
"Technically" it's not a paper rocket if metal has been bent.

Have we seen any bent metal yet for the heavy?
Yes, it was on display during the Orbcomm 2 broadcast.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/17/2016 11:30 pm
"Technically" it's not a paper rocket if metal has been bent.

Have we seen any bent metal yet for the heavy?

A Falcon Heavy is made up of three Falcon 9 1st stage cores and one Falcon 9 2nd stage and fairing.  Except for the attachment hardware and Falcon Heavy specific software, everything else for a Falcon Heavy has already been flight tested.

So Atlas 5 Heavy isn't a paper rocket either then? And the Angara 7?
I fully believe they could fly Atlas V Heavy in the timeframe they say they can, if needed and someone pays for it.

...though in this case I mean I'm sure that metal has already been bent for the first Falcon Heavy.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 02/17/2016 11:38 pm
So what do you call a rocket that has been delayed for years and years before getting off the pad for the first time? Seems like that'd be a useful word to describe a lot of rockets.

My suggestion: a DNF (https://en.wikipedia.org/wiki/Duke_Nukem_Forever) rocket.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/17/2016 11:41 pm
So what do you call a rocket that has been delayed for years and years before getting off the pad for the first time? Seems like that'd be a useful word to describe a lot of rockets.
Well /technically/ it's not a paper rocket. I mean, if we're going to throw around words like "technically." Delayed rocket. Forever never rocket. Elon's trinicorn. Musk's Mist.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LastStarFighter on 02/18/2016 12:01 am
"Technically" it's not a paper rocket if metal has been bent.

Have we seen any bent metal yet for the heavy?
Yes, it was on display during the Orbcomm 2 broadcast.

I just rewatched it and I'm not sure I saw it this time either. Do you have a time before launch it was shown at?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 02/18/2016 12:26 am
So Atlas 5 Heavy isn't a paper rocket either then? And the Angara 7?

Using the same definition, no Atlas V Heavy would not be a "paper rocket".  The Angara family is in development, and has done test flights, so no it would not be a "paper rocket" either.

To me, and this is just my definition, a paper rocket would be one that is made of components that have not flown in the intended configuration.  Falcon Heavy, Atlas V Heavy, and Angara 7 all use substantially the same flight hardware as what their single core versions use.

The SpaceX BFR would be a paper rocket, as it's supposedly not using any Falcon family hardware, nor any other flight proven hardware.

The SLS?  Well there are many arguments that can (and have) been made about it...   ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 02/18/2016 12:32 am
Great, terminology aside, the fact remains that you should treat all rockets that haven't flown with some scepticism.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 02/18/2016 12:44 am
The loss of this payload for FH is interesting in a very bad way for SpaceX.   Any bets regarding them further delaying the first launch after this announcement?  This was one of two payloads that fit well to FH's stated capability.  It would have been a revenue generator, and not a loss generator like the first two flights, which are basically a FH test program with low value payloads.

1.  If there are further delays, look for additional customer cancellations or pushing out contracts.
2.  Furthermore, if you can't gain new contracts, conditional contracts, or letters of intent, it pretty much suggests  SpaceX is just being used as a wedge to drive down Ariane 5 pricing.   That may be good strategy in it's own right, but it fails to move any revenue into SpaceX's coffers, and that lost revenue is what matters most.

My guess is if FH first launch slips again, look for SpaceX to cancel the vehicle in late 2016.


Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: llanitedave on 02/18/2016 02:44 am
My guess is that there's a little unnecessary drama going on in this thread.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 02/18/2016 04:15 am


My guess is if FH first launch slips again, look for SpaceX to cancel the vehicle in late 2016.

I will gladly take that bet: that FH will slip again (when do you think the first flight is currently scheduled for?) and that it will *not* be cancelled, whether in late 2016 or anytime else before it flies.

But then, I've got tickets to the second FH launch, so I'm biased. ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 02/18/2016 04:32 am
"Technically" it's not a paper rocket if metal has been bent.

Have we seen any bent metal yet for the heavy?
Yes, it was on display during the Orbcomm 2 broadcast.

I just rewatched it and I'm not sure I saw it this time either. Do you have a time before launch it was shown at?
(Blurry) screenshot here: http://forum.nasaspaceflight.com/index.php?topic=38149.msg1465044.msg#1465044

It was during the factory tour, and if I recall correctly it was a FH octoweb.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH on 02/18/2016 08:34 am
My guess is that there's a little unnecessary drama going on in this thread.

Indeed. Rockets get delayed all the time. Because they are complicated devices that need to be well engineered, and that takes time.

So SpaceX lost a launch. It's a shame. It's also not the end of SpaceX. Or the F9H.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 02/18/2016 08:43 am
While I'm sure there's been technical issues with the Falcon Heavy, that's not what has delayed it. They're waiting for the politics with the military launches to become predictable. Why? Because that's what Falcon Heavy is for.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 02/18/2016 10:04 am
While I'm sure there's been technical issues with the Falcon Heavy, that's not what has delayed it. They're waiting for the politics with the military launches to become predictable. Why? Because that's what Falcon Heavy is for.

This. But IMO they wanted a consolidated type of core they will produce in larger numbers for a longer time without major changes. The present version will be that core I am confident. Had they built a 1.1 heavy they would now need to make major changes.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: woods170 on 02/18/2016 10:22 am
Over-promising and under-delivering has just cost Falcon Heavy a mission:

http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/

And Arianespace just lucked out in filling a hole in their manifest.

Didn't cost Spacex a mission. ViaSat is using the Falcon Heavy for the ViaSat-3 platform in 2019.
source:
http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html (http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html)

Are you assuming SpaceX wouldn't have won a contract for either of the ViaSat3 payloads after a successful ViaSat2 launch?  That's the only way you can say they didn't lose a mission.
They would have won both.
I suggest you refrain from presenting personal opinion as fact.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: FinalFrontier on 02/18/2016 11:16 am
Seems to me the issue is the iterative design process that SpaceX is so fond of, and even relies on at this point.

It is a double edged sword. On the one hand it is very easy for engineers to re-design, and constantly upgrade and optimize components and the entire vehicle and then go out onto the production floor and make the changes in real time. This is a big part of why SpaceX has been so successful to this point.

On the other hand, if your upcoming MLV/HLV relies on three first stages that are based around the design of another vehicle, and you continuously change the design of that vehicle, this in turn means you must continuously change, delay, re-model, re-test, so forth, the vehicle that is dependent on those cores. I think this is the crux of the problem. Falcon 9 has been changed so many times in the last 6 years it's not hard to see why Falcon Heavy has constantly been delayed year after year. I think the other problem is over-optimization. SpaceX seems to not want to fly Falcon Heavy until they have the "best possible optimized" version of Falcon 9 they can get. This is a paradox because you can never perfectly optimize, and you will end up constantly changing things and delaying yourself if you try to over optimize. Which in turn delays Falcon Heavy by at least an exponent every single time because "no wait, we need to optimize F9 more first wait another 6 months", ect.

There don't seem to be any great technical challenges, nor have there been, to building and flying Falcon Heavy as a vehicle, it would rely on concepts that have already been proven. The only issue seems to be over optimization and constantly trading getting the vehicle online for this.

My two cents here.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dror on 02/18/2016 11:24 am
Over-promising and under-delivering has just cost Falcon Heavy a mission:

http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/

And Arianespace just lucked out in filling a hole in their manifest.

Didn't cost Spacex a mission. ViaSat is using the Falcon Heavy for the ViaSat-3 platform in 2019.
source:
http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html (http://www.prnewswire.com/news-releases/viasat-announces-third-quarter-fiscal-year-2016-results-300217686.html)

Are you assuming SpaceX wouldn't have won a contract for either of the ViaSat3 payloads after a successful ViaSat2 launch?  That's the only way you can say they didn't lose a mission.
They would have won both.
I suggest you refrain from presenting personal opinion as fact.
Point taken.
Though I was trying to suggest a possible answer to gongora's question, not my personal opinion.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: matthewkantar on 02/18/2016 12:12 pm
Seems to me the issue is the iterative design process that SpaceX is so fond of, and even relies on at this point.

It is a double edged sword. On the one hand it is very easy for engineers to re-design, and constantly upgrade and optimize components and the entire vehicle and then go out onto the production floor and make the changes in real time. This is a big part of why SpaceX has been so successful to this point.

There don't seem to be any great technical challenges, nor have there been, to building and flying Falcon Heavy as a vehicle, it would rely on concepts that have already been proven. The only issue seems to be over optimization and constantly trading getting the vehicle online for this.

My two cents here.

SaceX could have launched a heavy long ago. I suspect Musk is extremely reluctant to fly one before he is nearly certain he won't be throwing away three cores.

Matthew
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jcc on 02/18/2016 12:38 pm
Wanting to be able to recover cores is a big thing, but also the fact that FH will have a low lanch rate means after the first test,  they might launch one or two paid missions before a major revision to the core happens again, perhaps requiring they do a deeply discounted launch for a customer willing to take a risk.

At this point they have a few FH launches manifested, and also they are unlikely to make a major revision to the F9 core for the next few years.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH on 02/18/2016 12:57 pm
Seems to me the issue is the iterative design process that SpaceX is so fond of, and even relies on at this point.

It is a double edged sword. On the one hand it is very easy for engineers to re-design, and constantly upgrade and optimize components and the entire vehicle and then go out onto the production floor and make the changes in real time. This is a big part of why SpaceX has been so successful to this point.

On the other hand, if your upcoming MLV/HLV relies on three first stages that are based around the design of another vehicle, and you continuously change the design of that vehicle, this in turn means you must continuously change, delay, re-model, re-test, so forth, the vehicle that is dependent on those cores. I think this is the crux of the problem. Falcon 9 has been changed so many times in the last 6 years it's not hard to see why Falcon Heavy has constantly been delayed year after year. I think the other problem is over-optimization. SpaceX seems to not want to fly Falcon Heavy until they have the "best possible optimized" version of Falcon 9 they can get. This is a paradox because you can never perfectly optimize, and you will end up constantly changing things and delaying yourself if you try to over optimize. Which in turn delays Falcon Heavy by at least an exponent every single time because "no wait, we need to optimize F9 more first wait another 6 months", ect.

There don't seem to be any great technical challenges, nor have there been, to building and flying Falcon Heavy as a vehicle, it would rely on concepts that have already been proven. The only issue seems to be over optimization and constantly trading getting the vehicle online for this.

My two cents here.

Whilst the iterative approach does have disadvantages, I don't think they come in to play here. I suspect that had SpaceX gone for a different design approach, the F9H would be even further away than it is now, and would probably be a 5 year old design with no reusability, and small(er) payload.

As it is, it will be a modern design with some good proportion of reusability and a very impressive payload performance.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: fvandrog on 02/18/2016 01:08 pm
The loss of this payload for FH is interesting in a very bad way for SpaceX.   

I'd actually argue that in the long term it is much worse for Ariane Space -- they risk becoming compliant instead of pushing the development of their new launcher.

And whatever one can criticize about SpaceX, compliancy isn't the problem for them.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 02/18/2016 01:19 pm
SpaceX has been clear from the start that FH development was a lower priority than F9 work.  As such they have been quite consistent in delaying it whenever there was more-important F9 work to do (F9 1.1, F9 FT, RTF, recovery, etc).  I don't know why that's so hard for folks to understand.  Prioritizing the money-generating business is how SpaceX sticks around, and is sound management process.

The alternative would be to blow a huge amount of money and manufacturing resources on a dedicated FH team... and then where do you put your best engineers?  On FH, neglecting F9? Or on F9, jeopardizing FH?  SpaceX believes it already has hired the best folks, and it has asked them to work on FH as a second-tier project behind F9.

That seems entirely straight-forward and reasonable to me.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: woods170 on 02/18/2016 01:34 pm
SpaceX has been clear from the start that FH development was a lower priority than F9 work.  As such they have been quite consistent in delaying it whenever there was more-important F9 work to do (F9 1.1, F9 FT, RTF, recovery, etc).  I don't know why that's so hard for folks to understand.  Prioritizing the money-generating business is how SpaceX sticks around, and is sound management process.

The alternative would be to blow a huge amount of money and manufacturing resources on a dedicated FH team... and then where do you put your best engineers?  On FH, neglecting F9? Or on F9, jeopardizing FH?  SpaceX believes it already has hired the best folks, and it has asked them to work on FH as a second-tier project behind F9.

That seems entirely straight-foreward and reasonable to me.
Indeed it is. Too bad that some folks keep referring to the "2013" date originally issued by Elon. The time-dilutation factor on major SpaceX programs has consistenly been 4 years for the past decade. So, FH will eventually fly, and that first flight will be next year.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GWH on 02/18/2016 01:50 pm
Falcon heavy isn't particularly competitive with ariane 5 for single 7 tonne payloads unless it uses dual manifest OR reuse.
Without reuse it's an over capable rocket.

Makes sense for them to have waited.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: roparker on 02/18/2016 02:35 pm
The loss of this payload for FH is interesting in a very bad way for SpaceX.   

I'd actually argue that in the long term it is much worse for Ariane Space -- they risk becoming compliant instead of pushing the development of their new launcher.

And whatever one can criticize about SpaceX, compliancy isn't the problem for them.

I assume you meant complacent and complacency not compliant and compliancy.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 02/18/2016 04:14 pm
The FH will take up 2 months of core manufacturing capability and testing. At the moment they seem to be barley ahead of F9 launch schedule. SpaceX took a big hit to their core manufacturing schedules when they had to go back and modify existing almost finished and finished FT cores. Once the almost finished cores have been modified and the design changes become the normal production instead of a retrofit, the production rates should improve significantly.

By evidence of the FH moving to Aug-Sep that clearing of retrofitted cores will occur this spring with production ramping up enough to be able meet the F9 launch schedule as well as being able to build three extra cores to do the first FH launch.

On another note the FH is a Supper Heavy by way of NASA classification since it is capable of >50mt to LEO. But it will mainly operate as only a Heavy 20mt> FH <50mt. By the same the F9 is actually capable of >20mt (with no margins and fully expendable) so it is a HLV as well but will operate as only a Medium.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 02/18/2016 04:41 pm
SpaceX has been clear from the start that FH development was a lower priority than F9 work.  As such they have been quite consistent in delaying it whenever there was more-important F9 work to do (F9 1.1, F9 FT, RTF, recovery, etc).  I don't know why that's so hard for folks to understand.  Prioritizing the money-generating business is how SpaceX sticks around, and is sound management process.

The alternative would be to blow a huge amount of money and manufacturing resources on a dedicated FH team... and then where do you put your best engineers?  On FH, neglecting F9? Or on F9, jeopardizing FH?  SpaceX believes it already has hired the best folks, and it has asked them to work on FH as a second-tier project behind F9.

That seems entirely straight-foreward and reasonable to me.

Is it a valid corallary then that low priority projects would potentially be cancellled as other more interesting & profitable pieces of business come along?   CRS-2 , Dragonfly,upper stage raptor, etc.?   I think SpaceX will analyze and act on these motives like any other company.   
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 02/18/2016 05:27 pm
Falcon heavy isn't particularly competitive with ariane 5 for single 7 tonne payloads unless it uses dual manifest OR reuse.
Without reuse it's an over capable rocket.

Makes sense for them to have waited.
Well, the Euro-USD has sort of made Ariane 5 a lot more competitive. If I'm not mistaken, a whole Ariane 5 costs about USD 200M. But the lower berth uses only 35% of the payload mass. And it has to compete with Falcon 9 (and technically Sea Launch, Proton-M, Atlas V, H-IIA). So they can't really charge more than 65M to 70M. That means that the top berth should be around 130M to 135M. I would say that SpaceX can price the FH quite lower than that. And they have to until they prove FH reliability.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sdsds on 02/18/2016 07:19 pm
I'm getting anxious now.  Gwynne Shotwell said we'd get a performance update on Falcon Heavy early this week...  It's hard to be patient!

If you were anxious a week ago I'm curious. How are you feeling about it now, 7 days later?

;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: FinalFrontier on 02/18/2016 08:40 pm
Seems to me the issue is the iterative design process that SpaceX is so fond of, and even relies on at this point.

It is a double edged sword. On the one hand it is very easy for engineers to re-design, and constantly upgrade and optimize components and the entire vehicle and then go out onto the production floor and make the changes in real time. This is a big part of why SpaceX has been so successful to this point.

There don't seem to be any great technical challenges, nor have there been, to building and flying Falcon Heavy as a vehicle, it would rely on concepts that have already been proven. The only issue seems to be over optimization and constantly trading getting the vehicle online for this.

My two cents here.

SaceX could have launched a heavy long ago. I suspect Musk is extremely reluctant to fly one before he is nearly certain he won't be throwing away three cores.

Matthew
While I disagree they could have done it "long ago" (I don't think they had adequate amounts of flight proven hardware  earlier), I do agree that he may be risk averse as far as wasting the cores. Landing all three would be very difficult, and that's if the vehicle stages properly and actually works.

But sooner or later you have to fly the rocket and see if it works or not.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: FinalFrontier on 02/18/2016 09:00 pm
Falcon heavy isn't particularly competitive with ariane 5 for single 7 tonne payloads unless it uses dual manifest OR reuse.
Without reuse it's an over capable rocket.

Makes sense for them to have waited.
Or without BEO payloads.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/18/2016 09:17 pm
I sometimes think they are waiting on routine successful landings of F9, then either use used cores on the FH to begin with or have the ability to land all three cores.  They only have one landing pad at the cape.  Would they need at least one more plus the ocean landing?  Are they going to put a used core in the center and scrap it and save the two outer ones on the first few launches? 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 02/18/2016 10:03 pm
I sometimes think they are waiting on routine successful landings of F9, then either use used cores on the FH to begin with or have the ability to land all three cores.  They only have one landing pad at the cape.  Would they need at least one more plus the ocean landing?  Are they going to put a used core in the center and scrap it and save the two outer ones on the first few launches?

There is one landing area. I believe, however, it has five separate landing pads on it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RocketGoBoom on 02/18/2016 10:17 pm
I sometimes think they are waiting on routine successful landings of F9, then either use used cores on the FH to begin with or have the ability to land all three cores.  They only have one landing pad at the cape.  Would they need at least one more plus the ocean landing?  Are they going to put a used core in the center and scrap it and save the two outer ones on the first few launches?

There is one landing area. I believe, however, it has five separate landing pads on it.

If the two side cores were landing at the same time, or within seconds of each other, could that possibly cause an issue if these landing areas are in close proximity to each other? How far apart do these things need to be for safe clearance zone of the wake that each produces?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MrHollifield on 02/18/2016 10:42 pm
Are they going to put a used core in the center and scrap it and save the two outer ones on the first few launches? 
AIUI, the center core is not a standard F9-S1 because it has the extra attachments for the side boosters and a stronger S2 attachment, so they would not be able to have a used S1 as the center core. They may be waiting to have 2 flown side boosters so they don't have to fly new S1s on the test flight.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jcc on 02/18/2016 10:43 pm
I sometimes think they are waiting on routine successful landings of F9, then either use used cores on the FH to begin with or have the ability to land all three cores.  They only have one landing pad at the cape.  Would they need at least one more plus the ocean landing?  Are they going to put a used core in the center and scrap it and save the two outer ones on the first few launches?

There is one landing area. I believe, however, it has five separate landing pads on it.

If the two side cores were landing at the same time, or within seconds of each other, could that possibly cause an issue if these landing areas are in close proximity to each other? How far apart do these things need to be for safe clearance zone of the wake that each produces?

Given the high landing precision they have shown, they could probably land 50m away from each other without a problem. The greater concern might be mid-air collision, so they need to guarantee that the trajectories to the pad don't cross.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rpapo on 02/18/2016 10:46 pm
Given the high landing precision they have shown, they could probably land 50m away from each other without a problem. The greater concern might be mid-air collision, so they need to guarantee that the trajectories to the pad don't cross.
I would think it best to aim each booster so that the atmospheric entry interfaces are a mile or two apart, and then use the grid fins to converge on the precise landing spots.  By making sure that the northern booster reenters on the north, and the southern on the south, you should be able to avoid collisions.

Upper level winds may complicate matters, though.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: llanitedave on 02/18/2016 11:43 pm
The loss of this payload for FH is interesting in a very bad way for SpaceX.   

I'd actually argue that in the long term it is much worse for Ariane Space -- they risk becoming compliant instead of pushing the development of their new launcher.

And whatever one can criticize about SpaceX, compliancy isn't the problem for them.

I assume you meant complacent and complacency not compliant and compliancy.


That would definitely reduce my confusion!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: llanitedave on 02/18/2016 11:48 pm
SpaceX has been clear from the start that FH development was a lower priority than F9 work.  As such they have been quite consistent in delaying it whenever there was more-important F9 work to do (F9 1.1, F9 FT, RTF, recovery, etc).  I don't know why that's so hard for folks to understand.  Prioritizing the money-generating business is how SpaceX sticks around, and is sound management process.

The alternative would be to blow a huge amount of money and manufacturing resources on a dedicated FH team... and then where do you put your best engineers?  On FH, neglecting F9? Or on F9, jeopardizing FH?  SpaceX believes it already has hired the best folks, and it has asked them to work on FH as a second-tier project behind F9.

That seems entirely straight-foreward and reasonable to me.

Is it a valid corallary then that low priority projects would potentially be cancellled as other more interesting & profitable pieces of business come along?   CRS-2 , Dragonfly,upper stage raptor, etc.?   I think SpaceX will analyze and act on these motives like any other company.


Not in this case.  Instead of "low priority" think of "low urgency".  I hate to fall back on my old Steven Covey, but classifying goals as to urgency and importance independently helps you schedule your work better.  Concentrate first on that which is urgent and important, next on which is important but not urgent, last on what is urgent but not important, and if it's neither urgent nor important, just drop it.  Falcon heavy has always been important, but its been less urgent than getting F9 fully operational.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: launchwatcher on 02/19/2016 12:52 am
Given the high landing precision they have shown, they could probably land 50m away from each other without a problem. The greater concern might be mid-air collision, so they need to guarantee that the trajectories to the pad don't cross.
Fragmentation distance is another thing to worry about.   The CRS-6 landing video ends before all the fragments splash down but shows splashes in the water on the right side maybe 1.5 to 2 times the width of the barge from the touchdown point, and larger chunks flying left.

I don't think you want a nearby missed landing to doom a successfully landed stage.


Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/19/2016 03:15 am
While I'm sure there's been technical issues with the Falcon Heavy, that's not what has delayed it. They're waiting for the politics with the military launches to become predictable. Why? Because that's what Falcon Heavy is for.
Theyre not waiting on politics. That's absurd. No reason to wait. Launch now and you have a much bigger bargaining chip.

I think it's about Falcon 9 maturing, and a long manifest that keeps getting longer. And a bunch of other projects like Dragon 2, reuse, etc, that they're just as behind on (though making real progress).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 02/19/2016 03:17 am
Theyre not waiting on politics. That's absurd. No reason to wait. Launch now and you have a much bigger bargaining chip.

You'll have an uncertified vehicle with a giant sunk cost.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/19/2016 03:31 am
Theyre not waiting on politics. That's absurd. No reason to wait. Launch now and you have a much bigger bargaining chip.

You'll have an uncertified vehicle with a giant sunk cost.
And they already have that. Not flying will delay certification further, and the sunk cost they've already put into it will accumulate.

And they have multiple commercial customers signed up for it, and they lost one extra bird (slipped from Viasat2 to 3, could've been both) due to delay.

There's nothing to be gained by waiting it out.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 02/19/2016 03:40 am
And they have multiple commercial customers signed up for it, and they lost one extra bird (slipped from Viasat2 to 3, could've been both) due to delay.

It's not worth doing it for the commercial customers alone.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 02/19/2016 04:08 am
And they have multiple commercial customers signed up for it, and they lost one extra bird (slipped from Viasat2 to 3, could've been both) due to delay.

It's not worth doing it for the commercial customers alone.

What do you mean by word "if"?

Development of FH from scratch would not be worth doing it for commercial customers alone.

But they have already done almost all of the development work. What is left is really, really small part.

And, as somebody else already said: The earlier they fly, the earlier they get the air force certification.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 02/19/2016 04:16 am
And, as somebody else already said: The earlier they fly, the earlier they get the air force certification.

No.. the earlier they fly, the earlier they produce the wrong vehicle to get air force certification, get shuffled from office to office, sue, get forced into arbitration, hire the services of three more senators and generally just shovel money into the fire.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dorkmo on 02/19/2016 04:19 am
seems like most of the costs that are going to sink have already sunk, but on the plus side they can have the pad and everything ready for whatever gets certified?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 02/19/2016 05:48 am
And, as somebody else already said: The earlier they fly, the earlier they get the air force certification.

No.. the earlier they fly, the earlier they produce the wrong vehicle to get air force certification, get shuffled from office to office, sue, get forced into arbitration, hire the services of three more senators and generally just shovel money into the fire.

Yes, that is how it will roll.  Whatever the sunk costs actually are, ( how expensive are YouTube videos & upgraded TEL's,  anyways?)  it will pale in comparison to the costs once they commit to the first two "test" flights and maintaining capability for the wrong vehicle to be ready to launch very  infrequent payloads.   

With no commercial market materializing for FH, the Air Force pretty much looks to be the whole game for FH.  Given the low numbers of payloads suitable for FH from government sources, that game doesn't look so good.   It sometimes makes me wonder if keeping FH alive is the price SpaceX pays to be in good graces for F9-FT.  Play the AF game for the big rocket they will maybe want someday, maybe... 2 or 3 times a decade...maybe...?

FH may have seemed like a great idea long ago ( 3-4 years per SpaceX time dilation standards) but it is not a "gate" they need to pass through for their Mars plans, and commercially it is never going to be anything but the tail end of their revenue stream & a distraction from executing their prime need to increase flight rate of F9-FT.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dror on 02/19/2016 06:06 am

Not in this case.  Instead of "low priority" think of "low urgency".  I hate to fall back on my old Steven Covey, but classifying goals as to urgency and importance independently helps you schedule your work better.  Concentrate first on that which is urgent and important, next on which is important but not urgent, last on what is urgent but not important, and if it's neither urgent nor important, just drop it.  Falcon heavy has always been important, but its been less urgent than getting F9 fully operational.
If SpaceX are on a path that will lead them to a Raptor 2nd stage mid term and to BFR long term, then FH may be neither urgent nor importent.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 02/19/2016 07:19 am
Unless they want Falcon Heavy's 13+ tonne mass to Mars for pre-BFR Mars precursor missions and/or mass deployments of their comms constellation. Then they're they're at least partly their own customer.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: raketa on 02/19/2016 03:57 pm
Given the high landing precision they have shown, they could probably land 50m away from each other without a problem. The greater concern might be mid-air collision, so they need to guarantee that the trajectories to the pad don't cross.
I would think it best to aim each booster so that the atmospheric entry interfaces are a mile or two apart, and then use the grid fins to converge on the precise landing spots.  By making sure that the northern booster reenters on the north, and the southern on the south, you should be able to avoid collisions.

Upper level winds may complicate matters, though.
I think by slightly difference in timing of braking burn, they could separate stages horizontally and avoid collision by landing in slightly different time.I think separation in order 10-20 second will be good enough.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: parham55 on 02/19/2016 04:21 pm
I think by slightly difference in timing of braking burn, they could separate stages horizontally and avoid collision by landing in slightly different time.I think separation in order 10-20 second will be good enough.

Which braking burn? The boostback, re-entry or landing braking burn? I would guess you mean the boostback burn and I would suspect you are correct.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/19/2016 04:53 pm
If they get the methane Raptor second stage, this greatly increases the payloads F9 FT can deliver and it will cut into FH's potential launches also.  On the other hand, with a Raptor upper stage on the FH, it will greatly increase it's capabilities and maybe open doors to payloads that SLS would have launched. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 02/19/2016 07:11 pm
If they get the methane Raptor second stage, this greatly increases the payloads F9 FT can deliver and it will cut into FH's potential launches also.  On the other hand, with a Raptor upper stage on the FH, it will greatly increase it's capabilities and maybe open doors to payloads that SLS would have launched.

A raptor second stage is only an incremental improvement for F9/FH, if any payload improvement at all, because of the likely reuse penalty.  Little will change in the F9/FH balance IMO; biggest impact will probably be the extension of FH capability into the SLS Block 1 range.

The impact comes when it is reusable and refuelable... everything from routine tanker flights to higher energy/mass interplanetary launches become possible.

A refuelable upper stage will out-perform any SLS Block 1/2 on TLI or TMI.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sewebster on 02/19/2016 07:46 pm
People have pointed out reasons why SpaceX might want to delay FH... and I agree that I don't think losing the one ViaSat launch is a huge deal... but presumably there is a bigger picture for ALL of the commercial clients signed up for FH... if SpaceX keeps pushing the schedule. I mean, are they actually on a schedule to launch (even if there are minor delays?) Or are they still thinking about it? Seems like a big difference to a customer.

But maybe all the customers have been briefed on all this and are "on board" with the situation...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/19/2016 08:41 pm
If they get a Raptor upper stage engine developed, it would not be long before a first stage engine could be developed.   Then they could go straight to BFR or a mini-BFR.  Things change all the time. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: 3Davideo on 02/19/2016 08:46 pm
Personal opinion: Once FH is up and running, it's possible that there will be more satellites built that can only be launched on the FH (except maybe, and possibly including the more expensive Delta IV Heavy).  So even if F9 FT and further upgrades erode the market base on the low side, I still think they'll see growth on the high side. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 02/19/2016 09:49 pm
Personal opinion: Once FH is up and running, it's possible that there will be more satellites built that can only be launched on the FH

Not really, because the satellite operators don't want to be tied to one vehicle.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/19/2016 09:51 pm
Personal opinion: Once FH is up and running, it's possible that there will be more satellites built that can only be launched on the FH

Not really, because the satellite operators don't want to be tied to one vehicle.
This is true, and will give ULA motivation to make Vulcan Heavy (as soon in a ULA graphic) a more real capability.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 02/19/2016 09:54 pm
Personal opinion: Once FH is up and running, it's possible that there will be more satellites built that can only be launched on the FH

Not really, because the satellite operators don't want to be tied to one vehicle.

They have Ariane. Somewhat expensive if it is only one big sat but it is an alternative.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 02/19/2016 10:55 pm
Great, terminology aside, the fact remains that you should treat all rockets that haven't flown with some scepticism.

Sure, skepticism is valid.  Just because someone builds something doesn't mean it will meet it's intended goals.

However with regards to the Falcon Heavy, a binary set of choices (i.e. it's either a paper rocket or it's a real rocket) doesn't make sense.

For instance, SpaceX now has substantially more resources than it did when it was getting to launch the Falcon 1, and it has proven that it can design, build and launch the Falcon 9 with pretty good reliability.

And since the Falcon Heavy is using a proven method of combining three cores, there are far fewer questions about the likelihood of them being able to eventually build and launch the Falcon Heavy successfully.  Maybe that won't be on the first launch, but they have the financial and engineering resources to fine tune towards success.

So is Falcon Heavy a "paper rocket"?  No.  Is it a proven one?  No.  Is it an iteration of a proven design?  Yes.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Ronsmytheiii on 02/20/2016 01:01 pm
Falcon heavy isn't particularly competitive with ariane 5 for single 7 tonne payloads unless it uses dual manifest OR reuse.
Without reuse it's an over capable rocket.

Makes sense for them to have waited.

I will agree that they waited for reusability, but for different reasons. At the end of the EELV design process, both Lockheed and Boeing decided to add SRB capabilities for more payload flexibility without resorting to tri-core heavies in response to the commercial market's demands.  SpaceX does not have that flexibility, so a Heavy must compete with single core LV's for heavier (not the heaviest though) payloads.  Without reuse, the Falcon Heavy could be too expensive for payloads slightly too heavy for Falcon 9.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 02/20/2016 01:20 pm
Falcon Heavy could launch multiple payloads that might be too heavy for one Falcon 9.   Maybe one large one and two or three lighter ones. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 02/20/2016 03:01 pm
I will agree that they waited for reusability, but for different reasons.

I'm in the camp of people that thinks that Falcon Heavy was delayed due to a lack of resources - that it was not a priority, did not have pressing customer launch needs, and their company resources were needed elsewhere (i.e. v1.1 FT, Dragon Crew, etc.).

Quote
At the end of the EELV design process, both Lockheed and Boeing decided to add SRB capabilities for more payload flexibility without resorting to tri-core heavies in response to the commercial market's demands.  SpaceX does not have that flexibility, so a Heavy must compete with single core LV's for heavier (not the heaviest though) payloads.  Without reuse, the Falcon Heavy could be too expensive for payloads slightly too heavy for Falcon 9.

Musk doesn't need to win every launch order in order to achieve a large backlog of launch orders.  No doubt there is an "80/20 rule" that applies here, and SpaceX is better off just focusing on the broad middle part of the market.

Plus, if they perfect reusability, they will be changing the market.  And that changed market will focus on the abilities SpaceX offers for reusability and lower launch costs, so SpaceX won't have to worry about odd sized payloads - they want quantity.

My $0.02
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 02/20/2016 05:05 pm

At the end of the EELV design process, both Lockheed and Boeing decided to add SRB capabilities for more payload flexibility without resorting to tri-core heavies in response to the commercial market's demands.  SpaceX does not have that flexibility, so a Heavy must compete with single core LV's for heavier (not the heaviest though) payloads.  Without reuse, the Falcon Heavy could be too expensive for payloads slightly too heavy for Falcon 9.

Musk doesn't need to win every launch order in order to achieve a large backlog of launch orders.  No doubt there is an "80/20 rule" that applies here, and SpaceX is better off just focusing on the broad middle part of the market.

Plus, if they perfect reusability, they will be changing the market.  And that changed market will focus on the abilities SpaceX offers for reusability and lower launch costs, so SpaceX won't have to worry about odd sized payloads - they want quantity.

My $0.02

These are interesting points.   In regards to LM & Boeing adding SRB's to their EELV designs, F9-FT needs the equivalent impulse of around 2 GEM-60's to deliver 6.5-7.0 ton comsats to GTO.  Add a 3rd or 4th SRB and there would be margins for recovery of the core.   It is sobering to think that 2 little SRB's using 60,000kg of propellant would give the needed performance that is being provided by the two FH side cores with some 870,000 kg propellant.  That seems a steep price in complexity to get the marginal improvement for the larger comsats.  It makes sense for multiple payload or very large payloads, but is very questionable for launching the 6.5-7.0 ton payloads, even with reuse.

A F9 vehicle configured with smaller boosters, or small Raptor upper stage could cover the remaining 20% of the commercial market. ( & probably more than 20% of the available revenue).   It doesn't cover the heaviest of the possible government payloads.   As far as dual payloads justifying the FH, Ariane is backing away from that losing strategy.  Why?

As skeptical as I am FH, I do wish it success in changing the demand side of the launch market.  I do question how long that will take.   If it happens quickly, FH may have a future.  If it takes upwards of a decade, I don't see how it makes any sense not to scrap FH and adapt another design.   Evolving F9-FT to be adaptable to smaller boosters is the quickest path, & seems well within the capability of SpaceX's engineering talent.   A high energy upper stage would take longer, but could obsolete the smaller boosters when it becomes available.   It does seem worth the effort to be competitive in the full comsat market, and not leave that top value revenue to competitors. 


Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: punder on 02/20/2016 05:28 pm
It is sobering to think that 2 little SRB's using 60,000kg of propellant would give the needed performance that is being provided by the two FH side cores with some 870,000 kg propellant.

It's likely SpaceX has mulled the costs and benefits of using solids, but doubtful they will ever adopt them. These are some possible downsides:

1. Musk has made the point many times that propellant is cheap in relation to expendable hardware.
2. Adding solids goes against his philosophy of reuse for drastic cost reduction.
3. It would require serious analysis and redesign of the entire rocket and its trajectory, not just the first stage.
4. It would involve contracting with outside providers who would, in their old-school way, charge exorbitant prices for the strap-ons and impose a set of SpaceX-uncontrollable schedule constraints--one of the primary reasons Musk started SpaceX in the first place and brought as much manufacturing as possible in-house.
5. It would mean integrating another huge set of storage, handling and launch procedures that are foreign to the SpaceX way of doing things.
6. It would mean more lengthy and expensive rounds with the EPA.
7. It would destroy (perhaps literally) the concept of survivable engine-out during first stage burn.
8. It would look like a defeat--a concession to the competitors.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 02/20/2016 05:33 pm
To be very clear, I was not suggesting that SpaceX use SRB's.  I brought it up as illustrative of the inefficiency & overkill of the FH configuration for the single launch to GTO, large comsat ( 6.5-7.0 ton range).   As a skeptic of FH, I'm at least trying to suggest alternate paths.

I discussed my specific thoughts back on pg. 10-11 in this thread, and was met with the enthusiasm of a leper or heretic.  But that's OK!  I think FH is a very interesting & troubled vehicle, very worth of discussion pro & con.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/20/2016 06:19 pm
Falcon Heavy gets like 20 tons to LEO GTO expendable. A couple of SRBs doesn't do that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 02/20/2016 09:34 pm
In regards to LM & Boeing adding SRB's to their EELV designs, F9-FT needs the equivalent impulse of around 2 GEM-60's to deliver 6.5-7.0 ton comsats to GTO.  Add a 3rd or 4th SRB and there would be margins for recovery of the core.   It is sobering to think that 2 little SRB's using 60,000kg of propellant would give the needed performance that is being provided by the two FH side cores with some 870,000 kg propellant.  That seems a steep price in complexity to get the marginal improvement for the larger comsats.  It makes sense for multiple payload or very large payloads, but is very questionable for launching the 6.5-7.0 ton payloads, even with reuse.

To be very clear, I was not suggesting that SpaceX use SRB's.  I brought it up as illustrative of the inefficiency & overkill of the FH configuration for the single launch to GTO, large comsat ( 6.5-7.0 ton range).   As a skeptic of FH, I'm at least trying to suggest alternate paths.... I think FH is a very interesting & troubled vehicle, very worth of discussion pro & con.

This is like saying you don't need a semi to move, as you can get all your stuff in 1 U-Haul truck plus two pickup trucks, even though the pickup trucks have to be thrown away after one use. Even if the semi has excess capacity and uses more fuel, it is still far more economical to burn more fuel and not throw away any of the hardware.

I would agree that expending one liquid core and a few small solids is cheaper than expending three liquid cores. Once the liquids are recoverable and reusable, however, the choice is between the cost of extra liquid prop or the cost of disposable solids (which do come with some cons). IMHO, just burning more prop seems to have the advantage. Then there is the fact that the reusable tri-core can do that job as well as much more. You have one infrastructure for all possible payloads. Add solids and you have to introduce other complexities.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 02/20/2016 10:40 pm
Falcon Heavy gets like 20 tons to LEO GTO expendable. A couple of SRBs doesn't do that.

That is true, but using FH in expendable mode for +6.5 ton comsats is what I was suggesting as overkill.   What can FH do to GTO when all cores are RTLS?  Or when the center core is DPL?   The reuse scenarios are the subject that is accurate to weigh alternate FH options against.

The SES-9 mission is interesting to the FH discussion, as it will inform a pretty good estimate of the max payload of F9-FT to GTO.   What then is the best solution to cover the gap between F9-FT to the lager and lucrative GTO payloads?   FH is the current SpaceX solution to that market.  It does not appear to be doing well.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 02/20/2016 11:10 pm

This is like saying you don't need a semi to move, as you can get all your stuff in 1 U-Haul truck plus two pickup trucks, even though the pickup trucks have to be thrown away after one use. Even if the semi has excess capacity and uses more fuel, it is still far more economical to burn more fuel and not throw away any of the hardware.

I would agree that expending one liquid core and a few small solids is cheaper than expending three liquid cores. Once the liquids are recoverable and reusable, however, the choice is between the cost of extra liquid prop or the cost of disposable solids (which do come with some cons). IMHO, just burning more prop seems to have the advantage. Then there is the fact that the reusable tri-core can do that job as well as much more. You have one infrastructure for all possible payloads. Add solids and you have to introduce other complexities.

Again, the SRB's were just used as an illustration of the overkill of the tri-core FH.  The point was that the extra impulse they would give to a F9-FT core would be enough for getting 6.5-7.0 tons to GTO with extra margin for DPL.   

I would re-write your analogy like this:  F9-FT is like a Ford F-250 with a 4000lb load capacity.  FH ( in full reuse mode) is like bolting three F-250's together when the task is to carry a 5000 lb load.  What if a way could be found to carry that marginal 1000 lbs by bolting on two Ford Focus's to the F-250?
 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 02/20/2016 11:24 pm
In regards to LM & Boeing adding SRB's to their EELV designs, F9-FT needs the equivalent impulse of around 2 GEM-60's to deliver 6.5-7.0 ton comsats to GTO.  Add a 3rd or 4th SRB and there would be margins for recovery of the core.   It is sobering to think that 2 little SRB's using 60,000kg of propellant would give the needed performance that is being provided by the two FH side cores with some 870,000 kg propellant.  That seems a steep price in complexity to get the marginal improvement for the larger comsats.  It makes sense for multiple payload or very large payloads, but is very questionable for launching the 6.5-7.0 ton payloads, even with reuse.

To be very clear, I was not suggesting that SpaceX use SRB's.  I brought it up as illustrative of the inefficiency & overkill of the FH configuration for the single launch to GTO, large comsat ( 6.5-7.0 ton range).   As a skeptic of FH, I'm at least trying to suggest alternate paths.... I think FH is a very interesting & troubled vehicle, very worth of discussion pro & con.

This is like saying you don't need a semi to move, as you can get all your stuff in 1 U-Haul truck plus two pickup trucks, even though the pickup trucks have to be thrown away after one use. Even if the semi has excess capacity and uses more fuel, it is still far more economical to burn more fuel and not throw away any of the hardware.

I would agree that expending one liquid core and a few small solids is cheaper than expending three liquid cores. Once the liquids are recoverable and reusable, however, the choice is between the cost of extra liquid prop or the cost of disposable solids (which do come with some cons). IMHO, just burning more prop seems to have the advantage. Then there is the fact that the reusable tri-core can do that job as well as much more. You have one infrastructure for all possible payloads. Add solids and you have to introduce other complexities.
You talk like integrating, testing, handling, launching, recovering and inspecting three cores came at the same cost as doing it for only one. Which it doesn't . It's about more than just fuel, no matter what Elon tweets.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 02/20/2016 11:39 pm
You talk like integrating, testing, handling, launching, recovering and inspecting three cores came at the same cost as doing it for only one. Which it doesn't . It's about more than just fuel, no matter what Elon tweets.

Today, sure.  But Musks goal is to mirror the reusable transportation systems we rely on today, in the air, on the ground, and in the water.

Their launch ops are already pretty speedy, and they have designed the Merlin engines to be reusable for many flights.  The question is whether they have achieved their intended results with their designs, but we really won't know until they get a whole lot more flights under their belt.

But if things prove out the way that they have designed them, the returned cores won't need testing and inspection, just like you don't test or inspect your car when you rely upon it to get you to work every day.

We're talking about a big paradigm shift here... assuming things work out the way they think they can.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 02/20/2016 11:44 pm
Let's wait and see how it turns out.
I don't see "no inspections". Also a Heavy will always need an ASDS and land landings to get all cores back, then there is the question on what the long-term success rate of recoveries will look like (for example you can't always expect to have reasonable weather for ASDS landings).
A lot of ifs to fill the time until they have a Raptor upper stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 02/20/2016 11:48 pm
Talking alternate scenarios and criticisms is fascinating, but as far as the actual FH configuration goes, I have read and seen some conflicting info regarding the differences of the center vs. side cores. I have read it here that all three cores are exact copies, with the exception that the center core has a mod kit for attaching side cores, and I have read elsewhere that the center core is slightly longer than the side cores and carries more S1 prop.

So any reasoning or confirmation either way?
1.  Should the center core be slightly longer than the side cores for extra fuel load & burn time in the S1?   
2.  By connecting the three cores together, does this constrain the vehicles bending moments & resonant modes so that the slenderness ratio that is limiting of F9-FT allows for a longer FH center core?

I am thinking it makes sense that the FH center core can be extended to the point that optimizes for burn time in excess of the side cores, yet still has to remain road transportable.  Bending forces and resonance for the center core is of less concern as by the time the side cores eject, the vehicle is past maxQ and aero forces are diminishing fast.

How these trades play out should determine the maximum size and mass that S2 can have, and what the ultimate potential of the FH could be.

 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sdsds on 02/20/2016 11:48 pm
We're talking about a big paradigm shift here... assuming things work out the way they think they can.

Yes, and Musk is of course "leaning forward" (and certainly not looking back!) when it comes to FH. But I just want to mention that if he's competing with DIV-H, he needs to consider the entire "National Mission Model" on which EELV was predicated, to the extant that those requirements from the past still apply today and will continue to apply in the future.

I forget whether it was "Mission C" or "Mission D", but one of them is GEO (not GTO) and requires just about every kilogram DIV-H with RS-68A can currently deliver....

http://fas.org/spp/military/program/launch/nmm.htm
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/20/2016 11:54 pm
Falcon Heavy gets like 20 tons to LEO GTO expendable. A couple of SRBs doesn't do that.

That is true, but using FH in expendable mode for +6.5 ton comsats is what I was suggesting as overkill.   What can FH do to GTO when all cores are RTLS?  Or when the center core is DPL?   The reuse scenarios are the subject that is accurate to weigh alternate FH options against.

The SES-9 mission is interesting to the FH discussion, as it will inform a pretty good estimate of the max payload of F9-FT to GTO.   What then is the best solution to cover the gap between F9-FT to the lager and lucrative GTO payloads?   FH is the current SpaceX solution to that market.  It does not appear to be doing well.
Considering how high performance the SES9 mission is, it seems quite reasonable that 6.5+ ton satellites would have all cores recovered, and probably all return to launch site even.

With Raptor, Falcon Heavy may be able to put the biggest commsats through GTO while being FULLY reused.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 02/20/2016 11:57 pm
That seems a steep price in complexity to get the marginal improvement for the larger comsats.  It makes sense for multiple payload or very large payloads, but is very questionable for launching the 6.5-7.0 ton payloads, even with reuse.

Remember SpaceX will be releasing new capability numbers for Falcon Heavy, so we'll have to wait to debate exact numbers until that happens.

Quote
As skeptical as I am FH, I do wish it success in changing the demand side of the launch market.  I do question how long that will take.   If it happens quickly, FH may have a future.  If it takes upwards of a decade, I don't see how it makes any sense not to scrap FH and adapt another design.

I don't think you really appreciate the elegance and efficiency of what SpaceX has done with the Falcon 9 and the Falcon Heavy.  Once the infrastructure is built (and it is), Falcon Heavy is practically free to maintain as a product/service - it's just standard Falcon 9 hardware.

Also you don't seem to appreciate how only having one real configuration (i.e. Falcon 9) being flown in two configurations (i.e. single core or triple core) gives them access to a great majority of the potential launch market - maybe all of it once they announce the new Falcon Heavy numbers.  Everything else is an expensive edge case that isn't worth going after.

So with the low pricing SpaceX offers for two standard launch configurations, SpaceX can get the market to adjust to them, instead of vice versa.

Quote
Evolving F9-FT to be adaptable to smaller boosters is the quickest path...

...the quickest path to complexity, and away from low cost.

Musk's goal is to lower the cost to access space, and that can't be done when you keep coming up with custom configurations of your standard product.

Plus, remember the market is never going to give SpaceX anywhere close to a majority of the total launch demand, so for SpaceX their best bet is to just go after what they can easily satisfy - that keeps prices low, which is what their competitive advantage is.  Custom configurations raise prices.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 02/21/2016 12:06 am
Let's wait and see how it turns out.
I don't see "no inspections".

Last time I flew on a commercial airliner I saw the pilot walking around the aircraft doing a visual inspection.  So light inspections happen all the time in the commercial world, but what I was meaning was Musk's goal is more along the lines of an external inspection and maybe a review of their sensor data, and if everything checks then it keeps moving back to the launch site for the next flight.

Quote
Also a Heavy will always need an ASDS and land landings to get all cores back, then there is the question on what the long-term success rate of recoveries will look like (for example you can't always expect to have reasonable weather for ASDS landings).

The goal is 100% reusable 1st stages, but obviously it will take a while to get there.  Don't rule out their customers making changes in order to take advantage of the lower pricing with recoverable stage flights.

Quote
A lot of ifs to fill the time until they have a Raptor upper stage.

At this point it's not confirmed that a Raptor upper stage will happen, so I only focus on what they have announced.  And they can do a lot of recovery with what they have announced.

But this whole process will be iterative, both with SpaceX and with their customers, and it will play out over years, not months.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 02/21/2016 02:07 am
Three words: "Mars precursor missions", as in before BFR. For these SpaceX R&D is the customer, unless NASA decides to tag along for a cheap secondary payload ride.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sdsds on 02/21/2016 02:20 am
Three words: "Mars precursor missions", as in before BFR. For these SpaceX R&D is the customer, unless NASA decides to tag along for a cheap secondary payload ride.

What price do you imagine SpaceX Operations would charge to SpaceX R&D for a FH-based Mars precursor mission? It would have to cover at least the cost of an expended upper stage (used for Earth departure), the payload integration, and the launch operations. Anything else?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 02/21/2016 02:37 am
Three words: "Mars precursor missions", as in before BFR. For these SpaceX R&D is the customer, unless NASA decides to tag along for a cheap secondary payload ride.

What price do you imagine SpaceX Operations would charge to SpaceX R&D for a FH-based Mars precursor mission? It would have to cover at least the cost of an expended upper stage (used for Earth departure), the payload integration, and the launch operations. Anything else?

If the people are already on the payroll, the pads in place, props are as little of a launch cost as Musk says, and they use previously landed boosters and/or center cores, such flights could be quite cheap.

IMO, FH was going to wait for F9 FT from the get-go to save developing, or redeveloping, it three times instead of only once. Also, such missions would allow the testing of necessary techs such as ISRU concepts, robotics, comms etc.

Let's not forget SpaceX's mission statement. Other launches and R&D are the means to that goal. What others think is moot.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LouScheffer on 02/21/2016 03:14 am
SpaceX has been clear from the start that FH development was a lower priority than F9 work.  As such they have been quite consistent in delaying it whenever there was more-important F9 work to do (F9 1.1, F9 FT, RTF, recovery, etc)

In some cynical, game-theoretic way, it might be good for SpaceX to delay the FH.   As long as the FH is not certified, their main competitor is forced to keep making Delta-IV Heavies.  These are expensive, keep a lot of engineers tied up, and create bad publicity with high prices to the government.

Conversely, once the FH is certified, ULA can drop the Delta-IV entirely, close several pads, lower prices, and assign more engineers to the newer projects such as Vulcan and ACES.  ULA is probably rooting for SpaceX to certify the F9, so they can streamline their own operations.

So in some "bad for me but worse for you" way, it might pay SpaceX to keep delaying the FH.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 02/21/2016 11:49 am
SpaceX has been clear from the start that FH development was a lower priority than F9 work.  As such they have been quite consistent in delaying it whenever there was more-important F9 work to do (F9 1.1, F9 FT, RTF, recovery, etc)

In some cynical, game-theoretic way, it might be good for SpaceX to delay the FH.   As long as the FH is not certified, their main competitor is forced to keep making Delta-IV Heavies.  These are expensive, keep a lot of engineers tied up, and create bad publicity with high prices to the government.

Conversely, once the FH is certified, ULA can drop the Delta-IV entirely, close several pads, lower prices, and assign more engineers to the newer projects such as Vulcan and ACES.  ULA is probably rooting for SpaceX to certify the F9, so they can streamline their own operations.

So in some "bad for me but worse for you" way, it might pay SpaceX to keep delaying the FH.

When FH is certified, the entire heavy market will be theirs. This is a premium market for which Delta Heavy will be soon charging one billion dollars a pop and SpaceX can charge whatever they want...

The above market share discussion missed the medium launch market (though somewhat off topic here)...
VEGA et al charge $40M a launch for these payloads -- soon to be the range of F9 or side booster reusable prices.  The more rapidly these cores are turned around, the bigger share of the market will be captured -- in both directions.

This reference from the Ariane thread is informative. Page 8 for medium market; good statistics for all commercial markets.

http://www.isae-alumni.net/docs/2015152450_presentation-airbus-safran-launchers-2015.pdf

What is most impactful on the (beloved by some) status quo is that every launch taken off the table by SpaceX makes the business case for whomever lost that launch less tenable.  We see this at ULA where they are in an existential crisis (USAF stating publically in Congressional hearings) because they are going to lose half of the market and at Ariane where competition has them scrambling. Other launch businesses are disappearing -- weakest in reliability first.  Boeing's venture Sealaunch is gone.  Proton is losing market share, too. Zenit near last launch if not already past that point...

The 'forcing function' now has begun to engage.  The status quo will be swept away (good riddance) unless SpaceX screws up terribly.  Many are still hoping this happens.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 02/21/2016 03:23 pm
Thanks for the pdf.

The markets are that FH if it captures 50% of the heavy market would be flying 3-4 times per year. And I agree that SpaceX will expand its market reach due to the price of both its RTLS F9 and RTLS 3core FH into smaller payload markets expanding to 60% of market totals such that FH could be doing in 2018-2019 as many as 8 launches mostly RTLS type of which 6 would be commercial and 2 US gov. F9 would be doing 6 commercial and 6 government (3-4 CRS, 1-2 CC, 0-2 other gov).

FH's future looks to be a busy booster doing mostly RTLS 3core type flights. This should get its price in this mode to close to what the F9 price is now. With the F9 price to be low enough to be be a stiff competitor for the small-medium payloads 2-3.2mt payloads when used in the RTLS mode (under $40M per launch).

The total commercial market at (21-25) and over 10 in the FH RTLS use range means that a capture of 60% of the market due to price would have the FH eventually flying 6 times per year just for commercial sats. Now add a few US government (1-2) and SpaceX internal (1-6) it could reach a flight rate of 14 per year.

FH will be a workhorse HLV-SHLV. SHLV is a LV that can do 50+mt to LEO. FH is an SHLV only in its expendable mode.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 02/21/2016 04:53 pm
@ AncientU

I don't know where you got the Airbus/Safran presentation, marked confidential BTW!, but it's very interesting, Thanks! 

First passover suggests the easiest market for SpaceX to grow share is in the small sat market competing against VEGA and Dnepr with used F9-FT cores.   I'll be busy translating French to English for a while now.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 02/21/2016 07:03 pm
@ AncientU

I don't know where you got the Airbus/Safran presentation, marked confidential BTW!, but it's very interesting, Thanks! 

First passover suggests the easiest market for SpaceX to grow share is in the small sat market competing against VEGA and Dnepr with used F9-FT cores.   I'll be busy translating French to English for a while now.

The presentation was here:

http://forum.nasaspaceflight.com/index.php?topic=31494.msg1490822#msg1490822

Interesting how they also recognize the potential of sky-fi (page 6).

Also note that flying pairs of these sats would still be RTLS mass range for FT. Takes two off the table at a time, just like FH could.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Rik ISS-fan on 02/21/2016 08:24 pm
I just found the presentation when I was googling for Ariane 6. I didn't realize it was confidential.
Moderators; do we have to delete the link's?

I still doubt if the Falcon Heavy will be structurally strong enough to cope with 50+mT payload on top of the second stage. written differently, I think the structure of a Falcon Heavy capable of launching 50+mT would be inefficiently heavy because the stage diameter is to small. The current envisioned Falcon Heavy is ment for 5-10mT payloads that are to heavy for Falcon 9FT. But with a Raptor upper-stage on the F9-FT most likely the same capability will be achieved. I think the Raptor Upperstage will get the same diameter as the payload fairing, and will have the same or less trust level ~900kN as the Merlin 1Dv-FT. This stage would be less overweight to cope with the buckling loads of a 50mT+ payloads.

Was the problem discovered during the return to flight with second stage re-ignition not related to the trust level of the upper-stage being to high. resulting in to high accelerations. The re-ignition is at a T/W of >3, resulting in a acceleration of >3G when the engine can't be ignited at a lower trust level. Most upper-stages have trust levels much lower than 200kN (45k lbf). So it might be beter to make an in-orbit stage (super-Draco) to launch large comsats with a three stage system, instead of a two stage system. Direct GTO injections are then also possible.
I also think that this might be cheaper than a dual or triple launch on a Falcon Heavy.
But first SpaceX has to show it can launch the payloads according to their manifest, and that they are reliable with they were not until now. A client doesn't like experiments on the flight of his >200mln satellite. And with the super chilled LOx SpaceX is experimenting on each flight. So it might be a wrong design decision to optimize for ground transport instead of optimized structural dimensions. A larger diameter first stage with a volume that would  eliminate LOx near it's freezing point, might be lighter than the current stage. And possibly this weight saving compensates the higher drag forces (skin friction drag). So you end up with the same system efficiency.       
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 02/21/2016 08:45 pm
I still doubt if the Falcon Heavy will be structurally strong enough to cope with 50+mT payload on top of the second stage. written differently, I think the structure of a Falcon Heavy capable of launching 50+mT would be inefficiently heavy because the stage diameter is to small.

The currently advertised capability for Falcon Heavy is 53mT to LEO.  Are you thinking that everyone involved with the design of the Falcon family has not considered how a 53mT mass interacts with the Falcon Heavy?

Think of this from a different point of view - no one needs a single mass that is 53mT in LEO, so SpaceX is not in a competition to see who can lift the largest amount of mass.  So if anything it's likely that 53mT is deemed as a safe load for Falcon Heavy.  And the promised new capacity numbers may show that.

But for me I think SpaceX knows what they are doing, and understand what is possible for Falcon Heavy from an engineering standpoint.

Quote
But first SpaceX has to show it can launch the payloads according to their manifest, and that they are reliable with they were not until now.

Delays are not uncommon in the launch industry, and that is one of the reasons why launch customers usually order a back launch - in case something is not going right with their primary choice.

So I think the free market will sort this out.  Customers that are looking for lower launch costs but can trade some time will stick with SpaceX during the times they have delays, but other customers who have time to market constraints may change to another launch provide.  And this has already happened.  So the free market works, even for SpaceX.

Quote
A client doesn't like experiments on the flight of his >200mln satellite.

Here again the free market has an influence, but SpaceX appears to be spending a lot of effort to work with customers so that they understand the risks of what they are doing.  And the customers understand the eventual long-term rewards, which is much lower launch costs, and money is an important factor.

But since experimentation for the sake of experimentation is very expensive (even for SpaceX), I don't see them changing what they are doing.

Quote
A larger diameter first stage with a volume that would  eliminate LOx near it's freezing point, might be lighter than the current stage.

OK, but that would mean they would have to build a new factory to replace the one in California, and build a new test facility to test the one they have in Texas.  So that is not a solution they can implement today, nor probably not for quite a few years down the road.  Maybe the factory they will use to build the BFR will allow that, but by the time we get to that point the market may be far different.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Rik ISS-fan on 02/21/2016 10:09 pm
The currently advertised capability for Falcon Heavy is 53mT to LEO.  Are you thinking that everyone involved with the design of the Falcon family has not considered how a 53mT mass interacts with the Falcon Heavy?

Think of this from a different point of view - no one needs a single mass that is 53mT in LEO, so SpaceX is not in a competition to see who can lift the largest amount of mass.  So if anything it's likely that 53mT is deemed as a safe load for Falcon Heavy.  And the promised new capacity numbers may show that.

But for me I think SpaceX knows what they are doing, and understand what is possible for Falcon Heavy from an engineering standpoint.
I think SpaceX calculated the performance of the FH with preliminary calculation methods. I think the capability to Mars (13,2mT, the same payload as Falcon 9FT) is achievable with the F9 upper stage. The core stage (that is structurally different than the boosters and the F9FT first stage), can most likely handle the GTO loads (21,2mT). Most likely the core for LEO performance is different than the GTO and escape core, and it is a lot heavier.
I also think that SpaceX has a lot more on it's drawing board than we think. How did the Raptor Upper-stage development came out of the blue. Because SpaceX already knew, or the engineers discovered during the detailed design of falcon heavy, that it was more efficient to increase the upper-stage diameter to the diameter of the payload fairing for the GTO FH.
For the LEO capability they will most likely develop a larger payload fairing and the same large diameter upper-stage. The core stage will most likely be heavier and have the same diameter. (or they assume that the LEO performance is a fuel tank; the upper-stage.)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 02/21/2016 10:31 pm
For the LEO capability they're probably going to start thinking about it whenever the first such payload appears on the horizon which will probably give them plenty of time because such a payload would take a few years to develop and build, too.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: S.Paulissen on 02/21/2016 11:10 pm
The currently advertised capability for Falcon Heavy is 53mT to LEO.  Are you thinking that everyone involved with the design of the Falcon family has not considered how a 53mT mass interacts with the Falcon Heavy?

Think of this from a different point of view - no one needs a single mass that is 53mT in LEO, so SpaceX is not in a competition to see who can lift the largest amount of mass.  So if anything it's likely that 53mT is deemed as a safe load for Falcon Heavy.  And the promised new capacity numbers may show that.

But for me I think SpaceX knows what they are doing, and understand what is possible for Falcon Heavy from an engineering standpoint.
I think SpaceX calculated the performance of the FH with preliminary calculation methods. I think the capability to Mars (13,2mT, the same payload as Falcon 9FT) is achievable with the F9 upper stage. The core stage (that is structurally different than the boosters and the F9FT first stage), can most likely handle the GTO loads (21,2mT). Most likely the core for LEO performance is different than the GTO and escape core, and it is a lot heavier.
I also think that SpaceX has a lot more on it's drawing board than we think. How did the Raptor Upper-stage development came out of the blue. Because SpaceX already knew, or the engineers discovered during the detailed design of falcon heavy, that it was more efficient to increase the upper-stage diameter to the diameter of the payload fairing for the GTO FH.
For the LEO capability they will most likely develop a larger payload fairing and the same large diameter upper-stage. The core stage will most likely be heavier and have the same diameter. (or they assume that the LEO performance is a fuel tank; the upper-stage.)

Considering that Centaur, a 3m stage with a minimum wall thickness of 0.010", can launch nearly 19000kg payload  into orbit using only pressure stabilization with ~50psig, I think SpaceX can support it just fine with their tank pressure being the same and -not- completely pressure stabilized.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 02/21/2016 11:30 pm
For the LEO capability they're probably going to start thinking about it whenever the first such payload appears on the horizon which will probably give them plenty of time because such a payload would take a few years to develop and build, too.

Propellant is such a payload.
Trust me, they've started thinking.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 02/21/2016 11:36 pm
Why should they ship 50t of propellant to LEO with no place to go there.
They will surely have started thinking but it makes no sense that they've started designing, F9 in all its variants will probably see a few more iterations before they're going to ship such a payload.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 02/21/2016 11:41 pm
Considering that Centaur, a 3m stage with a minimum wall thickness of 0.010", can launch nearly 19000kg payload  into orbit using only pressure stabilization with ~50psig, I think SpaceX can support it just fine with their tank pressure being the same and -not- completely pressure stabilized.
It can't. It needs the external 5m fairing to get through max Q with such a payload.
This is exactly such a case.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sdsds on 02/21/2016 11:51 pm
Centaur [...] can launch nearly 19000kg payload  into orbit using only pressure stabilization
It can't. It needs the external 5m fairing to get through max Q with such a payload.
This is exactly such a case.

Right. And it's not just axial loads. With the 5m fairing there is also the Centaur Forward Load Reactor  to handle lateral loads induced during flight. I wonder if ULA (or Contraves/RUAG?) has a patent on that? ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: 2552 on 02/21/2016 11:57 pm
Falcon Heavy gets like 20 tons to LEO GTO expendable. A couple of SRBs doesn't do that.

That is true, but using FH in expendable mode for +6.5 ton comsats is what I was suggesting as overkill.   What can FH do to GTO when all cores are RTLS?  Or when the center core is DPL?   The reuse scenarios are the subject that is accurate to weigh alternate FH options against.

The SES-9 mission is interesting to the FH discussion, as it will inform a pretty good estimate of the max payload of F9-FT to GTO.   What then is the best solution to cover the gap between F9-FT to the lager and lucrative GTO payloads?   FH is the current SpaceX solution to that market.  It does not appear to be doing well.
Considering how high performance the SES9 mission is, it seems quite reasonable that 6.5+ ton satellites would have all cores recovered, and probably all return to launch site even.

With Raptor, Falcon Heavy may be able to put the biggest commsats through GTO while being FULLY reused.

And if they also go to a 5.2m Raptor first stage, maybe FH could send those 6.5+ tons satellites directly to GSO with full reusability.  8)

Edit: I wonder if that much extra performance is even necessary to do that. If a satellite that would've been launched to GTO would be launched to GSO instead using Raptor-FH, it could forego the extra hypergolic fuel (and engines(s)?) to transfer to GSO and would mass a lot less, reducing satellite build costs somewhat. Or if it would've used SEP instead of extra hypergolic fuel to transfer to GSO, being sent there directly to would save the months of transfer time, accelerating revenue generation.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: matthewkantar on 02/22/2016 04:51 am
Considering that Centaur, a 3m stage with a minimum wall thickness of 0.010", can launch nearly 19000kg payload  into orbit using only pressure stabilization with ~50psig, I think SpaceX can support it just fine with their tank pressure being the same and -not- completely pressure stabilized.

0.010" ?  I just mic'd two sheets of printer paper, they are almost as thick. I had read of the stainless on the Centaur stage being thin, but that is amazing. Crappy auto bodies are at least twice that thick.

Matthew

Edit: did a little bit of googling, original tanks in the 60's indeed .010", later tanks .014 and .016, wow.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 02/22/2016 06:10 pm
Considering that Centaur, a 3m stage with a minimum wall thickness of 0.010", can launch nearly 19000kg payload  into orbit using only pressure stabilization with ~50psig, I think SpaceX can support it just fine with their tank pressure being the same and -not- completely pressure stabilized.

0.010" ?  I just mic'd two sheets of printer paper, they are almost as thick. I had read of the stainless on the Centaur stage being thin, but that is amazing. Crappy auto bodies are at least twice that thick.

Matthew

Edit: did a little bit of googling, original tanks in the 60's indeed .010", later tanks .014 and .016, wow.
Trivia about stainless steel balloon tanks.

Atlas E/F was .017 at the top and increased thickness to .032 at the bottom and held 300Klb of LOX and RP-1. Atlas balloon tanks had never had a structural failure even in wildly uncontrolled vehicles doing cartwheels above the pads in early launches. Cartwheels was because one of the out booster engines shut down creating a large torque, an 180Klbf sized torque on a fully loaded vehicle.

Stainless steel balloon tanks have very high structural margins. Higher than >2:1. Much higher than the average aluminum alloy tanks.

The main reason for the covering of the centaur by the 5.2m faring is thermal not structural. If you need more strength all you have to do is use a slightly thicker stainless and a higher pressure. Atlas E/F used 100psi flight pressure.

Back to SpaceX. SpaceX gains its high flight structural margins by a semi-balloon tank design by putting the tank skin into a stretch instead of a compression mode during flight. This allows SpaceX to use thinner walls and lower weight tanks. Which is why a F9 US has such a low dry weight, as low as a ULA DCSS. For a Raptor US, SpaceX would be able to get close to the phenomenal low dry weight of an ACES stage on Vulcan.

The real telling point is the PF of the US. The F9 current US has a PF of ~96%. The Centaur only 91%. The Vulcan/ACES would have also 96% but a Raptor stage could be as much as 97%.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LouScheffer on 02/22/2016 09:14 pm

Trivia about stainless steel balloon tanks.

Atlas E/F was .017 at the top and increased thickness to .032 at the bottom and held 300Klb of LOX and RP-1.

Stainless steel balloon tanks have very high structural margins. Higher than >2:1. Much higher than the average aluminum alloy tanks.

Atlas E/F used 100psi flight pressure.

Perhaps I'm missing something, but I can't see how this hangs together.  Consider a 1 meter piece of the tank.  100 psi is 689,000 N/m^2.  The tank is 4.9 meters in diameter, so the total force pushing two halves apart is 3.38 MN.  Each side has to resist half of this, or 1.69 MN.  0.017 inches is 0.4318 mm, so the total cross sectional area is 0.0004318 meters.  Thus the required tensile strength is 1.69 MN/0.0004318 m = 3.91e9 N/m^2, or 567,000 PSI.

But stainless steel does not seem to be this strong.  Atlas uses type 301 stainless steel, but in the book "Materials for Aircraft, Missiles, and Space Vehicles" it says "In engineering applications type 301 stainless steel is frequently used at room-temperature yield and tensile strengths of 200,000 and 220,000 psi, respectively, which are obtained by cold rolling the steel".

So instead of a factor of 2, it seems to have a factor of 0.4 .  Now Atlas rockets clearly did not explode from pressurization loads, so something in this calculation is fishy.  But I can't see what it is.  Anyone got any suggestions?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/22/2016 09:32 pm
1) cold-working increases strength beyond 220ksi.
2) reduced temperatures increases tensile strength
3) ullage pressure is lower than 100psi
4) diameter is less than 5m. 3m for Atlas and typical Centaur.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: edkyle99 on 02/22/2016 09:51 pm
4) diameter is less than 5m. 3m for Atlas and typical Centaur.
3.048 meters (120 inches) diameter to be exact.

 - Ed Kyle
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LouScheffer on 02/23/2016 01:38 am
4) diameter is less than 5m. 3m for Atlas and typical Centaur.
This reduces the stress to 2.43 GPascal, or 352 KPSI
Quote
1) cold-working increases strength beyond 220ksi.
2) reduced temperatures increases tensile strength
The combination of these might get up to 325 KPSI, according to "EVALUATION OF SPECIAL 3O1-TYPE STAINLESS STEEL FOR lMPROVED LOW-TEMPERATURE NOTCH TOUGHNESS OF CRYOFORMED PRESSURE VESSELS" at http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19660015958.pdf, or similarly
http://www.tokkin.com/materials/stainless_steel/spring

However, the low temperature does not help for the kerosene tank, and for the oxygen tank it would depend on the temperature of the ullage gas.  And LOX is not cold enough to get enough strength.

Even with both temperature and cold working, you only get a safety factor of 1 or thereabouts.
Quote
3) ullage pressure is lower than 100psi
This is my guess.  Maybe 100 psi is the pressure at the bottom of the tank, but the top of the tank is only half that.  This matches the thickness variation.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/23/2016 01:50 am
4) diameter is less than 5m. 3m for Atlas and typical Centaur.
This reduces the stress to 2.43 GPascal, or 352 KPSI
Quote
1) cold-working increases strength beyond 220ksi.
2) reduced temperatures increases tensile strength
The combination of these might get up to 325 KPSI, according to "EVALUATION OF SPECIAL 3O1-TYPE STAINLESS STEEL FOR lMPROVED LOW-TEMPERATURE NOTCH TOUGHNESS OF CRYOFORMED PRESSURE VESSELS" at http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19660015958.pdf, or similarly
http://www.tokkin.com/materials/stainless_steel/spring

However, the low temperature does not help for the kerosene tank, and for the oxygen tank it would depend on the temperature of the ullage gas.  And LOX is not cold enough to get enough strength.

Even with both temperature and cold working, you only get a safety factor of 1 or thereabouts.
Quote
3) ullage pressure is lower than 100psi
This is my guess.  Maybe 100 psi is the pressure at the bottom of the tank, but the top of the tank is only half that.  This matches the thickness variation.
It's a combination of those things, and I wasn't guessing. 100psi is higher than the ullage pressure in either tank, but the liquid oxygen tank has higher ullage pressure than the kerosene tank, which is compensated somewhat by the lower temperature of the liquid oxygen.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 02/23/2016 01:52 am
And if they also go to a 5.2m Raptor first stage, maybe FH could send those 6.5+ tons satellites all the way to GSO and recover all stages.

I'm sure you meant second stage. You may want to edit that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: John-H on 02/23/2016 02:07 am
Pressure variation is about 0.5 psi for foot of hight. That is for water at 1 g.  For fuel at much higher accelerations it would be  more.

John
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 02/23/2016 02:11 am
Pressure variation is about 0.5 psi for foot of hight. That is for water at 1 g.  For fuel at much higher accelerations it would be  more.

John
But it doesn't get much higher accelerations until most of the fuel is drained, which reduces the height. So the effect is basically canceled out after initial lift-off! :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Katana on 02/23/2016 05:30 am
301 or 304 type steel normally yields 200MPa, could be cold worked to 400MPa. Reserve 2:1 margin, you still have 200MPa...

Now 2.4GPa...10 times...

Also 100psi is quite high, as high as chamber pressure of pressure fed engines without pump.
4) diameter is less than 5m. 3m for Atlas and typical Centaur.
This reduces the stress to 2.43 GPascal, or 352 KPSI
Quote
1) cold-working increases strength beyond 220ksi.
2) reduced temperatures increases tensile strength
The combination of these might get up to 325 KPSI, according to "EVALUATION OF SPECIAL 3O1-TYPE STAINLESS STEEL FOR lMPROVED LOW-TEMPERATURE NOTCH TOUGHNESS OF CRYOFORMED PRESSURE VESSELS" at http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19660015958.pdf, or similarly
http://www.tokkin.com/materials/stainless_steel/spring

However, the low temperature does not help for the kerosene tank, and for the oxygen tank it would depend on the temperature of the ullage gas.  And LOX is not cold enough to get enough strength.

Even with both temperature and cold working, you only get a safety factor of 1 or thereabouts.
Quote
3) ullage pressure is lower than 100psi
This is my guess.  Maybe 100 psi is the pressure at the bottom of the tank, but the top of the tank is only half that.  This matches the thickness variation.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: acsawdey on 02/23/2016 03:35 pm
Let's inject some real data into this, shall we?

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19740009453.pdf (http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19740009453.pdf)

Page 63 of this pdf has an actual calculation of allowable pressure for each section of an Atlas F. It's at elevated temperature because the study was looking at using an expended booster to do re-entry heating studies for the shuttle. But for each section of the tank we have the skin thickness, the assumption for temperature, and what Convair thought was the allowable ultimate hoop stress.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: acsawdey on 02/23/2016 03:59 pm
Here's another one:

http://ntrs.nasa.gov/search.jsp?R=19790019063 (http://ntrs.nasa.gov/search.jsp?R=19790019063)

An unfortunate Atlas was found to have corrosion and got cut up and studied. On page 83 of the pdf we see that the strength at room temp for uncorroded specimens was 226-229 ksi or 1560-1580 MPa. Also the figure on that page says that the design required strength is 184 ksi, and "max stress" is 78 ksi. I'm not sure which direction that stress goes but it seems like they cut the test pieces across the seam welds and tested in that direction, not around the circumference. But even in it's corroded condition the tank was filled with RP-1 and pressurized to 68 psi, and leaked but did not fail.
 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LouScheffer on 02/23/2016 06:27 pm
Let's inject some real data into this, shall we?

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19740009453.pdf (http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19740009453.pdf)

Page 63 of this pdf has an actual calculation of allowable pressure for each section of an Atlas F. It's at elevated temperature because the study was looking at using an expended booster to do re-entry heating studies for the shuttle. But for each section of the tank we have the skin thickness, the assumption for temperature, and what Convair thought was the allowable ultimate hoop stress.

Two interesting things from this:
(a) they are doing the calculations just like we are
(b) they are using an ultimate factor of safety of 1.25 (for hoop stress)

http://ntrs.nasa.gov/search.jsp?R=19790019063 (http://ntrs.nasa.gov/search.jsp?R=19790019063)

An unfortunate Atlas was found to have corrosion and got cut up and studied. On page 83 of the pdf we see that the strength at room temp for uncorroded specimens was 226-229 ksi or 1560-1580 MPa. Also the figure on that page says that the design required strength is 184 ksi, and "max stress" is 78 ksi. I'm not sure which direction that stress goes but it seems like they cut the test pieces across the seam welds and tested in that direction, not around the circumference. But even in it's corroded condition the tank was filled with RP-1 and pressurized to 68 psi, and leaked but did not fail.
 
I too think this is stress along the tank, not hoop stress.  (For a balloon tank filled with gas the stress along the tank is half the hoop stress.  If the tank is partially filled the axial stress is determined by the ullage pressure only.)  They explicitly say that the max stress in flight is 78 ksi. but if that was hoop stress it would imply a max tank pressure of 41.6 psi for a wall thickness of 0.032 and a 120 inch diameter tank.  But they pressurized to 68 psi (which gives 127 ksi hoop stress for a 120 inch tank). 

So perhaps they use a safety factor of >2 (184/78) along the tank, but a smaller factor for hoop stress, as they did above.  Also the material is stronger in this direction. 

 CRYOGENIC MATERIALS DATA HANDBOOK (http://www.dtic.mil/get-tr-doc/pdf?AD=AD0713619&Location=U2&doc=GetTRDoc.pdf), by the Air Force in 1970, page 420, gives higher strengths for 301 stainless that is cold-worked to 78% elongation - 390 ksi at LOX temp, 310 ksi at room temp, both in the strong direction (the other direction is about 10% weaker).  But from the above Atlas calculations (both of them), and the results of physically testing the material used to build Atlas, they do not appear to use these potentially greater strengths. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: intrepidpursuit on 02/23/2016 10:54 pm
None of this seems to be remotely about Falcon Heavy. Are they putting a Centaur on a Falcon? I don't think so.

"Next week" has come and gone and we have no FH data. Any further word on a data dump?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: S.Paulissen on 02/24/2016 06:08 pm
None of this seems to be remotely about Falcon Heavy. Are they putting a Centaur on a Falcon? I don't think so.

"Next week" has come and gone and we have no FH data. Any further word on a data dump?

No offense intended, but this post almost comes off myopic to the point of being obtuse.  It's quite clear how it's relevant to the question posed by ISS_Rik about how he doesn't see how the current upper stage can support a 50000+kg payload that SpaceX claims as a capability for Falcon Heavy. 

I responded by pointing out that Centaur had a minimum wall thickness of 0.010" and was capable of launching 18000+kg to orbit using pressure stabilization as a way to suggest that it's far from 'impossible' that SpaceX could launch 50000+kg to orbit on the existing upper stage. 

I realize that this is, in horrible defiance of our Lord-and-Savior Elon Musk (this is a joke), reasoning-from-analogy.  Since we're (read: I'm) not privy to the proprietary data of SpaceX upper stage architecture and there is a great deal of public data about Centaur, it is hardly irrelevant to invoke knowledge of what's possible with Centaur in order to make suggestions about Falcon's upper stage capability especially when SpaceX themselves states their mass fractions are possible because of pressure stabilization, indicating it's not a huge mistake to use Centaur as a baseline to estimate what's possible with that type of design.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Katana on 02/29/2016 01:51 pm
http://asm.matweb.com/search/SpecificMaterial.asp?bassnum=MQ304A
Tensile strength ultimate 505MPa Yield 215MPa

http://www.northamericanstainless.com/wp-content/uploads/2010/10/Grade-301-301LN.pdf
Tensile strength 75ksi yield 30ksi
full hard tensile strength 185 ksi yield 140ksi
Here's another one:

http://ntrs.nasa.gov/search.jsp?R=19790019063 (http://ntrs.nasa.gov/search.jsp?R=19790019063)

An unfortunate Atlas was found to have corrosion and got cut up and studied. On page 83 of the pdf we see that the strength at room temp for uncorroded specimens was 226-229 ksi or 1560-1580 MPa. Also the figure on that page says that the design required strength is 184 ksi, and "max stress" is 78 ksi. I'm not sure which direction that stress goes but it seems like they cut the test pieces across the seam welds and tested in that direction, not around the circumference. But even in it's corroded condition the tank was filled with RP-1 and pressurized to 68 psi, and leaked but did not fail.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: robert_d on 03/05/2016 04:02 pm
Does anyone know the separation distance between the core cylinders of the Falcon Heavy? Spaceflight 101 just lists a 'span' of "12.2 meters".
Does anyone know if the Falcon 1 launches from 39A will use the same base structure as the Falcon Heavy or have its own? IS there a better name for that part of the ground equipment?
Does anyone know if there are any plans to launch human missions on Falcon Heavy? Is there a thread on this? Plans for a different 'trunk' that would include an engine and additional life support?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: philw1776 on 03/05/2016 08:35 pm
Now that F9 has racked up yet another successful launch is there any word on when the February promised release of specs on the Falcon Heavy, etc. will be released?  Why the delay after a short schedule for release?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: the_other_Doug on 03/06/2016 12:18 am
Now that F9 has racked up yet another successful launch is there any word on when the February promised release of specs on the Falcon Heavy, etc. will be released?  Why the delay after a short schedule for release?

We're not SpaceX.  We don't know.

My guess is that it remains a moving target, and therefore they don't want to get pinned down.  But I'm not SpaceX, so I don't know...  all I can do is guess.  :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: woods170 on 03/08/2016 01:40 pm
Over-promising and under-delivering has just cost Falcon Heavy a mission:

http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/ (http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/)

And Arianespace just lucked out in filling a hole in their manifest.

And the same thing has just cost Falcon Heavy a second mission:

http://spacenews.com/inmarsat-worried-about-spacex-falcon-heavy-delays-books-reservation-for-ils-proton-launch/ (http://spacenews.com/inmarsat-worried-about-spacex-falcon-heavy-delays-books-reservation-for-ils-proton-launch/)

This time the beneficiary is ILS.
There weren't many payloads booked on FH to begin with, and now two of them are gone.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/08/2016 01:56 pm
Over-promising and under-delivering has just cost Falcon Heavy a mission:

http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/ (http://spaceflightnow.com/2016/02/15/viasat-trades-in-falcon-heavy-launch-for-ariane-5/)

And Arianespace just lucked out in filling a hole in their manifest.

And the same thing has just cost Falcon Heavy a second mission:

http://spacenews.com/inmarsat-worried-about-spacex-falcon-heavy-delays-books-reservation-for-ils-proton-launch/ (http://spacenews.com/inmarsat-worried-about-spacex-falcon-heavy-delays-books-reservation-for-ils-proton-launch/)

This time the beneficiary is ILS.
There weren't many payloads booked on FH to begin with, and now two of them are gone.
According to the article, this is a "Plan B," not a straight up cancellation. They are booking an option on Proton. If FH launches, then the Plan B Proton will be used for a different ILS satellite. If FH has further delays, then Inmarsat can launch the first satellite on Proton instead. Sounds like a good plan for Inmarsat, and I don't think it's bad news for SpaceX any more than delaying is already bad.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 03/08/2016 02:47 pm
Nobody has any proof that they're deliberately flat-out delaying. More likely that they keep iterating upgrades which cause them to change FH's design slightly, but the pressure is on now. It will fly this year.

FH can afford to lose booked launches to lateness anyway (as have incomplete LVs). Once it flies, then they'll get orders flooding in. These pre-orders have little bearing on FH's end market, because people will start booking sats again once the rocket is more than a collection of parts waiting to be put together. Better to ensure it flies first, flys right, and performs as advertised. That wins over any timescale, and will win more customers.

Gravely muttering about timescales and how we've all been waiting since 1012 misses the nature of the business. An LV provider does not need to get every sat that has been offered to them. We only whirl out an entire kremlinology bureau over it because it's SpaceX and we're all fans in one way or another.

(Obligatory Elon time Meme).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: DJPledger on 03/08/2016 06:28 pm
SpaceX need to get FH launching ASAP otherwise all their customers for it will walk off to other launch vehicle providers. If FH ends up with no paying customers then SpaceX might as well cancel it and replace it with a Raptor powered LV.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dorkmo on 03/08/2016 06:56 pm
If you build it, they will come.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GreenShrike on 03/08/2016 10:13 pm
SpaceX need to get FH launching ASAP otherwise all their customers for it will walk off to other launch vehicle providers.

Sure -- at least until Falcon Heavy does fly, at any rate, whereupon the competitiveness of FH launches will assure SpaceX some chunk of heavy GTO launches. Naturally more competitiveness will net them a bigger chunk.

Not having FH launching now costs them only near and maybe some medium term launches. As soon as it does fly though, they'll have customers with payloads to fly. And I'd venture that comsat operators are more likely to tolerate delay in a launch vehicle which has never flown than to risk their flagship comsats on constant vehicle revisions of the magnitude of F9's 1.0 -> v1.1 -> FT upgrades.

If FH ends up with no paying customers then SpaceX might as well cancel it and replace it with a Raptor powered LV.

The only way FH winds up with no customers is if it never flies and is just cancelled. Since FH undoubtedly figures prominently in SpaceX's comsat constellation -- not to mention their initial Mars plans -- there's no way FH will get cancelled while Elon is running the show. SpaceX needs the FH for their own use, irrespective of anyone else.

Paying customers are just a bonus.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 03/08/2016 10:51 pm
With no barge landing successful yet we don't know how competitive FH will be. SpaceX is currently throwing resources into a lot of things in parallel, since they now have to complete Raptor somewhat soonish FH might not be a top priority, an ordinary Falcon with a Raptor upper stage might turn out to be the more profitable launcher for comsats.

Also lets not forget that F9 is now already able to launch all but the heaviest comsats so there's less urgency to get FH ready.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GreenShrike on 03/08/2016 11:55 pm
With no barge landing successful yet we don't know how competitive FH will be.

Worst case, with zero reuse and fully expendable launches each time, it'll cost, what $60M for an F9 plus 2 x $40M for a pair of F9 S1-derived boosters? IOW, a hell of a lot less than Ariane5 for a whole bunch more performance. SpaceX would need dual or triple sat dispensers, which would suck, to use up the performance (20t+ to GTO?), but they could do it.

SpaceX is currently throwing resources into a lot of things in parallel, since they now have to complete Raptor somewhat soonish FH might not be a top priority,

Raptor is years away. FH will almost certainly be flying within a year --  a half-year if they manage to get the current schedule to stick. And with no further F9 upgrades to mess up the Heavy's core design, actual progress in terms of bending metal shouldn't be hard to come by.

an ordinary Falcon with a Raptor upper stage might turn out to be the more profitable launcher for comsats.

Maybe -- in 2020 when a Raptor stage might be usable.

Also lets not forget that F9 is now already able to launch all but the heaviest comsats so there's less urgency to get FH ready.

Only until you remember that the point of SpaceX *isn't* to launch heavy comsats -- it's to get to Mars. And there are a limited number of Mars launch windows to get exploration done before MCT flies. I really don't think they want to miss the 2018 window.

Everyone else can go buy other rides if they need to, but SpaceX can't. *SpaceX* needs Falcon Heavy flying.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/09/2016 12:31 am
...since they now have to complete Raptor somewhat soonish FH might not be a top priority, an ordinary Falcon with a Raptor upper stage might turn out to be the more profitable launcher for comsats.
...
Interesting theory, but false. FH is most certainly a top priority. They won't be done with Raptor on the test stand until 2018, and delays could easily happen to that. And an engine is not a stage. A Raptor-optimized stage would likely be larger in diameter, possibly even reusable-capable. That means new tooling at a minimum but possibly a HUGE development cycle if it's reusable.

They have everything they need for FH now. They have a launch pad capable of it (two of them, actually), plus a test stand that is also capable of it, plus a matured Falcon 9 platform. Raptor would need a bunch of new developments and pad equipment, and would push the timeline for launching the most /profitable/ satellites far to the right.

You'll see Falcon Heavy at the launch site this year. Not entirely sure it'll launch (they still need to test fire it in McGregor, which I expect to see soon, and problems can arise on the launch pad), but I'd bet money they'll have it at the launch site this year.


...I COULD see them switching to Raptor-on-Falcon9 if, say, they have 2 Falcon Heavy failures in a row or something (God forbid). And they /may/ retire Falcon Heavy in favor of a large, two-stage, single-stick methane vehicle eventually, but they are SO CLOSE at this point to completing all their main tasks that they've been promising for their first decade of existence, that I'd doubt they'd risk it all again by abandoning Falcon Heavy this far into development, with the finish line in site. That's like billions of dollars in lost revenue.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/09/2016 12:33 am
As far as we know, SpaceX may be bending metal right now on Falcon Heavy. Or even started getting it integrated and ready to ship to McGregor.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Damon Hill on 03/09/2016 04:27 am
What hardware would be unique to Falcon Heavy, including propellant cross-feed?  Will the first few Heavies even have cross-feed, or is that reserved for highest performance missions?

--Damon
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/09/2016 04:33 am
What hardware would be unique to Falcon Heavy, including propellant cross-feed?  Will the first few Heavies even have cross-feed, or is that reserved for highest performance missions?

--Damon
Correct. They're not bothering with cross-feed right now. Also, thrust increases for Merlin 1D and propellant densification means they can get about the same performance without it. Shotwell hinted that if someone needed a 60 ton payload, then they would do it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 03/09/2016 04:41 am
I didn't mean to imply that SpaceX stopped working on FH, just that it's got a lower priority.
I don't expect it to fly this year, for example.

They will of course still need it until they have e.g. an Raptor based US but they have very few flights booked on it and there are very few payloads that actually need it.

I'm pretty sure they must be somewhat short on development resources (that's always your bottleneck in growth scenarios since you can't scale it at will) so they will have to prioritize and FH, Raptor, crew Dragon, the sat activities... a lot going on.

Only until you remember that the point of SpaceX *isn't* to launch heavy comsats -- it's to get to Mars.
Yea, that thing. Sorry, I don't buy the hype. That may be their vision, it's not what they are doing and what pays for the breakfast cereals.
If Elon wants to go to Mars someone has to pay the bill and that someone is governments and comsat customers.
There's about one government payload that needs FH and they are not yet bidding for that one so FH is currently exclusively a comsat launcher. And in that heavy segment they are not that much cheaper than Ariane as they are on the smaller birds,
Need to close a business case for that one.

FH looked like a high priority project before they new they could get as much performance out of F9 as they do now but the mere fact that they tweaked F9 with all the iterations before simply going to the heavy shows their priorities and expected cost structure.

Quote
And there are a limited number of Mars launch windows to get exploration done before MCT flies. I really don't think they want to miss the 2018 window.
Don't think they've got a few hundred million to waste on such a stunt by 2018. So far most of their short-term experiments were actually financed by NASA or other customers and I don't see that happen for a Mars mission.

MCT is a massively expensive dream. Unless they find some government that's willing to churn out billions by the dozen that thing won't fly before the '40s or '50s at earliest.
Plenty of time for other Falcon versions before that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/09/2016 05:04 am
Who says they'd waste hundreds of millions of dollars?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 03/09/2016 06:05 am
Who says they'd waste hundreds of millions of dollars?

Well, "waste" is of course a question of perspective but to do meaningful research 2018 is too short a timing and an FH flight plus a payload to Mars plus mission control plus comms towards Mars will certainly cost a few hundred million $$$
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Damon Hill on 03/09/2016 06:08 am
What hardware would be unique to Falcon Heavy, including propellant cross-feed?  Will the first few Heavies even have cross-feed, or is that reserved for highest performance missions?

--Damon
Correct. They're not bothering with cross-feed right now. Also, thrust increases for Merlin 1D and propellant densification means they can get about the same performance without it. Shotwell hinted that if someone needed a 60 ton payload, then they would do it.

Ah, so.  Don't know if I'm disappointed in that or not.  Cross-feed might be tricky and involves some significant changes compared to a 'simple' Heavy configuration that uses mostly-stock Falcon 9s.  It'll be a bit more entertaining getting all that hardware to work in reliable triplicate, especially the dual landing part, to say nothing of getting the core back on a very downrange barge--I don't see that ever doing a flyback.

--Damon
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 03/09/2016 06:17 am

If Elon wants to go to Mars someone has to pay the bill and that someone is governments and comsat customers.
There's about one government payload that needs FH and they are not yet bidding for that one so FH is currently exclusively a comsat launcher. And in that heavy segment they are not that much cheaper than Ariane as they are on the smaller birds,
Need to close a business case for that one.

Besides Mars there is the DOD market. Gwynne Shotwell has promised in a Congress Hearing that Falcon Heavy will be ready and certified by 2018. And even if Mars is their primary driver, Elon Musk really, really wants to have the ability to fly the full range of DOD payloads, if only to take the argument from ULA that he can't.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 03/09/2016 06:22 am

If Elon wants to go to Mars someone has to pay the bill and that someone is governments and comsat customers.
There's about one government payload that needs FH and they are not yet bidding for that one so FH is currently exclusively a comsat launcher. And in that heavy segment they are not that much cheaper than Ariane as they are on the smaller birds,
Need to close a business case for that one.

Besides Mars there is the DOD market. Gwynne Shotwell has promised in a Congress Hearing that Falcon Heavy will be ready and certified by 2018. And even if Mars is their primary driver, Elon Musk really, really wants to have the ability to fly the full range of DOD payloads, if only to take the argument from ULA that he can't.

Sure, I said that.
But still, even if they are able to compete and win flights of that DIVH payload we're still talking 202x for an actual flight and 2017/18 for an FH demo flight. Not really urgent all of that is...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 03/09/2016 06:26 am
Besides Mars there is the DOD market. Gwynne Shotwell has promised in a Congress Hearing that Falcon Heavy will be ready and certified by 2018. And even if Mars is their primary driver, Elon Musk really, really wants to have the ability to fly the full range of DOD payloads, if only to take the argument from ULA that he can't.

Sure, I said that.
But still, even if they are able to compete and win flights of that DIVH payload we're still talking 202x for an actual flight and 2017/18 for an FH demo flight. Not really urgent all of that is...

To be certified in 2018 they need to fly this year. Or maybe very early next year and then two more flights in quick succession after that.

Edit: And they need to be certified in 2018 to fly DOD payloads in 2020 or 21.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 03/09/2016 06:30 am
Ah, forget about that. DOD wants to save money, too and Vulcan which is the likely competitor will not have flown by '18 as well. I'm pretty sure DOD would let them bid if they have flown at least once and opened the books and commit to do whatever level of certification DOD requires before the flight.
Let's remember they are having an existing customer relationship by then, it's not like last year when they were barely able to tell the actual configuration of the LV they were planning to bid.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 03/09/2016 01:36 pm
Uh huh....A single engine per core FH?! Raptor?

Duh...mounting posts. Whew!

https://twitter.com/MarcusReports/status/707259146513616897

@MarcusReports
Walking around the exhibit hall at #satellite2016. https://t.co/1TuHi13WYi
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rpapo on 03/09/2016 01:38 pm
Uh huh....A single engine per core FH?! Raptor?
Look closer.  What appears to be engines at first are simply the model's mounting posts.  Around them you can see the normal Merlins.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/09/2016 01:55 pm
Who says they'd waste hundreds of millions of dollars?

Well, "waste" is of course a question of perspective but to do meaningful research 2018 is too short a timing and an FH flight plus a payload to Mars plus mission control plus comms towards Mars will certainly cost a few hundred million $$$
Reused Falcon Heavy flying a reused Dragon with a payload that they might be able to get NASA to pay for, and perhaps even qualifying some upgrade to Falcon Heavy (in which case they would have to pay for the launch anyway or at least offer a ridiculously steep discount)... And what makes you think they would start working on it /now/? If SpaceX is interested in 2018, they'd ALREADY have been working on this.

SpaceX still has two DragonLab missions on the book (which I've been told they haven't given up on, yet), and they were planning to basically self-fund those. It'd make more sense to send one of them to Mars instead.

In spite of their early openness, SpaceX has several secret projects which they haven't publicized. They may have been working towards a 2018 mission for years.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 03/09/2016 02:01 pm
I'm pretty sure they must be somewhat short on development resources (that's always your bottleneck in growth scenarios since you can't scale it at will) so they will have to prioritize and FH, Raptor, crew Dragon, the sat activities... a lot going on.

I agree that development resources are constrained, but it works in the other direction, too: once you've hired "the best" engineers in XYZ field for $$$, you have to keep them busy.  Many of the development projects you mention have non-overlapping skill sets.

For example, the propulsion/big rocket engine guys were clearly working on "full thrust" Merlin as a priority.  Now that that work seems to be winding down, I'd expect them to start working on Raptor --- not Falcon Heavy, since the octoweb side of FH is pretty much "done", and not the commsat project or Dragon, etc. (A gross simplification to be sure, but we're talking "cumulative # of propulsion engineer hours" here, not "# of tasks".).

The bottlenecks are probably at MacGregor and LC-39A, not any of the other development projects you listed.  It will indeed be interesting to see how FH testing in squeezed in at MacGregor amongst their other contracted commercial and NASA F9 work.  At LC-39A, the tension seems to only be between crew Dragon (which needs some pad facilities constructed) and FH.  Recent work there seems to indicate that FH is what they are working on currently: they are installing rainbirds at the pad for FH, not dismantling the RSS or constructing the crew access tower.  Of course, there may be other logistical/scheduling reasons for doing the work in that order.

But based on visible evidence, the only place we can see FH taking a back seat to other work right now is at MacGregor.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 03/09/2016 02:19 pm
Reused Falcon Heavy flying a reused Dragon with a payload that they might be able to get NASA to pay for
Reused FH should be worth as much as a new one.
Reused Drageon: sure, or a used Ford Explorer or a bag of stones, doesn't matter if you want to throw dead weight towards Mars. Because that's what a "reused Dragon" would be once you leave LEO. No means of communication, electronics which probably won't survive the trip, too little power supply to work at Mars, no means of navigation...

And where's NASA's budget position for the payload, where is the payload (these things take time to develop) and then which payload do you want to fly on a dead spacecraft?

No, SpaceX is not going to Mars in '18.

Quote
And what makes you think they would start working on it /now/? If SpaceX is interested in 2018, they'd ALREADY have been working on this.
I have written that. It's the whole point of my argument: I think they are working on so many things in parallel that they have to prioritize and you can clearly see that FH is taking the hit in this, schedule wise. Now, of course you could prioritize a Mars payload at the expense of getting FH ready even later but the sense behind this would be what again?

Quote
SpaceX still has two DragonLab missions on the book (which I've been told they haven't given up on, yet), and they were planning to basically self-fund those. It'd make more sense to send one of them to Mars instead.
But cost much more money. New power supply, new electronics, new comms. And what communication network do they use back on earth to talk to that Dragon? DSN? Or do they build their own dishes? Another new development effort for high-power laser comm?
How do you navigate? Dragon uses GPS, last time I looked there was no GPS on the way to Mars.

I mean... LEO is sooooooo simple. All that infrastructure you use on earth still works there. Nothing of that will work on your way to Mars, you essentially start from scratch.

Quote
In spite of their early openness, SpaceX has several secret projects which they haven't publicized. They may have been working towards a 2018 mission for years.

Sure. And with their usual delay factor of 2.54 that would then mean then that they're going to launch some times in the early 30s....
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/09/2016 02:27 pm
Power and electronics are both sufficient, actually. Yup, they are. You get twice the sunlight in free space a you do in LEO, compensating for the fact that you're more distant. And the electronics have sufficient redundancy to work in the somewhat higher (but, let's be clear, NOT drastically higher) radiation environment of deep space, especially if they use the crewed variant which adds another whole string. Only comms would need updating. And they'll need to do that soon anyway. "Bag of stones" is ignorant hyperbole.

You will see Falcon Heavy soon, I will bet you money.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 03/09/2016 02:42 pm
And the electronics have sufficient redundancy to work in the somewhat higher (but, let's be clear, NOT drastically higher) radiation environment of deep space
Do you know that? Source? Or is this speculation?
It will also have to actually work independently for much longer than in LEO and in a colder environment.

Quote
You will see Falcon Heavy soon, I will bet you money.
How soon? What does "see" mean? Fly or just see? How much money? I don't believe we're going to see it fly in '16, I would not bet against it flying in '17.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/09/2016 03:02 pm
 Would you even take 2:1 odds against it flying in 2016? I think it has at least a 50:50 chance of flying this year, so I would definitely take the other side of that bet.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/09/2016 03:09 pm
And the electronics have sufficient redundancy to work in the somewhat higher (but, let's be clear, NOT drastically higher) radiation environment of deep space
Do you know that? Source? Or is this speculation?
It will also have to actually work independently for much longer than in LEO and in a colder environment.

...
Yes. Deep space is only about 2x the radiation of ISS, and Dragon has had few problems there. We have characterized the deep space radiation environment quite well, and Dragon is already capable of 2 year flights in LEO. Thermal control wouldn't be a challenge as Dragon already has the capability to actively moderate its thermal capability. Additionally, Dragon would not be shielded by the Earth half the time being in total darkness, so in some ways the thermal environment would be more benign (less hot and less cold!) for a trip to Mars than in LEO.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: raketa on 03/09/2016 03:19 pm
Reused Falcon Heavy flying a reused Dragon with a payload that they might be able to get NASA to pay for
Reused FH should be worth as much as a new one.
Reused Drageon: sure, or a used Ford Explorer or a bag of stones, doesn't matter if you want to throw dead weight towards Mars. Because that's what a "reused Dragon" would be once you leave LEO. No means of communication, electronics which probably won't survive the trip, too little power supply to work at Mars, no means of navigation...

And where's NASA's budget position for the payload, where is the payload (these things take time to develop) and then which payload do you want to fly on a dead spacecraft?

No, SpaceX is not going to Mars in '18.

Quote
And what makes you think they would start working on it /now/? If SpaceX is interested in 2018, they'd ALREADY have been working on this.
I have written that. It's the whole point of my argument: I think they are working on so many things in parallel that they have to prioritize and you can clearly see that FH is taking the hit in this, schedule wise. Now, of course you could prioritize a Mars payload at the expense of getting FH ready even later but the sense behind this would be what again?

Quote
SpaceX still has two DragonLab missions on the book (which I've been told they haven't given up on, yet), and they were planning to basically self-fund those. It'd make more sense to send one of them to Mars instead.
But cost much more money. New power supply, new electronics, new comms. And what communication network do they use back on earth to talk to that Dragon? DSN? Or do they build their own dishes? Another new development effort for high-power laser comm?
How do you navigate? Dragon uses GPS, last time I looked there was no GPS on the way to Mars.

I mean... LEO is sooooooo simple. All that infrastructure you use on earth still works there. Nothing of that will work on your way to Mars, you essentially start from scratch.

Quote
In spite of their early openness, SpaceX has several secret projects which they haven't publicized. They may have been working towards a 2018 mission for years.

Sure. And with their usual delay factor of 2.54 that would then mean then that they're going to launch some times in the early 30s....
Spacex is not NASA, they are working actually do something on Mars in near future. But they focus now on reusability. When it is  nailed done and lot spare first stages will be around, they will start test their hardware on Moon and every 2 years on Mars.
Their experience on power landing stages and Dragons give them heads up for some serious business and test on Moon and Mars and opportunity to start build supply pile on Mars.
It tooks them 12 years to perfect their launch system. I think it will take them less time to perfect their Mars launch systems.
I think 2024-2028 is reasonable time for their Mars landing.
But Falcon 9H could start to do initial test in 1-2 years on Moon or Mars. Think about modify falcon 9  second stage with legs could start to test landing on Moon pretty soon.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 03/09/2016 04:52 pm
Additionally, Dragon would not be shielded by the Earth half the time being in total darkness, so in some ways the thermal environment would be more benign (less hot and less cold!) for a trip to Mars than in LEO.
The earth still emits IR on the dark side which is quite significant an effect in LEO.

Radiation "only" about 2x higher and Dragon having "almost" no issues and _theoretically_ being able to work for an extended time all doesn't mean this is all going to have no effect and not being an issues. Reality has this nasty habit of showing you that your assumptions are wrong if you haven't designed/tested for a certain environment.

I'm not saying any of these deep-space issues are not solvable. It's just that this is not "just a re-used Dragon". This needs work.
Plus you didn't yet address the nav and comms issues. That, too, is all solved problems but it's again not "just a used Dragon", it's all new vehicle systems.
Let's remember it's not the empty pressure shell where all the money and development effort for a spacecraft goes.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 03/09/2016 04:58 pm
Spacex is not NASA, they are working actually do something on Mars in near future. But they focus now on reusability. When it is  nailed done and lot spare first stages will be around, they will start test their hardware on Moon and every 2 years on Mars.
Their experience on power landing stages and Dragons give them heads up for some serious business and test on Moon and Mars and opportunity to start build supply pile on Mars.
It tooks them 12 years to perfect their launch system. I think it will take them less time to perfect their Mars launch systems.
I think 2024-2028 is reasonable time for their Mars landing.
But Falcon 9H could start to do initial test in 1-2 years on Moon or Mars. Think about modify falcon 9  second stage with legs could start to test landing on Moon pretty soon.
Yes, of course NASA is just a bunch of stupid people who do all this stuff they do for no reason.
If you are as smart as SpaceX, rockets all of a sudden become LEGOs and you can "just" plug stuff together at will. Why did nobody else have that idea earlier. Must all these spaceflight people be dumb...

Look, SpaceX is smarter than that. They hava a long term vision to motivate themselves (go to Mars) but what they actually do and focus their efforts at is
#1 get government contracts and do whatever NASA and DOD needs right now.
#2 get comsat revenue
#3 get into the sat business

That's all pretty business oriented topics and it determines their short and medium term priorities. FH is relevant for a small part of that market and since it's easy enough to build it from what they have they will certainly do that. But it's share in what SpaceX actually does is small enough that it's not the highest of their priorities. Which is probably why it got delayed even more than everything else SpaceX does.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 03/09/2016 05:45 pm
SpaceX is not NASA, but they are not sitting on their hands blindly following customer contracts either.  Both NASA and SpaceX engage in R & D. The long term goal of SpaceX is BEO and what better way to test BEO systems than to launch some test missions.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 03/09/2016 06:12 pm
I see Falcon Heavy as using a used Falcon 9 core stage if they need to expend the core, and land the outer cores back at the launch site.  This would especially be true once they get used stages flying.  I can also see used stages with payloads of fuel or propellants, so that if there is a failure, it wouldn't be an expensive satellite or human cargo.  I think that is why Falcon Heavy will fly, not just for niche satellites to GSO, but to deliver large moon or Mars landers, and fuel to fuel depots.  Falcon 9 will launch most satellites and Dragon 2 with humans on new rockets, then the used rockets will roll over to Falcon Heavies mostly for fuel depot filling.  For a Falcon Heavy Mars expedition, they will have to have a fuel depot and a lot of fuel to fill the transfer, landing, and return crafts.  This could happen before BFR and MCT are built to test the scaled down equipment before final BFR and MCT are built and fine tuned. 

Also, moon, space stations at LEO or L1 can be built using Falcon Heavies and Bigelow modules.  So, maybe it is true, build it and they will come. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 03/09/2016 06:49 pm
Reused Falcon Heavy flying a reused Dragon with a payload that they might be able to get NASA to pay for
Reused FH should be worth as much as a new one.
Reused Drageon: sure, or a used Ford Explorer or a bag of stones, doesn't matter if you want to throw dead weight towards Mars. Because that's what a "reused Dragon" would be once you leave LEO. No means of communication, electronics which probably won't survive the trip, too little power supply to work at Mars, no means of navigation...

And where's NASA's budget position for the payload, where is the payload (these things take time to develop) and then which payload do you want to fly on a dead spacecraft?

No, SpaceX is not going to Mars in '18.

Quote
And what makes you think they would start working on it /now/? If SpaceX is interested in 2018, they'd ALREADY have been working on this.
I have written that. It's the whole point of my argument: I think they are working on so many things in parallel that they have to prioritize and you can clearly see that FH is taking the hit in this, schedule wise. Now, of course you could prioritize a Mars payload at the expense of getting FH ready even later but the sense behind this would be what again?

Quote
SpaceX still has two DragonLab missions on the book (which I've been told they haven't given up on, yet), and they were planning to basically self-fund those. It'd make more sense to send one of them to Mars instead.
But cost much more money. New power supply, new electronics, new comms. And what communication network do they use back on earth to talk to that Dragon? DSN? Or do they build their own dishes? Another new development effort for high-power laser comm?
How do you navigate? Dragon uses GPS, last time I looked there was no GPS on the way to Mars.

I mean... LEO is sooooooo simple. All that infrastructure you use on earth still works there. Nothing of that will work on your way to Mars, you essentially start from scratch.

Quote
In spite of their early openness, SpaceX has several secret projects which they haven't publicized. They may have been working towards a 2018 mission for years.

Sure. And with their usual delay factor of 2.54 that would then mean then that they're going to launch some times in the early 30s....

Where do you get this stuff?
Think you owe us a dozen or so IMOs. (IMHO)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 03/09/2016 07:21 pm
I simply want YOU to mark your opinion to market quantitatively.
80:20 for FH not successfully launching in 2016.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GWH on 03/09/2016 07:30 pm
I see Falcon Heavy as using a used Falcon 9 core stage if they need to expend the core, and land the outer cores back at the launch site. 

FYI the core of a FH isn't the same as a F9, I believe the primary difference is that it required additional reinforcement. 

Whether or not it would ever fly as a single stick for lighter payloads to amortize the cost before flying expendable is another matter, one that hasn't been hinted at in any way and isn't worth discussing at the moment IMO.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mme on 03/09/2016 09:35 pm
https://twitter.com/pbdes/status/707686842842353666 (https://twitter.com/pbdes/status/707686842842353666)
Quote
SpaceX's Shotwell: Falcon Heavy now expected to launch in November.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mader Levap on 03/09/2016 10:41 pm
Would you even take 2:1 odds against it flying in 2016? I think it has at least a 50:50 chance of flying this year, so I would definitely take the other side of that bet.
Currently it is slated to november 2016, according to SpaceX. It is their codeword for "middle of 2017".
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 03/09/2016 11:08 pm

Currently it is slated to november 2016, according to SpaceX. It is their codeword for "middle of 2017".

No it isn't, Mader. You don't work there, you don't know. Again, nobody has any incentive to lie in PR.

If it doesn't happen, it doesn't happen due to evolving circumstances. Until then, what they tell their customers is the most valid info we have on the subject. Anything beyond that is conspiracy mongering.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/09/2016 11:54 pm
Every thing is a "no earlier than" date. Assuming you have a distribution of possible launch dates, and the NET date provides one of the bounds to that distribution, then it seems pretty obvious to me that MOST launches will occur /after/ the given NET date, and there's nothing dishonest about that.

To be clear: That would be the case with or without SpaceX's usually optimistic projections.

I will admit that a November date causes me to do some Bayesian updating.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: stoker5432 on 03/10/2016 12:28 am
And the electronics have sufficient redundancy to work in the somewhat higher (but, let's be clear, NOT drastically higher) radiation environment of deep space
Do you know that? Source? Or is this speculation?
It will also have to actually work independently for much longer than in LEO and in a colder environment.

NASA and SpaceX figured out Dragon had "Sufficient lifetime & resources for Mars transfer trajectory" back in 2011.

http://digitalvideo.8m.net/SpaceX/RedDragon/karcz-red_dragon-nac-2011-10-29-1.pdf
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 03/10/2016 12:40 am

NASA and SpaceX figured out Dragon had "Sufficient lifetime & resources for Mars transfer trajectory" back in 2011.

http://digitalvideo.8m.net/SpaceX/RedDragon/karcz-red_dragon-nac-2011-10-29-1.pdf

Dragon had only flown one mission at the time.  So not a really a given or valid source.  And the "NASA" people in the study are not the agency experts nor even the agency regulars for spacecraft development.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: stoker5432 on 03/10/2016 12:42 am
Your welcome. I know Wikipedia is seen as an unreliable source, but there is entire page on Red Dragon with lots of NASA links.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 03/10/2016 12:44 am

NASA and SpaceX figured out Dragon had "Sufficient lifetime & resources for Mars transfer trajectory" back in 2011.

http://digitalvideo.8m.net/SpaceX/RedDragon/karcz-red_dragon-nac-2011-10-29-1.pdf

Dragon had only flown one mission at the time.  So not a really a given or valid source.

NASA is figuring out that Orion and SLS have sufficient capabilities for future missions and they haven't flown once.
Why is it that requires a number of flights before potential mission analysis?
What is a given or valid source?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 03/10/2016 12:56 am
Dragon had only flown one mission at the time.  So not a really a given or valid source.  And the "NASA" people in the study are not the agency experts nor even the agency regulars for spacecraft development.
And yet, this might be sufficient for SpaceX to think they could try it, whether it works or not.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 03/10/2016 12:59 am

NASA is figuring out that Orion and SLS have sufficient capabilities for future missions and they haven't flown once.


It is basic engineering.  One is designed for deep space missions and the other as in that paper was only designed for LEO missions.  They show no data in the paper to support their claims.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/10/2016 01:00 am
Right. The original thing I was contending was the idea that Dragon would be equivalent to a bag of stones (i.e. 100% probability of not working). While 5 sigma may or may not be guaranteed, it's certainly not guaranteed to fail, and there's good reason to believe Dragon has the resources to make a trip to Mars (other than some additions like deep space communications).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 03/10/2016 01:00 am

What is a given or valid source?

a NASA group that has designed and flown many spacecraft.  ARC is not that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: stoker5432 on 03/10/2016 01:10 am

What is a given or valid source?

a NASA group that has designed and flown many spacecraft.  ARC is not that.

JPL thought it was a viable concept in 2012. Haven't seen anything changing their position. Have you?

http://www.lpi.usra.edu/meetings/marsconcepts2012/pdf/4216.pdf
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 03/10/2016 01:46 am
I simply want YOU to mark your opinion to market quantitatively.
80:20 for FH not successfully launching in 2016.

Pippin, I was happy to let your concern trolling[1] just roll on by, but then you had to go and use the adjective LEGO in a sentence incorrectly. ("rockets all of a sudden become LEGOs ") Those are fighting words...

I'll take the other side of that bet, PM me with what currency you want to use. Ten dollars of LEGO elements against 40, perhaps? A six pack against a case? Or admit that it's idle talk and you're not willing to put up....

1 - that's how it reads to me anyway...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: stoker5432 on 03/10/2016 04:19 am

NASA and SpaceX figured out Dragon had "Sufficient lifetime & resources for Mars transfer trajectory" back in 2011.

http://digitalvideo.8m.net/SpaceX/RedDragon/karcz-red_dragon-nac-2011-10-29-1.pdf

Dragon had only flown one mission at the time.  So not a really a given or valid source.  And the "NASA" people in the study are not the agency experts nor even the agency regulars for spacecraft development.

So we're going on five years and not one valid source that I can find has disputed JPL's, ARC's, or SpaceX's findings. In fact there's been even more research saying it will work. You've been giving the same argument since 2011. Seems like you should be able to give some solid info by now to prove them wrong.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 03/10/2016 04:30 am

So we're going on five years and not one valid source that I can find has disputed JPL's, ARC's, or SpaceX's findings. In fact there's been even more research saying it will work. You've been giving the same argument since 2011. Seems like you should be able to give some solid info by now to prove them wrong.

What "more" research?   You keep referring to the same two papers over and over.  Spacex has been modifying their vehicles between each flight.    The Dragon (and Falcon for that matter too) referred too in those papers doesn't exist anymore.  So how could the concept have worked?  They had no idea of the changes needed?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dorkmo on 03/10/2016 04:57 am
Since i love everybody, i feel like i should step in here and say we're talking about deep space design on the dragon in a falcon heavy discussion, wich should probably be in the spacex mars section. and that while both sides have valid points, we do not have hard evidence either way what the most current dragon is capable of.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: stoker5432 on 03/10/2016 05:36 am
SpaceX has already said they plan to send Dragons to Mars with Falcon Heavy. Why would they launch a payload that's not capable of getting to its destination and waste a FH? Sure arguing about the time table seems logical, but doubting the capability of the payload, at least on this thread, doesn't.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dorkmo on 03/10/2016 05:47 am
SpaceX has already said they plan to send Dragons to Mars with Falcon Heavy. Why would they launch a payload that's not capable of getting to its destination and waste a FH? Sure arguing about the time table seems logical, but doubting the capability of the payload, at least on this thread, doesn't.

I believe whatever design they end up launching to mars has a very good chance of having no problems. but being fair to jim there doesnt appear to have been an exhaustive study or critical design review type process to validate the original dragon for anything beyond LEO.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/10/2016 06:04 am
We're talking about a CDR, now?? That's how far the goalposts have moved?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mader Levap on 03/10/2016 12:01 pm
Again, nobody has any incentive to lie in PR.
So what? They stated date of first FH launch multiple times. Each time it was replaced with new date. I do not see any reason to believe they will actually launch in nov 2016. I will believe that we start to get closer when their slips will be less than elapsed time. So far every 6 months it slips by 6 months.

To be clear, "their codeword" phrase was my sarcasm, not accusation of deliberate lie.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 03/10/2016 12:22 pm
I simply want YOU to mark your opinion to market quantitatively.
80:20 for FH not successfully launching in 2016.

Pippin, I was happy to let your concern trolling[1] just roll on by, but then you had to go and use the adjective LEGO in a sentence incorrectly. ("rockets all of a sudden become LEGOs ") Those are fighting words...

I'll take the other side of that bet, PM me with what currency you want to use. Ten dollars of LEGO elements against 40, perhaps? A six pack against a case? Or admit that it's idle talk and you're not willing to put up....

1 - that's how it reads to me anyway...

Well, me believing in an 80:20 chance of FH not flying this year doesn't mean I'd bet at that quota, no sense in betting if your expected return is zero. You bet if both sides estimates differ in a way that both sides of spect to win, not one side expecting to even out.

But since I'm pretty convinced I'd byte at 2:1 so I'd offer a 20$ bag of LEGOs against your 10$ bag of LEGOs (or whatever useful $10 packs these bricks come in)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Johnnyhinbos on 03/10/2016 04:04 pm
Any thoughts on what the side booster separation mechanism is going to be on the FH? With SpaceX's fondness for pneumatic systems over explosive ones I was curious what folks thought. I can't imagine it would be anything other than explosive, but I don't think SpaceX has a ton of experience in that front.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 03/10/2016 04:27 pm
Any thoughts on what the side booster separation mechanism is going to be on the FH? With SpaceX's fondness for pneumatic systems over explosive ones I was curious what folks thought. I can't imagine it would be anything other than explosive, but I don't think SpaceX has a ton of experience in that front.

What about pneumatic at the connectors and cold gas thrusters at the top to ensure that the tops of side boosters are moving away from the centre core. note that the centre core's engines will not be shut down for separation and from a practical point of view while I think the side boosters must shutdown at or just before separation, if something happened that they didn't shut down, I think having the top of the booster thrust away from the centre core simply makes sense.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/10/2016 04:46 pm
No way SpaceX would use explosive separation as the nominal separation method. See the latest Falcon Heavy video.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: matthewkantar on 03/11/2016 06:15 pm
I hope this isn't the wrong thread for this, Instagram post may show Falcon Heavy nose cone! Sloppy paint?

Enjoy, Matthew

Edit, What is the large straight barrel next to it? Composite interstage? Seems too long.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: russianhalo117 on 03/11/2016 06:29 pm
I hope this isn't the wrong thread for this, Instagram post may show Falcon Heavy nose cone! Sloppy paint?

Enjoy, Matthew

Edit, What is the large straight barrel next to it? Composite interstage? Seems too long.

Composite Interstage is likely yes as there are more behind it and the interstage in some graphics in the last year show it a bit longer for FH than F9.
Now if this is for the demo flight it could also be the dummy payload SpaceX is flying on first flight, but I haven't yet seen any info/pictures confirming that theory.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/11/2016 06:29 pm
Source?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 03/11/2016 06:29 pm
Nice!
Looks like two fairing sizes, too, unless it is just the view angle.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: OnWithTheShow on 03/11/2016 06:33 pm
Source?

SpaceX posted it on their Facebook page.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: matthewkantar on 03/11/2016 06:35 pm
So much in this picture. I think the fairing section in the foreground is above a robot on a track, perhaps for installing the insulation panels? Eutelsat-117 fairing painted and ready to go in the background. I think the fairing halves are the same size, one is just closer to the camera, and higher off the ground.

Enjoy, Matthew
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 03/11/2016 06:38 pm
Could be the perspective and/or a wide angle lens. Maybe my old eyes. ISTR we've heard rumors of a longer fairing for Bigelow habs, but ISTM some military birds may need one too. Any input Jim?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Craftyatom on 03/12/2016 03:17 am
The painted interstage that's horizontal behind the unpainted one has obvious holes for grid fins.  Not sure if I'm just not seeing the holes on the unpainted one, if the holes are added later in the process (seems unlikely but composites are not my strong point), or if maybe this new interstage is for a core that won't be equipped with fins.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 03/12/2016 09:58 am
So much in this picture. I think the fairing section in the foreground is above a robot on a track, perhaps for installing the insulation panels?

How about just for trimming the edges.  Insulation is installed at the launch site.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 03/12/2016 09:59 am
Could be the perspective and/or a wide angle lens. Maybe my old eyes. ISTR we've heard rumors of a longer fairing for Bigelow habs, but ISTM some military birds may need one too. Any input Jim?

I think it is just camera perspective.  There is only one length.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: obi-wan on 03/12/2016 02:35 pm
So much in this picture. I think the fairing section in the foreground is above a robot on a track, perhaps for installing the insulation panels?

How about just for trimming the edges.  Insulation is installed at the launch site.

It's actually an inspection system - there's a large C-shaped fixture on the end of an industrial robot arm that scans the entire surface of the fairing, most likely looking for internal delaminations.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AndersofOz on 03/13/2016 01:17 am
Article in the Register citing Gwynn Shotwell saying the FH launch will be in November.

There is also some interesting information on reuse costs.

http://www.theregister.co.uk/2016/03/11/spacex_first_falcon_heavy_liftoff/
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RyanC on 03/13/2016 03:37 pm
Nobody has any proof that they're deliberately flat-out delaying. More likely that they keep iterating upgrades which cause them to change FH's design slightly, but the pressure is on now. It will fly this year.

IMHO, 2016 is the critical year for Falcon Heavy for SpaceX. ED: They essentially need to get a complete set of flight hardware out the door by 31 Dec 2016.

The international launch market is not like the market for Virgin Galactic's SS2.

VG's market is basically really rich people who can afford to plop down $250K and have it tied up for most of a decade, and then hire decent lawyers to get *most* of it back if they ask for a refund.

Basically, the same guys who can afford to buy $745,000 to $1.5 million USD boats and then use them a few days each year.

By contrast (forgive me for a quick and dirty wiki-ing spree); the international launch market as presently configured is a lot more inflexible; satellites that sit on the ground due to delays (Proton/Briz-M failures, etc) cost the owner a lot of money each year to maintain them in flight-ready condition.

With only 20 to 30 launches a year and lead times of 36 months (3 years) for GEO launches (based upon INMARSAT-5 series, where the satellites were ordered August 2010, Launch provider contracted August 2011 and the first mission flown August 2013); the games that Virgin Galactic and to a lesser extent SpaceX is doing with Elon Time [tm] aren't capable of being sustained like they are in the tourism market.

Following is my speculation:

The vendors are willing to accomodate delays from new entrants into the market and from existing companies in order to retire risk, as a failed launch can cause significant delays of up to 24+ months in launch campaigns; costing them a lot of money.

With that said, the vendors are constrained by their existing satellite constellations aging out and business plans for expansion through more satellites; so they can't wait forever for the launch providers to be ready.

INMARSAT's booking of the Proton for Europasat/Hellas-sat 3 as a backup to Falcon Heavy is essentially the closest you're going to get to a public message to SpaceX to stop getting diverted by various items (Falcon 9 Recovery, Raptor, Dragon 2, MCT) and put manpower into Falcon Heavy to bring 'Elon Time' closer to real time.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/13/2016 04:28 pm
The delays to Falcon Heavy and Falcon 9 meant enormous upgrades to Falcon 9 (and ultimately Falcon Heavy). Nearly all of the GEO birds launched by Falcon 9 so far would've needed a Falcon Heavy if SpaceX had skipped Merlin 1D and v1.1 and full thrust, etc.... Falcon 9 full thrust expendable gets about 60-75% of the payload to GTO as the original Falcon 9 Heavy would've.

But anyway, Falcon Heavy will definitely be "out the door" of Hawthorne by the end of this year. Actually MUCH earlier than that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 03/13/2016 04:32 pm
Nobody has any proof that they're deliberately flat-out delaying. More likely that they keep iterating upgrades which cause them to change FH's design slightly, but the pressure is on now. It will fly this year.

IMHO, 2016 is the critical year for Falcon Heavy for SpaceX. ED: They essentially need to get a complete set of flight hardware out the door by 31 Dec 2016.

That's not saying much. EVERY YEAR is a critical year for SpaceX.

And even more critically for people on this forum, it seems.  People said it about 2015. (and before) And the same will be written about 2017. :P
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RocketmanUS on 03/13/2016 05:12 pm
Article in the Register citing Gwynn Shotwell saying the FH launch will be in November.

There is also some interesting information on reuse costs.

http://www.theregister.co.uk/2016/03/11/spacex_first_falcon_heavy_liftoff/
So from that article would a core cost about $20M?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/13/2016 11:11 pm
Article in the Register citing Gwynn Shotwell saying the FH launch will be in November.

There is also some interesting information on reuse costs.

http://www.theregister.co.uk/2016/03/11/spacex_first_falcon_heavy_liftoff/
So from that article would a core cost about $20M?
Not that simple.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RocketmanUS on 03/13/2016 11:26 pm
Article in the Register citing Gwynn Shotwell saying the FH launch will be in November.

There is also some interesting information on reuse costs.

http://www.theregister.co.uk/2016/03/11/spacex_first_falcon_heavy_liftoff/
So from that article would a core cost about $20M?
Not that simple.
I don't think they would be cutting into their profit on a first reuse flight.
What is your estimate for a core stage?
What do you estimate from the info on the article for reuse cost?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 03/14/2016 12:10 am
Article in the Register citing Gwynn Shotwell saying the FH launch will be in November.

There is also some interesting information on reuse costs.

http://www.theregister.co.uk/2016/03/11/spacex_first_falcon_heavy_liftoff/
So from that article would a core cost about $20M?
Not that simple.
I don't think they would be cutting into their profit on a first reuse flight.
What is your estimate for a core stage?
What do you estimate from the info on the article for reuse cost?
The equation goes something like this:

[Cost of a new 1st stage] - $3M[the refurbishment costs] = [The cost savings/price reduction per flight before profit add on]

If profit is 20% which is fairly standard in the LV providers business, then the cost of the 1st stage is $19M. This is because the profit associated with dropping the price $20M is $4M leaving a cost before profit reduction of $16M. Add the $3M refurbishment costs and that gets you $19M. If profit is 10% then the profit associated with the $20M price reduction is $2M so $18M + the $3M yeilds a stage cost of $21M.

So yes about $20M for a 1st stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/14/2016 02:25 am
Except maybe they keep profit constant (not relative, i.e. 20%), or even increase profit in order to "pay back" all that money they spent getting the bugs out of reusability. I mean, how many parachutes, legs, and fins did they dump into the ocean trying to get all this to work? They can use that extra money to pay for their next reusability project, which is the upper stage, which will be a lot harder.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: intrepidpursuit on 03/14/2016 02:31 am
Except maybe they keep profit constant (not relative, i.e. 20%), or even increase profit in order to "pay back" all that money they spent getting the bugs out of reusability. I mean, how many parachutes, legs, and fins did they dump into the ocean trying to get all this to work? They can use that extra money to pay for their next reusability project, which is the upper stage, which will be a lot harder.

Exactly. When a manufacturer finds a cheaper way to do something there is no obligation not to just keep the extra profit. If it is something that make a product obviously cheaper, then maybe they reduce the price due to the perceived reduction in value, but even then it should be for higher overall profit. If you cut manufacturing costs 20% and then reduce your price 20% you just lowered your profit for no reason.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mike_1179 on 03/14/2016 11:49 am

If you cut manufacturing costs 20% and then reduce your price 20% you just lowered your profit for no reason.

Unless you're trying to gain market share from competition. The expectation is that at some point in the future, when you have more customers since you gained share, you then increase price to reap the benefit. But this isn't a normal business.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RyanC on 03/14/2016 07:14 pm
That's not saying much. EVERY YEAR is a critical year for SpaceX.

Well, maybe I was prone to some hyperbole; but this year is critical to their long term plans.

If they want to break into the lucrative heavy commercial GEO market as well as the mega-lucrative DOD market to fund their future mars ambitions (MCT, Raptor, etc); FH needs to come out sometime this year (*) to:

A.) reassure the early customers of FH that yes, this is coming. There's already some sign of shakiness with one FH initial mission being rebooked to a different provider and another mission acquiring a backup Plan B.

B.) Put something concrete out there so that operators can be reassured that FH will be operational approximately 36~ months from now so they can start being serious about signing launch contracts for that period -- providing SpX with cash inflows and prestige.

C.) Start gaining flight experience with FH in order to be ready for the GPS 3 launch in 2018 and thus opening up the DOD Market.

(* -- Rollout, not actual launch. The actual launch can slip into early winter 2017, due to unforeseen difficulties without ill effects).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 03/15/2016 01:01 am
That's not saying much. EVERY YEAR is a critical year for SpaceX.

Well, maybe I was prone to some hyperbole; but this year is critical to their long term plans.

If they want to break into the lucrative heavy commercial GEO market as well as the mega-lucrative DOD market to fund their future mars ambitions (MCT, Raptor, etc); FH needs to come out sometime this year (*) to:
...[snip]...
(* -- Rollout, not actual launch. The actual launch can slip into early winter 2017, due to unforeseen difficulties without ill effects).

But it still is a meaningless statement. If they fail to get FH out this year, 2017 will be even more critical. And so on. None of your supporting arguments are limited to this year only.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 03/15/2016 03:27 am
Here's a quote being attributed to Gwen Shotwell at Jeff Foust's site regarding FH:
http://thespacereview.com/article/2943/1 (http://thespacereview.com/article/2943/1)

“The Falcon Heavy is delayed, but we haven’t disappointed any customers yet on that,”

I don't seem much positive in this statement.  It is primarily a tacit recognition of the low priority FH has not only by SpaceX, but also to potential customers.   The fact that they communicate to the SpaceX president that FH delays are of no concern to them implies that they don't plan on buying the rocket, or that any contracts are sufficiently far enough into the future that current delays don't matter.

Either way, the end result is likely to be that FH will rarely, if ever fly. Maybe I'm being overly skeptical, but when your customers don't care about your product that is delayed some 3 years, what does it really mean?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RocketGoBoom on 03/15/2016 05:19 am

Either way, the end result is likely to be that FH will rarely, if ever fly. Maybe I'm being overly skeptical, but when your customers don't care about your product that is delayed some 3 years, what does it really mean?

Delta Heavy averages less than 1 launch per year.

There are not many payloads that even need the Delta Heavy lift capacity.

So everyone that is a possible customer for Falcon Heavy is thrilled that there is even a new option coming at any point in the future. This is a rare beast that is being created.

Everyone in the market understands the complexity of what is being done here.
They care, but they also get it.

Let's face it, anyone that signs a contract for a rocket that has never flown has to have some reasonable expectations that it ain't going to be on schedule. That has to be the most speculative contract possible in this business, especially with Elon.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 03/15/2016 05:39 am
It is primarily a tacit recognition of the low priority FH has not only by SpaceX, but also to potential customers.

It has not been a higher priority than Falcon 9, which it is based on.  That is true.

Quote
Maybe I'm being overly skeptical, but when your customers don't care about your product that is delayed some 3 years, what does it really mean?

That they didn't need the Falcon Heavy yet?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 03/15/2016 06:05 am

Either way, the end result is likely to be that FH will rarely, if ever fly. Maybe I'm being overly skeptical, but when your customers don't care about your product that is delayed some 3 years, what does it really mean?

Delta Heavy averages less than 1 launch per year.

There are not many payloads that even need the Delta Heavy lift capacity.

The main competition is Ariane V, (and mabe also heavier models of atlas v), not so much delta iv.

For example, during 2016 Ariane V has launched EUtelsat 65 west a and intelsat 29.  At about 6.5 tonnes weight Ariane V was the cheapest launcher that could launch them(only other available options being delta ivh, atlas v with at last 3 SRBs and H-IIB, they were too heavy even for proton), and F-H will be cheaper than any of these. (though a future version of F9 with expendable methane upper stage could propably also launch them, but that will be many years later than F-H).

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jet Black on 03/15/2016 09:32 am
Here's a quote being attributed to Gwen Shotwell at Jeff Foust's site regarding FH:
http://thespacereview.com/article/2943/1 (http://thespacereview.com/article/2943/1)

“The Falcon Heavy is delayed, but we haven’t disappointed any customers yet on that,”

I don't seem much positive in this statement.  It is primarily a tacit recognition of the low priority FH has not only by SpaceX, but also to potential customers.   The fact that they communicate to the SpaceX president that FH delays are of no concern to them implies that they don't plan on buying the rocket, or that any contracts are sufficiently far enough into the future that current delays don't matter.

Either way, the end result is likely to be that FH will rarely, if ever fly. Maybe I'm being overly skeptical, but when your customers don't care about your product that is delayed some 3 years, what does it really mean?

Not necessarily. It may well allow some customers that would be forced to operate in expendable mode to operate in a reuse mode, reducing costs. I doubt any customers are yet factoring the reduced costs of reuse into their financial calculations. Additionally the market may be there, but either currently served by other launchers or alternatively it might be a market in waiting, because there are no suitable launchers yet (in terms of weight and cost)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/15/2016 11:31 am
Falcon 9 Full Thrust can launch ~60-75% of the payload of the original Falcon 9 S9 Heavy and double the original Falcon 9 when first announced. That means that most of the payloads that would've required a Heavy now can be launched on Falcon 9, and if you sacrifice a few months to boosting using SEP, even more satellites fit on Falcon 9.

However, it's false to conclude Falcon Heavy will never fly or only do so rarely.

The delay to Falcon Heavy is kind of good, since it allows the performance and reliability of Merlin and the stages to be improved to the point that now we can expect fairly good reliability in spite of all those engines and stages.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 03/15/2016 11:57 am
Falcon 9 Full Thrust can launch ~60-75% of the payload of the original Falcon 9 S9 Heavy and double the original Falcon 9 when first announced. That means that most of the payloads that would've required a Heavy now can be launched on Falcon 9, and if you sacrifice a few months to boosting using SEP, even more satellites fit on Falcon 9.

However, it's false to conclude Falcon Heavy will never fly or only do so rarely.

The delay to Falcon Heavy is kind of good, since it allows the performance and reliability of Merlin and the stages to be improved to the point that now we can expect fairly good reliability in spite of all those engines and stages.

Coupled to that, it means the heavy in full thrust iteration will be a considerably more formidable rocket than it's original incarnation as well. Sure, it's not a superheavy LV, but it's an intermediary between SLS/BFR/Saturn/Energia range and every other payload range out there, and a considerably less expensive alternative to any of the listed heavy LVs.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RDoc on 03/15/2016 12:22 pm
As has been mentioned before, the real point to FH may be reuse, in particular second stage and fairing reuse. The extra performance may also help with the first stages' recovery since it potentially makes more fuel available for landing.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 03/15/2016 01:23 pm
Falcon 9 Full Thrust can launch ~60-75% of the payload of the original Falcon 9 S9 Heavy and double the original Falcon 9 when first announced. That means that most of the payloads that would've required a Heavy now can be launched on Falcon 9, and if you sacrifice a few months to boosting using SEP, even more satellites fit on Falcon 9.

However, it's false to conclude Falcon Heavy will never fly or only do so rarely.

The delay to Falcon Heavy is kind of good, since it allows the performance and reliability of Merlin and the stages to be improved to the point that now we can expect fairly good reliability in spite of all those engines and stages.

Coupled to that, it means the heavy in full thrust iteration will be a considerably more formidable rocket than it's original incarnation as well. Sure, it's not a superheavy LV, but it's an intermediary between SLS/BFR/Saturn/Energia range and every other payload range out there, and a considerably less expensive alternative to any of the listed heavy LVs.

I thought super-heavy was defined as greater than 50 tonnes to LEO (assuming expendable).  Some calculations show FH at greater than 70 tonnes to LEO, expendable.  It is still a heavy when three cores are recovered if heavy is defined as 20-50 tonnes.  (F9 FT is also a heavy lift vehicle by this definition.)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: drzerg on 03/15/2016 06:31 pm
what payload is planned for first heavy? or just waste 50t to leo?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 03/15/2016 06:49 pm

I thought super-heavy was defined as greater than 50 tonnes to LEO (assuming expendable).  Some calculations show FH at greater than 70 tonnes to LEO, expendable.  It is still a heavy when three cores are recovered if heavy is defined as 20-50 tonnes.  (F9 FT is also a heavy lift vehicle by this definition.)

Definition is sketchy at best according to the uses I've seen here (somebody who knows better please correct me). I'm not even sure if there is an industry standard for this weight class.

Since I imagine F9HR is the primary iteration we're going to see the heavy take, I'm using its theoretical maximum for three core recovery, not expendable.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 03/15/2016 07:00 pm
Falcon 9 Full Thrust can launch ~60-75% of the payload of the original Falcon 9 S9 Heavy and double the original Falcon 9 when first announced. That means that most of the payloads that would've required a Heavy now can be launched on Falcon 9, and if you sacrifice a few months to boosting using SEP, even more satellites fit on Falcon 9.

However, it's false to conclude Falcon Heavy will never fly or only do so rarely.

The delay to Falcon Heavy is kind of good, since it allows the performance and reliability of Merlin and the stages to be improved to the point that now we can expect fairly good reliability in spite of all those engines and stages.

Coupled to that, it means the heavy in full thrust iteration will be a considerably more formidable rocket than it's original incarnation as well. Sure, it's not a superheavy LV, but it's an intermediary between SLS/BFR/Saturn/Energia range and every other payload range out there, and a considerably less expensive alternative to any of the listed heavy LVs.

I thought super-heavy was defined as greater than 50 tonnes to LEO (assuming expendable).  Some calculations show FH at greater than 70 tonnes to LEO, expendable.

These calculations were based on broken assumptions and/or version of FH that will not materialize(cross-feed)

Quote
It is still a heavy when three cores are recovered if heavy is defined as 20-50 tonnes.  (F9 FT is also a heavy lift vehicle by this definition.)

No it's not, it cannot lift 20 tonnes to LEO.

And the original definition of Heavy was much more than 20 tonnes, the definition has changed (when the EELV's came?)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: OnWithTheShow on 03/15/2016 09:55 pm
Quote
No it's not, it cannot lift 20 tonnes to LEO.

You really dont think a 3 core recovery FH wont be able to lift 20 mt to LEO?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LastStarFighter on 03/15/2016 10:17 pm
Quote
No it's not, it cannot lift 20 tonnes to LEO.

You really dont think a 3 core recovery FH wont be able to lift 20 mt to LEO?

I beleive the "no it's not" was in response to the F9FT being also considered a "heavy" launcher. Not disputing the FHR would be able to do 20t
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: matthewkantar on 03/15/2016 10:23 pm
Spacex's web site gives 10,692 pounds to Geo, recently did 11,596 pounds with a landing attempt. Same page gives 28,991 pounds to LEO.

Matthew

Edit: These figures are for Falcon-9
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Herb Schaltegger on 03/15/2016 10:32 pm
Spacex's web site gives 10,692 pounds to Geo, recently did 11,596 pounds with a landing attempt. Same page gives 28,991 pounds to LEO.

Right. Which is substantially less than 20 metric tons.

(I presume you are referring to F9FT, not FH - you didn't specify.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/15/2016 10:45 pm
Falcon 9 Full Thrust can launch ~60-75% of the payload of the original Falcon 9 S9 Heavy and double the original Falcon 9 when first announced. That means that most of the payloads that would've required a Heavy now can be launched on Falcon 9, and if you sacrifice a few months to boosting using SEP, even more satellites fit on Falcon 9.

However, it's false to conclude Falcon Heavy will never fly or only do so rarely.

The delay to Falcon Heavy is kind of good, since it allows the performance and reliability of Merlin and the stages to be improved to the point that now we can expect fairly good reliability in spite of all those engines and stages.

Coupled to that, it means the heavy in full thrust iteration will be a considerably more formidable rocket than it's original incarnation as well. Sure, it's not a superheavy LV, but it's an intermediary between SLS/BFR/Saturn/Energia range and every other payload range out there, and a considerably less expensive alternative to any of the listed heavy LVs.

I thought super-heavy was defined as greater than 50 tonnes to LEO (assuming expendable).  Some calculations show FH at greater than 70 tonnes to LEO, expendable.

These calculations were based on broken assumptions and/or version of FH that will not materialize(cross-feed)
A few things in here are false. No one has said crossfeed WON'T happen, just that it has been delayed and densification and full thrust make it unnecessary to achieve the necessary performance. Shotwell said it'd be needed if you need like a 60 ton payload. It is most definitely still on the table.

The 70 tons may also need a Raptor upper stage.

In any case, even the 53 ton Falcon Heavy performance is in excess of Shuttle C Phase I.
Quote
Quote
It is still a heavy when three cores are recovered if heavy is defined as 20-50 tonnes.  (F9 FT is also a heavy lift vehicle by this definition.)

No it's not, it cannot lift 20 tonnes to LEO.
It may, in full thrust mode to low inclination and altitude. With Raptor upper stage it almost certainly can. Heck, if fully expendable with Raptor upper stage, it probably can do the 25 tons that the original Falcon 9 S9 Heavy was slated for.

Quote
And the original definition of Heavy was much more than 20 tonnes, the definition has changed (when the EELV's came?)
Proton, Titan IV H, etc were also considered heavy. Maybe even Saturn IB. Saturn V is super heavy.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 03/15/2016 10:51 pm
Spacex's web site gives 10,692 pounds to Geo, recently did 11,596 pounds with a landing attempt. Same page gives 28,991 pounds to LEO.

Right. Which is substantially less than 20 metric tons.

(I presume you are referring to F9FT, not FH - you didn't specify.
Wooosh!

His point was that the SpaceX page info (which gives substantially less than 20 tons) is significantly sandbagged.

For example, http://elvperf.ksc.nasa.gov/ gives v1.1 performance ("believed to be conservative", and includes weight of the fairing and launch from LC-40... from Texas would have slightly more performance) of 16,625kg to 200km and 28.5 degrees. If Full thrust gets 20% more performance, then you're talking 20 metric tons. Most certainly with Raptor. Either way, it's quite close to 20 tons.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: OxCartMark on 03/18/2016 02:49 am
NASA Tech Briefs: Autonomous Flight Termination System

We all know that autonomous flight termination systems are coming.  This link gives some information (though mostly informationless information).  I couldn't find a more reasonable place in NSF to post this.  Putting it here because the article states "AFTS is necessary to support vehicles that have multiple flyback boosters."  I sat back a while and thought through how many vehicles I was aware of that have multiply flyback boosters and came to the conclusion to post here.

http://www.techbriefs.com/component/content/article/8-ntb/tech-briefs/machinery-and-automation/24084-ksc-13978


Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 03/18/2016 03:25 am
NASA Tech Briefs: Autonomous Flight Termination System

We all know that autonomous flight termination systems are coming.  This link gives some information (though mostly informationless information).  I couldn't find a more reasonable place in NSF to post this.  Putting it here because the article states "AFTS is necessary to support vehicles that have multiple flyback boosters."  I sat back a while and thought through how many vehicles I was aware of that have multiply flyback boosters and came to the conclusion to post here.

http://www.techbriefs.com/component/content/article/8-ntb/tech-briefs/machinery-and-automation/24084-ksc-13978

Good find. You might want to post a link in this thread too:

https://forum.nasaspaceflight.com/index.php?topic=35431.220
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: IntoTheVoid on 03/18/2016 04:06 pm
NASA Tech Briefs: Autonomous Flight Termination System

We all know that autonomous flight termination systems are coming.  This link gives some information (though mostly informationless information).  I couldn't find a more reasonable place in NSF to post this.  Putting it here because the article states "AFTS is necessary to support vehicles that have multiple flyback boosters."  I sat back a while and thought through how many vehicles I was aware of that have multiply flyback boosters and came to the conclusion to post here.

http://www.techbriefs.com/component/content/article/8-ntb/tech-briefs/machinery-and-automation/24084-ksc-13978

Slide 11, from the NASA brief below, says that they have it, or at least strongly implies that they will.

In-flight abort test appears to be currently planned around March 2017. See slide 6:

http://www.nasa.gov/sites/default/files/files/4-CCP-Status-McAlister.pdf
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mike Jones on 03/28/2016 12:34 pm
According to P. De Selding (Spacenews):
ViaSat, Ex-Im Bank reduce $524.9M ViaSat-2 loan to $386.7M, reflecting Launch shift from SpaceX (US) to Arianespace (France/Europe).

Does that mean that a Falcon Heavy launch cost ~138 M$ on the commercial market for xL payloads like Viasat 2 ? It would mean that Falcon Heavy is super expensive compared to Proton and to a lesser degree Ariane 5 in upper position ! Difficult to imagine more than 1 Falcon Heavy commercial launch pre year with such pricing ....
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dorkmo on 03/28/2016 02:13 pm
According to P. De Selding (Spacenews):
ViaSat, Ex-Im Bank reduce $524.9M ViaSat-2 loan to $386.7M, reflecting Launch shift from SpaceX (US) to Arianespace (France/Europe).

Does that mean that a Falcon Heavy launch cost ~138 M$ on the commercial market for xL payloads like Viasat 2 ? It would mean that Falcon Heavy is super expensive compared to Proton and to a lesser degree Ariane 5 in upper position ! Difficult to imagine more than 1 Falcon Heavy commercial launch pre year with such pricing ....

how much does insurance usually cost, perhaps more for an new rocket class? would the bank put up money for that? then probably some small processing and handling charges? 138 is pretty far off from list price of 90.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cletus on 03/28/2016 09:09 pm
Any speculation on the black and white striped nosecone-looking object in the back left of SpaceX's most recent Instagram picture https://www.instagram.com/p/BDgfxVeF8TW/ (https://www.instagram.com/p/BDgfxVeF8TW/)? Falcon Heavy, maybe?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: russianhalo117 on 03/28/2016 09:27 pm
Any speculation on the black and white striped nosecone-looking object in the back left of SpaceX's most recent Instagram picture https://www.instagram.com/p/BDgfxVeF8TW/ (https://www.instagram.com/p/BDgfxVeF8TW/)? Falcon Heavy, maybe?
This has been discussed earlier in this thread. Please look back for answer
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 03/29/2016 04:29 pm
Trying to understand how this integrated, interdependent yet autonomous reusable system is programmed:

Does the center core monitor and control both boosters up until booster separation where each booster is then autonomous for RTLS?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 03/29/2016 04:38 pm
Trying to understand how this integrated, interdependent yet autonomous reusable system is programmed:

Does the center core monitor and control both boosters up until booster separation where each booster is then autonomous for RTLS?

Upperstage controls the stack until separation, just like the basic F9.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LastStarFighter on 03/29/2016 05:23 pm
According to P. De Selding (Spacenews):
ViaSat, Ex-Im Bank reduce $524.9M ViaSat-2 loan to $386.7M, reflecting Launch shift from SpaceX (US) to Arianespace (France/Europe).

Does that mean that a Falcon Heavy launch cost ~138 M$ on the commercial market for xL payloads like Viasat 2 ? It would mean that Falcon Heavy is super expensive compared to Proton and to a lesser degree Ariane 5 in upper position ! Difficult to imagine more than 1 Falcon Heavy commercial launch pre year with such pricing ....

Why would the loan go down when switching to Ariane?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 03/29/2016 05:33 pm
The American export-import bank only provides loans to buy/sell from US companies.  It is an instrument of trade policy, helps American businesses abroad.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LastStarFighter on 03/29/2016 07:00 pm
The American export-import bank only provides loans to buy/sell from US companies.  It is an instrument of trade policy, helps American businesses abroad.

That's right. I forgot Boeing was building it. Thanks for the wake up
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 04/01/2016 07:25 pm
Sea Launch has finally been sold. What are the odds SpaceX bought it for the Odyssey platform, to park it downrange of Boca Chica as a fixed "base" for core landings?

http://www.themoscowtimes.com/news/article/roscosmos-sells-troubled-commercial-space-company-sea-launch/564042.html

Odyssey has been parked in Long Beach, not far from SpaceX HQ. That's got to have put ideas in some people's heads...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: M_Puckett on 04/01/2016 07:39 pm
For a landing pad???


https://www.youtube.com/watch?v=3VNUyjRRjxM (https://www.youtube.com/watch?v=3VNUyjRRjxM)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Ronsmytheiii on 04/01/2016 07:39 pm
According to P. De Selding (Spacenews):
ViaSat, Ex-Im Bank reduce $524.9M ViaSat-2 loan to $386.7M, reflecting Launch shift from SpaceX (US) to Arianespace (France/Europe).

Does that mean that a Falcon Heavy launch cost ~138 M$ on the commercial market for xL payloads like Viasat 2 ? It would mean that Falcon Heavy is super expensive compared to Proton and to a lesser degree Ariane 5 in upper position ! Difficult to imagine more than 1 Falcon Heavy commercial launch pre year with such pricing ....

Don't forget about payload processing at the site, other launch services and insurance costs ( higher on an unproven lv)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dror on 04/06/2016 07:47 pm
From Arian 6 updates thread to this one -
Keep in mind that the advertised Falcon 9 GTO payload is not a direct comparison to the Ariane 6 GTO payload, since Ariane 6 specifies GEO -1,500 m/s ish versus Falcon 9's GEO - 1,800 m/s ish.  Subtract a tonne or so from Falcon 9 payload to directly compare.  There's even a chance that Airbus Safran is talking about the advertised Falcon Heavy GTO payload, which is 6.4 tonnes.

 - Ed Kyle

This claim again ...

I have never seen this advertised.
Spacex's site clearly states 21,200 kg to GTO.
http://www.spacex.com/falcon-heavy

The old old site had this number as a price point but never as a performance goal.

So please state your source, Ed, or stop spreading that number...

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: tobi453 on 04/06/2016 07:50 pm
From Arian 6 updates thread to this one -
Keep in mind that the advertised Falcon 9 GTO payload is not a direct comparison to the Ariane 6 GTO payload, since Ariane 6 specifies GEO -1,500 m/s ish versus Falcon 9's GEO - 1,800 m/s ish.  Subtract a tonne or so from Falcon 9 payload to directly compare.  There's even a chance that Airbus Safran is talking about the advertised Falcon Heavy GTO payload, which is 6.4 tonnes.

 - Ed Kyle

This claim again ...

I have never seen this advertised.
Spacex's site clearly states 21,200 kg to GTO.
http://www.spacex.com/falcon-heavy

The old old site had this number as a price point but never as a performance goal.

So please state your source, Ed, or stop spreading that number...



Its right here:
http://www.spacex.com/about/capabilities
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: woods170 on 04/06/2016 08:17 pm
From Arian 6 updates thread to this one -
Keep in mind that the advertised Falcon 9 GTO payload is not a direct comparison to the Ariane 6 GTO payload, since Ariane 6 specifies GEO -1,500 m/s ish versus Falcon 9's GEO - 1,800 m/s ish.  Subtract a tonne or so from Falcon 9 payload to directly compare.  There's even a chance that Airbus Safran is talking about the advertised Falcon Heavy GTO payload, which is 6.4 tonnes.

 - Ed Kyle

This claim again ...

I have never seen this advertised.
Spacex's site clearly states 21,200 kg to GTO.
http://www.spacex.com/falcon-heavy (http://www.spacex.com/falcon-heavy)

The old old site had this number as a price point but never as a performance goal.

So please state your source, Ed, or stop spreading that number...



Its right here:
http://www.spacex.com/about/capabilities (http://www.spacex.com/about/capabilities)
Yes it is. And then again it isn't. See below. What to believe....
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GWH on 04/06/2016 08:21 pm
One is reusable performance and price, other (21t) is expendable capacity.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Reflectiv on 04/06/2016 08:22 pm
I don't understand the confusion, there are two sections - PRICE, under which is Standard Payment plan (doesnt mean it is the only one) and PERFORMANCE.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dror on 04/06/2016 08:34 pm
One is reusable performance and price, other (21t) is expendable capacity.
Now that's just another unsupported repeated claim.
It doesn't say that, it only says that the price for a certain load (6.4ton) is 90m$ and that total performance is again 21200kg, doesn't it?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: symbios on 04/06/2016 09:14 pm
Dror you are right.

That does not mean that GWH is wrong. I think most people interpret it the way that GWH does.

If it was expendable, the payload would be higher. If not expendable, then it will be at least in part reusable, what parts that are to be reused are up for grabs :)

One is reusable performance and price, other (21t) is expendable capacity.
Now that's just another unsupported repeated claim.
It doesn't say that, it only says that the price for a certain load (6.4ton) is 90m$ and that total performance is again 21200kg, doesn't it?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: llanitedave on 04/06/2016 10:36 pm
One is reusable performance and price, other (21t) is expendable capacity.
Now that's just another unsupported repeated claim.
It doesn't say that, it only says that the price for a certain load (6.4ton) is 90m$ and that total performance is again 21200kg, doesn't it?


That would imply that the Falcon Heavy reusable costs more than the Falcon 9 expendable.  But since they've never set a reusable price, one can only assume that all quoted prices are for expendable launchers.  The easiest interpretation is that for payloads heavier than 6.4 tons, contact the company for a custom price.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rockets4life97 on 04/06/2016 10:41 pm
The easiest interpretation is that for payloads heavier than 6.4 tons, contact the company for a custom price.

I think too much is being made of these numbers. Almost certainly each company that currently has a FH contract got a custom price. Shotwell also said about a month ago that the publicly released FH performance numbers were going to be updated (which hasn't happened yet). This whole discussion will change once we get new numbers.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LastStarFighter on 04/07/2016 01:49 am
The easiest interpretation is that for payloads heavier than 6.4 tons, contact the company for a custom price.

I think too much is being made of these numbers. Almost certainly each company that currently has a FH contract got a custom price. Shotwell also said about a month ago that the publicly released FH performance numbers were going to be updated (which hasn't happened yet). This whole discussion will change once we get new numbers.

We also know that the ViaSat-2 Ex-Im loan changed by $138m when they left SpaceX and went to Ariane 5. Which suggests what a dedicated FH launch plus insurance might cost. At least at the time that contract was signed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: su27k on 04/07/2016 02:27 am
Keep in mind that the advertised Falcon 9 GTO payload is not a direct comparison to the Ariane 6 GTO payload, since Ariane 6 specifies GEO -1,500 m/s ish versus Falcon 9's GEO - 1,800 m/s ish.  Subtract a tonne or so from Falcon 9 payload to directly compare.  There's even a chance that Airbus Safran is talking about the advertised Falcon Heavy GTO payload, which is 6.4 tonnes.

 - Ed Kyle

The quote from SpaceNews clearly states it's Falcon 9 they're talking about: "Ariane 6 will have twice the mass and twice the volume of the Falcon 9, at less than twice the price", if the designer of Ariane 6 couldn't distinguish F9 from FH, I think they have a bigger problem...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: S.Paulissen on 04/07/2016 03:46 am
The easiest interpretation is that for payloads heavier than 6.4 tons, contact the company for a custom price.

I think too much is being made of these numbers. Almost certainly each company that currently has a FH contract got a custom price. Shotwell also said about a month ago that the publicly released FH performance numbers were going to be updated (which hasn't happened yet). This whole discussion will change once we get new numbers.

We also know that the ViaSat-2 Ex-Im loan changed by $138m when they left SpaceX and went to Ariane 5. Which suggests what a dedicated FH launch plus insurance might cost. At least at the time that contract was signed.

https://www.casact.org/pubs/forum/00fforum/00ff047.pdf

This suggests that insurance premiums are floating between 5-10%, with ~7% being a reasonable estimate for a launch coverage (norm seems to be launch cost and 1-5 years on orbit coverage).  This includes launch costs AND satellite costs AND profit loss for the duration negotiated. 

Viasat revenue for a Viasat-2 is estimated as $45m per month and Viasat3 is supposed to have three times the bandwidth of Viasat2 so I conservatively estimate it's revenue at $135m per month and profit at a 7% margin to get ballpark $113m profit per year.  To insure this at 7% rate it would cost $7.9m

http://spacenews.com/viasat-details-1-4-billion-global-ka-band-satellite-broadband-strategy-to-oust-incumbent-players/


Also, Viasat2 cost $358m with claims that Viasat3 would be cheaper.  Lets call it $300m.  So to insure this satellite at 7% rate it comes to $21m
http://spacenews.com/35470viasat-puts-a-price-tag-on-its-boeing-built-behemoth/

So if we assume a case where Viasat insures for one year on orbit and the cost of the satellite alone (forget launch costs for the moment)  The total cost to insure is ~$29m, with a lot of growth potential.  This takes falcon heavy launch costs down from the $138m down to $109m.  In reality it's probably even lower because I didn't factor in the cost of the launch itself into the insurance cost and in all likelihood would increase it another $5-6m nor the possibility that the satellite is incredibly important for Viasat so they may be insuring for more than a single year on orbit at around $8m per year OR that revenue increase scales non-1 to 1 with bandwidth which is true for Viasat2 getting 10x the revenue of Viasat1 with only 2.5x more bandwidth.  It also ignores the costs involved with storing, transporting and integrating the satellite. This rapidly converges the launch price down to very close or below $90m.

On the other hand, the Viasat launch may be insured by a non-american company and not part of its loan from the Im-Ex band,so that all of this estimation means nothing XD.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 04/07/2016 03:00 pm
The easiest interpretation is that for payloads heavier than 6.4 tons, contact the company for a custom price.

I think too much is being made of these numbers. Almost certainly each company that currently has a FH contract got a custom price. Shotwell also said about a month ago that the publicly released FH performance numbers were going to be updated (which hasn't happened yet). This whole discussion will change once we get new numbers.

We also know that the ViaSat-2 Ex-Im loan changed by $138m when they left SpaceX and went to Ariane 5. Which suggests what a dedicated FH launch plus insurance might cost. At least at the time that contract was signed.
Launch plus insurance *plus payload processing, shipping, initial orbital checkout, etc*.  The ExIm loan covers all parts of the total launch cost which are paid to American companies.  Switching the satellite from SpaceX might mean that DHL gets shipping contracts instead of FedEx, prelaunch checkout and fueling in Europe instead of the Cape, fuel purchase and hazmat disposal done there, that a ground station in Europe does initial checkout instead of one in the US, that employees stay in European hotels instead of American ones, eat at European restaurants, use European contractors for incidentals, etc.  And we don't know how much of that loan is margin, "loan approval for up to $XYZ", instead of actual known fixed costs.  For all we know, the approved loan amount could have included a provision for discounted relaunch in case of failure. I think the number is only useful as a "SpaceX costs are known to be less than $X" number without further insight and a detailed cost breakdown.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/07/2016 05:05 pm
Isn't the 6.2 tons to GSO or GTO for expendable Falcon 9 Full Thrust, not heavy?  It lists 4.2 tons, but that may be with recovery of Falcon 9 FT.  Yes, the web site needs updating bad.  They also need to list expendable and recovery mode payloads.  They also should list pricing for used rockets, expendable rockets, and recoverable rockets.  It would give customers wider variety of choices, payloads, and costs.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kansan52 on 04/07/2016 05:28 pm
  They also need to list expendable and recovery mode payloads.  They also should list pricing for used rockets, expendable rockets, and recoverable rockets.  It would give customers wider variety of choices, payloads, and costs.

I'd suggest that they do not need to change any of that. They may have needed that information to attract customers in the early day when they were new to the industry. While it would be nice for us, they likely have conversations with customers about needs and costs. The customer is attracted to SX without looking at prices on the web site.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/07/2016 05:37 pm
SpaceX should at least list payloads using various modes on their website. Other providers do that, in detail.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 04/07/2016 05:55 pm
I'm not sure SpaceX thinks of reuse vs. expendable the way some seem to characterize. In the relatively near future, there won't be any "Expendable" vs. "Recoverable" launches. F9 & FH will always be designated and launched for return/reuse. That's what they are designed to do. Eventually we'll stop thinking of these launchers as expendable or recoverable.

We still make the differentiation because FH is not ready yet and neither vehicle has proved operational from different flight, payload and subsequent return profiles, CRS vs. Orbcom vs. SES for example.

SpaceX will offer the F9 and FH with associated prices for what payloads to what orbit. Eventually they will have new and previously flown prices to accompany them.  There will always be one-off configurations (center core FH expended, etc.) but not as standard offerings. Both these launchers are meant to be reused and therefore meant to be returned. If the payload can't be lifted on a F9 it will be moved to a FH when the time comes. Etc...

I believe we're still about 12 to 18 (if not more) months out from having a transparent re-use process and pricing model available. imo.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 04/13/2016 05:53 pm
I've been thinking about the returns of the FH cores to LZ-1 and or the ADSD. 

Assuming all 3 cores are recovered, do we have estimates for how much longer the core stage will burn compared to the sides and how much later it would be for a LZ-1 and ASDS landing?

With the core throttling back it's hard to see the solo core burn time being more than 20-25 seconds.

Edit: And the core landing at LZ-1 maybe 1:00 or so later than the sides.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Navier–Stokes on 04/13/2016 06:19 pm
I've been thinking about the returns of the FH cores to LZ-1 and or the ADSD. 

Assuming all 3 cores are recovered, do we have estimates for how much longer the core stage will burn compared to the sides and how much later it would be for a LZ-1 and ASDS landing?

With the core throttling back it's hard to see the solo core burn time being more than 20-25 seconds.

Edit: And the core landing at LZ-1 maybe 1:00 or so later than the sides.
The FH core will have a much higher (horizontal) velocity than the F9 first stage. As such, RTLS will not be a viable option for most launches (besides, perhaps, the demonstration launches) due to the very high performance penalty associated with it. Rather, I would expect the boosters to land at LZ-1 and the central core to land on an ASDS.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Doesitfloat on 04/13/2016 09:09 pm
I've been thinking about the returns of the FH cores to LZ-1 and or the ADSD. 

Assuming all 3 cores are recovered, do we have estimates for how much longer the core stage will burn compared to the sides and how much later it would be for a LZ-1 and ASDS landing?

With the core throttling back it's hard to see the solo core burn time being more than 20-25 seconds.

Edit: And the core landing at LZ-1 maybe 1:00 or so later than the sides.
The FH core will have a much higher (horizontal) velocity than the F9 first stage. As such, RTLS will not be a viable option for most launches (besides, perhaps, the demonstration launches) due to the very high performance penalty associated with it. Rather, I would expect the boosters to land at LZ-1 and the central core to land on an ASDS.

Forgive all the "is it possible phrases" but I don't know how to phrase these without claiming they are true.  Plus who wants to put stuff on the internet that is "wrong."

They have several way to launch FH; expendable, boosters RTLS main to barge and others. 
Is it possible that what we are seeing now with recovered boosters and re-flight (maybe in 3 months)  that there may be more ways to build FH ?

Is it possible that the price of 90 million for 6.4 mT to GTO included the price for 3 new boosters, and that profile was all Cores RTLS?

Is it possible, since Spacex announced that the F9 core and FH Booster core could be interchangeable, that Spacex could fly FH with new main core and re-flight boosters?

Is it possible, if re-flight boosters are used a new (lower) price could be announced?

Is it possible, that a new FH main core with re-flight boosters all  cores RTLS could cost equal or less than 62 million?

Is it possible,  that Spacex could offer current GTO customers the FH re-flight booster option and give the satellite the extra performance;  changing the recovery from single stage barge  to 3 core RTLS?


Is it possible, using this option to gain flight history on FH and re-flight cores?

Is it possible, Spacex could offer FH with all 3 core in re-flight condition ?

Would that price be more or less than 62 million?




Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 04/13/2016 10:41 pm
I've been thinking about the returns of the FH cores to LZ-1 and or the ADSD. 

Assuming all 3 cores are recovered, do we have estimates for how much longer the core stage will burn compared to the sides and how much later it would be for a LZ-1 and ASDS landing?

With the core throttling back it's hard to see the solo core burn time being more than 20-25 seconds.

Edit: And the core landing at LZ-1 maybe 1:00 or so later than the sides.

See my post with the attached FH spreadsheet at http://forum.nasaspaceflight.com/index.php?topic=34077.msg1500227#msg1500227 also read the posts it refers to.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 04/13/2016 11:32 pm
The FH core will have a much higher (horizontal) velocity than the F9 first stage. As such, RTLS will not be a viable option for most launches (besides, perhaps, the demonstration launches) due to the very high performance penalty associated with it. Rather, I would expect the boosters to land at LZ-1 and the central core to land on an ASDS.
That assumption is made frequently. But I am not sure it is actually correct. I suspect that the majority of launches to GTO is just beyond the capability of Falcon 9. So even with only a small range of payload weight for 3 core RTLS it is quite possible that most payloads will fall into that range.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Navier–Stokes on 04/14/2016 04:13 am
The FH core will have a much higher (horizontal) velocity than the F9 first stage. As such, RTLS will not be a viable option for most launches (besides, perhaps, the demonstration launches) due to the very high performance penalty associated with it. Rather, I would expect the boosters to land at LZ-1 and the central core to land on an ASDS.
That assumption is made frequently. But I am not sure it is actually correct. I suspect that the majority of launches to GTO is just beyond the capability of Falcon 9. So even with only a small range of payload weight for 3 core RTLS it is quite possible that most payloads will fall into that range.

Given the performance margin on the FH, I wouldn't be surprised if 3 core RTLS becomes increasing common as the launch vehicle and boostback/reentry/landing sequence becomes more optimized. Elon did just say that in the long run they're hoping to move from 50% ASDS for the F9 to just 33/25%.

The source for the central core ASDS landing being most common is a quote by Elon during the ORBCOMM-2 post-landing teleconference:
Quote from: Elon Musk
Q: My question deals with the next booster, the Falcon Heavy. How much of this successful landing can be applied or scaled up that heavy rocket and does it boost your confidence for that booster too?

A: The Falcon Heavy essentially consists of the Falcon 9 with two modified boost stages attached as strap on boosters. That would be quite an exciting aerial ballet with the two side boosters dropping off and doing a symmetric pirouette back to the launch site. We'd need to have another landing spot for the two boosters and then a third one for the center core. Although I think most of the Falcon Heavy missions will see the center core land on a ship most likely. It's really going ridiculously fast. The transfer energy of Falcon Heavy will more than double that of Falcon 9. The maximum transfer energy is approaching a terajoule.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 04/14/2016 06:05 am
The FH core will have a much higher (horizontal) velocity than the F9 first stage. As such, RTLS will not be a viable option for most launches (besides, perhaps, the demonstration launches) due to the very high performance penalty associated with it. Rather, I would expect the boosters to land at LZ-1 and the central core to land on an ASDS.
That assumption is made frequently. But I am not sure it is actually correct. I suspect that the majority of launches to GTO is just beyond the capability of Falcon 9. So even with only a small range of payload weight for 3 core RTLS it is quite possible that most payloads will fall into that range.

Given the performance margin on the FH, I wouldn't be surprised if 3 core RTLS becomes increasing common as the launch vehicle and boostback/reentry/landing sequence becomes more optimized. Elon did just say that in the long run they're hoping to move from 50% ASDS for the F9 to just 33/25%.

The source for the central core ASDS landing being most common is a quote by Elon during the ORBCOMM-2 post-landing teleconference:
Quote from: Elon Musk
Q: My question deals with the next booster, the Falcon Heavy. How much of this successful landing can be applied or scaled up that heavy rocket and does it boost your confidence for that booster too?

A: The Falcon Heavy essentially consists of the Falcon 9 with two modified boost stages attached as strap on boosters. That would be quite an exciting aerial ballet with the two side boosters dropping off and doing a symmetric pirouette back to the launch site. We'd need to have another landing spot for the two boosters and then a third one for the center core. Although I think most of the Falcon Heavy missions will see the center core land on a ship most likely. It's really going ridiculously fast. The transfer energy of Falcon Heavy will more than double that of Falcon 9. The maximum transfer energy is approaching a terajoule.

It really depends how you count the %....

If an FH does barge recovery of the center core, does that count as a barge mission, or as 33% barge mission, since two cores returned to land?

I am pretty sure that satellites will grow to take advantage of the increased capacity of FH.  It's just like cities grow to clog extra freeway lanes...

Since barge recovery is a lot closer to RTLS than it is to expending the core (cost wise), the operators will just throw more mass at it. (If they haven't already...)

Also, don't forget Mars missions.  SpaceX has lots and lots of plans. FH to Mars will need performance, and so expect barge landings there.

The only "free variable" is the cost tradeoff between an F9-to-barge and FH-full-RTLS.   If reusability works exceedingly well, the FH-full-RTLS will win over F9-to-barge, and then we'll get to see a lot of 3-booster landings...  :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 04/14/2016 06:56 am
Also, don't forget Mars missions.  SpaceX has lots and lots of plans. FH to Mars will need performance, and so expect barge landings there.

I certainly hope you are right. But I expect that the best we can hope for is booster RTLS and an expendable central core to get a Red Dragon to Mars.

BTW in my personal list of options for FH Booster landing on barge is not included. Boosters will RTLS and Central may do barge landing. I just cannot see 3 barges out there to catch 3 cores.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 04/14/2016 07:03 am
Also, don't forget Mars missions.  SpaceX has lots and lots of plans. FH to Mars will need performance, and so expect barge landings there.

I certainly hope you are right. But I expect that the best we can hope for is booster RTLS and an expendable central core to get a Red Dragon to Mars.

BTW in my personal list of options for FH Booster landing on barge is not included. Boosters will RTLS and Central may do barge landing. I just cannot see 3 barges out there to catch 3 cores.
Certainly agreed on no-barge for side cores.

FH to Mars configurations are a big TBD.

With no boost-back, we don't even know what the penalty is.  I always figured the boost-back is the most expensive burn, followed by reentry and then landing.

There may be tricks yet in reducing reentry burns.  This is where the magic sauce has always been, and I doubt that they are done exploring possibilities.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: yg1968 on 04/15/2016 12:04 am
Quote from: Jeff Foust
Shotwell, as she did last month, says SpaceX plans to fly about 18 times this year, including Falcon Heavy introduction.

https://twitter.com/jeff_foust/status/720730436180160512
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Herb Schaltegger on 04/15/2016 01:33 am
Quote from: Jeff Foust
Shotwell, as she did last month, says SpaceX plans to fly about 18 times this year, including Falcon Heavy introduction.

https://twitter.com/jeff_foust/status/720730436180160512

Love the optimism, but yeah. Still gonna take the "under" on this one. I'm still guessing about 12 if nothing seriously Bad™ happens along the way. Hope to be proven wrong.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 04/15/2016 04:42 am
Quote from: Jeff Foust
Shotwell, as she did last month, says SpaceX plans to fly about 18 times this year, including Falcon Heavy introduction.

https://twitter.com/jeff_foust/status/720730436180160512

Love the optimism, but yeah. Still gonna take the "under" on this one. I'm still guessing about 12 if nothing seriously Bad™ happens along the way. Hope to be proven wrong.

Agreed, 12 including a FH would be a very good year.  Getting the FH on the stand and off the ground, successfully, will be a massive accomplishment.

Just having the payloads on hand at the right times is something that would need to be planned already. 

Good to have goals though.

Edit: Missed a quote bracket
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 04/15/2016 09:13 am
Of course, an F9H flight probably counts as three landings...they'll get a lot of data from that flight if they all land successfully (or, tbh unsuccessfully)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: IainMcClatchie on 04/16/2016 03:30 am
Certainly agreed on no-barge for side cores.

Hmm.  They probably aren't going to land boosters at the Florida Keys, and RTLS is a very big performance hit.  Barges are what is left.  And they've been proven to work.

The Florida Keys are 1500 km from Boca Chica.

To get a booster to the Keys, coasting from separation, would require a separation velocity of over 4 km/s at a pitch angle (from the horizon) of 27 degrees.  Even assuming a pitch angle at separation of 45 degrees, it would require a separation velocity of 2700 m/s.  It seems to me the booster separation is going to happen much more slowly than this, more like the 2200 m/s that MODEMEAGLE posted.  Maybe even more slowly than that.

A Falcon Heavy upper stage:
   * payload 53,000 kg
   * empty mass 3,900 kg
   * propellant mass 92,670 kg
   * exhaust velocity 3335 m/s
   * delta-V 5366 m/s
   * orbital velocity 7672 m/s

These numbers don't make sense to me, because they make it look like the upper stage can start at something like 3000 m/s.  The system as a whole has too much delta-V and it seems like it ought to put a lot more payload into orbit.  Anyway, at 3000 m/s separation it is just possible to get the core to the Florida Keys.

My guess is that all three land on barges.  The flexibility of these things is just irresistible.  You can move them around depending on your orbit inclination.  You can adjust for different payloads, and maybe even avoid some bad weather.

Suppose each barge costs $3m/year to operate, and you need three to support four Falcon Heavy launches per year.  For $9m you increased the payload of ~$400m of launches by ~30%.  That's fabulous.  Heck, it pays for itself with even one launch.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gadgetmind on 04/16/2016 11:20 am
I guess we'll know soon enough as it's always taken a few months to turn a Marmac *barge* into an Autonomous Spaceport Drone *Ship*.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jcc on 04/16/2016 11:56 am
I guess we'll know soon enough as it's always taken a few months to turn a Marmac *barge* into an Autonomous Spaceport Drone *Ship*.

They won't be needed until next year at the earliest, and really not until they have a mission that needs the extra dV. They have 4 FH missions on the manifest after the demo, INMARSAT, INTELSAT, STP-2 and VIASAT. I'm not aware than any of those would not allow RTLS for the side cores.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Zed_Noir on 04/16/2016 12:22 pm
I guess we'll know soon enough as it's always taken a few months to turn a Marmac *barge* into an Autonomous Spaceport Drone *Ship*.

They won't be needed until next year at the earliest, and really not until they have a mission that needs the extra dV. They have 4 FH missions on the manifest after the demo, INMARSAT, INTELSAT, STP-2 and VIASAT. I'm not aware than any of those would not allow RTLS for the side cores.

Disagree. SpaceX needs at least one spare ASDS per launch facility to assure ASDS availability for recovery sorties. A few extra ASDS is cheap as compare to the lost of a Falcon core.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gadgetmind on 04/16/2016 03:45 pm
I also recall they only had permission to land a single core at the cape. Of course, this could change, but I think their brace of ASDS is going to have to turn into a small fleet.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 04/16/2016 05:06 pm


A Falcon Heavy upper stage:
   * payload 53,000 kg
   * empty mass 3,900 kg
   * propellant mass 92,670 kg
   * exhaust velocity 3335 m/s
   * delta-V 5366 m/s
   * orbital velocity 7672 m/s

These numbers don't make sense to me, because they make it look like the upper stage can start at something like 3000 m/s.  The system as a whole has too much delta-V and it seems like it ought to put a lot more payload into orbit.  Anyway, at 3000 m/s separation it is just possible to get the core to the Florida Keys.


First the FT version of the upper stage is slightly different than the numbers above, with a dry weight above 5t and a prop load around 115t.

2nd the sideboosters if run until empty but with the centre core shutting down engines until only 4 are running then throttling down to 70%, then the side core separate at about 2,000m/s and the centre core still has 47% of its propellant remaining. And with a 53t payload can add another 2,100m/s to the upper stage if burned dry. However at 53t I don't see it the upper stage imparting more than 3800m/s to the payload.

In an RTLS mode for the side cores and down range recovery mode for the centre core at 30t payload I get the side cores separating at 1,400 m/s with 16% of their prop remaining, and the centre core adding 1,500m/s to that with the 52.5% propellant remaining at side core separation while having a 15% prop load remaining at MECO (which would probably be a little more than enough for a non or minimal boostback and only doing re-entry retropulsion and landing, certainly significantly more margin than SES-9 had).  At 30t the upper stage could add 4,900m/s.

To see where my numbers come from, check out post http://forum.nasaspaceflight.com/index.php?topic=34077.msg1500227#msg1500227 (http://forum.nasaspaceflight.com/index.php?topic=34077.msg1500227#msg1500227)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Avron on 04/16/2016 05:21 pm
I also recall they only had permission to land a single core at the cape. Of course, this could change, but I think their brace of ASDS is going to have to turn into a small fleet.

All they need is an FAA licence to land and a go from the range. The landing is part of the launch licence see: https://www.faa.gov/about/office_org/headquarters_offices/ast/environmental/nepa_docs/review/launch/media/20151201_FAA_FONSI_for_F9_RTLS_at_LC-1.pdf
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mme on 04/16/2016 06:52 pm
I also recall they only had permission to land a single core at the cape. Of course, this could change, but I think their brace of ASDS is going to have to turn into a small fleet.

All they need is an FAA licence to land and a go from the range. The landing is part of the launch licence see: https://www.faa.gov/about/office_org/headquarters_offices/ast/environmental/nepa_docs/review/launch/media/20151201_FAA_FONSI_for_F9_RTLS_at_LC-1.pdf
GadgetMind is referring to the Environmental Impact Statement that explicitly stated only landing one stage at a time.  Presumably they will need to amend this.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: watermod on 04/17/2016 02:44 am
When they start to launch from Boca Chica would a center core landing someplace like Hospital Key be totally ruled out by the Dept of Interior?

If so,  would they be permitted to place landing pads on pier supports in places near there our would those waters be under the Dept of Interior too?    (trying to get a conceptual handle on how much land and water there is viewed as National Parklands)


Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: OnWithTheShow on 04/17/2016 04:04 am
I dont think the center core makes it that far.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 04/17/2016 09:08 pm
I suspect it will take more than "a couple months" to make more ASDSes: we're near the end of the existing MARMAC fleet.  Only one or two of those left, assuming you can recall MARMAC 300 from wind turbine duty.  If you're thinking there are going to be three on each coast and another three for boca chica, then they are either going to have to get some more marmac-class barges built, or else inaugurate a new ASDS class.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/17/2016 10:12 pm
I also recall they only had permission to land a single core at the cape. Of course, this could change, but I think their brace of ASDS is going to have to turn into a small fleet.

LZ-1 has five pads, with the intention of being able to bring back all three cores of an FH in certain scenarios, and still having two more in reserve. I imagine the original landing permit was for one core because it was a first attempt and only one core was flying
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: the_other_Doug on 04/18/2016 01:09 am
I also recall they only had permission to land a single core at the cape. Of course, this could change, but I think their brace of ASDS is going to have to turn into a small fleet.

LZ-1 has five pads, with the intention of being able to bring back all three cores of an FH in certain scenarios, and still having two more in reserve. I imagine the original landing permit was for one core because it was a first attempt and only one core was flying

Well -- there is a CGI artist's impression of LZ-1 that has five landing pads.  As of right now, there is one landing pad at LZ-1, and no reliable report of any earth-clearing going on yet to make even a second one.

Just sayin'...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Avron on 04/18/2016 01:54 am
I also recall they only had permission to land a single core at the cape. Of course, this could change, but I think their brace of ASDS is going to have to turn into a small fleet.

LZ-1 has five pads, with the intention of being able to bring back all three cores of an FH in certain scenarios, and still having two more in reserve. I imagine the original landing permit was for one core because it was a first attempt and only one core was flying

Environmental assessment and recommendation, is for one returning stage .. two will require a reassessment and licencing for FH 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: IainMcClatchie on 04/18/2016 06:18 am
First the FT version of the upper stage is slightly different than the numbers above, with a dry weight above 5t and a prop load around 115t.

Thank you.  Looks like I fumbled the rocket equation, as well as getting the wrong start numbers.

So now I have
   * payload 53,000 kg
   * empty mass 5,100 kg
   * propellant mass 115,000 kg
   * exhaust velocity 3335 m/s = (340 s)*(9.81 m/s^2)
   * delta-V 3641 m/s = (3335 m/s)*ln((173100 kg)/(58100 kg))
   * orbital velocity 7672 m/s

Okay, this makes a lot more sense.  Now the upper stage is starting at something like 4000 m/s.

That means the core stage can coast all the way to the keys... but only when the orbit points it in exactly the right direction.  Yep, I'm thinking ASDS for the core all the time.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 04/18/2016 06:42 am
That means the core stage can coast all the way to the keys... but only when the orbit points it in exactly the right direction.  Yep, I'm thinking ASDS for the core all the time.

And that is the only direction that they will launch out of Texas - the ground track will always take it close to the keys. It would only need a fairly small burn to aim the stage to the keys.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: IainMcClatchie on 04/18/2016 06:57 am
Lars, why are all launches out of Texas going to be over the same ground track?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Owlon on 04/18/2016 08:56 am
Lars, why are all launches out of Texas going to be over the same ground track?

Because everything else involves passing over land. You have to aim between the Yucatan Peninsula and Cuba, or Cuba and Florida. The second option gives a lower orbital inclination.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: groundbound on 04/18/2016 03:47 pm
That means the core stage can coast all the way to the keys... but only when the orbit points it in exactly the right direction.  Yep, I'm thinking ASDS for the core all the time.

And that is the only direction that they will launch out of Texas - the ground track will always take it close to the keys. It would only need a fairly small burn to aim the stage to the keys.

Unless someone relocated Cuba while we weren't paying attention.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 04/18/2016 04:42 pm
Lars, why are all launches out of Texas going to be over the same ground track?

Because everything else involves passing over land. You have to aim between the Yucatan Peninsula and Cuba, or Cuba and Florida. The second option gives a lower orbital inclination.

Yep. Here is a map showing where the launches will fly over - close to the keys.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: watermod on 04/18/2016 05:16 pm
That's why I asked my question about how much land and water near/in the Keys is viewed as National Parklands.    I was trying to figure what uninhabited Keys or vacant land on Key islands could be landed on or shallow waters where it would be permissible to build a landing platform(s).   If one takes the way the Interior Department treats parks under their control one would assume no permission would ever be granted under any circumstances on land/water they control.   

Maybe the better way to look at it instead of the big NO would be which islands might permit it?

(I still think the Dry Tortugas would be ideal if they were not a National Park).


Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: philw1776 on 04/18/2016 08:20 pm
Loggerhead Key landing site is only maybe 2 miles closer to Texas than the main section of Dry Tortugas NP

The flash boiled turtle eggs of the nesting turtles would be an added bonus
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Blackjax on 04/19/2016 12:40 am
I've been following this thread and a few pages back I saw a bunch of discussion around the flight rate of the FH.  The gist of it was that the F9 can cover a lot of the existing market demand if you stretch its abilities and consequently that would cannibalize the possible set of payloads for the FH, resulting in a low flight rate.  That got me wondering, what would things look like if you started with a different premise, not how can you stretch the F9 to cover as much of the manifest as possible, but rather what if you optimized for the heaviest possible RTLS/reuse across both vehicles.

I am wondering if I can find any takers to work through the following thought exercise.  Here are the assumptions:

Assume that Elon has directed his team to optimize the company for maximizing reuse with the shortest turnaround time they can manage.  Vehicle preference is in the following order regardless of whether it leaves payload capacity unutilized or whether the FH is more expensive in general, you are optimizing for RTLS & getting the returned vehicle refitted for another flight ASAP:

F9 RTLS
FH 3 core RTLS
F9 ASDS
FH 2 core RTLS, 1 core ASDS
FH 3 core ASDS
FH 2 core ASDS, 1 expendable
FH 3 core expendable

Assume that the market is mostly indifferent to the price difference between the options and that your manifest is fixed at the following regardless of the cost to the customers:  https://forum.nasaspaceflight.com/index.php?topic=40049.msg1520510#msg1520510

Assume that the profit margin on any of the above vehicles is acceptable so long as you are maximizing RTLS and rapid reuse.

Finally, assume that there are no technology changes and the rockets remain basically as we understand them to be as of our best information to date.  No raptor upper stages or theoretical performance improvements we might speculate on.

The question is, if you optimize for rapid reuse alone, how does this change how much the FH flies and how would the payloads listed get distributed across the vehicle list above?

Any takers on doing the thought exercise?


Bonus Question:  Assuming that you started with a brand new F9 and FH, how many cores would the factory need to produce if you assumed that each core would be used as an expendable or retired for a teardown & analysis after some number of uses?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mvpel on 04/19/2016 03:02 am
Secretary of the Interior Sally Jewell was a guest at the CRS-8 launch.


Sent from my iPhone using Tapatalk
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GWH on 04/19/2016 01:32 pm
Assume that Elon has directed his team to optimize the company for maximizing reuse with the shortest turnaround time they can manage.  Vehicle preference is in the following order regardless of whether it leaves payload capacity unutilized or whether the FH is more expensive in general, you are optimizing for RTLS & getting the returned vehicle refitted for another flight ASAP:

That's an interesting thought, to truly achieve major savings through rapid reuse requires marginal costs per flight to be reduced on so many levels that barge recovery costs or added risk could become a significant factor.  So many unknowns however to even take a stab at, like:
- Do GTO missions on a single stick reduce stage life substantially, or require shorter refurb cycle due to more high velocity re-entry?
- Long term what is success rate of ASDS recovery? 
- Will a second ASDS be needed at each pad to cover increased flight rate or flyback from ASDS? Do weather limitations at sea start to place limits on recovery/launch attempts?
- Refurb of 3 cores every n flights or 1 core every n flight, which is cheaper?
- What is the ratio of demand on 3 core recovery to full capacity (expendable) FH?  If it works out to be something like 10 or 20 : 1 then my guess is the cost advantage to fly expendable class payloads at reused price would be a major incentive to increase flight rate of FH in full RTLS mode.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 04/19/2016 03:58 pm
Rather than shortest turnaround time they can manage, a better phrase might be in the shortest time that hits a cost minimum. You might not want to recycle too fast as that might make things MORE expensive.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: starhawk92 on 04/19/2016 05:02 pm
Cores are numbered; 1 is a brand-new F9FT; cores 2,3,4 are a brand-new FH.

Assumption:  CRS-8 went up on 4/8 and produced an ASDS-landed core.  It's been 10 days and the static fire hasn't happened yet, so I assume a core has a 20 day recycle period (i.e. can't be used on back-to-back mission).

Assumption:  You can strap any three cores together and call it a Falcon Heavy


  NET DATE   VEHICLE (CORE NUMBER)     1S Landing    ORBIT         PAYLOAD (& CO-PAYLOAD)                 
  04/28/16   Falcon 9 (1)              ASDS          GTO           JCSAT-14 (Replacing JCSAT-2A)           
  05/10/16   Falcon 9 (2 - New/1st)    ASDS          GTO           Eutelsat 117 West B & Asia Broadcast     
  05/24/16   Falcon 9 (1 - 2nd)        ASDS          GTO           Thaicom 8                               
  06/10/16   Falcon 9 (2 - 2nd)        ASDS          GTO           AMOS-6                                 
  06/24/16   Falcon 9 (1 - 3rd)                      LEO (Polar)   Iridium NEXT (Flight 1) 
  07/10/16   Falcon 9 (2 - 3rd)                      SSO (720km)   Formosat-5 & Sherpa SSO*
  07/24/16   Falcon 9 (1 - 4th)        RTLS          LEO (ISS)     Dragon (CRS 9)               
  08/10/16   Falcon 9 (2 - 4th)        ASDS          GTO           SES-10                       
  08/24/16   Falcon 9 (1 - 5th)        ASDS          GTO           JCSat-16                     
  09/10/16   Falcon 9 (2 - 5th)                      LEO (Polar)   Iridium NEXT (Flight 2)   
----> I'll retire 1 and 2 after 5 flights for teardown and much learning) 
  09/24/16   Falcon Heavy (3-1st, 4-1st, 5-1st)                    Falcon Heavy Demo Flight           
  10/10/16   Falcon 9 (3 - 2nd)                                    CREW Dragon (NASA DEMO 1)   
  10/24/16   Falcon 9 (4 - 2nd)                      LEO (ISS)     Dragon (CRS 10)         
  11/10/16   Falcon 9 (5 - 2nd)        ASDS          GTO           SES-11/Echostar 105     
  11/24/17   Falcon 9 (3 - 3rd)                      LEO (ISS)     Dragon (CRS 11)         
  12/10/17   Falcon 9 (4 - 3rd)                                    SES-16/GovSat           
  12/24/17   Falcon 9 (5 - 3rd)                                    SES-14             
  01/10/17   Falcon 9 (3 - 4th)        ASDS          GTO           Es’hail 2             
  01/24/17   Falcon 9 (4 - 4th)                      SSO           SAOCOM 1A                     
  02/10/17   Falcon 9 (5 - 4th)                      LEO (Polar)   Iridium (Flight 3)         
  02/24/17   Falcon 9 (3 - 5th)        ASDS          GTO           EuropaSat / HellasSat 3   
---->  retire 3
  03/10/17   Falcon Heavy (6-1st, 4-5th, 5-5th)      GTO           Inmarsate-5 F4       
---->  retire 4 and 5
  03/24/17   Falcon Heavy (6-2nd, 7-1st, 8-1st)                    Arabsat (Arabsat 6A)
  04/10/17   Falcon 9 (6 - 3rd)                                    Bigelow Aerospace   
  04/24/17   Falcon 9 (7 - 2nd)                                    Bulgaria Sat       
  05/10/17   Falcon 9 (8 - 2nd)                                    (1)CONAE (Argentina)   
  05/24/17   Falcon 9 (6 - 4th)                                    (2)CONAE (Argentina)


So, immediately two things appear to dictate core need -- success on ASDS landing and frequency of Falcon Heavy launches.  Eight cores lasted well into next year.  Also, turnaround rate vs. launch pace would be a "secondary" need indicator.  What I mean is that if the turnaround is longer, adding one more core buys "another launch" of ground time, so impact is less significant than losing two cores to landing mishaps.

Cool to ponder, thanks Blackjax!!  Hope I played by the rules!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gospacex on 04/19/2016 05:04 pm
Assume that Elon has directed his team to optimize the company for maximizing reuse with the shortest turnaround time they can manage.

SpaceX should optimize profit.

With current market situation, they can gobble up even entire world's launch market by launching about once a week. This does not require absolutely "shortest turnaround time".

Sure, FH RTLS may well end up to be shorter turnaround time than F9 ASDS.

But it uses three cores, increasing chances of losing a core to a landing mishap, and increasing wear of the cores. And more costly: FH does not need only more fuel; it also needs more work.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 04/19/2016 06:04 pm
I've been following this thread and a few pages back I saw a bunch of discussion around the flight rate of the FH.  The gist of it was that the F9 can cover a lot of the existing market demand if you stretch its abilities and consequently that would cannibalize the possible set of payloads for the FH, resulting in a low flight rate.  That got me wondering, what would things look like if you started with a different premise, not how can you stretch the F9 to cover as much of the manifest as possible, but rather what if you optimized for the heaviest possible RTLS/reuse across both vehicles.

I am wondering if I can find any takers to work through the following thought exercise.  Here are the assumptions:

Assume that Elon has directed his team to optimize the company for maximizing reuse with the shortest turnaround time they can manage.  Vehicle preference is in the following order regardless of whether it leaves payload capacity unutilized or whether the FH is more expensive in general, you are optimizing for RTLS & getting the returned vehicle refitted for another flight ASAP:

F9 RTLS
FH 3 core RTLS
F9 ASDS
FH 2 core RTLS, 1 core ASDS
FH 3 core ASDS
FH 2 core ASDS, 1 expendable
FH 3 core expendable

Assume that the market is mostly indifferent to the price difference between the options and that your manifest is fixed at the following regardless of the cost to the customers:  https://forum.nasaspaceflight.com/index.php?topic=40049.msg1520510#msg1520510

Assume that the profit margin on any of the above vehicles is acceptable so long as you are maximizing RTLS and rapid reuse.

Finally, assume that there are no technology changes and the rockets remain basically as we understand them to be as of our best information to date.  No raptor upper stages or theoretical performance improvements we might speculate on.

The question is, if you optimize for rapid reuse alone, how does this change how much the FH flies and how would the payloads listed get distributed across the vehicle list above?

Any takers on doing the thought exercise?


So using my spreadsheet (see post: http://forum.nasaspaceflight.com/index.php?topic=34077.msg1500227#msg1500227 (http://forum.nasaspaceflight.com/index.php?topic=34077.msg1500227#msg1500227)) I get the following:

FH 3 Core RTLS LEO payload: 25t  GTO payload: 7t
FH 2 Core RTLS 1 Core ASDS  LEO payload: 30t  GTO Payload 10t
FH 3 Core ASDS LEO payload 35t  GTO Payload 11t
FH 2 Core RTLS 1 Core ExpendableLEO payload 42t GTO Payload 15t
FH 2 Core ASDS 1 Core Expendable LEO payload 45t GTO payload 17t
FH 3 Core Expendable LEO 55t  GTO Payload GTO payload 20t

NOTE I did not see the option I have in bold above, but I think it is worth presenting as it handles a fairly large range of payloads.

My bias suggests that side cores are either expended or RTLS and Centre cores are either expended or ASDS and that we won't see any 3 core RTLS.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 04/19/2016 06:26 pm


Assumption:  You can strap any three cores together and call it a Falcon Heavy

I believe the current consensus is that the FH side cores and F9 single-stick cores are identical (just slap a nose cone on for FH), but that the center core of an FH is a unique and special snowflake (has extra load-bearing paths, mounts for side boosters, etc).

How does your analysis change under that assumption?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 04/19/2016 09:20 pm
Assume that Elon has directed his team to optimize the company for maximizing reuse with the shortest turnaround time they can manage.

SpaceX should optimize profit.


With current market situation, they can gobble up even entire world's launch market by launching about once a week. This does not require absolutely "shortest turnaround time".

Sure, FH RTLS may well end up to be shorter turnaround time than F9 ASDS.

But it uses three cores, increasing chances of losing a core to a landing mishap, and increasing wear of the cores. And more costly: FH does not need only more fuel; it also needs more work.
( bold emphasis in the above quote is mine )

This pushes the SpaceX Overton window to suggest optimizing for profit ( & revenue ) vs. cost alone, & the wonderous elegance of SpaceX having a single manufacturing line churning out 3.7 meter cores configured as F9 V1.2 or the very rare FH center core configuration.

Following the directive to optimize for profit & revenue is a direct challenge to the short & long term viability of FH.   FH is very appealing to the rocketry purist, who believes that the markets to support a high flight rate of FH will appear very quickly vs. far into the future, and thus justify the existing FH.   However, this is a speculative & dangerous basis as the foundation for a business plan.

The existing very marginal manifest for FH, as well as lack of candidate payloads for FH show it to be diminutive to SpaceX's overall current & future cash flow.   If it remains diminutive after FH's first few flights & fails to win launch contracts away from Ariane & Atlas in the +6.5t to GTO category,  it would imply that the market doesn't much care for the FH configuration for existing candidate payloads.   The large LEO payload capacity of FH seems to be for a completely speculative market yet to materialize.

What then for SpaceX?   Sure it cost's them very little to maintain a configuration that is rarely launched, but it also gains them nothing.   
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: IainMcClatchie on 04/20/2016 07:03 am
FH 3 Core RTLS LEO payload: 25t  GTO payload: 7t
FH 2 Core RTLS 1 Core ASDS  LEO payload: 30t  GTO Payload 10t
FH 3 Core ASDS LEO payload 35t  GTO Payload 11t
FH 2 Core RTLS 1 Core ExpendableLEO payload 42t GTO Payload 15t
FH 2 Core ASDS 1 Core Expendable LEO payload 45t GTO payload 17t
FH 3 Core Expendable LEO 55t  GTO Payload GTO payload 20t

Thank you for this table.  I've been looking for something like this for a while.

I find it counterintuitive that RTLS, which requires so much more delta-V from the boosters than ASDS (you have 3500 m/s vs 1500 m/s), has such a small payload hit.  I suppose it is explained by the incredibly large ratio between delta-V gained by the booster to delta-V lost to the payload by earlier separation.

Would you be willing to expand your table to show all these options with crossfeed vs not?  It wasn't clear to me how to use your spreadsheet to get these answers.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MATTBLAK on 04/20/2016 07:46 am
I have a hunch Space X ultimately will not bother with Propellant Crossfeed for Falcon Heavy; by the time the thing is well into operations, Elon will probably be into expending effort on developing the BFRs. Good uprating results for FH could come from a 'mere' upper stage upgrade.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Meltro on 04/20/2016 02:47 pm
I have a hunch Space X ultimately will not bother with Propellant Crossfeed for Falcon Heavy; by the time the thing is well into operations, Elon will probably be into expending effort on developing the BFRs. Good uprating results for FH could come from a 'mere' upper stage upgrade.

That is a bit of a bold assumption, considering Elon specifically talked about how putting together small gains made huge differences in rocket performance. Having a true asparagus staging solution vs. the throttled-back center stage puts some big numbers on the board, well worth it if it can be done. SpaceX has demonstrated they're willing to work out the technical problems for these gains, and if they get it to work, I very much doubt they'd go back. Even if they don't need it for the payload, it's just that much more fuel to work on landing options for the boosters.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 04/20/2016 03:09 pm
I have a hunch Space X ultimately will not bother with Propellant Crossfeed for Falcon Heavy; by the time the thing is well into operations, Elon will probably be into expending effort on developing the BFRs. Good uprating results for FH could come from a 'mere' upper stage upgrade.

That is a bit of a bold assumption, considering Elon specifically talked about how putting together small gains made huge differences in rocket performance. Having a true asparagus staging solution vs. the throttled-back center stage puts some big numbers on the board, well worth it if it can be done. SpaceX has demonstrated they're willing to work out the technical problems for these gains, and if they get it to work, I very much doubt they'd go back. Even if they don't need it for the payload, it's just that much more fuel to work on landing options for the boosters.

It's not that it isn't a good idea, just that the BFR development may well overtake it, and mean F9H crossfeed is unnecessary.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 04/20/2016 03:45 pm
FH 3 Core RTLS LEO payload: 25t  GTO payload: 7t
FH 2 Core RTLS 1 Core ASDS  LEO payload: 30t  GTO Payload 10t
FH 3 Core ASDS LEO payload 35t  GTO Payload 11t
FH 2 Core RTLS 1 Core ExpendableLEO payload 42t GTO Payload 15t
FH 2 Core ASDS 1 Core Expendable LEO payload 45t GTO payload 17t
FH 3 Core Expendable LEO 55t  GTO Payload GTO payload 20t

Thank you for this table.  I've been looking for something like this for a while.

I find it counterintuitive that RTLS, which requires so much more delta-V from the boosters than ASDS (you have 3500 m/s vs 1500 m/s), has such a small payload hit.  I suppose it is explained by the incredibly large ratio between delta-V gained by the booster to delta-V lost to the payload by earlier separation.

Would you be willing to expand your table to show all these options with crossfeed vs not?  It wasn't clear to me how to use your spreadsheet to get these answers.

Ok I will redo that table with a column for payload to TMI as well and do a duplicate table with crossfeed.

To explain what you see as counter intuitive the difference in propellant load on the side boosters to go from ASDS to RTLS is 5 to 15% of total propellant load which is 20t to 60t on a rocket with a dry weight of 25.6t.  A huge performance gain to make RTLS work (as you note from 1500m/s to 3500)  BUT when you are looking at the performance of the stages remaining the upper stage performance doesn't change at all, the centre core ends up with about 15t more fuel at side core separation which gives it about 100m/s more ΔV while the 80t more propellant (40*2) in the side cores only adds approximately 400m/s - so the upper stage only gets an extra 300m/s at its ignition compared to the extra 600 or so m/s you get by using ASDS vs RTLS for LEO launches on the centre core (note that RTLS for higher energy stuff is just too much for the centre core to provide much benefit except maybe with cross feed).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gospacex on 04/20/2016 03:57 pm
The existing very marginal manifest for FH, as well as lack of candidate payloads for FH show it to be diminutive to SpaceX's overall current & future cash flow.   If it remains diminutive after FH's first few flights & fails to win launch contracts away from Ariane & Atlas in the +6.5t to GTO category,  it would imply that the market doesn't much care for the FH configuration for existing candidate payloads.   The large LEO payload capacity of FH seems to be for a completely speculative market yet to materialize.

What then for SpaceX?   Sure it cost's them very little to maintain a configuration that is rarely launched, but it also gains them nothing.

With FH, SpaceX does not lose anything. When F9 can do, they will use F9. When an occasional super heavy (and therefore lucrative) payload appears, they slap together three F9s and have a FH. What's not too like? (Yes it's an oversimplification).

Launching more FHs just for the sake of it is not a goal.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 04/20/2016 03:59 pm
It's not that it isn't a good idea, just that the BFR development may well overtake it, and mean F9H crossfeed is unnecessary.
It amazes me that people think that the same SpaceX that is struggling to get the FH to the launchpad can somehow magically snap their fingers and conjure up the BFR, a whole new rocket with new engines that is bigger than anything anybody has ever launched before.  With new bigger infrastructure, new bigger environmental hurdles...

Yeah, crossfeed sounds really tough compared to that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: DavidH on 04/20/2016 04:11 pm
It's not that it isn't a good idea, just that the BFR development may well overtake it, and mean F9H crossfeed is unnecessary.
It amazes me that people think that the same SpaceX that is struggling to get the FH to the launchpad can somehow magically snap their fingers and conjure up the BFR, a whole new rocket with new engines that is bigger than anything anybody has ever launched before.  With new bigger infrastructure, new bigger environmental hurdles...

Yeah, crossfeed sounds really tough compared to that.
Who says they're struggling? I think that's not a quantifiable assertion. They've possibly just not prioritized it until F9FT can reliably land.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 04/20/2016 04:37 pm
FH is not exactly a walk in the development park.

-Managing 27 engines
-3 distinct return profiles, two of them simultaneous  - (associated hardware/software)
-An auto retractable booster separation mechanism.
-All based on a rocket version less than a year old that continues to be slightly modified each time they examine a retuned core.
-They don't have an approved autonomous FTS yet, which they'll need before launch/return as well as a second landing pad at LZ-1 for the second booster. (Assuming ASDS is used for Core landing)

I don't think they are struggling but between their RTF and subsequent ramping of F9 flight rate, cargo and crew Dragon and all the infrastructure development, there's only so much, so fast they can or even should take on.

Edit: And I'll add all the processes they need to streamline for returned cores. We all watched in interest how they went about this last weeks core return from the ASDS. Now imagine 2 simultaneous boosters at LZ-1 and the core just a few days behind them coming into port. That in and of itself is going to be a really interesting dance to witness.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 04/20/2016 04:46 pm
It's not that it isn't a good idea, just that the BFR development may well overtake it, and mean F9H crossfeed is unnecessary.
It amazes me that people think that the same SpaceX that is struggling to get the FH to the launchpad can somehow magically snap their fingers and conjure up the BFR, a whole new rocket with new engines that is bigger than anything anybody has ever launched before.  With new bigger infrastructure, new bigger environmental hurdles...

Yeah, crossfeed sounds really tough compared to that.

I think cross feed is an exciting idea and I could see it being developed for one key benefit. Allowing the central core do RTLS vs ASDS.

The fuel requirements and burn times for a central core RTLS will be significant and I think we're all learning the ASDS recovery is less reliable and much more intensive. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 04/20/2016 04:58 pm
So I have redone the table and made a graphic of it so that it can retain formatting.  Scenarios with all the cores returned have no shading, centre core expendables are yellow, all core expendables are red. 

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rst on 04/20/2016 05:11 pm
I have a hunch Space X ultimately will not bother with Propellant Crossfeed for Falcon Heavy; by the time the thing is well into operations, Elon will probably be into expending effort on developing the BFRs. Good uprating results for FH could come from a 'mere' upper stage upgrade.

That is a bit of a bold assumption, considering Elon specifically talked about how putting together small gains made huge differences in rocket performance. ...

It does make a difference in mass delivered to orbit per launch ... but the number that SpaceX is most concerned with from the Falcon line is probably revenue, at this point, so let's not forget Gwynne Shotwell's recent remark that they're not going to do crossfeed until they have a customer for it.  There just aren't a whole lot of single payloads that big waiting for a launch vehicle.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/20/2016 05:16 pm
Once Raptor is developed, it might be easier to build and launch BFR with reusable second stage/MCT than dealing with 3 cores and cross feed.  Three cores might be ok without cross as far as complications. 

From the chart it seems the best overall is either expend all cores (previously flown) or save the side boosters on ASDS and expend the core (previously flown).  It is all going to depend on how many times a core can re-fly.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GreenShrike on 04/20/2016 05:31 pm
I think we're all learning the ASDS recovery is less reliable...

I know SpaceX says they expect to lose a third of ASDS recoveries, but I think that's just sandbagging.

It isn't that ASDS recoveries are unreliable, it's that F9 *itself* has been unreliable.

What it comes down to is that there have been four ASDS failures and one success. However, the failures have been flaws with the rocket and having nothing to do with ASDS bargings themselves.

Running out of hydraulic fluid has been addressed, and with each additional flight they get more statistical data about how much fluid is actually required. A sticky valve shouldn't happen again as SpaceX will know to test for them. A leg failing to lock will be mitigated via a design change or via preventing ice buildup in the critical areas.

Only SES-9 fell under the "everything was fine with the rocket and it still failed" category, except that even then, the rocket was going flat out with every margin carved to the bone and beyond. Lesson learned: 5.3t plus ASDS recovery is beyond F9 v1.2's means, so either F9 gets improved a few more percent until 5.3t is within capability, or SpaceX sells FH 3-RTLS rides to 5.3t sats and above.

The successful landings -- including Jason's ultimate failure, as it did touch down successfully -- have so far shown that when the rocket doesn't suffer some sort of mechanical failure and has sufficient margin, F9 lands on the barge just fine.

If they add sea state at the ASDS to the standard launch contract's list of acceptable launch conditions so the client won't complain if a launch is scrubbed due to 10m swells, and choose the vehicle and recovery options as necessary to ensure sufficient margin for recovery, then ASDS bargings should become as routine as LZ-1 landings.

...and much more intensive.

Though granted said routine will remain more intensive than LZ-1 landings. ;-)

The proof will be in whether SpaceX prefers to sell F9 ASDS flights or FH 3-RTLS flights for 5t+ sats in the future. I suspect the risk during an ASDS will be minimal and that refurbishing, prepping and fueling a single core while factoring in the additional risk of an ASDS recovery will still be less expensive than the refurb/refuel/prep of a 3-core Falcon Heavy launch campaign, with the inherent risk of more engines and separation events to roll the dice on during flight, even if all three end up landing at LZ-1.

If I'm wrong, then F9 would mostly be used in RTLS mode, and there'll be a lot more FH flights.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 04/20/2016 05:41 pm
For the sake of argument. If you add a Raptor US [210mt prop, 375 vac ISP, 10mt dry weight] then here is the ball park LEO capabilities for the different recovery options that would result for FH: (Note the Raptor US also delivers for each case >10% more DV to account for the lower DV supplied by the 1st stages)

3 RTLS - 42
2 RTLS center ASDS - 50
3 ASDS - 59
2 RTLS center Expended - 70
2 ASDS center Expended - 75
3 Expended - 90

So why spend time developing the crossfeed further when there maybe an easier answer for more performance that also is in the direction of tech for the BFR\MCT.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 04/20/2016 05:45 pm
For the sake of argument. If you add a Raptor US [210mt prop, 375 vac ISP, 10mt dry weight] then here is the ball park LEO capabilities for the different recovery options that would result for FH: (Note the Raptor US also delivers for each case >10% more DV to account for the lower DV supplied by the 1st stages)

3 RTLS - 42
2 RTLS center ASDS - 50
3 ASDS - 59
2 RTLS center Expended - 70
2 ASDS center Expended - 75
3 Expended - 90

So why spend time developing the crossfeed further when there maybe an easier answer for more performance that also is in the direction of tech for the BFR\MCT.

But where that Raptor US really shines is in the increased payloads to higher energy targets!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GORDAP on 04/20/2016 05:47 pm
It's not that it isn't a good idea, just that the BFR development may well overtake it, and mean F9H crossfeed is unnecessary.
It amazes me that people think that the same SpaceX that is struggling to get the FH to the launchpad can somehow magically snap their fingers and conjure up the BFR, a whole new rocket with new engines that is bigger than anything anybody has ever launched before.  With new bigger infrastructure, new bigger environmental hurdles...

Yeah, crossfeed sounds really tough compared to that.

I think cross feed is an exciting idea and I could see it being developed for one key benefit. Allowing the central core do RTLS vs ASDS.

The fuel requirements and burn times for a central core RTLS will be significant and I think we're all learning the ASDS recovery is less reliable and much more intensive. 

Wannamoon, doesn't crossfeed make it less likely to do RTLS (vs ASDS), rather than more likely?  If I understand crossfeed correctly, they will be powering 6 of the central core's Merlins from the outer tanks during the initial boost phase, which empties the side cores earlier, but leaves nearly a full central core at time of side core separation.  Thus the central core is able to burn longer, and staging with S2 is done at a higher velocity, and further downrange - both of which make RTLS harder, not easier.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 04/20/2016 06:03 pm
It's not that it isn't a good idea, just that the BFR development may well overtake it, and mean F9H crossfeed is unnecessary.
It amazes me that people think that the same SpaceX that is struggling to get the FH to the launchpad can somehow magically snap their fingers and conjure up the BFR, a whole new rocket with new engines that is bigger than anything anybody has ever launched before.  With new bigger infrastructure, new bigger environmental hurdles...

Yeah, crossfeed sounds really tough compared to that.

I think cross feed is an exciting idea and I could see it being developed for one key benefit. Allowing the central core do RTLS vs ASDS.

The fuel requirements and burn times for a central core RTLS will be significant and I think we're all learning the ASDS recovery is less reliable and much more intensive. 

Wannamoon, doesn't crossfeed make it less likely to do RTLS (vs ASDS), rather than more likely?  If I understand crossfeed correctly, they will be powering 6 of the central core's Merlins from the outer tanks during the initial boost phase, which empties the side cores earlier, but leaves nearly a full central core at time of side core separation.  Thus the central core is able to burn longer, and staging with S2 is done at a higher velocity, and further downrange - both of which make RTLS harder, not easier.
It comes down to what is more likely a Raptor US or a FH 1st stage crossfeed configuration?

Crossfeed increases the complexity of the booster staging and the three cores plumbing making them no longer common to the F9. Plus there would also be two defineting plumbing version the boosters and center core.

An Raptor Vac based US requires a Raptor Vac engine which is currently under development with a prototype (test article) to be completed sometime in late 2017. A US design using the Raptor is not a difficult task. But the capability to manufacture a 5m tank may prove the most challenging and biggest hurdle for a Raptor US. Also the FH pad would require additional plumbing for the liquid methane. Such a large US sized for use on the FH would not be suitable for the F9. F9 with M1D US and FH with Raptor US with only the 1st stages common between them.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 04/20/2016 06:07 pm
So why spend time developing the crossfeed further when there maybe an easier answer for more performance that also is in the direction of tech for the BFR\MCT.
How is developing an entirely new upper stage with a new fuel and a new engine easier than cross-feed?  I honestly don't get this assessment.  It's like cross-feed is the most impossible thing ever conceived of by man.

I can agree it is "in the direction of BFR"... sort of... in the sense that the fuel and engine are presumably the same.  However the upper stage itself would still be new.

What am I missing?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 04/20/2016 06:09 pm
Crossfeed increases the complexity of the booster staging and the three cores plumbing making them no longer common to the F9. Plus there would also be two defineting plumbing version the boosters and center core.
I don't think that is necessarily true (lack of commonality).  And the boosters and center core are already different, so that doesn't seem like a big deal to me.

If it is true, that would be a deal-breaker.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 04/20/2016 06:17 pm
I think we're all learning the ASDS recovery is less reliable...

I know SpaceX says they expect to lose a third of ASDS recoveries, but I think that's just sandbagging.

It isn't that ASDS recoveries are unreliable, it's that F9 *itself* has been unreliable.

What it comes down to is that there have been four ASDS failures and one success. However, the failures have been flaws with the rocket and having nothing to do with ASDS bargings themselves.

Running out of hydraulic fluid has been addressed, and with each additional flight they get more statistical data about how much fluid is actually required. A sticky valve shouldn't happen again as SpaceX will know to test for them. A leg failing to lock will be mitigated via a design change or via preventing ice buildup in the critical areas.

Only SES-9 fell under the "everything was fine with the rocket and it still failed" category, except that even then, the rocket was going flat out with every margin carved to the bone and beyond. Lesson learned: 5.3t plus ASDS recovery is beyond F9 v1.2's means, so either F9 gets improved a few more percent until 5.3t is within capability, or SpaceX sells FH 3-RTLS rides to 5.3t sats and above.

The successful landings -- including Jason's ultimate failure, as it did touch down successfully -- have so far shown that when the rocket doesn't suffer some sort of mechanical failure and has sufficient margin, F9 lands on the barge just fine.

If they add sea state at the ASDS to the standard launch contract's list of acceptable launch conditions so the client won't complain if a launch is scrubbed due to 10m swells, and choose the vehicle and recovery options as necessary to ensure sufficient margin for recovery, then ASDS bargings should become as routine as LZ-1 landings.

...and much more intensive.

Though granted said routine will remain more intensive than LZ-1 landings. ;-)

The proof will be in whether SpaceX prefers to sell F9 ASDS flights or FH 3-RTLS flights for 5t+ sats in the future. I suspect the risk during an ASDS will be minimal and that refurbishing, prepping and fueling a single core while factoring in the additional risk of an ASDS recovery will still be less expensive than the refurb/refuel/prep of a 3-core Falcon Heavy launch campaign, with the inherent risk of more engines and separation events to roll the dice on during flight, even if all three end up landing at LZ-1.

If I'm wrong, then F9 would mostly be used in RTLS mode, and there'll be a lot more FH flights.

I'm not arguing the choice between F9 v FH.  Just a strong preference for RTLS when possible. 

No question they are improving the ASDS operations. But it will always be higher risk and more expensive.  Plus sea conditions can potential prevent recovery or postpone launch. 

A week to get a stage back in a hangar does not help the 'rapid' reuse. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GreenShrike on 04/20/2016 06:40 pm
The existing very marginal manifest for FH,

Falcon Heavy has yet to fly, and the unfortunate fact of the matter is that SpaceX has been slipping its first launch for years. I rather think those facts would make a client somewhat hesitant gamble a flagship comsat's launch on an unflown rocket. Instead, the client would book a single launch, to show support to the new entrant (competition is always good), and to guarantee a cheap launch slot for whenever the vehicle does fly.

That hesitation would evaporate, of course, once it flies, and there are sufficient flights manifested such that it will have demonstrated sufficient reliability to be seriously considered by the time future comsats require a launch vehicle, especially as the only thing "diminutive" about FH is its relative price, and Proton demonstrates that a semi-unreliable launcher can win contracts if its cheap enough.

as well as lack of candidate payloads for FH show it to be diminutive to SpaceX's overall current & future cash flow.   If it remains diminutive after FH's first few flights & fails to win launch contracts away from Ariane & Atlas in the +6.5t to GTO category,

First, you forgot Proton. The current heavy comsat market is split between Ariane 5 and Proton, and if FH only manages to eat Proton's lunch, FH will still launch regularly.

However, I do think I see your actual problem: FH won't be competing only for 6.5t+ comsats. Its market is rather larger than that.

Ignoring the plainly obvious uses to which SpaceX itself likely plans to put the Falcon Heavy, the comsat market that FH will be going after is more like 5 tonnes+, a rather wider swath than the rarer 6.5t+ birds.

While comsats up to, what, 6t or so? can be launched on the Falcon 9,  SES-9's booster demonstrated fairly emphatically upon OCISLY's deck that 5.3t is beyond what F9 can lift while recovering its booster stage.

Since one would have to be very out-of-the-loop to not understand that SpaceX wants to recover all booster cores it possibly can, and desires to splash in the ocean as close to zero as possible, it therefore seems fairly reasonable to assume that rather than simply ignoring the market for comsats between, say, 5 or 5.2t and ~6.8t, SpaceX will instead bid a FH to fly them, and recover all three cores, probably via RTLS as, according to Nadrek above, an ASDS won't be needed until ~7t needs to be lofted to GTO.

Unless SpaceX starts dual-launching, I guess, which I believe SpaceX has said it was going to stay away from, since Arianespace finds it to be a real PITA scheduling-wise.

As such, in the future I think F9 will only be used to lift light to medium-weight sats and thence be recovered, even if when operated expendably it may in fact be a heavy-class launcher, and instead Falcon Heavy will be SpaceX's workhorse vehicle, launching the more expensive intermediate and heavy-weight sats, the exact opposite of being "diminutive to SpaceX's overall [...] future cash flow".

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Craig_VG on 04/21/2016 12:12 am
[....]

Hi, while SES-9 was a very heavy sat, it is important to note that it was launched in a way to get it on station sooner, requiring a multiple seconds longer stage 1 burn. If SpaceX were to launch another sat of the same mass landing would be easier if not for the special case of SES-9 needing to get on station so quickly.


This was incorrect, only the second stage was affected, as per my own post:

http://forum.nasaspaceflight.com/index.php?topic=39348.msg1494793#msg1494793


Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/21/2016 12:45 am
It's not that it isn't a good idea, just that the BFR development may well overtake it, and mean F9H crossfeed is unnecessary.
It amazes me that people think that the same SpaceX that is struggling to get the FH to the launchpad can somehow magically snap their fingers and conjure up the BFR, a whole new rocket with new engines that is bigger than anything anybody has ever launched before.  With new bigger infrastructure, new bigger environmental hurdles...

Yeah, crossfeed sounds really tough compared to that.

I think cross feed is an exciting idea and I could see it being developed for one key benefit. Allowing the central core do RTLS vs ASDS.

The fuel requirements and burn times for a central core RTLS will be significant and I think we're all learning the ASDS recovery is less reliable and much more intensive. 

Wannamoon, doesn't crossfeed make it less likely to do RTLS (vs ASDS), rather than more likely?  If I understand crossfeed correctly, they will be powering 6 of the central core's Merlins from the outer tanks during the initial boost phase, which empties the side cores earlier, but leaves nearly a full central core at time of side core separation.  Thus the central core is able to burn longer, and staging with S2 is done at a higher velocity, and further downrange - both of which make RTLS harder, not easier.
It comes down to what is more likely a Raptor US or a FH 1st stage crossfeed configuration?

Crossfeed increases the complexity of the booster staging and the three cores plumbing making them no longer common to the F9. Plus there would also be two defineting plumbing version the boosters and center core.
They are no longer common anyway.

Quote
An Raptor Vac based US requires a Raptor Vac engine which is currently under development with a prototype (test article) to be completed sometime in late 2017. A US design using the Raptor is not a difficult task. But the capability to manufacture a 5m tank may prove the most challenging and biggest hurdle for a Raptor US. Also the FH pad would require additional plumbing for the liquid methane. Such a large US sized for use on the FH would not be suitable for the F9. ...
This isn't true. The only reason it could be true is if the stage was under-thrust to serve as a second stage, which is unlikely since it will be Raptor-powered (and Raptor will likely be much more thrust than is strictly needed). A large upper stage would mean a lower staging velocity for the first stage, which is a good thing. At worse, you might cause the first stage to have lower thrust than you'd really like for lift-off, but you could address that by at very least not fully loading the first stage, though the Merlins doubtless have plenty of thrust and could handle a slight tweak to improve thrust even further.

Also, a Raptor-based stage would probably be only done if it enabled a reusable upper stage. And that would be a very good thing for both F9 and Falcon Heavy, and would retire a heck of a lot of huge risks for BFR and BFS (and Mars EDL). The extra plumbing is an annoyance, but they'll have to familiarize themselves with methane ground support equipment anyway for BFR/BFS. And a slightly larger tank is also an annoyance, but not dramatically so. I'd say the likely reuse hardware is a much, MUCH greater challenge. And I just can't see SpaceX bothering with a dramatically new stage without trying to incorporate reuse.

Additionally, the Air Force Raptor contract mentions the Raptor would be for an upper stage engine for BOTH Falcon Heavy AND Falcon 9, which again contradicts your claim that a Raptor stage wouldn't be suitable for both Heavy and 9.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/21/2016 03:04 am
Methane is not that big a problem.  Natural gas can be piped in then liquefied.  The same type equipment, valves, etc, are in the same category as LOX, since they are about the same temperature, unlike liquid hydrogen.  I hope they can get a Raptor upper stage developed soon after the Raptor upper stage engine in 2017.  This will be another milestone for SpaceX, before BFR and MCT. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MATTBLAK on 04/21/2016 03:34 am
How wide would a Raptor upper stage be for Falcon 9 or FH? Would about 5.2 meters be a good guess to match their largest payload fairing?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 04/21/2016 08:09 am
It's not that it isn't a good idea, just that the BFR development may well overtake it, and mean F9H crossfeed is unnecessary.
It amazes me that people think that the same SpaceX that is struggling to get the FH to the launchpad can somehow magically snap their fingers and conjure up the BFR, a whole new rocket with new engines that is bigger than anything anybody has ever launched before.  With new bigger infrastructure, new bigger environmental hurdles...

Yeah, crossfeed sounds really tough compared to that.

It amazes me that people don't read posts accurately. "BFR development MAY overtake it", not "WILL overtake it".

My own opinion is that BFR is some years away, but so is crossfeed, and that is gated by whether crossfeed actually turns out to be needed. F9H with FT mods may cover the market already.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/21/2016 01:17 pm
It has been mentioned and figured at 5.2m the same length as the existing second stage and the same diameter as the fairing.  This would give an adequate supply of metholox for the second stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 04/21/2016 01:54 pm
It amazes me that people don't read posts accurately.
That's pretty hilarious, because you clearly misread my post.  I don't believe there is any chance of what you wrote happening.  (With the exception that if crossfeed never happens, BFR would clearly "overtake" it if and when it happens).

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 04/21/2016 02:34 pm
How wide would a Raptor upper stage be for Falcon 9 or FH? Would about 5 meters be a good guess to match their largest payload fairing?

The estimated size of the nozzle is 4.8 meter diameter.   So it's going to look like a grapefruit on a toothpick. 

The interstate is going to be a serious piece of structural engineering.

With the increased loads on the first stage I imagine it will be a structural redesign.  I don't think it's an easy plug and play. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Nomadd on 04/21/2016 02:52 pm
Methane is not that big a problem.  Natural gas can be piped in then liquefied.  The same type equipment, valves, etc, are in the same category as LOX, since they are about the same temperature, unlike liquid hydrogen.  I hope they can get a Raptor upper stage developed soon after the Raptor upper stage engine in 2017.  This will be another milestone for SpaceX, before BFR and MCT. 
Methane and natural gas aren't the same thing. Even if the engines could tolerate some ethane, I'd assume the ratio would have to be constant, which doesn't always happen with public gas supplies. Natural gas can also have some propane, butane and pentane in the mix.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomTX on 04/21/2016 02:56 pm
Methane is not that big a problem.  Natural gas can be piped in then liquefied.  The same type equipment, valves, etc, are in the same category as LOX, since they are about the same temperature, unlike liquid hydrogen.  I hope they can get a Raptor upper stage developed soon after the Raptor upper stage engine in 2017.  This will be another milestone for SpaceX, before BFR and MCT. 
Methane and natural gas aren't the same thing. Even if the engines could tolerate some ethane, I'd assume the ratio would have to be constant, which doesn't always happen with public gas supplies. Natural gas can also have some propane, butane and pentane in the mix.

Okay, it can be trucked in and liquefied. Still NBD for equipment.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomTX on 04/21/2016 02:59 pm
So why spend time developing the crossfeed further when there maybe an easier answer for more performance that also is in the direction of tech for the BFR\MCT.
How is developing an entirely new upper stage with a new fuel and a new engine easier than cross-feed?  I honestly don't get this assessment.  It's like cross-feed is the most impossible thing ever conceived of by man.

I can agree it is "in the direction of BFR"... sort of... in the sense that the fuel and engine are presumably the same.  However the upper stage itself would still be new.

What am I missing?

"Easier" in the sense that they need a testbed for methane and  Raptor anyway. Most of the effort will be spent one way or the other, may as well end up with a Raptor 2nd stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 04/21/2016 03:06 pm
It amazes me that people don't read posts accurately.
That's pretty hilarious, because you clearly misread my post.  I don't believe there is any chance of what you wrote happening.  (With the exception that if crossfeed never happens, BFR would clearly "overtake" it if and when it happens).

Ha bloody ha.

No I didn't misread your post. If you read my post, I never said it was going to happen either, just that there is chance that it might before crossfeed is needed. That's the bit you missed. And before you go on about it, I'm done with this bit.

I suspect crossfeed will never happen though, as the F9HFT won't need it for current generation payloads, and they will get droneship landing sorted out.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 04/21/2016 03:10 pm
No I didn't misread your post. If you read my post, I never said it was going to happen either, just that there is chance that it might before crossfeed is needed.
There.  Is.  No.  Chance.  Zero percent.  Nada.  Not going to happen.  That is what I am saying.  I am saying that "may" happen is wrong.  I did not misread what you wrote, I disagree with it.
Quote
I suspect crossfeed will never happen though, as the F9HFT won't need it for current generation payloads, and they will get droneship landing sorted out.
Well, that is certainly possible.  We need to see FH even fly before crossfeed is a consideration.  There may never be a payload that needs crossfeed.  I am not convinced it will ever happen either.  But if it does happen (if there is a need), it will happen before BFR, no doubt about it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/21/2016 03:18 pm
I think they will just be getting FH flying a few times, and by that time they may be able to have the Raptor upper stage.  Therefore no crossfeed will be needed.  Also if this new upper stage is re-usable it may be re-fueled with a stretched upper stage in orbit by using used boosters in expendable mode so they can deliver more fuel to orbit, for testing the re-usable upper stage in a moon landing and return scenario.  This would work out bugs before building MCT. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/21/2016 04:10 pm
I could see cross-feed happening if NASA receives direction from a new congress/administration to cancel SLS/Orion and focus on Luna while SpaceX focuses on Mars.

FH with Raptor US, in either recoverable or reusable mode, would be far preferable to SLS/Orion for a Lunar program. I could see SpaceX developing cross-feed for NASA under these circumstances.

Natural gas is almost always 95% methane. Other hydrocarbons included are ethane, propane, butane, iso butane, pentane, iso pentane, and five isomers of hexane. Then you have Nitrogen, Carbon Dioxide, water, Hydrogen Sulfide, and possibly Helium, all of which are inert or toxic.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/21/2016 05:00 pm
I think also when you liquefy it, the other gases will evaporate or be so diluted that it really wouldn't matter. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 04/21/2016 05:16 pm
I think also when you liquefy it, the other gases will evaporate or be so diluted that it really wouldn't matter.

Pipeline quality natural gas is typically 95% methane, 3% ethane, and 1% N2 with >>1% of other gases. ethane will liquefy first at 184K, then methane at 111K, and both can be subcooled to about 90K at 1 atm before solidifying.

If necessary, ethane can be condensed off during liquefaction. I imagine it will burn clean enough to run LNG instead of pure methane though.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/21/2016 05:44 pm
I think also when you liquefy it, the other gases will evaporate or be so diluted that it really wouldn't matter.

No, they will not evaporate. Liquification happens in a closed tank and these things all obey the Ideal Gas Law. To where will they evaporate in a closed system? They are all in gaseous form to begin with. Your statement that they are going to evaporate implies that the gasses are going to liquefy and then re-gasify. That is only going to happen while adjusting the temperature and pressure, which means you are already in the process of refining and distilling the various compounds and isomers. Removing substances should be very similar to grading out petroleum in a refinery, except that you are doing so at cryogenic temperatures.

We have been using KeroLox engines for many decades. The linked page is a recent Stanford PhD Mechanical Engineering/Chemistry dissertation. The topic regards the almost endless steps of oxidation of compounds that occur in an RP-1 burning rocket engine. Even with all the years of previous research available to her, the author was not able to quantify and qualify everything to exact measurement. We are still at the very beginning of quantitative and qualitative analysis of all steps of CH4 oxidation in a full-flow staged-combustion rocket engine. Refining NG to CH4 only is going to make our understanding of the chemistry, and our ability to design such an engine far more thorough as opposed to throwing 16 other substances, whose mixture is never the same proportion, into the mix.

Dissertation: http://hanson.stanford.edu/dissertations/MacDonald_2012.pdf
Related Research Data: http://www.dtic.mil/dtic/tr/fulltext/u2/a533333.pdf
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gospacex on 04/21/2016 06:14 pm
Regarding crossfeed. How about "top-feed"? Mount a LOX tank on top of one side booster of FH, and a RP-1 tank on top of the another. Pipe them to the corresponding tanks of the core booster. Pump these propellants into core booster during 1st stage flight.

Hydrostatic pressure during 1st stage flight should be helping a lot with pumping.

Side boosters need no modifications if they are the same as stock F9 1st stage. They are already designed to carry some weight on top.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GalacticIntruder on 04/21/2016 06:20 pm
I think a long duration capable upper stage with Raptor (ex. ACES), and reusable, would be the priority of SpaceX over their Crossfeed FH.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/21/2016 06:27 pm
I was thinking nitrogen and CO2 might not liquefy at methane temps.  Also, ethane will burn, so only about 2% will not burn.  It isn't perfect 100%, but trying to get out the 2% might not be cost effective.  I worked in the natural gas pipeline industry for 39 years.  At "city gate" stations is where they put in the odorant which is about 1%.  Straight pipeline gas is not odorized.  I'm sure there is a main pipeline going down the east Florida coast that can be tapped for natural gas.  We also liquefied it and stored it in summer for release in winter.  Most of the natural gas infrastructure is in place, so obtaining it and storing it isn't that big a problem.  We stored it in giant "thermos" tanks that had an inside storage tank and 3' away was the outside wall.  A vacuum was pulled between the two to keep the gas liquid and maintained.  We also had equipment to re-liquefy boil-off.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/21/2016 06:31 pm
You are right, I think a modified second stage with long duration equipment would be great for an ACES type fuel depot, probably a stretched second stage since it would be it's own payload.  We would then have one ACES type metholox stage and the ULA ACES stage with hydrolox for two alternative methods depending on payload and duration.  Metholox being warmer than hydrolox for storage and a heavier molecule would be easier to maintain long duration boil-off. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: the_other_Doug on 04/21/2016 06:32 pm
Regarding crossfeed. How about "top-feed"? Mount a LOX tank on top of one side booster of FH, and a RP-1 tank on top of the another. Pipe them to the corresponding tanks of the core booster. Pump these propellants into core booster during 1st stage flight.

Hydrostatic pressure during 1st stage flight should be helping a lot with pumping.

Side boosters need no modifications if they are the same as stock F9 1st stage. They are already designed to carry some weight on top.

Different densities, and the engines use the two liquids at different rates, so one side would be heavier than the other.  I don't think that would be a fixable problem.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/21/2016 06:37 pm
Like everyone said, with a metholox Raptor based upper stage, cross-feed might not be needed for a long time, UNLESS SLS is cancelled like someone said and NASA helps fund the cost of cross-feed and pays SpaceX for an expendable 90 ton launch if and when 90 tons will be needed.  40, maybe 50 tons with a fully re-useable FH Raptor based upper stage can get a lot of things into orbit.  That is twice the existing single rocket capabilities.  We just need to get FH launched, hopefully late this year. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 04/21/2016 06:40 pm
I was thinking nitrogen and CO2 might not liquefy at methane temps.  Also, ethane will burn, so only about 2% will not burn.  It isn't perfect 100%, but trying to get out the 2% might not be cost effective.  I worked in the natural gas pipeline industry for 39 years.  At "city gate" stations is where they put in the odorant which is about 1%.  Straight pipeline gas is not odorized.  I'm sure there is a main pipeline going down the east Florida coast that can be tapped for natural gas.  We also liquefied it and stored it in summer for release in winter.  Most of the natural gas infrastructure is in place, so obtaining it and storing it isn't that big a problem.  We stored it in giant "thermos" tanks that had an inside storage tank and 3' away was the outside wall.  A vacuum was pulled between the two to keep the gas liquid and maintained.  We also had equipment to re-liquefy boil-off.

Spacenut we had this discussion a while back it is not 1% odorant, where you get your 1% number is that the specification for odorant is that a concentration of 1% of leaked gas must be detectable. The products used in general are detectable at a concentration of 0.1 parts per billion so if 1% of gas must be detectable then you need 10 parts per billion in the pipeline gas that is 0.000001% concentration in the pipeline.

http://cdn.intechopen.com/pdfs/11460.pdf (http://cdn.intechopen.com/pdfs/11460.pdf)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/21/2016 06:47 pm
We always called it 1% with our gauges, you are right, but it isn't really relevant to un-odorized gas for rocket fuel.  I just think there are a lot of everyday people on these threads that are interested in space, but may associate odorized natural gas they get at their homes with the rocket fuel. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/21/2016 08:38 pm
I was thinking nitrogen and CO2 might not liquefy at methane temps.  Also, ethane will burn, so only about 2% will not burn.  It isn't perfect 100%, but trying to get out the 2% might not be cost effective.  I worked in the natural gas pipeline industry for 39 years.  At "city gate" stations is where they put in the odorant which is about 1%.  Straight pipeline gas is not odorized.  I'm sure there is a main pipeline going down the east Florida coast that can be tapped for natural gas.  We also liquefied it and stored it in summer for release in winter.  Most of the natural gas infrastructure is in place, so obtaining it and storing it isn't that big a problem.  We stored it in giant "thermos" tanks that had an inside storage tank and 3' away was the outside wall.  A vacuum was pulled between the two to keep the gas liquid and maintained.  We also had equipment to re-liquefy boil-off.

I would expect them to super chill L-CH4 to around -290F. Liquid Nitrogen would likely just be vented off the top, never liquefying or re-gasifying, because it boils at -321F. One significant problem would seem to be CO2. Carbon Dioxide has no liquid state at STP (standard temperature and pressure). It's sublimation point between gaseous and solid states at STP is -109.3F. This means that at some level in the stratification of differing substances, you are going to have a planar disc of dry ice floating among the liquids. Even if you stir it, you have slush crystals floating in the mix, so that's more you have to get rid of. All of the hydrocarbons that remain have lower ISP than methane. Water, Helium, etc. are wasted mass.

We are talking about an ultra-advanced spaceship that costs many billions of dollars, but you don't want to spend a few thousand to get rid of impurities in the fuel and boost it to max. ISP? Gosh, they spend so much more tweeking other stuff for tiny performance gains. Being so lazy as not to get this junk out of the fuel is..................well, I feel sure they will refine it to pure methane.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Meltro on 04/21/2016 08:55 pm
So I have redone the table and made a graphic of it so that it can retain formatting.  Scenarios with all the cores returned have no shading, centre core expendables are yellow, all core expendables are red.

Sorry if this was already mentioned but, for the non-crossfeed scenarios, what burn profile are you using for the center booster?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GalacticIntruder on 04/21/2016 09:34 pm
SpaceX has never stated how pure they want or need their methane. Easily obtainable bulk methane is at least 99 percent pure CH4, with a tiny bit of H2O, N2, O2, CO2. N2 being the most of the contaminants, like 2000ppm, and CO2 being at 100pm. They could get ultra pure CH4 at 99.97 pure, or even research grade at 99.999 percent pure. But something that special  might not be practical for the volumes needed for their rockets.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/21/2016 09:43 pm
CO2 is normally heavy, methane is about 0.6 specific gravity.  Does it still float frozen? 

In a large tank of LNG, to get pure methane, they should be able to just pump from the middle of the tank.  We had LNG tanks that were about 100-150' in diameter and about 75-100' tall.  Very little if any water should be in the natural gas.  Water and ethane can be drained off the pipeline with drip traps before making liquid.  There are large drip traps and strainers usually at every city gate station. even small amounts of water or liquid ethane can cause problems in natural gas equipment sometimes, so drips are installed.  Water can put out pilot lights.  There may be very small amounts of butane and propane also, they also are strained out using drip traps.  Seems like CO2 would be the only major problem, and as you said nitrogen could easily be vented at the top of a large tank.  Also if the LNG sits in the large storage tank for a while, the CO2 if it floats would either go to the top, and if not, the bottom.  Thus pumping it off the middle when fueling the rockets. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/21/2016 10:08 pm
CO2 is normally heavy, methane is about 0.6 specific gravity.  Does it still float frozen? 

In a large tank of LNG, to get pure methane, they should be able to just pump from the middle of the tank.  We had LNG tanks that were about 100-150' in diameter and about 75-100' tall.  Very little if any water should be in the natural gas.  Water and ethane can be drained off the pipeline with drip traps before making liquid.  There are large drip traps and strainers usually at every city gate station. even small amounts of water or liquid ethane can cause problems in natural gas equipment sometimes, so drips are installed.  Water can put out pilot lights.  There may be very small amounts of butane and propane also, they also are strained out using drip traps.  Seems like CO2 would be the only major problem, and as you said nitrogen could easily be vented at the top of a large tank.  Also if the LNG sits in the large storage tank for a while, the CO2 if it floats would either go to the top, and if not, the bottom.  Thus pumping it off the middle when fueling the rockets.

O.K., so now we're talking about simple ways to get a much more refined fuel. This is far, far better than the 95% pure that comes out of the well.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/21/2016 10:15 pm
That is why I think some people are overthinking getting to pure methane.  It shouldn't be as complicated as it seems.  How do they get pure liquid oxygen out of the air without frozen water, or there again frozen CO2?  Then there is nitrogen in the atmosphere.  They can fill a Falcon 9 in what? about 30 minutes, with liquid oxygen.  The equipment must not be that complicated to make it.  It may use a lot of power during manufacture, but that is to be expected. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sanman on 04/21/2016 10:23 pm
Since SpaceX has already pursued Propellant Densification for Falcon FT, is it reasonable to assume that this would be also be there for FalconHeavy? If so, then will it pose any complications for cross-feed?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 04/21/2016 11:02 pm
Liquid oxygen is made in a process that's pretty similar to fractional distillation except in reverse... it takes advantage of the different liquefaction temperatures of O2 and N2 (and the rest of the trace gases)[1]

I expect that if you take pipeline gas that is already at 95% pure methane and do some cooling to just the right temperatures, in stages, with taps, you can get a lot closer to 100% pure methane without a lot of work... and done right the methane you are getting never gets warmed up again, it goes straight from there into your storage tanks.

But SpaceX may want to make Raptor not so picky about exactly what it's running on as ISRU methane is likely to have contaminants of various sorts too.

1 - see https://en.wikipedia.org/wiki/Cryogenic_oxygen_plant
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/21/2016 11:51 pm
Yep, cooler gas gets rid of water and liquids quicker in the traps.  It usually goes through an orifice and it gets cooled down.  Sometimes when this is done, ice forms on the pipe downstream of the orifice. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/22/2016 12:05 am
But SpaceX may want to make Raptor not so picky about exactly what it's running on as ISRU methane is likely to have contaminants of various sorts too.

Good point.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: robert_d on 04/22/2016 12:37 am
Like everyone said, with a metholox Raptor based upper stage, cross-feed might not be needed for a long time, UNLESS SLS is cancelled like someone said and NASA helps fund the cost of cross-feed and pays SpaceX for an expendable 90 ton launch if and when 90 tons will be needed.  40, maybe 50 tons with a fully re-useable FH Raptor based upper stage can get a lot of things into orbit.  That is twice the existing single rocket capabilities.  We just need to get FH launched, hopefully late this year.
If SLS did get cancelled, then I think there would be a reason to consider a 'Falcon Four Core'. Two reasons: It would allow the volume for either a two merlin second stage or a single engine methane powered version. Also it would allow a larger (likely elliptical) payload fairing. Looks like 27 x 18 would be possible. The middle 'dual core' would launch and land as one unit, so launch operations would not be doubled in complexity.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 04/22/2016 12:55 am
But SpaceX may want to make Raptor not so picky about exactly what it's running on as ISRU methane is likely to have contaminants of various sorts too.

Good point.
That's not to say you wouldn't want to use the best performing mixture when launching from Earth, because why not? You have the industrial base to get the mixture just the way you want it.... just that you should be able to run, somewhat degraded, on less precise mixtures when launching from Mars. As discussed in many threads before, it's actually not such a hard problem given the much lower gravity losses and lower launch weight since you're returning partly unladen. 

By the time you're launching as heavily laden from Mars you are likely to have a more robust industrial base there that can produce higher purity methane...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/22/2016 02:00 am
It amazes me that people don't read posts accurately.
That's pretty hilarious, because you clearly misread my post.  I don't believe there is any chance of what you wrote happening.  (With the exception that if crossfeed never happens, BFR would clearly "overtake" it if and when it happens).
Um, you do realize that with the sentence I bolded, you two are in violent agreement? That's what /I/ find fake-hilarious.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gospacex on 04/22/2016 12:50 pm
Regarding crossfeed. How about "top-feed"? Mount a LOX tank on top of one side booster of FH, and a RP-1 tank on top of the another. Pipe them to the corresponding tanks of the core booster. Pump these propellants into core booster during 1st stage flight.

Hydrostatic pressure during 1st stage flight should be helping a lot with pumping.

Side boosters need no modifications if they are the same as stock F9 1st stage. They are already designed to carry some weight on top.

Different densities, and the engines use the two liquids at different rates, so one side would be heavier than the other.

Yes, I know that. Merlins use at least twice as much LOX than RP-1. Thankfully, LOX is also denser, which is easily seen on the landed F9 1st stage - the LOX and RP-1 tanks are roughly the same size. Therefore "top-feed" tanks can also be the same size.

Quote
I don't think that would be a fixable problem.

You did not explain why it's unfixable.

FH does not require precisely matched masses of the side boosters, the system must be able to tolerate some imbalance even now.

I imagine small variations are countered by steering, and if SpaceX wants to have engine-out capability on FH, they already work on countering larger imbalance by throttling engines.

Let's say we have 40 ton "top-feed" LOX tank and 20 ton RP-1 one. For ~450 ton side boosters, the difference in weight of 20 tons is less than 5% difference in thrust, whereas losing one Merlin-1 would be a 11% difference.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/22/2016 01:12 pm
The remaining Merlin engines can be gimbaled to compensate for the offset thrust.  The fuel and lox can't.  Lox is heavy, kerosene is lighter than water.  It would be easier and lighter just to make the upper stage wider and maybe feed some from it. The could also run the center core at lower thrust with side boosters running at full thrust, which is what I think they are going to do now.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gospacex on 04/22/2016 01:53 pm
Top-fill tanks can be made fully symmetrical if both sides carry both LOX and RP-1 tanks. This would harm mass fraction and require more piping, though.

Or one side can carry a big LOX tank, and another side carry a RP-1 tank and a smaller LOX tank, so that their weights are equal. This allows to recoup some mass fraction, but now SpaceX will need to make two kinds of "top-fills".

I am far from being able to do a detailed assessment which of these three variants is better. :/
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 04/22/2016 02:29 pm
Regarding crossfeed. How about "top-feed"? Mount a LOX tank on top of one side booster of FH, and a RP-1 tank on top of the another. Pipe them to the corresponding tanks of the core booster. Pump these propellants into core booster during 1st stage flight.

Hydrostatic pressure during 1st stage flight should be helping a lot with pumping.

Side boosters need no modifications if they are the same as stock F9 1st stage. They are already designed to carry some weight on top.

Why?  There is no benefit.  You have increase the GLOW of the vehicle for what purpose?  Show the math.  It isn't a engineering exercise to see where one can stick propellant.

The whole point of a heavy vehicle using 3 common cores is that the central core is treated like a 2nd stage and to do it has to throttle down and/or use propellants from the boosters. 


Also, the pad would need major mods.  And the core would still need mods to accept the propellant feed.  And it is good to input fluids into the top of a tank while it is draining.  It would put loads on the hardware in the tank and splashing cryogens is not a good idea.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 04/22/2016 02:37 pm

1.  FH does not require precisely matched masses of the side boosters, the system must be able to tolerate some imbalance even now.


2.  Let's say we have 40 ton "top-feed" LOX tank and 20 ton RP-1 one. For ~450 ton side boosters, the difference in weight of 20 tons is less than 5% difference in thrust, whereas losing one Merlin-1 would be a 11% difference.

1.  Yes, it does.  They will be within a few hundred pounds of each other.

2.  5% is a big difference.   If one merlin is lost, then the other booster will shutdown a merlin
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 04/22/2016 02:38 pm

I am far from being able to do a detailed assessment which of these three variants is better. :/

There isn't one.  The whole idea is bad.

 "top feed" isn't a valid trade with cross feed because adds more propellant to the existing vehicle.   Cross feed is simpler and easier to implement for a solution that keeps the vehicles basically the same.

 "top feed" would be traded against a lengthen first stage
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 04/22/2016 03:49 pm
Adding more prop for the center 1st stage is counter reuse. Make the US bigger. Go to a dual M1DVac and 5.2m diameter tank with 2x the prop in the US would result in a tremendous improvement and also decreases the recovery reuse problems for the 3 cores. Basically a 30-50% payload gain.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 04/22/2016 04:11 pm
Center core recovery is a non-issue if the barge becomes reliable, and the jury is still out on this one.

All barge failures to date were "development failures" - not indicative of future statistics.

I agree though that top-load and longer first stage are similar, and that a bigger second stage is a good and independent option.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 04/22/2016 04:25 pm
I'm curious if we have actual performance numbers yet? I know we've made any number of very informed assumptions but has SpaceX officially listed it's LEO & GEO performance numbers yet? Gwynne mentioned this was coming weeks ago but I haven't noticed any official listings. Did I miss that? (looking for official SpaceX numbers here)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 04/22/2016 04:27 pm
Adding more prop for the center 1st stage is counter reuse. Make the US bigger. Go to a dual M1DVac and 5.2m diameter tank with 2x the prop in the US would result in a tremendous improvement and also decreases the recovery reuse problems for the 3 cores. Basically a 30-50% payload gain.

Won't raptor upper stage alleviate this problem? The US will be necessarily wider with considerably improved performance.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GWH on 04/22/2016 04:49 pm
Few months ago now.  At the time she said new numbers in a few days, which is really weird.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 04/22/2016 05:00 pm
Adding more prop for the center 1st stage is counter reuse. Make the US bigger. Go to a dual M1DVac and 5.2m diameter tank with 2x the prop in the US would result in a tremendous improvement and also decreases the recovery reuse problems for the 3 cores. Basically a 30-50% payload gain.

Agree with the bigger S2 and letting all three cores burn as much as possible before jettison for I presume RTLS?  You are essentially bypassing the conundrum of all this crossfeed, topfeed, DPL vs. RTLS trade off by putting the boost energy of all three cores into the larger S2.   Each core is pretty much equal in terms of is propellant mass it can dedicate to re-use maneuvers.

Will you also then need shorter/lighter S1 cores to accommodate the increase in S2 mass?   Basically I'm curious how/when you would want to size the three boosters for engine cutoff & staging, which affects the re-use landing choices and payload capabilities.   

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 04/22/2016 05:07 pm
Few months ago now.  At the time she said new numbers in a few days, which is really weird.
Agreed. So are these numbers not being released because they aren't sure? That would seem...odd at this stage in development. Or is there a political reason for not extolling its true capabilities. Or have they not been able to squeeze the kinds of performance out yet while still integrating reuse. Perhaps the data they are getting back from various return profiles are allowing them to dial in those additional %1 -%2 efficiencies that Elon mentioned.

All things being equal, the simple explanation is they just may not know exactly yet. Is that realistic though? I suppose. I really don't know, honest questions.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 04/22/2016 05:26 pm
Adding more prop for the center 1st stage is counter reuse. Make the US bigger. Go to a dual M1DVac and 5.2m diameter tank with 2x the prop in the US would result in a tremendous improvement and also decreases the recovery reuse problems for the 3 cores. Basically a 30-50% payload gain.

Agree with the bigger S2 and letting all three cores burn as much as possible before jettison for I presume RTLS?  You are essentially bypassing the conundrum of all this crossfeed, topfeed, DPL vs. RTLS trade off by putting the boost energy of all three cores into the larger S2.   Each core is pretty much equal in terms of is propellant mass it can dedicate to re-use maneuvers.

Will you also then need shorter/lighter S1 cores to accommodate the increase in S2 mass?   Basically I'm curious how/when you would want to size the three boosters for engine cutoff & staging, which affects the re-use landing choices and payload capabilities.

Falcon Heavy has a plenty of excess of thrust at liftoff, because the boosters are designed to each lift a 120t+ of upper stage/prop load/payload. Even with 220t of upper stage and prop, plus 90t of payload, Falcon Heavy would still have a better T/W at liftoff than Falcon 9 does... so why re-engineer the S1s?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: philw1776 on 04/22/2016 05:28 pm
I'm curious if we have actual performance numbers yet? I know we've made any number of very informed assumptions but has SpaceX officially listed it's LEO & GEO performance numbers yet? Gwynne mentioned this was coming weeks ago but I haven't noticed any official listings. Did I miss that? (looking for official SpaceX numbers here)

Months ago she said numbers would be out in a few days.
I have no idea why this imminent information release promised "real soon now" did not happen.
Did the schedule brain virus that has so infected Elon spread its infection to Gwynne?  :)
Eagerly awaiting...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/22/2016 07:13 pm
Does anyone know when the numbers will be out?  They really need to update their website. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Sesquipedalian on 04/22/2016 07:28 pm
Adding more prop for the center 1st stage is counter reuse. Make the US bigger. Go to a dual M1DVac and 5.2m diameter tank with 2x the prop in the US would result in a tremendous improvement and also decreases the recovery reuse problems for the 3 cores. Basically a 30-50% payload gain.

A 5.2 diameter stage would preclude road transport.  But this may be a tradeoff SpaceX is willing to make.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/22/2016 07:48 pm
Short distances maybe not, but it can be flown via a Super Guppy plane or shipped by barge.  All of ULA's rockets are shipped by barge to the cape.  The 5.2 might require a new manufacturing facility.  Anywhere along the Gulf coast and it could be shipped to Texas launch site or the cape, even by ship to Vandenburg.  Everything doesn't have to be shipped by road transport or rail transport.  Even if it was made a Hawthorne, it could possibly be shipped a short distance by road to a nearby airport or to a dock for shipping by boat. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 04/22/2016 08:00 pm
Adding more prop for the center 1st stage is counter reuse. Make the US bigger. Go to a dual M1DVac and 5.2m diameter tank with 2x the prop in the US would result in a tremendous improvement and also decreases the recovery reuse problems for the 3 cores. Basically a 30-50% payload gain.

Agree with the bigger S2 and letting all three cores burn as much as possible before jettison for I presume RTLS?  You are essentially bypassing the conundrum of all this crossfeed, topfeed, DPL vs. RTLS trade off by putting the boost energy of all three cores into the larger S2.   Each core is pretty much equal in terms of is propellant mass it can dedicate to re-use maneuvers.

Will you also then need shorter/lighter S1 cores to accommodate the increase in S2 mass?   Basically I'm curious how/when you would want to size the three boosters for engine cutoff & staging, which affects the re-use landing choices and payload capabilities.

Falcon Heavy has a plenty of excess of thrust at liftoff, because the boosters are designed to each lift a 120t+ of upper stage/prop load/payload. Even with 220t of upper stage and prop, plus 90t of payload, Falcon Heavy would still have a better T/W at liftoff than Falcon 9 does... so why re-engineer the S1s?

The more I thought about it, there would need to change S1.  Basically, it is what it is. ( hate the phrase, but it applies).   The new S2 is where you solve the RTLS penalties of the 3 S1 cores.   F9 S1 size is already pretty maxed out, and every launch will have some innate limit set by the S2+payload mass where three boosters burning equally, will reach a Delta-V remaining limit for the RTLS maneuver.   

The proposal really bypasses the difficult trades that crossfeed creates for RTLS, DPL, & payload to orbit, by having a better S1:S2 mass ratio for staging efficiency.  ( this is where I got caught up questioning S1 sizing)  It settles on RTLS for all three cores, no need for the more expensive and time consuming DPL.   The benefits come at the cost of making a new 5.2 m core for S2.   That cost is very arguable to accept IF you see the future of FH as having a long manifest of very heavy payloads, as well as some precursor missions to Mars & the moon.   And as already pointed out, this S2 would be sized nicely for a vacuum Raptor when it becomes available.   

It is still overkill for most comsats, but not wildly so.  Some quick sims I ran show it getting around 13-14t to GTO with all three cores returned. ( 40 tons of fuel reserved for RTLS ) , which give ample margins for experimenting with S2 reuse. 

 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/22/2016 08:32 pm
If they can get this proposed stage to returned for reuse, they can then try it for a moon mission as a moon lander/return vehicle with some in space refueling.  This could test how the larger MCT would work for Mars.  NASA might fund some of this development for a moon base. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 04/22/2016 11:32 pm
I think the FH numbers aren't out yet because there hasn't been a compelling venue.  They weren't quite ready when Gwynne gave her last talk, so she didn't release them now.  And at the moment SpaceX PR is focused on the stage return.  I think when FH gets a little closer, or there's another space conference, we'll see more FH-oriented communications.  But I don't blame their communications folks (they recently got a new communications head, didn't they) for keeping the focus on stage return right now.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: IainMcClatchie on 04/22/2016 11:53 pm
Regarding crossfeed. How about "top-feed"? Mount a LOX tank on top of one side booster of FH, and a RP-1 tank on top of the another. Pipe them to the corresponding tanks of the core booster. Pump these propellants into core booster during 1st stage flight.

Hydrostatic pressure during 1st stage flight should be helping a lot with pumping.

Side boosters need no modifications if they are the same as stock F9 1st stage. They are already designed to carry some weight on top.

I think this is the way to do it.  No pumping necessary at all... it's all done with hydrostatic pressure.  No funky transients at the inlets to the turbopumps, no relights necessary after switching the valves, and the central tank is >95% full at booster separation.

With just LOX on one side and Kerosene on the other, you're going to have a significant mass asymmetry.  I suppose that's not great, especially right at the moment of liftoff.  The obvious solution is to have both a LOX and a Kerosene tank on each side booster.  But that's more complexity.

It seems to me that an F9H with crossfeed has boosters and a core that are definitely different than the F9 first stage.  Lots in common, of course, but the cores won't be interchangeable.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/23/2016 03:39 am
....

2.  5% is a big difference.   If one merlin is lost, then the other booster will shutdown a merlin
Doubt it. More likely throttle-down of opposite-side Merlins.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 04/23/2016 06:47 am
....

2.  5% is a big difference.   If one merlin is lost, then the other booster will shutdown a merlin
Doubt it. More likely throttle-down of opposite-side Merlins.

Perhaps, but as told by some SpaceX employees, not all engines have the same throttling valve hardware installed. So unless they are designated as landing engines, they may not be able to throttle as precisely - or at all.
(the source for this was a post on Reddit, but that thread is now removed)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/23/2016 06:53 am
....

2.  5% is a big difference.   If one merlin is lost, then the other booster will shutdown a merlin
Doubt it. More likely throttle-down of opposite-side Merlins.

Perhaps, but as told by some SpaceX employees, not all engines have the same throttling valve hardware installed. So unless they are designated as landing engines, they may not be able to throttle as precisely - or at all.
You are incorrect. All F9 engines throttle down near the end of the stage-one burn (though they would not throttle-down so much if an engine were lost), so all Merlin engines are capable of significant throttling (remember that v1.0 shut down 2 engines early to achieve the same effect). You misunderstood the (L2?) source, who was referring to the highly responsive throttling of the center engine.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: IainMcClatchie on 04/23/2016 09:26 am
I don't think the Raptor will burn 100% methane.  I know liquid propane will dissolve an interesting amount of hydrogen.  I'm pretty sure liquid methane will too.  The bump in ISP is easy to get without a big change in vapor pressure at a given temperature, so they'll take it.

If anything, they might actually saturate the methane with hydrogen, as it self-pressurizes better than straight methane.  In flight, they just inject a little hot propellant back into the tank for pressurization.  The methane condenses out, the hydrogen bubbles to the top and provides pressurization, and they save the weight of an insulated pipe to the top of the fuel tank.

Hydrogen at 100 Kelvin is half the weight of methane at 400 Kelvin.  That alone saves 120+ kg in a F9-equivalent first stage fuel ullage space near burnout, something like 0.5% of empty weight.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MP99 on 04/23/2016 11:09 am


But SpaceX may want to make Raptor not so picky about exactly what it's running on as ISRU methane is likely to have contaminants of various sorts too.

Good point.
That's not to say you wouldn't want to use the best performing mixture when launching from Earth, because why not? You have the industrial base to get the mixture just the way you want it.... just that you should be able to run, somewhat degraded, on less precise mixtures when launching from Mars. As discussed in many threads before, it's actually not such a hard problem given the much lower gravity losses and lower launch weight since you're returning partly unladen. 

ISTM that many payloads will be well within the capabilities of FH.

It's possible they may spend the extra for pure methane on payloads with little margin, but slap cheaper fuel in there for payloads that are just a little beyond F9.

Sounds like the sort of cost optimisation they might move to once recovery and reuse have become routine.

Cheers, Martin
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 04/23/2016 12:41 pm
I don't think the Raptor will burn 100% methane.  I know liquid propane will dissolve an interesting amount of hydrogen.  I'm pretty sure liquid methane will too.  The bump in ISP is easy to get without a big change in vapor pressure at a given temperature, so they'll take it.

If anything, they might actually saturate the methane with hydrogen, as it self-pressurizes better than straight methane.  In flight, they just inject a little hot propellant back into the tank for pressurization.  The methane condenses out, the hydrogen bubbles to the top and provides pressurization, and they save the weight of an insulated pipe to the top of the fuel tank.

Hydrogen at 100 Kelvin is half the weight of methane at 400 Kelvin.  That alone saves 120+ kg in a F9-equivalent first stage fuel ullage space near burnout, something like 0.5% of empty weight.

Saturate with hydrogen? Maybe. Hot propellant backfeed into the tank? I'm dubious. I think the autogenous pressurization will be done a different way. Injecting hot combustion product gases seems dangerous.

ISTM that many payloads will be well within the capabilities of FH.

It's possible they may spend the extra for pure methane on payloads with little margin, but slap cheaper fuel in there for payloads that are just a little beyond F9.

Sounds like the sort of cost optimisation they might move to once recovery and reuse have become routine.

Cheers, Martin

An interesting trade space there. Is the cost of having multiple fuel streams offset by the cost savings of using the cheaper fuel some of the time...

I'm pre-predicting not. We'll see one (high purity) fuel stream here, and another (lower purity at first but improving as industrial base grows) on Mars. But interesting to ponder.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 04/23/2016 01:18 pm
A little self control. Back to closer to the present. What is the future for FH in the next 2-3 years?

A Raptor based US would be about 4 years out (2020) but a M1DVac dual engine 5.2m US could be done in as little as 2 years from now (2018).

For the FH the US is still vastly undersized even with its thrust increase and prop growth/tank stretch of 20%.  That is why there is so much delta V on the center core. A much heavier 200mt+ vs 120mt US would decrease the center core delta V and increase the RTLS payload up over 40mt.

The reason I am so interested in getting the FH RTLS payload above 40mt is that using this vehicle at its reuse price of around $50M brings the launch cost per "CommX" sat [180kg sat launch at 128 at a time] to less than $500K per sat matching their manufacture cost. Such an improved FH used in its easiest to recover stages configuration so that a single set of FH 1st stages used 20 times in 1 year is feasible. "CommX"'s launch rate even at 128 sats at a time will require >10 FH launches per year.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/23/2016 02:27 pm
So if they can make a 5.2m US with two M1DVac engines, they could have a 40 ton payload, what would it be all expendable to LEO, and maybe the ASDS landing, just as an exercise to think about a moon infrastructure with larger payloads. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/23/2016 02:38 pm
A little self control. Back to closer to the present. What is the future for FH in the next 2-3 years?

A Raptor based US would be about 4 years out (2020) but a M1DVac dual engine 5.2m US could be done in as little as 2 years from now (2018).
...
Two points: you're making the implicit assumption they haven't already started on the Raptor upper stage, that they're starting flat-footed right now. If they plan to build a Raptor upper stage, then they probably have already started. The stage could be ready by 2018, by the time Raptor is finished with development. Second, I cannot imagine SpaceX investing so much in a new upper stage unless it is reusable, and likely Raptor-based. Dual-Merlin upper stage would reduce Isp, too. I also distrust the notion that Merlin 1DVac is under-thrust for a Falcon Heavy upper stage. It's already higher thrust than any upper stage I'm familiar with.

Additionally, there is no hint anywhere of a dual-Merlin upper, but the Air Force contract explicitly states that Raptor is for a Falcon 9 and Falcon Heavy upper stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 04/23/2016 02:55 pm
A little self control. Back to closer to the present. What is the future for FH in the next 2-3 years?

A Raptor based US would be about 4 years out (2020) but a M1DVac dual engine 5.2m US could be done in as little as 2 years from now (2018).
...
Two points: you're making the implicit assumption they haven't already started on the Raptor upper stage, that they're starting flat-footed right now. If they plan to build a Raptor upper stage, then they probably have already started. The stage could be ready by 2018, by the time Raptor is finished with development. Second, I cannot imagine SpaceX investing so much in a new upper stage unless it is reusable, and likely Raptor-based. Dual-Merlin upper stage would reduce Isp, too. I also distrust the notion that Merlin 1DVac is under-thrust for a Falcon Heavy upper stage. It's already higher thrust than any upper stage I'm familiar with.

Additionally, there is no hint anywhere of a dual-Merlin upper, but the Air Force contract explicitly states that Raptor is for a Falcon 9 and Falcon Heavy upper stage.
Yes the problem is that we have little insight into which way SpaceX will go in the next 3 years. The only indications is the Raptor contract and the BFR/MCT statements. So yes I think if they make a larger stage it would likely be a Raptor stage. But that also requires pad mods. And there has been no hint of any pad mod work (more visible than stage design work) starting. A MIDVac 5.2m stage would require little if any pad mods. The basic item is that regardless of engine when you double the prop amount in the US on FH you also nearly double the payload amount. A MIDVac 5.2m (230mt prop) stage could achieve a max full expendable of 90mt to LEO. FH has a lot of room for payload growth.

added: A BTW a supper US with 280mt prop and 10mt dry weight (this is the max to make the T/W at liftoff for the FH the same as the F9) could have as full expendable as much as 110mt LEO payload just using an M1DVac. A 3 RTLS would be 50mt and a 2 ASDS center Exp at 91. A 3 ASDS would be 70mt.  A similar Raptor stage of same total max weight of 400mt (prop+stage +payload) would yeild: 58mt for 3 RTLS and 123mt for full Expendable. The FH is a large rocket.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 04/23/2016 03:38 pm
When you put it that way, I wonder what the USAF has in mind to launch on such a beast? That kind of launch capability at those price points would be more disruptive than even F9 has been thus far.

However, a slight reality check may be in order for the next few years at least. They've invested quite a bit as of late in their landing and launch infrastructure. And they still need to get 39A finished for FH and Crew Dragon as well as Vandenberg. I don't see them doing any additional changes, whether 5.2m tooling, methane holding tanks and updating TEs (yet again) for a Raptor US F9 or FH for at least 3 to 4 years. imo. Right now they need to launch, launch, launch...return, return,return...

Edit: I'd say 2020  is a good time frame. SLS is in between flights getting the EUS and Orion finished, Ariane 6 and Vulcan are just starting flight testing and F9/FH re-use operations would be fully operational. So from a  purely competitive standpoint, introducing such a tremendous capability at that point, especially if they could figure out a re-use strategy for certain profiles of a Raptor US or even if they don't bother, they'd be untouchable in the market, both commercial and Govt. imo.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 04/23/2016 04:40 pm
Unfortunately my numbers are max possible and reality will be lower. But the indication is that the FH has a tremendous room for payload capability increase almost entirely through more prop on the US.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 04/23/2016 05:08 pm
I feel raptor is closer rather than later. We keep pushing it to the right because we don't hear much news about it - have people considered that this lack of news is deliberate?


For one thing raptor is a (potential) competitor to BE4, although it does contain a number of critical differences. For another, raptor upper stage is a competitor to ACES. Thirdly, raptor is an enabler for a significantly more capable SLS rival/successor, and all the interests SLS represents. The reason they aren't pontificating about raptor is probably highly similar to the reasons why they aren't pontificating about the satellite network - yet we have hard evidence that they're advancing their team in that direction and plan to launch test sats sometime in the very immediate future.

SpaceX only publically pushes the areas they want everyone to focus on, I.E: the areas where they are already in the lead. This is no bad thing - it's good politics, good business practice and good common sense.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Blackjax on 04/23/2016 05:29 pm
So I have redone the table and made a graphic of it so that it can retain formatting.  Scenarios with all the cores returned have no shading, centre core expendables are yellow, all core expendables are red.

Does anyone have a source for something similar to this for the F9 that shows payloads to different orbits for the RTLS, ASDS, and expendable configurations?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GORDAP on 04/23/2016 08:12 pm
Just wondering, are there any things we might look for on the pad 39A rework in the coming months that would definatively indicate that SpaceX was indeed planning ahead for a 5.2m Raptor US?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 04/23/2016 09:33 pm
Just wondering, are there any things we might look for on the pad 39A rework in the coming months that would definatively indicate that SpaceX was indeed planning ahead for a 5.2m Raptor US?
A separate tank farm from the other two.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 04/23/2016 10:51 pm
Just wondering, are there any things we might look for on the pad 39A rework in the coming months that would definatively indicate that SpaceX was indeed planning ahead for a 5.2m Raptor US?
A separate tank farm from the other two.

Yes but it is probably to early for that. Question for me is, is there space between the core and the TE to allow for a stage to go there? Everything else can be added without major modifications that would affect launches.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: groundbound on 04/23/2016 10:59 pm
Dumb question about this: is manufacturing and/or transportation infrastructure something that might show up early? We know why SpaceX has resisted going to larger diameters so far, are there signs we should look for that this is about to change?

Silly example - new rocket factories adjacent to waterways don't go up overnight.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 04/23/2016 11:17 pm
Yes but it is probably to early for that. Question for me is, is there space between the core and the TE to allow for a stage to go there? Everything else can be added without major modifications that would affect launches.

I would imagine that they would build a new transporter/erector for stages that have Raptor/methane upper stages since there would need to be different fuel lines and connections for methane upper stages versus the current RP-1 upper stages.  At that time they could also have a new design that accommodates a larger diameter upper stage (assuming they create a larger diameter upper stage).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 04/23/2016 11:42 pm
I guarantee you my fellow NSFers that the only thing you will see for the next couple of years going on at their pads is the Falcon as currently configured launching everything it can get its claws on. Cargo Dragon, Crew Dragon including every Gov't and Commercial payload they possibly can. They need stability of configurations, of production, of launch infrastructure right now. Mark this post. If they start to whip out pad mods for a Raptor US before 2019, I'll for 6 months, include a "I was wrong about Raptor US!!!" at the bottom of every post I make thereafter.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 04/24/2016 12:46 am
Silly example - new rocket factories adjacent to waterways don't go up overnight.

Actually, the pad 39a HIF did go up surprisingly fast...



If they start to whip out pad mods for a Raptor US before 2019, I'll for 6 months, include a "I was wrong about Raptor US!!!" at the bottom of every post I make thereafter.

2019 might be a little too far.  But I'll agree in the shorter term: the mandate to the troops is clearly to minimize infrastructure changes until they get the launch cadence up.

On the other hand, it seems that one reason they've done so much of the infra work recently is that their plans were being delayed on other fronts.  If some of these missions had launched earlier, they would have been on v1.1s. But they got delayed so the v1.2 migration caught up to them.

So this refocus might just mean, "we're putting the development team on long term projects (MCT? Raptor?), so you've got a window before we start making infrastructure changes again.  Use that time to get the launch cadence up!". This swaps cause and effect from the conventional reading in the first paragraph.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 04/24/2016 12:56 am
Yes but it is probably to early for that. Question for me is, is there space between the core and the TE to allow for a stage to go there? Everything else can be added without major modifications that would affect launches.

I would imagine that they would build a new transporter/erector for stages that have Raptor/methane upper stages since there would need to be different fuel lines and connections for methane upper stages versus the current RP-1 upper stages.  At that time they could also have a new design that accommodates a larger diameter upper stage (assuming they create a larger diameter upper stage).

You may well be right. But I can imagine that the existing TE can be modified and remain backward compatible as they will IMO fly both versions in parallel for quite a while to maintain launch cadence.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: robert_d on 04/24/2016 01:56 am
When they static fire the Falcon Heavy - will they do all three cores simultaneously or will they do them sequentially? Assuming a thorough test program at McGregor, what would be learned by a concurrent static fire that would not be learned by firing each individually?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Wolfram66 on 04/24/2016 02:14 am
It wouldn't really be a test of the heavy if you fire them sequentially. Test like you fly, fly like you test is the mantra
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: weepingdragon on 04/24/2016 02:16 am
Loooonnngggg time lurker!! I've read through most the spacex topics over the years and have spent some time searching through google/nsf and coming up empty.

Has anyone (I'm sure someone, somwhere has, i just lack sufficient google-foo/patience) done a decent ballpark estimate of the structural capability of the falcon 9 first stage??

i.e. what theoretical mass could the existing structure support to an orbital staging point.

Is there any point (besides the usual fun of stretching the mind) of working out a 5+ meter second stage if the first stage can't support the mass??  My own believe (not enough facts for an opinion) is 20-30% more than current second stage + payload is possible, but more?

If anyone can point me the right direction would appreciate it, thanks. 

ps, no L2 access, no $$, but put L2 links up if they exist for those who do and would be interested  ;D



Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: IainMcClatchie on 04/24/2016 02:42 am
In flight, they just inject a little hot propellant back into the tank for pressurization.  The methane condenses out, the hydrogen bubbles to the top and provides pressurization, and they save the weight of an insulated pipe to the top of the fuel tank.

Saturate with hydrogen? Maybe. Hot propellant backfeed into the tank? I'm dubious. I think the autogenous pressurization will be done a different way. Injecting hot combustion product gases seems dangerous.

I should have said hot fuel rather than hot propellant (as in burned gases).  The hot fuel coming off the engine cooling jacket could be tapped for a hot feed back to the fuel tank.  I think the Shuttle did that, I'm just suggesting that rather than feeding the hot gas directly into ullage, you can bubble it through the subcooled fuel in order to (a) get a little more ISP, (b) reduce the weight of the ullage gas, and (c) lose the weight of that insulated pipe.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 04/24/2016 03:47 am
I guarantee you my fellow NSFers that the only thing you will see for the next couple of years going on at their pads is the Falcon as currently configured launching everything it can get its claws on...

I agree, specifically because between Falcon 9 and Falcon Heavy, as currently configured, they can take care of the vast majority of payloads they need to stay busy.  SpaceX would only make a upper stage change to capture new business that, for whatever reason, Falcon 9 and Falcon Heavy can't satisfy at their current prices and capabilities today - and I'm not sure such a significant customer demand for such exists.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 04/24/2016 04:01 am
SoaceX  could be that customer. Using an F9-Raptor vehicle would be just the ticket for pre-BFR Mars precursor missions.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GORDAP on 04/24/2016 12:59 pm
I guarantee you my fellow NSFers that the only thing you will see for the next couple of years going on at their pads is the Falcon as currently configured launching everything it can get its claws on...

I agree, specifically because between Falcon 9 and Falcon Heavy, as currently configured, they can take care of the vast majority of payloads they need to stay busy.  SpaceX would only make a upper stage change to capture new business that, for whatever reason, Falcon 9 and Falcon Heavy can't satisfy at their current prices and capabilities today - and I'm not sure such a significant customer demand for such exists.

Could it not be possible though that a business case could be made for a reusable US even if it captured no new business, compared to the current US?  That is, even if it had no increase in payload to orbit (or if it did, it was essentially wasted, as few customers need this capacity). 

I'm just thinking that 12-18 months down the road the F9 and FH development will be potted, the 1st stage(s) and even fairing reuse will be routine, work on the Crew Dragon and launch infrastructure will be tapering off, etc.  So what better will there be left to do for the bulk of the standing SpaceX army?  I'd suspect that the business case would't close for the savings of a reusable US if the engine development were considered.  But given that the Raptor is being developed anyway, I'd think the remaining expense of building a reusable US around it would make economic sense, even if it didn't expand the number of SpaceX launches.

And I also think that Musk's dream and mantra about rapid and complete reusability is going to haunt him until he finally gets his reusable upper stage.  So I'm betting we'll see a clear move to develop this stage, starting in the next 12-18 months.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/24/2016 01:18 pm
weepingdragon, they have already said they could launch 53 tons into LEO with Falcon Heavy based on the 1.1 configuration.  The Falcon 9 vs 1.2 alone can launch about 20 tons to LEO.   Someone has figured on another thread that F9 could do about 28 tons alone with a 5.2 methane upper stage. 

I'm not a rocket scientist, so maybe someone could let us know if the structure of the first stage of FH could handle not only the fuel load but a 90 ton payload that was figured.   I would like to know also.   
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: robert_d on 04/24/2016 01:38 pm
It wouldn't really be a test of the heavy if you fire them sequentially. Test like you fly, fly like you test is the mantra
I'm in general agreement with the sentiment, but can you be more specific? What precisely would be different? Can't be stresses on the stages and transfer of forces because they are held down. That information has to come from McGregor. All engines would be tested and all ground support equipment. I'm just asking whether a hypothetical two minute interval between firings would make a difference? Upside would be if the first one fails or there is a GSE problem (like a stuck valve, say) you don't need to fire the other two (or one) until the issue is resolved. Possibly allowing up to a day in between? The readiness review could be done in stages, relieving the surge in staff needed if all three were done simultaneously.
Just trying to think beyond the hardware costs to consider ways to reduce cost of processing. Another would be to reduce full duration firing at McGregor or even complete stage firing altogether. Other vehicles do not seem to require this.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: robert_d on 04/24/2016 01:48 pm
weepingdragon, they have already said they could launch 53 tons into LEO with Falcon Heavy based on the 1.1 configuration.  The Falcon 9 vs 1.2 alone can launch about 20 tons to LEO.   Someone has figured on another thread that F9 could do about 28 tons alone with a 5.2 methane upper stage. 

I'm not a rocket scientist, so maybe someone could let us know if the structure of the first stage of FH could handle not only the fuel load but a 90 ton payload that was figured.   I would like to know also.
Per astronautixs.com there is almost 2 feet in between the falcon heavy core and each booster. Maybe an external support frame could be placed in that position to help support the payload. Or maybe even long thin pressurized tanks that would hopefully provide the propellants to compensate for their own weight.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: matthewkantar on 04/24/2016 03:55 pm
In this photo from McGregor, though the flame trench seems wide enough for an all up test of the Heavy, it does not look to me like the hold-down area can be easily swapped out for a three core job. It does not look as simply modular as the TEL at Vandenberg for instance. Is it possible that they decided to do the all up static fires at the new-to-SpaceX pad in Florida?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gospacex on 04/24/2016 05:49 pm
Adding more prop for the center 1st stage is counter reuse. Make the US bigger.

These two options aren't exclusive :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: CuddlyRocket on 04/24/2016 08:21 pm
I don't think the Raptor will burn 100% methane.  I know liquid propane will dissolve an interesting amount of hydrogen.  I'm pretty sure liquid methane will too.  The bump in ISP is easy to get without a big change in vapor pressure at a given temperature, so they'll take it.

How would this work with the use of the Raptor on Mars? Perhaps the Raptor is designed to work with either methane or hydrogen-infused methane; there are slightly different Raptors on the BFR and BFS; or it is envisaged that hydrogen-infused methane can be produced on Mars? The last would require a source of hydrogen on Mars, because otherwise the effective additional propellant that the carbon in methane supplies outweighs the greater ISP of hydrogen.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: eriblo on 04/24/2016 09:35 pm
I don't think the Raptor will burn 100% methane.  I know liquid propane will dissolve an interesting amount of hydrogen.  I'm pretty sure liquid methane will too.  The bump in ISP is easy to get without a big change in vapor pressure at a given temperature, so they'll take it.

How would this work with the use of the Raptor on Mars? Perhaps the Raptor is designed to work with either methane or hydrogen-infused methane; there are slightly different Raptors on the BFR and BFS; or it is envisaged that hydrogen-infused methane can be produced on Mars? The last would require a source of hydrogen on Mars, because otherwise the effective additional propellant that the carbon in methane supplies outweighs the greater ISP of hydrogen.

This has been discussed previously, but to save you and me from searching: the solubility of hydrogen in subcooled methane is on the order of 5e-4 mole fraction (http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19680020605.pdf) which is an entirely uninteresting amount :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 04/24/2016 11:32 pm
I guarantee you my fellow NSFers that the only thing you will see for the next couple of years going on at their pads is the Falcon as currently configured launching everything it can get its claws on...

I agree, specifically because between Falcon 9 and Falcon Heavy, as currently configured, they can take care of the vast majority of payloads they need to stay busy.  SpaceX would only make a upper stage change to capture new business that, for whatever reason, Falcon 9 and Falcon Heavy can't satisfy at their current prices and capabilities today - and I'm not sure such a significant customer demand for such exists.

Upgrades to the Falcon upper stage that could have business justification:

1) Extended life for GEO insertion
2) Reuse

What developing a methalox Falcon upper stage could do to accelerate SpaceX's goal to enable the colonization of Mars:

1) Developing the following technologies to enable the two business cases above
   a) Raptor vac engine
   b) Reentry for a propulsive orbital stage including from interplanetary velocities (tested on GEO insertion)
   c) Methalox RCS from microgravity fuel tank without ulage acceleration
   d) Long life power (methalox fuel cell, diesel generator, or solar)
   e) low to zero boil off methalox in LEO/GEO solar heating environment

2) The upper stage developed for the above case could also easily be used as a platform for the following enabling tasks and development technologies:
   a) Directly accelerating 15t to TMI while allowing side core RTLS and centre core ASDS
   b) In space propellant transfer testing
   c) Depot development

So thinking about 1.a) above the current cost to do this for the heaviest comms satellites or DoD payloads is somewhere between $100 and $200M more than for GTO.  So, as a result there is no market for it except for DoD, which might be 1 payload a year, however if there were an option to do this for an additional $50M over an F9 GTO launch (or the price of a competitors GTO launch) there might be some commercial demand.

1.b) is a very different matter. For this to be a legitimate business reason then the cost to use the stage in the 1.a case has to come down to less than the existing upper stage. So in fact a GEO launch would have to cost less than a 2 core RTLS one core ASDS GTO launch with an expendable upper stage. Currently, from the data I have seen here on NSF, my best guess is that the existing Falcon upper stage costs $11M, if there were a reusable Raptor based upper stage that notionally cost $25M to manufacture, then even at 5 reuses, it would be worth it. However while it offers potential costs more than twice as much today, it doesn't really drop the entry price for comms satellites or other space based applications, but it drops the cost to set up really big things to just about the current entry price.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: IainMcClatchie on 04/25/2016 08:52 am
This has been discussed previously, but to save you and me from searching: the solubility of hydrogen in subcooled methane is on the order of 5e-4 mole fraction (http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19680020605.pdf) which is an entirely uninteresting amount :)

Egad.  They tested the solubility of oxygen in liquid methane.  Hopefully nobody was in the room when they tried that.  [Reads further.]  Oh boy.
Quote
Fluorine cannot be considered [as a pressurant gas] because it is far too reactive.

Good to read there were some things they wouldn't try.  Still, I do note
Quote
The experiment was continued by gently swirling the LNG by hand.

I'm trying to imagine hand swirling 1.27 liters of LNG + O2, having noted that the LOX forms an "ideal mixture" with the LNG when it subcools to its boiling point.  Heart palpitations and sweaty palms.  I am not cut out for this sort of work.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: testguy on 04/25/2016 02:48 pm
OK we are a little more than six months from the demo flight.  I don't believe the payload has been revealed yet.  I simply can not believe that the demo flight would just carry a mass simulator.  It is too much of an investment and opportunity for just throwing some mass.

A year or two ago there were rumors as to a BEO mission for the demo flight. I would have hoped that details of the first flight would have been shared by SpaceX when revealing the updated performance numbers for the FH which is now over due.

Does anyone know when the payload will be announced and know what it is?  If not, anyone care to speculate as to the payload and mission?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 04/25/2016 03:03 pm
OK we are a little more than six months from the demo flight.  I don't believe the payload has been revealed yet.  I simply can not believe that the demo flight would just carry a mass simulator.  It is too much of an investment and opportunity for just throwing some mass.

A year or two ago there were rumors as to a BEO mission for the demo flight. I would have hoped that details of the first flight would have been shared by SpaceX when revealing the updated performance numbers for the FH which is now over due.

Does anyone know when the payload will be announced and know what it is?  If not, anyone care to speculate as to the payload and mission?

I was thinking about this over the weekend.  Maybe they'll find a customer, but I wouldn't be surprised if they don't. 

The sales price of a FH demo mission will have to be less than the cost of flying on a used F9.

Further it's hard to imagine Comsat operators risking a large expensive bird with large revenue generating potential on the first FH. 

If they fly a demo mission it seems reasonable that they'll want to return all 3 cores to RTLS.  If that's successful they'll essentially have a FH ready for another mission in a few months. 

Also, it seems reasonable it won't be a Dragon, they need to fly the payload fairing and demonstrate that function on the FH.

I think it's best for SpaceX to fly the FH as soon as it's ready and build confidence. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RonM on 04/25/2016 03:44 pm
It might be a Dragon. The US and fairing are the same as on F9. There's not really a need to test those items; it's the core and booster concept that they need to demonstrate. A used Dragon would make a good reusable 'mass simulator' if they don't have a payload.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: testguy on 04/25/2016 03:51 pm
It is almost the middle of 2016.  With Spacex's Mars plan having an initial manned mission by 2025, wouldn't we believe that they will have to begin investing in company funded missions in the near future?  That is why I am hoping for at least lunar mission on the demo flight on FH.  Need to gain BEO experience.  Maybe a road map to get to a manned Mars mission would warrant a separate thread prior to Elon's paper in September..   

I agree a customer funded payload to the demo flight is unlikely.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mike_1179 on 04/25/2016 03:52 pm
It might be a Dragon. The US and fairing are the same as on F9. There's not really a need to test those items; it's the core and booster concept that they need to demonstrate. A used Dragon would make a good reusable 'mass simulator' if they don't have a payload.

Are there spare (complete) Dragons lying around to be used? It's been posted here that components from one Dragon are sometime re-used on subsequent Dragons. While the pressure vessels are new, some of the stuff inside that makes it a Dragon might be better used as CRS flight hardware.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 04/25/2016 04:46 pm
SpaceX has a lot going on with F9 reuse, FH, Dragon 2, FH, Fairing re-use and Raptor.  Why add to an already complicated mission.

Rational behind flying with a fairing is that customers will want to see it work and that SpaceX will proceed with plans for a dummy payload with a fairing.  If they have a paying customer close to launch, having a fairing ready enables an timely change from a dummy to live payload.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Baranquilla on 04/25/2016 05:04 pm
Has anyone ever noted the capabilities on the SpaceX website for the falcon heavy? It says 6.4 Mt at the price but 21200 kg at the performance column (while it says the same in both columns for falcon 9).

I am wondering if this is the payload penalty that comes with 3 core recovery. Could this just be a mistake, or a relic from the expendable time period? At one time they had a price of 135 M $ for a Falcon Heavy on that page.

Edit: Feel free to remove if already discussed
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Billium on 04/25/2016 05:12 pm
I agree that Spacex already has a lot on their plate and they likely don't have any time to do something fancy with the 1st Falcon Heavy launch, getting all 3 cores back would advance their next flights and help them make some money.

However the political timing is good for something amazing. Commercial Crew will almost be completed and it will be too late for congress to pull funding even if they get upset about a possible competitor to SLS/Orion. Also, Elon will be giving his speech on Mars plans in September. Imagine if he can add in "and in November we're going to launch a Dragon around the moon to test the heat shield for Mars return velocity."

Wasting an opportunity to test something does not seem like Spacex stile, and they've had years to think about and plan for it. Besting SLS/Orion to the same mission by 2 years would be a statement.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 04/25/2016 06:32 pm
I share the passion but sometimes reality is just a bit more boring and straight-forward. FH needs to do one thing and one thing only. Have a successful test flight where it places an appropriate (Faring enshrouded) payload, dummy or otherwise into the appropriate orbit. (as well as boosters/core return)

FH already has paying customers waiting for it, both Commercial and Government. A successful FH flight in and of itself will make all the "statement" they need to make and ensure they can begin to tap additional revenue streams. Without which they can not finance their other more imaginative visions.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 04/25/2016 07:10 pm
Passion aside, we'll only see traction here when they can keep the tempo of F9 launch ops up. If you have erratic scheduling of one booster, three has got to be a lot harder to corral.

And there's been no tests, no fit checks, we've yet to see a hotfire on 39A. Not to mention all the in between "tweaks" following landing success/failures.

The reason you don't see FH is likely that too much in the way of sideshows are distracting from what you need to bring that off. Especially you want it to become boringly regular on F9 launches before you try that trick next.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Fan Boi on 04/25/2016 07:23 pm
I can't help but wonder if Bigalow might be willing to risk volunteering a "boiler plate" load for the initial Heavy flight. He risks losing hardware but might get his first module up for cheap, or maybe free.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dror on 04/25/2016 08:21 pm
Has anyone ever noted the capabilities on the SpaceX website for the falcon heavy? It says 6.4 Mt at the price but 21200 kg at the performance column (while it says the same in both columns for falcon 9).

I am wondering if this is the payload penalty that comes with 3 core recovery. Could this just be a mistake, or a relic from the expendable time period? At one time they had a price of 135 M $ for a Falcon Heavy on that page.

Edit: Feel free to remove if already discussed

It was discussed a few pages ago
http://forum.nasaspaceflight.com/index.php?topic=39181.msg1512368#msg1512368

Many thought that relates to reusable vs expendable.
I think it hints on double payloads launchs
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dror on 04/25/2016 08:23 pm
I can't help but wonder if Bigalow might be willing to risk volunteering a "boiler plate" load for the initial Heavy flight. He risks losing hardware but might get his first module up for cheap, or maybe free.
Didn't he just say that falcon's fairing isn't big enough?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 04/25/2016 08:25 pm
Passion aside, we'll only see traction here when they can keep the tempo of F9 launch ops up. If you have erratic scheduling of one booster, three has got to be a lot harder to corral.

And there's been no tests, no fit checks, we've yet to see a hotfire on 39A. Not to mention all the in between "tweaks" following landing success/failures.

The reason you don't see FH is likely that too much in the way of sideshows are distracting from what you need to bring that off. Especially you want it to become boringly regular on F9 launches before you try that trick next.

Bingo, I think people discount FH as just being 3 F9's.  It's a different vehicle with all the development and headaches that brings. 

Makes perfect sense that the F9 needs to become routine to free up the development resources for FH.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/25/2016 08:34 pm
I guarantee you my fellow NSFers that the only thing you will see for the next couple of years going on at their pads is the Falcon as currently configured launching everything it can get its claws on...

I agree, specifically because between Falcon 9 and Falcon Heavy, as currently configured, they can take care of the vast majority of payloads they need to stay busy.  SpaceX would only make a upper stage change to capture new business that, for whatever reason, Falcon 9 and Falcon Heavy can't satisfy at their current prices and capabilities today - and I'm not sure such a significant customer demand for such exists.
The key is that they could now serve all existing customers with FULLY reusable Falcon 9 and Falcon Heavy. A Raptor stage would almost certainly be designed to be reusable (something which is harder than first stage reuse and will likely require several tries before they succeed, just like with first stage recovery... and better try and fail at recovery at the Falcon 9 upper stage scale than at the BFS scale! And better get started on it right away, otherwise they won't have enough "lessons learned" to effectively design BFS).

SpaceX always does improvement even when others say they should just focus on flying out their manifest. Outsiders have been saying that since Falcon 1!!! I do expect most Falcon 9/Heavy flights to be fairly unchanged in the next couple years, but I most certainly do NOT expect that to be the only thing they try, even at the launch pad...

By the way, what do I get when your guarantee fails?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/25/2016 08:43 pm
SpaceX's schedule is not getting any less aggressive. In addition to solving all of Falcon Heavy's hiccups, they have to finish Raptor and start sending robotic equipment to Mars as well as proving all the big technologies needed for MCT. They can't merely spend the next 2 years flying out their current manifest.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 04/26/2016 09:03 pm
Considering what the sizes of the development groups are for certain parts (engines, and software to name the most significant ones) that these groups would need something to work on. Although there is always work on software, there is not so much re-work/fix work on the engine designs. So the engine design groups are heavily into Raptor work and shifting more and more to that being their main work. But that leaves the tank design guys seemingly in limbo at the moment with nothing other than advance designs of the BFR and MCT. So the guesses at what is being worked on at what levels is very speculative.

In general SpaceX has surprised us with engineering directions and accomplishments that we never saw coming: super cooled prop ( only after identifying the equipment being installed at VAFB), M1DFT (we thought that the M1D was already at its max thrust), landing on a barge (when we saw them building an ASDS) and other smaller items. Our guesses as to what they are up to has been sort of short sighted until evidence of what they were really up to hit us in the face.

The question is, is this contract for work on a Raptor for use on an US one of those pieces of evidence that is about to hit us in the face?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 04/26/2016 09:31 pm
SpaceX's schedule is not getting any less aggressive. In addition to solving all of Falcon Heavy's hiccups, they have to finish Raptor and start sending robotic equipment to Mars as well as proving all the big technologies needed for MCT. They can't merely spend the next 2 years flying out their current manifest.

They can't "merely" but they do need to up the launch rate so some subset of the company needs to be working on just that. Promising to increase the rate only works for a while, after a while you have to actually increase it... (and they ARE on an improvement curve but that's a big manifest to fly out.)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 04/26/2016 10:37 pm
SpaceX's schedule is not getting any less aggressive. In addition to solving all of Falcon Heavy's hiccups, they have to finish Raptor and start sending robotic equipment to Mars as well as proving all the big technologies needed for MCT. They can't merely spend the next 2 years flying out their current manifest.

They can't "merely" but they do need to up the launch rate so some subset of the company needs to be working on just that. Promising to increase the rate only works for a while, after a while you have to actually increase it... (and they ARE on an improvement curve but that's a big manifest to fly out.)

Further, they need to increase revenue by delivering the manifest to orbit. 

Regarding the Mars fantasies, those aren't even getting off center until there is a big juicy flow of profits.  They can't stay being a startup burning money forever.

Edit: The big comsats that FH launch will book big revenue and profits and help make future development possible.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/26/2016 10:41 pm
SpaceX would only make a upper stage change to capture new business that, for whatever reason, Falcon 9 and Falcon Heavy can't satisfy at their current prices and capabilities today - and I'm not sure such a significant customer demand for such exists.

Ron, your business background influences the way you think about this. Were we talking about ULA, I would completely agree, but we are talking about a genius prodigy billionaire who desperately wants to go down in the history books as the guy who made humans an interplanetary species. He doesn't fit the average business mold. In fact, he doesn't fit any mold of any kind.

We know they are working on this Raptor US, because they have a contract with the USAF to develop the engine specifically for use on such a stage. You seem to be simply ignoring that fact. Musk does not do things in traditional ways, other than being very smart about incremental progress. He seems to have a knack for making money off of everything he touches, even when the initial idea seems counter-intuitive.

His goal is to get us to Mars. I think he is playing a cagey  game right now, trying not to seem in competition with NASA, but I am feeling more and more convinced that one day the political pressure will become more than the old space senate cadre can withstand, SLS/Orion will be cancelled, and NASA will become the paying customer for Musk's Mars architecture.

At the present point in time, the USAF has provided a way for Musk to get supplemental government funding for his Mars engine, and he's smart enough to start working on it sooner rather than later by making it a part of Falcon now, so that it's ready to be part of MCT a few more years down the road.

Had the guy decided to devote his life to chess, I imagine he would be the world champion. He sees many moves into the future and he knows how to take advantage of any and every situation that presents itself to him.

It is a mistake to judge this man through the lens of a traditional paradigm. He is far more complex than the average businessman.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/26/2016 10:53 pm
Further, they need to increase revenue by delivering the manifest to orbit. 

Regarding the Mars fantasies, those aren't even getting off center until there is a big juicy flow of profits.  They can't stay being a startup burning money forever.

The FH will book big revenue and profits and help make this possible.

I agree that a robust manifest flow will provide the funding to keep them in the black. At the same time, Musk has proven himself quite capable of multitasking. I imagine the bulk of cash flow will come from F-9, and this venture into reusability may make that far more profitable than anyone dared dream. It is that, not FH, that will pump the money.

As for Mars fantasies, just keep in mind that less than 69 years passed between the first powered flight at Kitty Hawk and Neil Armstrong taking that one small step onto Lunar regolith. It's not a fantasy to smart people, unencumbered by government bureaucracy, who commit themselves to really hard work. The American spirit of innovation is alive and well in this immigrant.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 04/26/2016 11:36 pm
I'll just caution about falling into the cult of personality.  Yes, Elon is the driving force---but he's smart enough to surround himself with other brilliant folk who share his goals.  Gwynne in particular seems to be the lead player on the business side and should get credit for winning contracts and keeping SpaceX in the black.  And the propulsion and guidance folks have obviously had a lot to do with SpaceX's visible successes (landing the first stage).  Elon can make mistakes---over at Tesla the model X was rather "over exuberantly" designed, as he himself has admitted---but with a solid team around him everyone's poor impulses are kept in check.

But I totally agree with oldAtlas_Eguy that all the engineers are going to be kept busy.  This explains some delays, when engineers are otherwise employed, but also explains why SpaceX's development plan does not proceed in a straight line toward a single goal.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/27/2016 12:08 am
I'll just caution about falling into the cult of personality.  Yes, Elon is the driving force---but he's smart enough to surround himself with other brilliant folk who share his goals.

Exactly. That is one more part of his genius, surrounding himself with other brilliant folk who share his goals.

And I think what he achieved with the luxury Teslas set the stage for the economy model.

As for cult of personality, I don't give a hoot about his or anyone's personality. Girls screaming at concerts and rants by Donald Trump are part of a cult of personality. This is about his mind, vision, and leadership. There really is a difference in putting stock in someone due to those things vs. a cult of personality. One is based on nothing more than emotional responses, the other on analytical reasoning.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 04/27/2016 12:20 am
Sure.  I just don't like to see folks writing stuff like:

At the present point in time, the USAF has provided a way for Musk to get supplemental government funding for his Mars engine, and he's smart enough to start working on it sooner rather than later by making it a part of Falcon now, so that it's ready to be part of MCT a few more years down the road.
...when I'm fairly certain the USAF contract is due to Gwynne.  Would Elon chase these contracts without her?  Who knows---but a decent amount of the stuff attributed to "Musk" in Tom's post is not Elon's doing at all.  Write "SpaceX", not "Musk", unless you are sure it is the man himself doing it.

Yes, Elon is indirectly responsible, by hiring smart people and establishing company culture.  But don't anthropomorphize SpaceX and call it Elon.

Pulling the thread back on topic: identifying the company with an individual seems to lead to some of these analyses that presuppose SpaceX has a single plan and a single goal and a single "current project".  In reality there may be multiple projects and dead ends and cross purposes.  Not everything may fit into a single master narrative, and some projects may be pursued speculatively.  The Raptor upper stage may well be one of these.  Sure, it *may* end up as part of the Falcon Heavy development plan.  But it may not.  It may be a dead end.  Not even SpaceX may know for sure yet.

All we know is at least one person is either working on it or otherwise thought it worth putting in the USAF contract proposal.  (And I've been in organizations where the contract reflected biz dev's view of reality, with no engineering support.  Conversely, the contract could be revealing the tip of a much deeper engineering iceberg, as oldAtlas_Eguy suggests.)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 04/27/2016 02:43 am
They can't "merely" but they do need to up the launch rate so some subset of the company needs to be working on just that. Promising to increase the rate only works for a while, after a while you have to actually increase it... (and they ARE on an improvement curve but that's a big manifest to fly out.)
Further, they need to increase revenue by delivering the manifest to orbit. 

That's what I said...

Quote
Regarding the Mars fantasies, those aren't even getting off center until there is a big juicy flow of profits.  They can't stay being a startup burning money forever.

I'm not sure I agree. This has been debated before in other threads (and extended debate should go there, I'm just summarizing) but SpaceX is not like other companies. And the billionaires of today are not like the billionaires of 50 or 100 years ago. There's a cadre of them out to change reality. They've said so and they are writing the checks. Big ones. SpaceX isn't in startup mode. It's in Amazon mode... growing, increasing revenue but not making a profit or much of one, all the funds go to increasing capability and reach and capital assets...

But it has an advantage over Amazon, in Musk, who inspires.... there's a reason he's called the real life Tony Stark, after all.. He inspires his cadre of brilliant associates who design the things, sell the launches, deliver operational excellence, etc. But he *also* inspires those check writing billionaires. There is a good chance (at least 10%) that perfect storm of reality bending he's created will last until the Mars liners are flying regularly. Maybe not, but it's the way I'm betting.

Edit: YMMV and I don't want to argue the point in this thread. Just realise that there are people who don't see things the same as you (which is always good advice, in any context, just about)....
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 04/27/2016 03:33 am
I don't want to offend anyone here, and I don't profess to have any special knowledge on anything I am about to speak about than is publicly available. This is speculation. But Lar (and other recent posts here) touch on something that seems obvious to me: Elon is both different but then again not different from many of us who post here. Look at his mannerisms when speaking, consider his odd tendency to over explaining, his apologetic laugh when he presumes people might not 'get' what he is saying, breaches of normal big business PR etiquette, the very evident frustration sometimes with things like the USAF block buy, his personal relationships, and things like his wing walking.  He is obviously neuroatypical. He has a mensa level IQ, but he doesn't know everything, and knows that he doesn't.  Unlike charismatic people who are well spoken (ex. JFK, Ghandi, U Thant, Golda Meir, Warren Buffet etc) it isn't a personality cult that has sprung up around him, but there is a cult, it is not his fault, though I am positive he is aware of it and uses it when it is convenient, but he is not emotionally able to use it the way the examples I gave can and do. Instead, Elon plods along doing what he thinks will make the outcomes he thinks are best come about. Unlike Bill Gates or Steve Jobs he is not as fantastic at surrounding himself with the sycophants who work with him best, yet he still manages at least as well as them so far to keep his organizations together.  So, what is special and different about Elon?  Actually, not so much except that he has kept it together better than any of the previous space pioneers who managed to get a snowball rolling downhill.

I want to see him succeed. At any point along the way it may fracture and fall apart, but as long as it doesn't he is making progress in a way no one else can. We can draw parallels, make analogies, opine about the fate of humanity, but for me, at the most personal level, I just want to see us become extra planetary as a species. Mars isn't magic to me, but if it is to anyone and they help make humanity extra planetary then they are fellow travellers to be encouraged. Elon, Jeff, Larry, heck Sergei, Steve and Peter, and many more are working to put humanity out there, they have picked up from the philosophies of Tsiolkovsky, Von Braun, Goddard and their early work and said "yes, lets go".  A city on Mars is not a fantasy, any more than putting a man on the Moon was. However the reason to do it is a fantasy, and it is one we should encourage as unscrupulously as colonizing Venus was in "The Space Merchants".  Let's convince people that asteroid mining is as desirable today as California Gold was in 1849, or Dawson Gold in 1902.  The ultimate benefit is a rich culture with great stories about the daring do of mankind (think of what a modern Jack London would write about asteroid miners and Martian colonists) and as well making us space faring civilization that could survive at least an order of magnitude longer than we will if Earth bound.  Western civilization is getting almost as long in the tooth as the water monopoly of Nile Centric Egypt, if we don't move out into space we will surely rot from within. So, to quote Tennyson:

Come, my friends,
’Tis not too late to seek a newer world.
Push off, and sitting well in order smite
The sounding furrows; for my purpose holds
To sail beyond the sunset, and the baths
Of all the western stars, until I die.
It may be that the gulfs will wash us down:
It may be we shall touch the Happy Isles,
And see the great Achilles, whom we knew.
Tho’ much is taken, much abides; and tho’
We are not now that strength which in old days
Moved earth and heaven, that which we are, we are;
One equal temper of heroic hearts,
Made weak by time and fate, but strong in will
To strive, to seek, to find, and not to yield.


It is not Musk forcing us to do this, it is those romantic enough to see that Musk is the practical embodiment of what needs to be done to allow it that would force ourselves to go along.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/27/2016 03:37 am
Also, NASA is intent on getting to Mars and is spending billions of dollars every year supposedly to do this. SpaceX is already getting a sizeable amount of that already for Dragon 1 and 2, plus the occasional robotic mission. And reuse/recovery of an upper stage would solve some really hairy problems with Mars EDL well before NASA can afford to solve them.

SpaceX is positioning itself to utilize NASA as a super-obvious partner and funding source for "Mars fantasies." SpaceX doesn't have to and isn't going to wait until they fly out their manifest to pursue Mars. They will be doing both simultaneously.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dorkmo on 04/27/2016 05:30 am
since we're talking about elon in the heavy thread...
when elon was asked about FH at the last nasa post launch breifing his first reaction to the question seemed to indicate the final stretch to FH maiden flight has been a head ache for the company.
i also think its interesting to note that we havent seen any FH hold downs and mounts in all the places we would expect to see them. test stand/TELs
makes me wonder if its going to be pushed back to 2018? could they be making enough progress on methane engines that they might be considering waiting for a methane falcon for the heavy? if they have to redesign the octoweb for F1.2 perhaps there will be a different mounting layout, which might explain the delay of a heavy mount?

kinda reminds me of the new mexico test infrastucture that got leap frogged by the recovery campaign. perhaps they are looking a year or two down the line and realize things are going to be changing and instead of doing double work to make it work now, just focus on the upcoming design.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/27/2016 05:46 am
Falcon Heavy has been built; finishing touches are being put on. Wait a couple months, you'll see tests.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: WBY1984 on 04/27/2016 05:57 am
I don't think FH will be bypassed, Dorkmo, it seems too close to fruition for that. However I too noted that heavy sigh he let out when he started talking about FH. He didn't sound at all confident about it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dorkmo on 04/27/2016 06:04 am
that was my hail mary of a post to get into the "I Showed SpaceX The Way To Do It!" thread ;) gota play to win! lol

cant wait to see that huge mammer jammer lift off. F27!

maybe we'll see something like an octoweb 1.1?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 04/27/2016 08:35 am
I don't think FH will be bypassed, Dorkmo, it seems too close to fruition for that. However I too noted that heavy sigh he let out when he started talking about FH. He didn't sound at all confident about it.

FH was the best solution to give SpaceX heavy lift in 2011. It's no longer the most efficient one if they believe they have the capability to skip straight to a raptor architecture - I don't think they do, but Elon knows better than me  :). However, FH will still do them a lot of good once they get the LV in the air - for at least a year they'll have greater heavy lift capacity than anyone else (another first for the tick sheet) and it appears to make economic sense as an LV.

FH will happen - but I view it as a stop gap. There will be a point where BFR can fill in the roles of most LVs.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 04/27/2016 01:15 pm
I don't think FH will be bypassed, Dorkmo, it seems too close to fruition for that. However I too noted that heavy sigh he let out when he started talking about FH. He didn't sound at all confident about it.

Standard lowering of expectations... it is a new configuration after all and stuff happens.
I doubt that he is not confident it can be made to work.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 04/27/2016 01:28 pm
A Falcon 9 v1.2 with a metholox Raptor upper stage expendable can get about 28 tons to orbit, and about 20 tons for RTLS.  This may make the lower throw weight heavies obsolete.  Even sending an 8 ton payload to LEO, with say an 8-10 ton SEP propulsion system attached, that can get the 8 ton payload to GSO, there would be no need for Falcon heavy except for deep space payloads. 

Depends on what they throw their money into.   
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 04/27/2016 01:47 pm
A Falcon 9 v1.2 with a metholox Raptor upper stage expendable can get about 28 tons to orbit, and about 20 tons for RTLS.  This may make the lower throw weight heavies obsolete.  Even sending an 8 ton payload to LEO, with say an 8-10 ton SEP propulsion system attached, that can get the 8 ton payload to GSO, there would be no need for Falcon heavy except for deep space payloads. 

Depends on what they throw their money into.

FH is being developed to serve the heavy GSO market and Delta IV Heavy USG market -- which accounts for sufficient market to pay for development.  In this role, it can completely eliminate the need for F9 expendibles.

The other purpose goes beyond existing commercial/government markets.  A high energy upper stage, especially if it becomes reusable, begins the beyond LEO campaign, while making commodity launches like com sat constellations and propellants more economically viable.

FH with or without a Raptor upper stage seems too big only from the perspective of what has been.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 04/27/2016 01:50 pm
A Falcon 9 v1.2 with a metholox Raptor upper stage expendable can get about 28 tons to orbit, and about 20 tons for RTLS.  This may make the lower throw weight heavies obsolete.  Even sending an 8 ton payload to LEO, with say an 8-10 ton SEP propulsion system attached, that can get the 8 ton payload to GSO, there would be no need for Falcon heavy except for deep space payloads. 

Depends on what they throw their money into.   

A SEP propulsion system sounds like expensive hand waving of a 3rd stage.

I've been wondering how much the size and weight of a Raptor US will affect the F9 or FH central core booster stage. 
A 5+ meter Raptor US with a much larger mass will have huge impacts on loads on the booster.  I can't see this just plopping a new lego on top.

If you have to redesign the booster, why not go all in and design a raptor powered Mini-BFR or a shorter 5+ Meter Merlin powered F11,F13,F15 or what have you.  Opening up a wider window for RTLS and US recovery.

Being way off topic, I'll come back to the FH.  This very impressive rocket, by the time it becomes operational may only have a 4-5 year life, but it will be a hugely important lesson and capability for SpaceX.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/27/2016 04:12 pm
The answer re. FH is here:

https://forum.nasaspaceflight.com/index.php?topic=40165.0

So much for focusing mainly on F9 launch manifest.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/27/2016 04:34 pm
The answer re. FH is here:

https://forum.nasaspaceflight.com/index.php?topic=40165.0

So much for focusing mainly on F9 launch manifest.
Vindication! :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: andrewsdanj on 04/27/2016 07:30 pm
Just noticed on SpaceX's Facebook page... Image of FH doing its thing, a Red Dragon on Mars and talk of Dragons (plural!) headed Mars-wards as early as 2018. Even with MuskTime that's something special!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 04/27/2016 07:53 pm
Just noticed on SpaceX's Facebook page... Image of FH doing its thing, a Red Dragon on Mars and talk of Dragons (plural!) headed Mars-wards as early as 2018. Even with MuskTime that's something special!
See
http://forum.nasaspaceflight.com/index.php?topic=40165.0  (the discussion thread)
which will lead you to
https://www.nasaspaceflight.com/2016/04/spacex-debut-red-dragon-2018-mars-mission/ (the article)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 04/28/2016 12:00 am
The answer re. FH is here:

https://forum.nasaspaceflight.com/index.php?topic=40165.0

So much for focusing mainly on F9 launch manifest.
Vindication! :)

On oh-so-many levels...   Until it is rescheduled, happy Mars day!  :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 04/28/2016 12:06 am
I'm joining the party late, had a busy day.

There's more detail on FH in that rendering:

- The different legs on the center core
- The grid fins being located higher
- more?

The grin fin location seems to interact with that cross beam.  Can't tell it it's driven by it - it could also be evidence of some change in the side core length.

The leg clearance...  Why?  Is it because the center core is heavier?  Is it the hotter reentry?  The cross-structure at the bottom?  Sea-worthy landing gear vs. Land-worthy landing gear?




Are we discussing them elsewhere?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/28/2016 12:37 am
FH was the best solution to give SpaceX heavy lift in 2011. It's no longer the most efficient one if they believe they have the capability to skip straight to a raptor architecture

sometimes reality is just a bit more boring and straight-forward. FH needs to do one thing and one thing only. Have a successful test flight where it places an appropriate (Faring enshrouded) payload, dummy or otherwise into the appropriate orbit.

Regarding the Mars fantasies, those aren't even getting off center until there is a big juicy flow of profits.

The question is, is this contract for work on a Raptor for use on an US one of those pieces of evidence that is about to hit us in the face?

As the song goes........."Oh...what....a dif-frence..a.day..makes!!"
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 04/28/2016 12:39 am
I'm joining the party late, had a busy day.

There's more detail on FH in that rendering:

- The different legs on the center core
- The grid fins being located higher
- more?

The grin fin location seems to interact with that cross beam.  Can't tell it it's driven by it - it could also be evidence of some change in the side core length.

The leg clearance...  Why?  Is it because the center core is heavier?  Is it the hotter reentry?  The cross-structure at the bottom?  Sea-worthy landing gear vs. Land-worthy landing gear?

Are we discussing them elsewhere?
IF this render is indeed accurate, I can better understand, along with everything else we talk about why this beast has not come out from its lair yet.

Grid fins seem rotated off-center on the core as well. That strut definitely seemed to have forced a relocation.

Seems like the core legs were altered for the strut but...what if it's because of the hold-downs? There's only going to be 2 hold-downs for the center core so maybe they are oversized/larger and need more clearance from the bottom arch of the legs? Could also be the redesign for the ability to extend them sooner in the return profile to help with bleeding of some velocity?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 04/28/2016 12:45 am
FH was the best solution to give SpaceX heavy lift in 2011. It's no longer the most efficient one if they believe they have the capability to skip straight to a raptor architecture

sometimes reality is just a bit more boring and straight-forward. FH needs to do one thing and one thing only. Have a successful test flight where it places an appropriate (Faring enshrouded) payload, dummy or otherwise into the appropriate orbit.

The question is, is this contract for work on a Raptor for use on an US one of those pieces of evidence that is about to hit us in the face?

As the song goes........."Oh...what....a dif-frence..a.day..makes!!"
That post of mine was specifically in reference to them using a Dragon for their "first" test flight this fall. This Red Dragon will not be on their first test flight.

So I'm not really seeing your point with including it? Unless you believe that this news informs us that they will indeed put a Dragon on the FH test launch. But I see no such correlation.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/28/2016 12:53 am
I....don't like to see folks writing stuff like:

At the present point in time, the USAF has provided a way for Musk to get supplemental government funding for his Mars engine, and he's smart enough to start working on it sooner rather than later by making it a part of Falcon now, so that it's ready to be part of MCT a few more years down the road.
...when I'm fairly certain the USAF contract is due to Gwynne.  Would Elon chase these contracts without her?  Who knows---but a decent amount of the stuff attributed to "Musk" in Tom's post is not Elon's doing at all.

Musk..inspires.... there's a reason he's called the real life Tony Stark, after all.. He inspires his cadre of brilliant associates who design the things, sell the launches, deliver operational excellence, etc. But he *also* inspires those check writing billionaires. There is a good chance (at least 10%) that perfect storm of reality bending he's created will last until the Mars liners are flying regularly. Maybe not, but it's the way I'm betting.

Lar (and other recent posts here) touch on something that seems obvious to me: Elon is both different but then again not different from many of us who post here......I want to see him succeed. At any point along the way it may fracture and fall apart, but as long as it doesn't he is making progress in a way no one else can.

to quote Tennyson:

Come, my friends,
’Tis not too late to seek a newer world.
Push off, and sitting well in order smite
The sounding furrows; for my purpose holds
To sail beyond the sunset, and the baths
Of all the western stars, until I die.
It may be that the gulfs will wash us down:
It may be we shall touch the Happy Isles,
And see the great Achilles, whom we knew.
Tho’ much is taken, much abides; and tho’
We are not now that strength which in old days
Moved earth and heaven, that which we are, we are;
One equal temper of heroic hearts,
Made weak by time and fate, but strong in will
To strive, to seek, to find, and not to yield.

It is not Musk forcing us to do this, it is those romantic enough to see that Musk is the practical embodiment of what needs to be done to allow it that would force ourselves to go along.

It's what Lar and Nadreck said. They got it right.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: zubenelgenubi on 04/28/2016 01:03 am
<snip>
So, to quote Tennyson:

Come, my friends,
’Tis not too late to seek a newer world.
Push off, and sitting well in order smite
The sounding furrows; for my purpose holds
To sail beyond the sunset, and the baths
Of all the western stars, until I die.
It may be that the gulfs will wash us down:
It may be we shall touch the Happy Isles,
And see the great Achilles, whom we knew.
Tho’ much is taken, much abides; and tho’
We are not now that strength which in old days
Moved earth and heaven, that which we are, we are;
One equal temper of heroic hearts,
Made weak by time and fate, but strong in will
To strive, to seek, to find, and not to yield.
<snip>
To quote Sheridan, from a note left by Sinclair, quoting Tennyson:
https://www.youtube.com/watch?v=Y4Leug60NYg (https://www.youtube.com/watch?v=Y4Leug60NYg)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 04/28/2016 01:31 am
A Falcon 9 v1.2 with a metholox Raptor upper stage expendable can get about 28 tons to orbit, and about 20 tons for RTLS.  This may make the lower throw weight heavies obsolete.  Even sending an 8 ton payload to LEO, with say an 8-10 ton SEP propulsion system attached, that can get the 8 ton payload to GSO, there would be no need for Falcon heavy except for deep space payloads. 

Depends on what they throw their money into.

No need for SEP if you have a high-energy upper stage. Throw that thing straight to GTO. I think Raptor and 2nd stage recovery will both debut on Heavy launches though. Not sure how much more mass you can put atop a single stick F9. Fineness and T/W ratios are much better on Heavy.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GWH on 04/28/2016 02:07 am
 >:( Can we PLEASE move the Raptor upper stage to another thread?!?
Such as here: http://forum.nasaspaceflight.com/index.php?topic=39310.0
or here: http://forum.nasaspaceflight.com/index.php?topic=39314.0
Yes it could have a lot of potential but at this point it isn't even a paper rocket - literally a few sentences in an Airforce press release.

SpaceX just released a new rendering of the FH, as pointed out there some variances from the last rendering's.

The fact that it shows recovery hardware is quite interesting, seeing as how Elon previously tweeted the FH would be in expendable mode to get a fully loaded D2 to mars:
https://twitter.com/elonmusk/status/643538701981716481?lang=en


MeekGee, rCoppola: Leg change and early deployment lets them deploy sooner opens up enough dV to pull off full 3 core recovery?  Musk alluded to mods for early deployment in previous twitter storms.  Given the changes to the rendering I can't help but think legs were intentional.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 04/28/2016 07:01 am


As the song goes........."Oh...what....a dif-frence..a.day..makes!!"

Yup! Nothing like finding your attempt to measure your extreme optimism into realism actually turned out as deludedly pessimistic. Within several hours of posting.  ;D
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 04/28/2016 07:13 am


As the song goes........."Oh...what....a dif-frence..a.day..makes!!"

Yup! Nothing like finding your attempt to measure your extreme optimism into realism actually turned out as deludedly pessimistic. Within several hours of posting.  ;D

You're in the SpaceX section.  This sort of thing tends to happen here every few months...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Saabstory88 on 04/28/2016 01:59 pm
On the topic of the rendering...

This is not a technical model. If you look closely, the details are cobbled together from assets. The center legs are identical to the original F9R-Dev1 legs. Does this mean that they have discovered something and are going back to old versions? Probably not. Take a look at the nosecone in the model, and take a really good look at the physical nosecones we have seen on the factory floor. The real ones have a straight barrel section before the curve to accommodate the grid fins and thrusters. Take a look at the grid fins themselves on this model. They still have the old aeroshells which have since been ditched.

The pojnt is, I don't think we can glean  any new info from this model. Its simply PR  material.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 04/28/2016 02:14 pm
On the topic of the rendering...

This is not a technical model. If you look closely, the details are cobbled together from assets. The center legs are identical to the original F9R-Dev1 legs. Does this mean that they have discovered something and are going back to old versions? Probably not. Take a look at the nosecone in the model, and take a really good look at the physical nosecones we have seen on the factory floor. The real ones have a straight barrel section before the curve to accommodate the grid fins and thrusters. Take a look at the grid fins themselves on this model. They still have the old aeroshells which have since been ditched.

The pojnt is, I don't think we can glean  any new info from this model. Its simply PR  material.
Ok, but the flip argument:

What would posses a graphics artist to use different legs for just the middle core?

Or to both raise and shift sideways (with a twist) the grid fins?


This is a bit like the F9.1 picture of (what was it?) 2-3 years ago, where people were speculating that the new engine arrangement was just inaccuracies by a graphics designer....

Oh, or the covered up FSS and L/E

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GWH on 04/28/2016 02:23 pm
Interesting points. I normally wouldn't be so quick to over analyze an artistic rendering. What stuck out at me was that they already had a full model of the FH as seen in their last video, so why change it if they only needed to swap the fairing to a dragon? In that video the FH had fins at same height all 3 cores and same legs. Checking the website FH is the same but F9 has the different legs you note. So it could very well be a cobbled together model, grid fin height is still wierd but again maybe the stock F9 model didn't match height of stock FH model
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Saabstory88 on 04/28/2016 02:26 pm
Ok, but the flip argument:

What would posses a graphics artist to use different legs for just the middle core?

Or to both raise and shift sideways (with a twist) the grid fins?


This is a bit like the F9.1 picture of (what was it?) 2-3 years ago, where people were speculating that the new engine arrangement was just inaccuracies by a graphics designer....

Oh, or the covered up FSS and L/E

Having made graphics for corporate clients, two main factors come into play

1. Unfamiliarity with technical details
2. Staff turnover

Given SpaceX's employment practices, I'd suspect the latter.

Also, go back and look through SpaceX's flickr page. Old renderings with wrong legs on a single stick as well... It's just lazy mixing of assets, nothing more, evidenced by the repourposed grasshopper model as a lightning tower...

https://www.flickr.com/photos/spacex/21048044876/
https://www.flickr.com/photos/spacex/20886182720/in/photostream/
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 04/28/2016 02:30 pm
I believe the side boosters won't have a full interstage, so where are the grid fins going to go? Will there be a rump interstage? Something that has the nose cone integrated as well (but then you get into how does the lifting fixture attach and all sorts of other fun engineering details)?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 04/28/2016 02:31 pm
Ok, but the flip argument:

What would posses a graphics artist to use different legs for just the middle core?

Or to both raise and shift sideways (with a twist) the grid fins?


This is a bit like the F9.1 picture of (what was it?) 2-3 years ago, where people were speculating that the new engine arrangement was just inaccuracies by a graphics designer....

Oh, or the covered up FSS and L/E

Having made graphics for corporate clients, two main factors come into play

1. Unfamiliarity with technical details
2. Staff turnover

Given SpaceX's employment practices, I'd suspect the latter.

Also, go back and look through SpaceX's flickr page. Old renderings with wrong legs on a single stick as well... It's just lazy mixing of assets, nothing more, evidenced by the repourposed grasshopper model as a lightning tower...

https://www.flickr.com/photos/spacex/21048044876/
https://www.flickr.com/photos/spacex/20886182720/in/photostream/
None of this explains why the GA made more work for themselves instead of simple patterning 3 in a row...

And what "employment practices"?   Are on the "SpaceX is a sweatshop" thing?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Ronsmytheiii on 04/28/2016 02:33 pm
Falcon Heavy has been built; finishing touches are being put on. Wait a couple months, you'll see tests.


I am sorry, but I have to disagree with this. Falcon Heavy has not gone out to the pad, there has not been a static fire, it hasn't been fabricated, even individual critical components haven't been tested yet. LC-39 is not done yet, McGregor still is constructing hangar space and so on. Heavy has a long way to go, the "finishing touches" won't happen until after the first flight.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 04/28/2016 02:43 pm
The engine arraignment pic wasn't a PR photo, it was from some customer document
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Saabstory88 on 04/28/2016 02:43 pm

None of this explains why the GA made more work for themselves instead of simple patterning 3 in a row...

And what "employment practices"?   Are on the "SpaceX is a sweatshop" thing?

No simply talking about turnover. New artist comes in, and uses some of the assets from the old guy, and some of his own. Nothing more complicated than that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: ugordan on 04/28/2016 02:48 pm
The engine arraignment pic wasn't a PR photo, it was from some customer document

And it was pretty obvious it wasn't a rendering made for PR purposes like this, but more of a schematic of the vehicle. I'd put the accuracy of details in this rendering in the same category as the black legs and the SpaceX decal size.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 04/28/2016 03:15 pm
The engine arraignment pic wasn't a PR photo, it was from some customer document

And it was pretty obvious it wasn't a rendering made for PR purposes like this, but more of a schematic of the vehicle. I'd put the accuracy of details in this rendering in the same category as the black legs and the SpaceX decal size.
If they had shown three identical cores, for example, I'd say yes - lazy graphics designer, copy paste, etc.

But show me the graphics designer that on purpose makes the rocket more complex, actually adding variance on their own accord....

And back in the F9.1 days, or the covered LE case, lots of people argued it was only graphics designer fancy.

I'd give it better than even odds that there's something to this.

Someone made a CAD model that had two types of legs, and there's no obvious graphics reason why that is.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GWH on 04/28/2016 03:41 pm
Just to better define the differences here are the 2 renderings as per SpaceX website side by side and overlaid and scaled based on core diameter.  Shows the difference in legs between F9 and FH, grid fin placement at same height.
So the grid fin height is weird to have changed but could have just been a minor update to the F9 model not shown and getting caught up in whether the image released yesterday is indicative of FH changes and 3-core recovery on a Dragon to Mars is probably very much premature.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: starsilk on 04/28/2016 03:42 pm
FH was the best solution to give SpaceX heavy lift in 2011. It's no longer the most efficient one if they believe they have the capability to skip straight to a raptor architecture

sometimes reality is just a bit more boring and straight-forward. FH needs to do one thing and one thing only. Have a successful test flight where it places an appropriate (Faring enshrouded) payload, dummy or otherwise into the appropriate orbit.

The question is, is this contract for work on a Raptor for use on an US one of those pieces of evidence that is about to hit us in the face?

As the song goes........."Oh...what....a dif-frence..a.day..makes!!"
That post of mine was specifically in reference to them using a Dragon for their "first" test flight this fall. This Red Dragon will not be on their first test flight.

I would say this announcement makes it much more likely that the test flight will be throwing a Dragon around the moon. testing BEO Dragon, deep space comms, hot re-entry.

by the time the FH first flies, they'll have a little over a year before the real deal.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: testguy on 04/28/2016 04:34 pm
FH was the best solution to give SpaceX heavy lift in 2011. It's no longer the most efficient one if they believe they have the capability to skip straight to a raptor architecture

sometimes reality is just a bit more boring and straight-forward. FH needs to do one thing and one thing only. Have a successful test flight where it places an appropriate (Faring enshrouded) payload, dummy or otherwise into the appropriate orbit.

The question is, is this contract for work on a Raptor for use on an US one of those pieces of evidence that is about to hit us in the face?

As the song goes........."Oh...what....a dif-frence..a.day..makes!!"
That post of mine was specifically in reference to them using a Dragon for their "first" test flight this fall. This Red Dragon will not be on their first test flight.

I would say this announcement makes it much more likely that the test flight will be throwing a Dragon around the moon. testing BEO Dragon, deep space comms, hot re-entry.

by the time the FH first flies, they'll have a little over a year before the real deal.

I agree.  It does not have to be a Dragon 2.  Can't they get most of the data with a reused Dragon 1?  Reusing a Dragon would be a real statement in and of itself.  If you don't reach you never get to the stars!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: darkenfast on 04/29/2016 06:05 am
The exhaust from the rocket appears to be going out both sides of Pad 39A, which is completely wrong, so I wouldn't put too much faith in the rest of the rendering.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 04/29/2016 07:00 am
Can that first flight use a Dragon and a fairing? I can imagine that they use the same connecting points and are incompatible.

They will want a fairing for the flight to count for Air Force certification.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Semmel on 04/29/2016 09:14 am
According to the Falcon9 User Guide, the payload adapter can only hold 10885 kg (Section 3.3). Dragon 2 plus fuel plus payload plus trunk plus trunk equipment in the trunk should be heavier.

The user guide states that for heavier payloads, the communication with SpaceX is required, which should not be a problem in this case. What I want to say, its not that simple even if Dragon would fit inside.

If the payload adapter for FH is identical to F9, it is probably capable of lofting a heavy up to 8mT GTO satellite to its target orbit, but it cant lift the theoretical LEO lifting mass. A redesign of the adapter is required for that. Not impossible but more work than you might expect. Not sure the second stage needs a stiffening as well for more than 10 mT payloads.

User Guide:
http://www.spacex.com/sites/spacex/files/falcon_9_users_guide_rev_2.0.pdf
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 04/29/2016 10:10 am
According to the Falcon9 User Guide, the payload adapter can only hold 10885 kg (Section 3.3). Dragon 2 plus fuel plus payload plus trunk plus trunk equipment in the trunk should be heavier.

The user guide states that for heavier payloads, the communication with SpaceX is required, which should not be a problem in this case. What I want to say, its not that simple even if Dragon would fit inside.

They would not need a lot of payload and they would not need to have it fully fuelled. They don't have to do orbit change, only course corrections, assuming it is in a free return trajectory.

Edit: I am not thinking of a Red Dragon. I am thinking of a possible cargo Dragon for a moon flyby on the maiden voyage of Falcon Heavy and using a payload fairing additionally just to make it a valid qualification flight for DOD certification, not because it might be needed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Semmel on 04/29/2016 12:35 pm
They would not need a lot of payload and they would not need to have it fully fuelled. They don't have to do orbit change, only course corrections, assuming it is in a free return trajectory.

Edit: I am not thinking of a Red Dragon. I am thinking of a possible cargo Dragon for a moon flyby on the maiden voyage of Falcon Heavy and using a payload fairing additionally just to make it a valid qualification flight for DOD certification, not because it might be needed.

Yeah, I understand what you say. But to test FH, I imagined it to lift a payload/mass simulator/moon-circling dragon on a mission that would be impossible with a normal F9. Thats why I made my comment about the fairing adapter. Sorry, I forgot to state that assumption in my text.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: intrepidpursuit on 04/29/2016 01:53 pm
I'm still voting for putting a school bus in lunar orbit. With a wheel of cheese in it.

In all seriousness, they don't have flight ready Dragon 2s yet and putting a CRS-1 Dragon around the moon wouldn't prove much. Would be great to land a Dragon 2 on the moon, that would prove a point, but they don't have one. They need the fairing for USAF cert anyway. That is a real business requirement. I'm sure they'll have some real satellites aboard, but they'll be riding on a giant concrete block.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: PahTo on 04/29/2016 01:53 pm

Semmel and I are thinking along the same lines.  Put a Dragon of any flavor around the moon (either figure 8 or a few orbits) and return off the Cali coast.  A few photos/movies from close above the moon, test many elements of the vehicle(s) and first demo of heat shield at high(er) velocity.  Would make a huge PR splash (first pun of the day).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Brovane on 04/29/2016 02:03 pm
I'm still voting for putting a school bus in lunar orbit. With a wheel of cheese in it.

In all seriousness, they don't have flight ready Dragon 2s yet and putting a CRS-1 Dragon around the moon wouldn't prove much. Would be great to land a Dragon 2 on the moon, that would prove a point, but they don't have one. They need the fairing for USAF cert anyway. That is a real business requirement. I'm sure they'll have some real satellites aboard, but they'll be riding on a giant concrete block.

It would test the TPS of the Dragon.  It would generate press if they did loft a Dragonv1 in a lunar free return trajectory. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: intrepidpursuit on 04/29/2016 02:11 pm
I'm still voting for putting a school bus in lunar orbit. With a wheel of cheese in it.

In all seriousness, they don't have flight ready Dragon 2s yet and putting a CRS-1 Dragon around the moon wouldn't prove much. Would be great to land a Dragon 2 on the moon, that would prove a point, but they don't have one. They need the fairing for USAF cert anyway. That is a real business requirement. I'm sure they'll have some real satellites aboard, but they'll be riding on a giant concrete block.

It would test the TPS of the Dragon.  It would generate press if they did loft a Dragonv1 in a lunar free return trajectory.

It would test the TPS of Dragon 1. Dragon 2 will at very least have a different tile layout to handle the legs and it being a totally different vehicle the mass centers are likely different. Plus they have improved Pica-X several times so I wouldn't doubt Dragon 2 has a new version. So it doesn't really prove anything.

They have plenty of press. If would fail to prove the rocket for the USAF purposes which is much more important than further press saying "we can do something pointless".
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: BobHk on 04/29/2016 03:04 pm
FH was the best solution to give SpaceX heavy lift in 2011. It's no longer the most efficient one if they believe they have the capability to skip straight to a raptor architecture

sometimes reality is just a bit more boring and straight-forward. FH needs to do one thing and one thing only. Have a successful test flight where it places an appropriate (Faring enshrouded) payload, dummy or otherwise into the appropriate orbit.

The question is, is this contract for work on a Raptor for use on an US one of those pieces of evidence that is about to hit us in the face?

As the song goes........."Oh...what....a dif-frence..a.day..makes!!"
That post of mine was specifically in reference to them using a Dragon for their "first" test flight this fall. This Red Dragon will not be on their first test flight.

I would say this announcement makes it much more likely that the test flight will be throwing a Dragon around the moon. testing BEO Dragon, deep space comms, hot re-entry.

by the time the FH first flies, they'll have a little over a year before the real deal.

Why use a Dragon when they have a perfectly good Dragon V2 they can kit for the moon or Mars....

https://www.youtube.com/watch?v=07Pm8ZY0XJI
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: intrepidpursuit on 04/29/2016 03:15 pm
FH was the best solution to give SpaceX heavy lift in 2011. It's no longer the most efficient one if they believe they have the capability to skip straight to a raptor architecture

sometimes reality is just a bit more boring and straight-forward. FH needs to do one thing and one thing only. Have a successful test flight where it places an appropriate (Faring enshrouded) payload, dummy or otherwise into the appropriate orbit.

The question is, is this contract for work on a Raptor for use on an US one of those pieces of evidence that is about to hit us in the face?

As the song goes........."Oh...what....a dif-frence..a.day..makes!!"
That post of mine was specifically in reference to them using a Dragon for their "first" test flight this fall. This Red Dragon will not be on their first test flight.

I would say this announcement makes it much more likely that the test flight will be throwing a Dragon around the moon. testing BEO Dragon, deep space comms, hot re-entry.

by the time the FH first flies, they'll have a little over a year before the real deal.

Why use a Dragon when they have a perfectly good Dragon V2 they can kit for the moon or Mars....

https://www.youtube.com/watch?v=07Pm8ZY0XJI

That is not even close to a flight article. It is a dragon 1 with part rearranged to include the SD thrusters. The windows are reflective metal.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: BobHk on 04/29/2016 03:31 pm
FH was the best solution to give SpaceX heavy lift in 2011. It's no longer the most efficient one if they believe they have the capability to skip straight to a raptor architecture

sometimes reality is just a bit more boring and straight-forward. FH needs to do one thing and one thing only. Have a successful test flight where it places an appropriate (Faring enshrouded) payload, dummy or otherwise into the appropriate orbit.

The question is, is this contract for work on a Raptor for use on an US one of those pieces of evidence that is about to hit us in the face?

As the song goes........."Oh...what....a dif-frence..a.day..makes!!"
That post of mine was specifically in reference to them using a Dragon for their "first" test flight this fall. This Red Dragon will not be on their first test flight.

I would say this announcement makes it much more likely that the test flight will be throwing a Dragon around the moon. testing BEO Dragon, deep space comms, hot re-entry.

by the time the FH first flies, they'll have a little over a year before the real deal.

Why use a Dragon when they have a perfectly good Dragon V2 they can kit for the moon or Mars....

https://www.youtube.com/watch?v=07Pm8ZY0XJI

That is not even close to a flight article. It is a dragon 1 with part rearranged to include the SD thrusters. The windows are reflective metal.

SpaceX calls it a Dragon 2, please indicate how you claim to state otherwise?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: intrepidpursuit on 04/29/2016 03:59 pm

Why use a Dragon when they have a perfectly good Dragon V2 they can kit for the moon or Mars....

https://www.youtube.com/watch?v=07Pm8ZY0XJI

That is not even close to a flight article. It is a dragon 1 with parts rearranged to include the SD thrusters. The windows are reflective metal.

SpaceX calls it a Dragon 2, please indicate how you claim to state otherwise?

It is an engineering test article built up from a Dragon 1 pressure vessel. it is the same like the ones they used for drop and abort testing testing earlier in the regime. It is no more a flight article than Enterprise was. If they want a full up D2 that is flight worthy they'd have to build one, and the design isn't even fully complete yet.

*EDIT: It does seem that which vehicle this is has not been confirmed. (well, there's this: http://forum.nasaspaceflight.com/index.php?topic=36967.msg1438350#msg1438350). It is clear though that the windows are metallic just as they were on the abort test vehicle (http://www.spacex.com/news/2015/05/04/5-things-know-about-spacexs-pad-abort-test), so that indicates that this is not a finished Dragon 2. Plus there is the rub of the design not yet being done.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: starsilk on 04/29/2016 04:21 pm
FH was the best solution to give SpaceX heavy lift in 2011. It's no longer the most efficient one if they believe they have the capability to skip straight to a raptor architecture

sometimes reality is just a bit more boring and straight-forward. FH needs to do one thing and one thing only. Have a successful test flight where it places an appropriate (Faring enshrouded) payload, dummy or otherwise into the appropriate orbit.

The question is, is this contract for work on a Raptor for use on an US one of those pieces of evidence that is about to hit us in the face?

As the song goes........."Oh...what....a dif-frence..a.day..makes!!"
That post of mine was specifically in reference to them using a Dragon for their "first" test flight this fall. This Red Dragon will not be on their first test flight.

I would say this announcement makes it much more likely that the test flight will be throwing a Dragon around the moon. testing BEO Dragon, deep space comms, hot re-entry.

by the time the FH first flies, they'll have a little over a year before the real deal.

Why use a Dragon when they have a perfectly good Dragon V2 they can kit for the moon or Mars....

https://www.youtube.com/watch?v=07Pm8ZY0XJI

That is not even close to a flight article. It is a dragon 1 with part rearranged to include the SD thrusters. The windows are reflective metal.

SpaceX calls it a Dragon 2, please indicate how you claim to state otherwise?

It is an engineering test article built up from a Dragon 1 pressure vessel. it is the same one they used for drop testing testing earlier in the regime (and the abort test?). It is no more a flight article then enterprise was. If they want a full up D2 that is flight worthy they'd have to build one, and the design isn't even fully complete yet.

they just publicly set themselves a hard deadline, can't miss that one unless you're happy with waiting two years.

the clock is running. tick tock.

it seems highly unlikely to me that SpaceX would be dumb enough to throw a collection of untested hardware at Mars. they have a big habit of using other missions to do tests of their 'background projects'. FH test launch is currently a large write-off cost, particularly since they can't seem to find anyone willing to put their expensive satellite on it.

build a Dragon 2, or use the test article. they're testing pica-x (if the test article doesn't have 'Dragon 2' pica, change it). they're testing BEO comms, radiation protection, solar panels, long distance command and control. none of those need it to be a 'perfect' dragon 2, particularly when Red Dragon is clearly going to be a 'modified' version in various ways - all the BEO stuff will be new for starters. so what does it matter if it's installed in a modified dragon, or a brand new dragon 2?

more important is whether they need to demonstrate with the fairing or not, and if they do, whether they can fit a dragon inside the fairing.

oh, we should probably add the rumors of a larger fairing to that recipe...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: intrepidpursuit on 04/29/2016 04:50 pm
they just publicly set themselves a hard deadline, can't miss that one unless you're happy with waiting two years.

the clock is running. tick tock.

it seems highly unlikely to me that SpaceX would be dumb enough to throw a collection of untested hardware at Mars. they have a big habit of using other missions to do tests of their 'background projects'. FH test launch is currently a large write-off cost, particularly since they can't seem to find anyone willing to put their expensive satellite on it.

build a Dragon 2, or use the test article. they're testing pica-x (if the test article doesn't have 'Dragon 2' pica, change it). they're testing BEO comms, radiation protection, solar panels, long distance command and control. none of those need it to be a 'perfect' dragon 2, particularly when Red Dragon is clearly going to be a 'modified' version in various ways - all the BEO stuff will be new for starters. so what does it matter if it's installed in a modified dragon, or a brand new dragon 2?

more important is whether they need to demonstrate with the fairing or not, and if they do, whether they can fit a dragon inside the fairing.

oh, we should probably add the rumors of a larger fairing to that recipe...

We know they need to demonstrate the fairing for USAF certification. On the rest we will just have to see what they do. You think they'll send an unfinished test article around the moon. I think they'll focus on the mission at hand with some small payloads and the experimental booster landings.

I am keeping a close eye out for any payload announcements as that could clarify some things in advance of the launch and also could shed light on when they will actually launch this beast.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 04/29/2016 08:24 pm
Why is fairing testing needed?
F9 fairing is moving over to FH unchanged (excepting new, larger version) and should benefit from significant operational experience on a certified vehicle.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/29/2016 10:27 pm
It is no more a flight article thean Eenterprise was

Enterprise actually was built to fly. They originally planned to refurbish her in the same manner they did the other shuttles when they were rebuilt. By the time Atlantis was finished, the airframes had become so much lighter that they decided Enterprise's higher mass would not allow the payloads the others offered, so they decided not to retrofit her. After STS-51L, they almost refurbished Enterprise, but in the end decided they had enough spare parts to build Endeavor.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 04/30/2016 01:47 am
I'm still voting for putting a school bus in lunar orbit.

Imagine the STEM inspiration!

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 04/30/2016 02:00 am
I'm still voting for putting a school bus in lunar orbit.

Imagine the STEM inspiration!
https://youtu.be/kVtI_j-QUq8
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hamerad on 04/30/2016 07:56 am
Elon musk confirming recovery of all 3 cores on first fh

https://twitter.com/elonmusk/status/726301598398312448

Quote

Danny S. Parker ‏@dannysparker  6h6 hours ago
@elonmusk For 1st launch of Falcon Hvy will there be effort to simultaneously land all 3 booster stages?  #FalconHeavy

Elon MuskVerified account
‏@elonmusk
@dannysparker yes


Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mvpel on 04/30/2016 12:26 pm
I beg of you, please trim your quotes. Everything you're quoting is immediately available above your post.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 04/30/2016 02:20 pm
The SpaceX FH web page has been updated with new performance values:
http://www.spacex.com/falcon-heavy (http://www.spacex.com/falcon-heavy)

13,600 kg to Mars
22,200 kg to GTO
54,400 kg to LEO

Just missing the Moon value. Should be somewhere between the Mars and GTO and higher than the earlier 18,000 kg value for 1.1 since these are > than those for Mars and GTO.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 04/30/2016 02:24 pm
The SpaceX FH web page has been updated with new performance values:
http://www.spacex.com/falcon-heavy (http://www.spacex.com/falcon-heavy)

13,600 kg to Mars
22,200 kg to GTO
54,400 kg to LEO

Just missing the Moon value. Should be somewhere between the Mars and GTO and higher than the earlier 18,000 kg value for 1.1 since these are > than those for Mars and GTO.

[buff fingernails against lapel]And presumably without cross feed ... http://forum.nasaspaceflight.com/index.php?topic=39181.msg1521480#msg1521480 (http://forum.nasaspaceflight.com/index.php?topic=39181.msg1521480#msg1521480) [/buff fingernails against lapel]
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mongo62 on 04/30/2016 02:25 pm
The SpaceX FH web page has been updated with new performance values:
http://www.spacex.com/falcon-heavy (http://www.spacex.com/falcon-heavy)

13,600 kg to Mars
22,200 kg to GTO
54,400 kg to LEO

Just missing the Moon value. Should be somewhere between the Mars and GTO and higher than the earlier 18,000 kg value for 1.1 since these are > than those for Mars and GTO.

Which makes a Dragon 2 lunar orbital mission (perhaps including a small inflatable hab module) quite feasible, maybe even with the side boosters recoverable.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Rebel44 on 04/30/2016 02:56 pm
I'm still voting for putting a school bus in lunar orbit. With a wheel of cheese in it.

With updated stats, they can put T-72 tank on orbit (at expendable configuration)  :o
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: woods170 on 04/30/2016 03:30 pm
The SpaceX FH web page has been updated with new performance values:
http://www.spacex.com/falcon-heavy (http://www.spacex.com/falcon-heavy)

13,600 kg to Mars
22,200 kg to GTO
54,400 kg to LEO

Just missing the Moon value. Should be somewhere between the Mars and GTO and higher than the earlier 18,000 kg value for 1.1 since these are > than those for Mars and GTO.

2,900 kg to Pluto

Looks like SpaceX is now soliciting for beyond-Mars missions as well...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: S.Paulissen on 04/30/2016 04:24 pm
2,900 kg to Pluto

Looks like SpaceX is now soliciting for beyond-Mars missions as well...

That's really big with no gravity assists.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Rebel44 on 04/30/2016 04:26 pm
2,900 kg to Pluto

Looks like SpaceX is now soliciting for beyond-Mars missions as well...

That's really big with no gravity assists.

IMO, thats a number with gravity assist
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rocx on 04/30/2016 04:39 pm
http://www.spacex.com/falcon-heavy (http://www.spacex.com/falcon-heavy)
54,400 kg to LEO

[buff fingernails against lapel]And presumably without cross feed ... http://forum.nasaspaceflight.com/index.php?topic=39181.msg1521480#msg1521480 (http://forum.nasaspaceflight.com/index.php?topic=39181.msg1521480#msg1521480) [/buff fingernails against lapel]
Disagree, the quoted website says
Quote
For missions involving exceptionally heavy payloads—greater than 45,000 kilograms or 100,000 pounds—Falcon Heavy offers a unique cross-feed propellant system.
And 54,400 is more than 45,000. I therefore suppose that the other maxima also are with crossfeed. Furthermore Gwynne Shotwell has said that crossfeed is not yet developed, but may be if there is demand for it, so the numbers on this page are quite theoretical.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AllenB on 04/30/2016 04:47 pm
The SpaceX FH web page has been updated with new performance values:
http://www.spacex.com/falcon-heavy (http://www.spacex.com/falcon-heavy)

13,600 kg to Mars
22,200 kg to GTO
54,400 kg to LEO

Just missing the Moon value. Should be somewhere between the Mars and GTO and higher than the earlier 18,000 kg value for 1.1 since these are > than those for Mars and GTO.

There's something else interesting about that page. Maybe it's been there for a while and discussed previously; if so I apologize for not finding it. As expected, the text under "FIRST STAGE" tells us "27 Merlin engines, generate 20,418 kilonewtons (4.59 million pounds) of thrust at liftoff" which fits in with the known Merlin 1D thrust as well as the "about 1.5 million pounds" generally thrown around for the current Falcon 9 at liftoff.

Then comes the interesting (or incorrect) part. Right after that some stats are given:

CORES
3
ENGINES
27
THRUST AT SEA LEVEL
22,819kN    5,130,000 lbf
THRUST IN VACUUM
24,897kN    5,548,500 lbf

Some quick division yields 190,000 lbf per engine at sea level and 205,500 in vacuum (not far short of Mvac 1D). Could this be right? It doesn't seem like a typo as both figures yield nice, round numbers per engine. Yet it's also quite a bit more than the current known thrust level (and that promised for Falcon Heavy just a few lines up.)

Thoughts? Are they planning (yet) another bump to 1D performance? Is this a website designer who had a few drinks at lunch? Either way, seems kind of interesting.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 04/30/2016 04:55 pm
Its more the tables were updated but not the text in some places. It may be months before all the values on the various pages become consistent.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Rebel44 on 04/30/2016 04:55 pm
The SpaceX FH web page has been updated with new performance values:
http://www.spacex.com/falcon-heavy (http://www.spacex.com/falcon-heavy)

13,600 kg to Mars
22,200 kg to GTO
54,400 kg to LEO

Just missing the Moon value. Should be somewhere between the Mars and GTO and higher than the earlier 18,000 kg value for 1.1 since these are > than those for Mars and GTO.

There's something else interesting about that page. Maybe it's been there for a while and discussed previously; if so I apologize for not finding it. As expected, the text under "FIRST STAGE" tells us "27 Merlin engines, generate 20,418 kilonewtons (4.59 million pounds) of thrust at liftoff" which fits in with the known Merlin 1D thrust as well as the "about 1.5 million pounds" generally thrown around for the current Falcon 9 at liftoff.

Then comes the interesting (or incorrect) part. Right after that some stats are given:

CORES
3
ENGINES
27
THRUST AT SEA LEVEL
22,819kN    5,130,000 lbf
THRUST IN VACUUM
24,897kN    5,548,500 lbf

Some quick division yields 190,000 lbf per engine at sea level and 205,500 in vacuum (not far short of Mvac 1D). Could this be right? It doesn't seem like a typo as both figures yield nice, round numbers per engine. Yet it's also quite a bit more than the current known thrust level (and that promised for Falcon Heavy just a few lines up.)

Thoughts? Are they planning (yet) another bump to 1D performance? Is this a website designer who had a few drinks at lunch? Either way, seems kind of interesting.

as I posted here: http://forum.nasaspaceflight.com/index.php?topic=39180.280

Based on updated F9 1st stage Thrust at sea level and Thrust In Vacuum:
Merlin 1D+ thrust at sea level: 190 000lbf
Merlin 1D+ thrust in vacuum: 205 500lbf

So, if engines weight didnt change (1,030 lb), its trust-to-weight ratio is now 199.5  :o 8)

All performance numbers published in this update are quite shocking - I didnt think they can increase Merlin 1D+ performance that much.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: ugordan on 04/30/2016 04:58 pm
Why would you even assume that the engine mass didn't change? Improvements rarely come for free.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: camelNotation on 04/30/2016 05:00 pm
Some quick division yields 190,000 lbf per engine at sea level and 205,500 in vacuum (not far short of Mvac 1D). Could this be right? It doesn't seem like a typo as both figures yield nice, round numbers per engine. Yet it's also quite a bit more than the current known thrust level (and that promised for Falcon Heavy just a few lines up.)

Thoughts? Are they planning (yet) another bump to 1D performance? Is this a website designer who had a few drinks at lunch? Either way, seems kind of interesting.

I'm a little skeptical that they would do a thrust upgrade less than a year after the last thrust upgrade. Also strange that the M1D vac was not upgraded from 210,000 lbf thrust. SpaceX usually upgrades both at the same time.

Slightly off topic, but the Falcon 9 engine thrust figures calculate to the same thrust-per-engine you calculated, but the stage burn time is still 162s. Either the stage got longer, the burn time figure is too high, or the thrust is too high.

Probably best to take this with a grain of salt until additional, official confirmation.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 04/30/2016 05:04 pm
The pricing/capabilities page also lists F9 as 28,800kg to LEO.
This is inconsistent with FH at 54,400... so, one number is wrong or they are comparing apples to oranges.

Assuming that the F9 28,800kg is full expendable, shouldn't the equivalent FH number be north of 80,000kg?
Using the 3x gross approximation, 28,800x3=86,400kg.

http://www.spacex.com/about/capabilities
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 04/30/2016 05:06 pm
My guess is the 54 tonnes is disposable with cross-feed. I want to know what she will do with Raptor-US.

And the tables are copied from old graphics without being updated.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AllenB on 04/30/2016 05:13 pm
as I posted here: http://forum.nasaspaceflight.com/index.php?topic=39180.280

Based on updated F9 1st stage Thrust at sea level and Thrust In Vacuum:
Merlin 1D+ thrust at sea level: 190 000lbf
Merlin 1D+ thrust in vacuum: 205 500lbf

So, if engines weight didnt change (1,030 lb), its trust-to-weight ratio is now 199.5  :o 8)

All performance numbers published in this update are quite shocking - I didnt think they can increase Merlin 1D+ performance that much.

Missed that entirely, thanks. My search-foo is weak indeed. Very exciting stuff!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Rebel44 on 04/30/2016 05:13 pm
Why would you even assume that the engine mass didn't change? Improvements rarely come for free.

IIRC, engine weight didnt change (or very little) between Merlin 1C and 1D
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TrevorMonty on 04/30/2016 05:17 pm
The US supports GSO missions, this is capability that ULA have been pushing for their LVs.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Rebel44 on 04/30/2016 05:38 pm
How can the Falcon 9 numbers keep increasing (by more than 100% at this point) but FH numbers have stayed the same since 2011?

Early, SpaceX wanted to use fuel crossfeed for FH, but engine performance increases allowed them to keep FH numbers, without need to develop fuel crossfeed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 04/30/2016 05:46 pm
Why would you even assume that the engine mass didn't change? Improvements rarely come for free.

IIRC, engine weight didnt change (or very little) between Merlin 1C and 1D

Actually engine mass went down from Merlin 1C to Merlin 1D.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TrueBlueWitt on 04/30/2016 06:34 pm
Now we know why USAF wants RAPTOR based S2. 


Given these new numbers, with a heavier higher energy Raptor S2, F9 could probably cover the entire range of AtlasV/ D-IVH and still do RTLS for S1.  Many flight profiles could potentially recover the Raptor based S2 as well.


Talk about game changing economics!  :o


Add Raptor S2 to F9H and throw mass to Mars Even with 3 core RTLS would still be a very very large number.


These new numbers are STUNNING
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 04/30/2016 06:37 pm
How can the Falcon 9 numbers keep increasing (by more than 100% at this point) but FH numbers have stayed the same since 2011?

The real question is, "How can the Falcon 9 numbers keep increasing while the price stays the same?"
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: M_Puckett on 04/30/2016 06:48 pm
The SpaceX FH web page has been updated with new performance values:
http://www.spacex.com/falcon-heavy (http://www.spacex.com/falcon-heavy)

13,600 kg to Mars
22,200 kg to GTO
54,400 kg to LEO

Just missing the Moon value. Should be somewhere between the Mars and GTO and higher than the earlier 18,000 kg value for 1.1 since these are > than those for Mars and GTO.

2,900 kg to Pluto

Looks like SpaceX is now soliciting for beyond-Mars missions as well...

2,900KG to Pluto?  That's no Mickey Mouse Booster!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: alang on 04/30/2016 06:52 pm
During the raptor upper stage speculation has there been any discussion as to whether it would still be worth doing if sub-optimal. I.e. without a full size expansion nozzle.
The point of this would be to maintain engine commonality with the raptor being used on the BFS but not having to have a very wide upper stage on the Falcon Heavy with its associated costs.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mme on 04/30/2016 06:59 pm
How can the Falcon 9 numbers keep increasing (by more than 100% at this point) but FH numbers have stayed the same since 2011?
Probably because FH not flown yet.  They consistently sand bagged the F9, I imagine they'll do the same with the FH.  I also think they may be reluctant to expend the FH cores.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: joek on 04/30/2016 07:01 pm
The pricing/capabilities page also lists F9 as 28,800kg to LEO.
This is inconsistent with FH at 54,400... so, one number is wrong or they are comparing apples to oranges.
13,150kg; 28,991lb.
edit: but I see where the confusion is coming from... looks like a copy-paste error by someone at SpaceX.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: inonepiece on 04/30/2016 09:32 pm
Is there a FH update thread somewhere?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Endeavour_01 on 04/30/2016 11:03 pm
My guess is the 54 tonnes is disposable with cross-feed. I want to know what she will do with Raptor-US.

And the tables are copied from old graphics without being updated.

That would be my guess as well. It makes the most sense given the information we have.

Probably because FH not flown yet.  They consistently sand bagged the F9, I imagine they'll do the same with the FH.  I also think they may be reluctant to expend the FH cores.

Is there any evidence that SpaceX intentionally mislead people about the F9 performance numbers? Why would they do that? There is no reason to do so.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: S.Paulissen on 04/30/2016 11:33 pm
My guess is the 54 tonnes is disposable with cross-feed. I want to know what she will do with Raptor-US.

And the tables are copied from old graphics without being updated.

That would be my guess as well. It makes the most sense given the information we have.

Probably because FH not flown yet.  They consistently sand bagged the F9, I imagine they'll do the same with the FH.  I also think they may be reluctant to expend the FH cores.

Is there any evidence that SpaceX intentionally mislead people about the F9 performance numbers? Why would they do that? There is no reason to do so.

There's a saying that goes "Never attribute to malice what could instead be attributed to ignorance."

I think that applies here in the form of a webmaster inputting data into the html and typed the liftoff thrust of 8300 (kN), twice into the GTO payload which should probably read 5300 (kg) instead of 8300 (kg).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Johnnyhinbos on 04/30/2016 11:46 pm
I've no idea where to post this, but Elon just tweet confirmed the updated capabilities of both F9 and FH...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 04/30/2016 11:54 pm
Well there it is.  Hard to claim a clerical error now.

Very impressive.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Johnnyhinbos on 04/30/2016 11:55 pm
Follow on...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 04/30/2016 11:55 pm

Is there any evidence that SpaceX intentionally mislead people about the F9 performance numbers? Why would they do that? There is no reason to do so.

They have not mislead people, they've just been giving conservative estimates as they optimise their LV for higher and higher performance ratios. In addition, some of those older figures were for reuse figures - now they're giving the expendable figure for F9 and (I think, unless Musk's tweets contradict me) the partial reuse figure for FH. Understanding those figures takes some kremlinology, to be sure, but it's more a case of "playing it safe".

It's probably a result of the test-as-you-fly ethos. To reduce the chance of overstraining your architecture, fly your architecture conservatively, then build up. Push harder here, run a turbopump harder there, and don't over promise until you've got as much data as you possibly can. Then, once you have that data, optimise. Set the benchmark higher then repeat.

At this point, merlin is probably running as hard as they can make it run.

Edit: Of course, they might update it again - but it's already a shatteringly good kerolox engine that can compete with engines running significantly more efficient fuel types. It's already the Omega engine for what they need right now. Repeating the same process with raptor probably makes more sense at this point.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sewebster on 05/01/2016 12:02 am
Luke ‏@lukealization  4 minutes ago
@elonmusk Does FH expendable performance include crossfeed? Crossfeed is generally off the table correct? Rather difficult to implement...

Elon Musk ‏@elonmusk  37 seconds ago
@lukealization No cross feed. It would help performance, but is not needed for these numbers.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Rebel44 on 05/01/2016 12:03 am
Some important tweets:

Quote
@elonmusk wrote: Just posted latest max payload capabilities of Falcon 9 and Heavy https://t.co/Z45Y5V7G91

Quote
@mattyteare Basically current, but higher throttle setting. Good performance of recent launches allows us to reduce 3 sigma reserve margin. http://twitter.com/statuses/726559284306173952

Quote
@elonmusk Max performance numbers are for expendable launches. Subtract 30% to 40% for reusable booster payload. http://twitter.com/statuses/726559990480150528

Quote
@lukealization No physical changes to the engine. This thrust increase is based on delta qual tests. It is just tougher than we thought. http://twitter.com/statuses/726560848177561600

Quote
@lukealization No cross feed. It would help performance, but is not needed for these numbers. http://twitter.com/statuses/726561442636263425
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mongo62 on 05/01/2016 12:05 am
So WITH cross-feed, FH would probably beat SLS Block I in payload to LEO?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 05/01/2016 12:05 am
Good Lord....eye watering for no crossfeed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 05/01/2016 12:15 am
So WITH cross-feed, FH would probably beat SLS Block I in payload to LEO?

No idea. But imagine what it's going to do with raptor upper stage.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/01/2016 12:16 am
How can the Falcon 9 numbers keep increasing (by more than 100% at this point) but FH numbers have stayed the same since 2011?
Probably because FH not flown yet.  They consistently sand bagged the F9, I imagine they'll do the same with the FH.  I also think they may be reluctant to expend the FH cores.

Bingo!!

With the manifest that SpaceX has, the  number of launch pads to keep busy, they need a fleet of boosters.

I believe the sandbagging is reasonable conservative engineering, but also, leaving themselves margin for recovery.

Regarding engine thrust, the center with 1,845,000 LBf and after the side boosters detach is really going to pull some G's
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sewebster on 05/01/2016 12:19 am
So WITH cross-feed, FH would probably beat SLS Block I in payload to LEO?

Maybe SLS is sandbagged.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/01/2016 12:23 am
Good Lord....eye watering for no crossfeed.

That's why it's on the back burner.  There are no payloads that need it right now.  If one came up they could probably develop and deploy it in the length of time needed to meet the launch.   

Payloads that size wouldn't just pop up in a few months.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 05/01/2016 12:23 am
So WITH cross-feed, FH would probably beat SLS Block I in payload to LEO?

No idea. But imagine what it's going to do with raptor upper stage.
Crossfeed was to add 20-30% performance increase or for this incantation would result in a 65-70mt performance.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 05/01/2016 12:28 am


Payloads that size wouldn't just pop up in a few months.

Agreed - the most enabling expansion to FH they could do right now would be to develop that longer fairing. They're not mass limited in any regard, they're fairing limited.

Actually, come to think of it, "size" is more of a problem than mass right now.

So WITH cross-feed, FH would probably beat SLS Block I in payload to LEO?

No idea. But imagine what it's going to do with raptor upper stage.
Crossfeed was to add 20-30% performance increase or for this incantation would result in a 65-70mt performance.

Blimmin' 'eck.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mme on 05/01/2016 12:29 am
...
Probably because FH not flown yet.  They consistently sand bagged the F9, I imagine they'll do the same with the FH.  I also think they may be reluctant to expend the FH cores.

Is there any evidence that SpaceX intentionally mislead people about the F9 performance numbers? Why would they do that? There is no reason to do so.
I don't see it as misleading.  I see it as conservative, allowing initial missions to be well within the capabilities.  Raise the numbers as you get confidence based on flight experience.  But that was a total shot in the dark with regard to FH numbers.  I'm probably wrong, but did not intend to imply any sort of misinformation campaign.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 05/01/2016 12:36 am
As far payloads that would use crossfeed can you say a BA2100?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Nomadd on 05/01/2016 12:39 am
 I'm a little lost. Falcon 9 at 5.5T GTO and Falcon Heavy at 6.4T GTO doesn't seem to make a lot of sense. Even if the F9 was expendable and FH was 3 cores RTLS, almost half again the cost and three times as much vehicle for a 16% increase in payload doesn't seem like a great selling point. There's way too much missing out of those figures.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: kch on 05/01/2016 12:40 am
So WITH cross-feed, FH would probably beat SLS Block I in payload to LEO?

Maybe SLS is sandbagged.

It might be -- we'll know soon enough.  :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 05/01/2016 12:42 am
I'm a little lost. Falcon 9 at 5.5T GTO and Falcon Heavy at 6.4T GTO doesn't seem to make a lot of sense. Even if the F9 was expendable and FH was 3 cores RTLS, almost half again the cost and three times as much vehicle for a 16% increase in payload doesn't seem like a great selling point. There's way too much missing out of those figures.
I believe not all the values have been changed on the pages. The 6.4T value is a small print value under the price value. Both may change in the near future.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 05/01/2016 12:47 am
Regarding people not believing these numbers:

Falcon 9/H upper stage is supposed to have an full:empty mass ratio of 107:4 (the 4 tons dry is estimated, that's aggressive but it could be even less). Isp is 348s for Merlin 1D Vac (impressive).
https://www.google.com/?#q=348*9.80665*ln(107/4) (https://www.google.com/?#q=348*9.80665*ln(107/4)) = 11.2km/s
vs the D4H upper stage, which has much worse Isp:
https://www.google.com/?#q=462*9.80665*ln((30710)/(3490) (https://www.google.com/?#q=462*9.80665*ln((30710)/(3490)) = 9.85km/s.

(in both cases, that's for no payload, just the stage)

And realize that the SpaceX upper stage will have a much higher thrust/weight ratio over the length of the burn, so lower gravity losses (and/or a better Oberth effect).

Isp isn't everything.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: bunker9603 on 05/01/2016 12:54 am
I'm a little lost. Falcon 9 at 5.5T GTO and Falcon Heavy at 6.4T GTO doesn't seem to make a lot of sense. Even if the F9 was expendable and FH was 3 cores RTLS, almost half again the cost and three times as much vehicle for a 16% increase in payload doesn't seem like a great selling point. There's way too much missing out of those figures.
I believe not all the values have been changed on the pages. The 6.4T value is a small print value under the price value. Both may change in the near future.


I think you are right and I wouldn't be suprised if the FH numbers change after they get several launches under their belt.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 05/01/2016 01:15 am
I'm a little lost. Falcon 9 at 5.5T GTO and Falcon Heavy at 6.4T GTO doesn't seem to make a lot of sense. Even if the F9 was expendable and FH was 3 cores RTLS, almost half again the cost and three times as much vehicle for a 16% increase in payload doesn't seem like a great selling point. There's way too much missing out of those figures.
Now updated to 8mt for FH
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 05/01/2016 01:18 am
I'm a little lost. Falcon 9 at 5.5T GTO and Falcon Heavy at 6.4T GTO doesn't seem to make a lot of sense. Even if the F9 was expendable and FH was 3 cores RTLS, almost half again the cost and three times as much vehicle for a 16% increase in payload doesn't seem like a great selling point. There's way too much missing out of those figures.
Now updated to 8mt for FH
The implication is that these are both the figures if you have a trajectory that allows booster recovery, along with some margin. For Falcon 9, probably a barging. For Falcon Heavy, probably RTLS landing for all the cores, given how much lower it is than the 22 tons GTO for expendable.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 05/01/2016 01:22 am
And the 28.8 mt for F9 were wrong, too, it's only 22.8mt
https://twitter.com/elonmusk/status/726579536410734592
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mme on 05/01/2016 01:25 am
I'm a little lost. Falcon 9 at 5.5T GTO and Falcon Heavy at 6.4T GTO doesn't seem to make a lot of sense. Even if the F9 was expendable and FH was 3 cores RTLS, almost half again the cost and three times as much vehicle for a 16% increase in payload doesn't seem like a great selling point. There's way too much missing out of those figures.
Now updated to 8mt for FH
Now if we could just get clarification on 5.5 mT/8.0 mT vs (8300 kg/22200 kg).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 05/01/2016 01:27 am
So WITH cross-feed, FH would probably beat SLS Block I in payload to LEO?

Maybe SLS is sandbagged.

It might be -- we'll know soon enough.  :)

Now I really want to know what disposable with cross-feed and Raptor US will do. Could it be in the 70s, 80s even? Getting those numbers published between the election and the inauguration could induce a new administration to demand SLS/Orion cancellation and instruct NASA to cooperate with SX through SAAs.

I know this isn't the space policy section, but these performance numbers coupled with the astronomical difference in price and the MCT reveal could be the impetus that results in that change. If we have a new president who wins in a landslide, he/she could claim a mandate for change. With SX free to control the direction and pace of their architecture but NASA at their disposal to assist and buy missions.......well.........I think it could be a good synergy. I hope they announce those numbers with or before the September reveal.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: pippin on 05/01/2016 01:27 am
Well, since they just changed the 6.4mt to 8.0mt I'd consider at least that figure to be correct. If it's not then the whole page would be pretty useless as a source.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 05/01/2016 02:12 am
Regarding people not believing these numbers:

Falcon 9/H upper stage is supposed to have an full:empty mass ratio of 107:4 (the 4 tons dry is estimated, that's aggressive but it could be even less). Isp is 348s for Merlin 1D Vac (impressive).
https://www.google.com/?#q=348*9.80665*ln(107/4) (https://www.google.com/?#q=348*9.80665*ln(107/4)) = 11.2km/s
vs the D4H upper stage, which has much worse Isp:
https://www.google.com/?#q=462*9.80665*ln((30710)/(3490) (https://www.google.com/?#q=462*9.80665*ln((30710)/(3490)) = 9.85km/s.

(in both cases, that's for no payload, just the stage)

And realize that the SpaceX upper stage will have a much higher thrust/weight ratio over the length of the burn, so lower gravity losses (and/or a better Oberth effect).

Isp isn't everything.

Yep. And you have to chuckle when you read some other posters in the "Isp is everything brigade" recently post on another thread that SpaceX couldn't  do much worse than the current upper stage. :D
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Billium on 05/01/2016 02:13 am
So if FH gets 22,200kg to GTO, and 13,600kg to Mars, does anyone have a semi approximate number for Trans-Lunar injection?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LM13 on 05/01/2016 02:18 am
So if FH gets 22,200kg to GTO, and 13,600kg to Mars, does anyone have a semi approximate number for Trans-Lunar injection?

Back-of-the-envelope Rocket Equation, assuming 60.4 tonnes IMLEO (including second stage) and a TLI delta-V of 3.25 km/s, gives 16.7 tonnes of payload through TLI (22.7 including second stage). 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 05/01/2016 02:37 am
http://www.spacex.com/falcon-heavy (http://www.spacex.com/falcon-heavy)
54,400 kg to LEO

[buff fingernails against lapel]And presumably without cross feed ... http://forum.nasaspaceflight.com/index.php?topic=39181.msg1521480#msg1521480 (http://forum.nasaspaceflight.com/index.php?topic=39181.msg1521480#msg1521480) [/buff fingernails against lapel]
Disagree, the quoted website says
Quote
For missions involving exceptionally heavy payloads—greater than 45,000 kilograms or 100,000 pounds—Falcon Heavy offers a unique cross-feed propellant system.
And 54,400 is more than 45,000. I therefore suppose that the other maxima also are with crossfeed. Furthermore Gwynne Shotwell has said that crossfeed is not yet developed, but may be if there is demand for it, so the numbers on this page are quite theoretical.

No, see this:

Luke ‏@lukealization  4 minutes ago
@elonmusk Does FH expendable performance include crossfeed? Crossfeed is generally off the table correct? Rather difficult to implement...

Elon Musk ‏@elonmusk  37 seconds ago
@lukealization No cross feed. It would help performance, but is not needed for these numbers.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: 2552 on 05/01/2016 03:19 am
Also, the section on crossfeed has been removed from the Falcon Heavy page (http://www.spacex.com/falcon-heavy).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MATTBLAK on 05/01/2016 03:27 am
It was only recently I was saying that crossfeed was unlikely to be a priority for Space X - and I was scorned for saying so! ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: miki on 05/01/2016 09:28 am
With these new numbers for Heavy, a few questions come to mind.
* What would FH payload be to Jupiter/Europa? Could it replace SLS as launch rocket for Europa mission curently in development?
* With 2,9t to Pluto, is Pluto orbiter possible (I know it is off topic, but new FH numbers are just awesome)? New Horizons is less than 500kg. So with added fuel tanks there would be alsmost or over 2t of fuel for orbit insertion?
* As per earlier comments, I wander how much can SpaceX extend current diameter payload fairing? I guess missions woth two satelites on FH to GTO are not considered because of the costs?
* And last but not least, a fully expendable FH with maximum payload would cost around...? Much less than Delta 4H I guess? :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Rebel44 on 05/01/2016 02:57 pm
any info, about increased thrust of second stage, or increased isp?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/01/2016 04:30 pm
With these new numbers for Heavy, a few questions come to mind.
<snip>
* And last but not least, a fully expendable FH with maximum payload would cost around...? Much less than Delta 4H I guess? :)

The webpage formerly showed $135M for FH... since other bottom line prices remained stable with the latest increases in payload, probably can use that number as an estimate.  Webpage also advertises FH as one third the DH price, so around $400M.  ULA is saying DH is heading for $1B with retirement of DIVM in near future; I cannot locate the reference, but innumerable statements to the effect that Delta is not cost competitive with Falcon.

So yes, much less.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/01/2016 05:58 pm
With these new numbers for Heavy, a few questions come to mind.
<snip>
* And last but not least, a fully expendable FH with maximum payload would cost around...? Much less than Delta 4H I guess? :)

The webpage formerly showed $135M for FH... since other bottom line prices remained stable with the latest increases in payload, probably can use that number as an estimate.  Webpage also advertises FH as one third the DH price, so around $400M.  ULA is saying DH is heading for $1B with retirement of DIVM in near future; I cannot locate the reference, but innumerable statements to the effect that Delta is not cost competitive with Falcon.

So yes, much less.

$1,000,000,000 per DIVH launch?

Oh my 😳
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 05/01/2016 06:10 pm
convince science projects to build multiple copies of their payload and all of a sudden two copies and two launches if the first one doesn't work is still way less than DIVH... that cuts into assurance claims as motivators, ULA needs Vulcan to stay competitive. Right now, they're OK since FH hasn't launched but they can't count on that staying that way for long.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: alang on 05/01/2016 10:35 pm
convince science projects to build multiple copies of their payload and all of a sudden two copies and two launches if the first one doesn't work is still way less than DIVH... that cuts into assurance claims as motivators, ULA needs Vulcan to stay competitive. Right now, they're OK since FH hasn't launched but they can't count on that staying that way for long.

If dragon launch escape * to orbit can be shown to work reliably then that could also start to change these kind of calculations.

*edit launch escape not abort
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 05/01/2016 11:58 pm
This is not an SLS thread. Trimmed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: kch on 05/02/2016 12:19 am
With these new numbers for Heavy, a few questions come to mind.
<snip>
* And last but not least, a fully expendable FH with maximum payload would cost around...? Much less than Delta 4H I guess? :)

The webpage formerly showed $135M for FH... since other bottom line prices remained stable with the latest increases in payload, probably can use that number as an estimate.  Webpage also advertises FH as one third the DH price, so around $400M.  ULA is saying DH is heading for $1B with retirement of DIVM in near future; I cannot locate the reference, but innumerable statements to the effect that Delta is not cost competitive with Falcon.

So yes, much less.

$1,000,000,000 per DIVH launch?

Oh my 😳

If true, that might explain why they're retiring DIVM.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: QuantumG on 05/02/2016 05:26 am
How do you even make a rocket that expensive?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: llanitedave on 05/02/2016 05:39 am
How do you even make a rocket that expensive?


Practice, practice, practice!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Nilof on 05/02/2016 11:42 am
How do you even make a rocket that expensive?

By not having any launches on manifest for your rocket, but still supporting the fixed costs because that one loaded customer is willing to pay for it. Sort of like Titan IV, except Atlas V wasn't around as a workhorse launcher back then and there were more Titan-only payloads.

Still, it's interesting to see how it manages to be about as expensive per launch as the inflation-adjusted Saturn V. That tends to support the assertion that flight rate is indeed everything.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 05/02/2016 01:16 pm
How do you even make a rocket that expensive?
I've half a mind that it wouldn't really be that expensive, and this is posturing from ULA... you could have flown the Shuttle twice for that expense.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Nilof on 05/02/2016 02:05 pm
How do you even make a rocket that expensive?
I've half a mind that it wouldn't really be that expensive, and this is posturing from ULA... you could have flown the Shuttle twice for that expense.

The shuttle flew four times a year. The Delta IV heavy flies once every two years. The marginal cost of flying a D4H is likely not even close to 1B, but the cost of maintaining the entire Delta infrastructure for launches this infrequent certainly could add up to that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: M_Puckett on 05/02/2016 02:20 pm
With these new numbers for Heavy, a few questions come to mind.
<snip>
* And last but not least, a fully expendable FH with maximum payload would cost around...? Much less than Delta 4H I guess? :)

The webpage formerly showed $135M for FH... since other bottom line prices remained stable with the latest increases in payload, probably can use that number as an estimate.  Webpage also advertises FH as one third the DH price, so around $400M.  ULA is saying DH is heading for $1B with retirement of DIVM in near future; I cannot locate the reference, but innumerable statements to the effect that Delta is not cost competitive with Falcon.

So yes, much less.

$1,000,000,000 per DIVH launch?

Oh my 😳

If true, that might explain why they're retiring DIVM.

Retiring the Delta IV Medium is likely responsible for that one Billion Dollar number for the heavy.  It has to bear ALL of the fixed costs.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: alang on 05/02/2016 04:02 pm
Slightly OT but no more so than the Delta IV:
If the Falcon Heavy demo involved boosting a dragon on a lunar free return orbit, could useful course corrections be done without super Dracos? Are there any published figures for the ordinary Dracos' abilities? SpaceX seem happy to publish their launchers' abilities.

Edit: the wiki article says 18 thrusters of 400 Newtons but nothing about how much stored propellant/seconds of operation.
Edit 2: wiki says the Apollo service module had an oversized 91KN engine. It also talks about hypergolic propellant being stored in two 40cm diameter tanks. I make that roughly 35 litres each. Which doesn't sound like much.
An online log of Apollo 11 talks of a 3 second course correction burn.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 05/02/2016 04:59 pm
The shuttle flew four times a year. The Delta IV heavy flies once every two years. The marginal cost of flying a D4H is likely not even close to 1B, but the cost of maintaining the entire Delta infrastructure for launches this infrequent certainly could add up to that.
When you consider the enormous size of the Shuttle infrastructure and workforce, I still don't think it adds up.  I certainly can't back that up with data, of course, so I will leave it at that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 05/03/2016 12:02 am
Slightly OT but no more so than the Delta IV:
If the Falcon Heavy demo involved boosting a dragon on a lunar free return orbit, could useful course corrections be done without super Dracos? Are there any published figures for the ordinary Dracos' abilities? SpaceX seem happy to publish their launchers' abilities.

Cargo Dragon does all orbit changes with Draco. Course corrections on a free return trajectory must be much smaller than that.

Edit typo
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 05/03/2016 12:57 am
Superdracos are not useful for anything but abort and landing. Isp is too low and thrust is too high plus you have those big cosine losses. Just use the regular Dracos, they're quite efficient.

Why does this come up so often?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dorkmo on 05/03/2016 01:05 am
Superdracos are not useful for anything but abort and landing. Isp is too low and thrust is too high plus you have those big cosine losses. Just use the regular Dracos, they're quite efficient.

Why does this come up so often?

because we all watched tim the tool man. and he'd use the super dracos for all manuvers.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rocx on 05/03/2016 07:10 am
Slightly OT but no more so than the Delta IV:
If the Falcon Heavy demo involved boosting a dragon on a lunar free return orbit, could useful course corrections be done without super Dracos? Are there any published figures for the ordinary Dracos' abilities? SpaceX seem happy to publish their launchers' abilities.

Edit: the wiki article says 18 thrusters of 400 Newtons but nothing about how much stored propellant/seconds of operation.
Edit 2: wiki says the Apollo service module had an oversized 91KN engine. It also talks about hypergolic propellant being stored in two 40cm diameter tanks. I make that roughly 35 litres each. Which doesn't sound like much.
An online log of Apollo 11 talks of a 3 second course correction burn.

Draco and SuperDraco use the same type of fuel, and I think but I'm not certain they draw from the same propellant tanks. So the best thruster to use in deep space would be the one with higher Isp (SuperDraco has 235s, don't know how much Draco has), and lower thrust for more precision.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: darkenfast on 05/04/2016 07:31 am
Slightly OT but no more so than the Delta IV:
If the Falcon Heavy demo involved boosting a dragon on a lunar free return orbit, could useful course corrections be done without super Dracos? Are there any published figures for the ordinary Dracos' abilities? SpaceX seem happy to publish their launchers' abilities.

Edit: the wiki article says 18 thrusters of 400 Newtons but nothing about how much stored propellant/seconds of operation.
Edit 2: wiki says the Apollo service module had an oversized 91KN engine. It also talks about hypergolic propellant being stored in two 40cm diameter tanks. I make that roughly 35 litres each. Which doesn't sound like much.
An online log of Apollo 11 talks of a 3 second course correction burn.

I believe the Apollo tanks were cylindrical with hemispherical end caps.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 05/04/2016 02:01 pm
Could the Super Dracos on Dragon II be used to slow down before hitting earths atmosphere on a free return from the moon thus not needing a heavier heat shield and just use parachutes and land in the ocean? 

Also, could they use previously flown Falcon 9's to assemble a Falcon Heavy demo flight?  This would save money since these cores were already paid for?  Just refurbishment and refueling costs.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Navier–Stokes on 05/04/2016 02:22 pm
Here's an article from SpaceFlight Now regarding possibility of a commercial payload during the first demonstration flight:

http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/ (http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/)

Quote
“There have been a number of customers interested in flying on that (mission),” Shotwell said in an interview with Spaceflight Now. “We’re trying to balance, does it make sense for this to just be our mission, so we own it completely?”

Quote
She said SpaceX will make the first Falcon Heavy launch “useful” by proving its capabilities to future customers, such as heaving a hefty payload to geostationary transfer orbit, the targeted drop-off orbit for communications satellites heading for stations 22,300 miles (nearly 36,000 kilometers) over the equator.

“Regardless of whether we fly a customer or a purely demonstration mission, we’ll make that mission useful, whether it’s to demonstrate something for a GTO (geostationary transfer orbit) capability for our commercial customers, or whether it’s to demonstrate some requirement for national security space,” Shotwell said.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Moderas on 05/04/2016 02:28 pm
Also, could they use previously flown Falcon 9's to assemble a Falcon Heavy demo flight?  This would save money since these cores were already paid for?  Just refurbishment and refueling costs.

There are some small tweaks between a F9 core and a FH side booster, but a F9 could be adapted to a side booster. The core on the other hand has some significant differences because it needs to handle additional forces on either side and increased loads on top from the heavier payload. It likely will not be worth it to convert an F9 core to a FH center booster.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Johnnyhinbos on 05/04/2016 02:30 pm


Draco and SuperDraco use the same type of fuel, and I think but I'm not certain they draw from the same propellant tanks. So the best thruster to use in deep space would be the one with higher Isp (SuperDraco has 235s, don't know how much Draco has), and lower thrust for more precision.

Yes, I was trying to figure out if the regular Dracos or the SuperDracos were being used in the GoPro footage of the D2 test flight...

http://youtu.be/WYSupJ5r2zo
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 05/04/2016 02:35 pm
Also, could they use previously flown Falcon 9's to assemble a Falcon Heavy demo flight?  This would save money since these cores were already paid for?  Just refurbishment and refueling costs.

There are some small tweaks between a F9 core and a FH side booster, but a F9 could be adapted to a side booster. The core on the other hand has some significant differences because it needs to handle additional forces on either side and increased loads on top from the heavier payload. It likely will not be worth it to convert an F9 core to a FH center booster.

Welcome, and congratulations on your first post!

Another perspective to keep in mind is that FH boosters should always be able to be recovered on land, so they should have a high recoverability rate.  If so, then for customer launches they really only need two boosters to cover their needs, or maybe four to keep spares around in case of unexpected loss or end of life issues.

So I'm not sure what the scenario would be that would require them to rework a stage instead of just building a new replacement.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Meltro on 05/04/2016 02:52 pm
Could the Super Dracos on Dragon II be used to slow down before hitting earths atmosphere on a free return from the moon thus not needing a heavier heat shield and just use parachutes and land in the ocean? 

No. Consider that if you were traveling below, say, mach 5, you would not need a heat shield (this is extremely optimistic, and stretches the definition of 'heat shield'). Low earth orbit starts at a little over mach 22, coming back from trans-lunar injection would be worse. There simply isn't enough fuel to do the job by several orders at least an order of magnitude.

What you are asking for is essentially the reverse of launching the spacecraft. A good explanation of why what you are asking is impractical can be found here https://what-if.xkcd.com/58/

edit: fixed some slight hyperbole
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 05/04/2016 03:04 pm
I know there are what 8 Super Draco's on a Dragon II spacecraft.  What if they only fired 4 to slow down from 25,000 mph coming from the moon to 17,000 mph normal orbital velocity to get into say an orbit, then fired them to come in at the normal orbital speed.  There wouldn't be enough fuel for landing with Dracos but with parachutes like Apollo.  If they are going to carry the SD's for LEM purposes and never needed.  That stored fuel could be used to slow down at least to orbital speed before coming home. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: philw1776 on 05/04/2016 03:09 pm
I know there are what 8 Super Draco's on a Dragon II spacecraft.  What if they only fired 4 to slow down from 25,000 mph coming from the moon to 17,000 mph normal orbital velocity to get into say an orbit, then fired them to come in at the normal orbital speed.  There wouldn't be enough fuel for landing with Dracos but with parachutes like Apollo.  If they are going to carry the SD's for LEM purposes and never needed.  That stored fuel could be used to slow down at least to orbital speed before coming home.

Run the numbers.  The delta V for the Dragon 2 with SuperDracos is hundreds of meters/sec, not THOUSANDS.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: ugordan on 05/04/2016 03:09 pm
I know there are what 8 Super Draco's on a Dragon II spacecraft.  What if they only fired 4 to slow down from 25,000 mph coming from the moon to 17,000 mph normal orbital velocity to get into say an orbit, then fired them to come in at the normal orbital speed. 

And where does propellant for all this come from?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Meltro on 05/04/2016 03:13 pm
I know there are what 8 Super Draco's on a Dragon II spacecraft.  What if they only fired 4 to slow down from 25,000 mph coming from the moon to 17,000 mph normal orbital velocity to get into say an orbit, then fired them to come in at the normal orbital speed.  There wouldn't be enough fuel for landing with Dracos but with parachutes like Apollo.  If they are going to carry the SD's for LEM purposes and never needed.  That stored fuel could be used to slow down at least to orbital speed before coming home. 

What would you accomplish? The heat shield is still needed, aerobraking is free delta-v. And you're still taking ~3.5 km/s d/v, which would require the spacecraft to expend about three times its weight mass in fuel to achieve.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: whitelancer64 on 05/04/2016 03:13 pm
I know there are what 8 Super Draco's on a Dragon II spacecraft.  What if they only fired 4 to slow down from 25,000 mph coming from the moon to 17,000 mph normal orbital velocity to get into say an orbit, then fired them to come in at the normal orbital speed.  There wouldn't be enough fuel for landing with Dracos but with parachutes like Apollo.  If they are going to carry the SD's for LEM purposes and never needed.  That stored fuel could be used to slow down at least to orbital speed before coming home.
There isn't enough fuel in the Dragon to slow down that much. It's far simpler and takes up much less weight just to thicken the heat shield enough to handle the higher re-entry velocity.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RonM on 05/04/2016 03:17 pm
I know there are what 8 Super Draco's on a Dragon II spacecraft.  What if they only fired 4 to slow down from 25,000 mph coming from the moon to 17,000 mph normal orbital velocity to get into say an orbit, then fired them to come in at the normal orbital speed.  There wouldn't be enough fuel for landing with Dracos but with parachutes like Apollo.  If they are going to carry the SD's for LEM purposes and never needed.  That stored fuel could be used to slow down at least to orbital speed before coming home.

I'm pretty sure Dragon 2 doesn't have anywhere near enough deltaV to slow down like you suggest (does anyone know the actual number). It's simpler and cheaper to use the heat shield.

Edit: Wow, something messed up and didn't tell me four people posted before I did. Usually, you get a warning about new posts.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 05/04/2016 03:37 pm
D2 reentry discussion may not be quite on topic for a FH thread. But maybe that's just me.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/04/2016 03:45 pm
Here's an article from SpaceFlight Now regarding possibility of a commercial payload during the first demonstration flight:

http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/ (http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/)

I was excited to read that story this morning.  We're only 6 months from so things should start happening very soon.

One thought I had reading the story is that if there is a payload that it will be announced rather soon. 

Very exciting times, looking forward to the first FH launch is an understatement.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: BrianNH on 05/04/2016 04:35 pm
Here's an article from SpaceFlight Now regarding possibility of a commercial payload during the first demonstration flight:

http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/ (http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/)

Here is another interesting bit of news from that article.

Quote
Shotwell said one of the booster cores destined to fly on the first Falcon Heavy launch is already under construction at SpaceX’s headquarters in Hawthorne, California.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Meltro on 05/04/2016 05:04 pm
Here's an article from SpaceFlight Now regarding possibility of a commercial payload during the first demonstration flight:

http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/ (http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/)

I find this to be a most exciting development. I wish I knew more about exactly what the launch market was like. I could guess that some providers see the potential opportunity to reach market with their services 2-3 years ahead of schedule (who has hardware ready to fly, though?) as outweighing the risks of a vehicle's first launch. I do wonder who, if anyone, would be willing to insure such a flight and at what cost relative to other vehicles?

Either way, I think it's fantastic that in about a decade, SpaceX has gone from "Well, I guess we have enough parts to put together a fourth try" to having customers bidding on the first flight of a hugely complex new design.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LastStarFighter on 05/04/2016 05:24 pm
Here's an article from SpaceFlight Now regarding possibility of a commercial payload during the first demonstration flight:

http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/ (http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/)

Here is another interesting bit of news from that article.

Quote
Shotwell said one of the booster cores destined to fly on the first Falcon Heavy launch is already under construction at SpaceX’s headquarters in Hawthorne, California.

I found it interesting that Shorwell eluded that full FH testing won't be done in Texas.

Quote
The launch preparations in Florida will culminate with a hold-down firing of all 27 first stage engines, the first time SpaceX will analyze how the engines operate in unison, according to Shotwell.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: tleski on 05/04/2016 05:49 pm
People were discussing this. The current guess is: they will test single sticks one after another in McGregor but the final integration and static fire of FH will happen in Florida. One of the reasons: no sign of triple core hold-down hardware at McGregor.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/04/2016 07:03 pm
People were discussing this. The current guess is: they will test single sticks one after another in McGregor but the final integration and static fire of FH will happen in Florida. One of the reasons: no sign of triple core hold-down hardware at McGregor.

There was no discussion on how long a burn at 39A will be.  I can see there being a longer, but not full duration, burn with some simulated inputs to verify control responses and center core throttling.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kaputnik on 05/04/2016 07:33 pm
I imagine that this must have been suggested and discussed before, but my google-fu is not strong enough to find any mention of it, so:

Seeing as FH has a launch T:W of about 1.6:1, would it not be advantageous to lose some engines off the centre core? If you dropped to e.g. five engines you may gain more performance through reduced mass than you lose in higher gravity losses. Then there is the saving of the cost of four engines, offset against the production issues of having 'different' cores (surely it is cheaper to build a core with five engines than nine though?).

As i say I assume this has been discussed before but I would be interested in seeing the outcome of that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: groundbound on 05/04/2016 07:34 pm
People were discussing this. The current guess is: they will test single sticks one after another in McGregor but the final integration and static fire of FH will happen in Florida. One of the reasons: no sign of triple core hold-down hardware at McGregor.

Spacex Kremlinology question: does this imply anything long term about how FH fits (or doesn't) into the current ecosystem of Hawthorne-build, Mcgregor-test, FL/Vandy-launch?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LastStarFighter on 05/04/2016 07:39 pm
People were discussing this. The current guess is: they will test single sticks one after another in McGregor but the final integration and static fire of FH will happen in Florida. One of the reasons: no sign of triple core hold-down hardware at McGregor.

Spacex Kremlinology question: does this imply anything long term about how FH fits (or doesn't) into the current ecosystem of Hawthorne-build, Mcgregor-test, FL/Vandy-launch?

My guess is that they are only doing this so the new vehicle test don't mess up the flow for actual missions. However maybe we will never see a full heavy test in McGregor. Who knows!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 05/04/2016 07:40 pm
I imagine that this must have been suggested and discussed before, but my google-fu is not strong enough to find any mention of it, so:

Seeing as FH has a launch T:W of about 1.6:1, would it not be advantageous to lose some engines off the centre core? If you dropped to e.g. five engines you may gain more performance through reduced mass than you lose in higher gravity losses. Then there is the saving of the cost of four engines, offset against the production issues of having 'different' cores (surely it is cheaper to build a core with five engines than nine though?).

As i say I assume this has been discussed before but I would be interested in seeing the outcome of that.

Given the recently announced thrust increases, it is possible that it is correct, but given the tremendous thrust to weight ratio, it may well be that the performance increase due to lower weight (most of which would be seen on the centre core operations after the side boosters separated) does not counter balance the benefit against gravity losses in the first few seconds of the flight when they are at their most extreme and the rocket is nearly vertical. Obviously very shortly into the flight you start shutting down, then throttling down the centre core engines, but the extra performance at takeoff is probably quite significant.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LastStarFighter on 05/04/2016 07:43 pm
People were discussing this. The current guess is: they will test single sticks one after another in McGregor but the final integration and static fire of FH will happen in Florida. One of the reasons: no sign of triple core hold-down hardware at McGregor.

Spacex Kremlinology question: does this imply anything long term about how FH fits (or doesn't) into the current ecosystem of Hawthorne-build, Mcgregor-test, FL/Vandy-launch?

And aren't they building a second single core first stage test stand at McGregor? About a mile due east.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Arb on 05/04/2016 07:56 pm
We were told that the partially built test stand had been abandoned, for now.

Also, that the reason to not test a triple core at McGregor is that it would have to be disassembled for transportation then reassembled and retested at the launch site.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Meltro on 05/04/2016 07:59 pm
I imagine that this must have been suggested and discussed before, but my google-fu is not strong enough to find any mention of it, so:

Seeing as FH has a launch T:W of about 1.6:1, would it not be advantageous to lose some engines off the centre core? If you dropped to e.g. five engines you may gain more performance through reduced mass than you lose in higher gravity losses. Then there is the saving of the cost of four engines, offset against the production issues of having 'different' cores (surely it is cheaper to build a core with five engines than nine though?).

As i say I assume this has been discussed before but I would be interested in seeing the outcome of that.

You'd be hurting at liftoff, as nadreck said. That's where your T:W is going to be at it's lowest, and you want to get as much acceleration as possible early on. At some point there will be throttling back yes, but those precious early seconds where your acceleration vector is opposite gravity are where you make a LOT of your money.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kaputnik on 05/04/2016 08:05 pm
Yes but with a T:W of 1.6 FH isn't exactly clawing its way off the pad. Isn't Antares at something like 1.1?
I was hoping that somebody with a bit more knowledge and time than me had run the numbers on it as it is obviusly a tradeoff.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 05/04/2016 08:37 pm
Well to get a general sense of the numbers if you removed 5 engines from the centre core you would save about 2500kg (a little less really but lets round this one up).

Having 2500 less kg on the central core is not going to give you more than a 30m/s advantage on the central core in expendable mode, with the lightest payload and it drops a bit from there. If you are recovering to an ASDS it is less than 20m/s advantage. During the side core boost phase it would have a much smaller benefit because it is much smaller percentage of the total mass being accelerated, and the lack of 5 out of 27 engines would take you from 1.6 TW to 1.3  which means your initial vertical acceleration is HALF what it would be with all 27 engines. This would delay your start of gravity turn by at least half as long again as when it would have started otherwise and if you presume that the gravity [edit to insert]turn[/edit*] normally starts even 10 seconds into the flight, just in that first 15 seconds you lost something like .3*15*9.8 m/s  (44 m/s) you are still losing after the gravity turn starts, but that first 15 seconds was the worst and your thrust to weight ratio is starting to catch up with you again by then.

*you know it would be really awesome on all launchers if we could get the first 10 seconds of launch without gravity! Even better if the 2nd stage could get by without inertia for a little while!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Meltro on 05/04/2016 08:47 pm
Yes but with a T:W of 1.6 FH isn't exactly clawing its way off the pad. Isn't Antares at something like 1.1?
I was hoping that somebody with a bit more knowledge and time than me had run the numbers on it as it is obviusly a tradeoff.

Off the top of my head, would need individual weight of the Merlin engines, empty core weight, weight of fuel, an isp profile for the engines, drag coefficients for the individual boosters as well as the core and payload, structural integrity limits...I'd love an excuse to dust off my dynamics texts but I think we're too soft on a lot of these numbers to build a real meaningful answer. That isn't to say I couldn't plug in numbers, but small deviations in the above could generate radically different answers on whether or not an idea is feasible. You'd get an answer, but it would probably be meaningless.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 05/04/2016 09:02 pm


Off the top of my head, would need individual weight of the Merlin engines, empty core weight, weight of fuel, an isp profile for the engines, drag coefficients for the individual boosters as well as the core and payload, structural integrity limits...I'd love an excuse to dust off my dynamics texts but I think we're too soft on a lot of these numbers to build a real meaningful answer. That isn't to say I couldn't plug in numbers, but small deviations in the above could generate radically different answers on whether or not an idea is feasible. You'd get an answer, but it would probably be meaningless.

The numbers I use are

Merlin engines around 450kg
Empty core weight 25.6t with legs, 23.1t without
ISPSL 282
ISPVac 311

I ignore drag and structural limits, and in this problem solving instance I think it is irrelevant because you are reducing thrust and speed through the air
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Meltro on 05/04/2016 09:10 pm
Having 2500 less kg on the central core is not going to give you more than a 30m/s advantage on the central core in expendable mode, with the lightest payload and it drops a bit from there.

Is there a central thread somewhere for known figures on vehicle masses? I seem to have self nerd-sniped.

edit: thank you, now just need S2 weight. Might be crawling through wikipedia for a bit.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Meltro on 05/04/2016 09:17 pm
I ignore drag and structural limits, and in this problem solving instance I think it is irrelevant because you are reducing thrust and speed through the air

True enough, was thinking more along the lines of a complete simulation. My only caveat would be the possibility of the falcon throttling down around max-q due to structural limits, which would favor the reduced-engine profile slightly. If it never throttles down, I would agree with you 100%.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 05/04/2016 09:25 pm
I ignore drag and structural limits, and in this problem solving instance I think it is irrelevant because you are reducing thrust and speed through the air

True enough, was thinking more along the lines of a complete simulation. My only caveat would be the possibility of the falcon throttling down around max-q due to structural limits, which would favor the reduced-engine profile slightly. If it never throttles down, I would agree with you 100%.

Actually on my FH spreadsheet (http://forum.nasaspaceflight.com/index.php?topic=34077.msg1500227#msg1500227) (see the other posts that one links to)  I presume it throttles down 24 seconds in (actually not throttling down, but shutting down 2 of the 9 centre core engines to start fuel conservation, it is well below maxQ speeds at that point. Oh and for the record I don't presume the gravity turn starts until 26 seconds in.

Honestly I need to play with the assumptions for the initial boost phase given the latest thrust numbers, but I haven't yet.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 05/04/2016 09:37 pm
Having 2500 less kg on the central core is not going to give you more than a 30m/s advantage on the central core in expendable mode, with the lightest payload and it drops a bit from there.

Is there a central thread somewhere for known figures on vehicle masses? I seem to have self nerd-sniped.

edit: thank you, now just need S2 weight. Might be crawling through wikipedia for a bit.

Hmm it is often a matter of discussion, you can check out the previous Falcon Heavy thread http://forum.nasaspaceflight.com/index.php?topic=36806.msg1332177#msg1332177 (http://forum.nasaspaceflight.com/index.php?topic=36806.msg1332177#msg1332177)
and around when I put together the FH spreadsheet (then later updated it for Full Thrust) we certainly had some discussions around the numbers we should use. But no I don't know of anywhere authoritative and I just try my best with the numbers I can find out. I also have tried back engineering numbers, for example if you are confident in the estimates for the 2nd stage parameters, you can figure out the speed at which the stage had to have separated at to check the modelling of the booster core.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Meltro on 05/04/2016 09:44 pm

Actually on my FH spreadsheet (http://forum.nasaspaceflight.com/index.php?topic=34077.msg1500227#msg1500227) (see the other posts that one links to)  I presume it throttles down 24 seconds in (actually not throttling down, but shutting down 2 of the 9 centre core engines to start fuel conservation, it is well below maxQ speeds at that point. Oh and for the record I don't presume the gravity turn starts until 26 seconds in.

Honestly I need to play with the assumptions for the initial boost phase given the latest thrust numbers, but I haven't yet.

Yay, numbers! Thank you. I noticed you used the SL Isp down the line, is there any good way to refine that? I'm thinking linearization against atmospheric density but I don't know the specifics on how atmosphere/pressure/(velocity?) affect Isp.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: CraigLieb on 05/04/2016 09:49 pm
We were told that the partially built test stand had been abandoned, for now.

Also, that the reason to not test a triple core at McGregor is that it would have to be disassembled for transportation then reassembled and retested at the launch site.

Another consideration why they might be taking this approach
Waiting to gather all the stages at McGregor adds delays which could be leveraged testing the individual stages as they are made/delivered. If you test them together, and if there is an issue with one engine, you may have to test fire all three again adding extra firings to the other stages that have no problems.

It makes more sense to test them as they are built, work out any issues with stages individually (in the already tried and true process) then (as stated so aptly above).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 05/04/2016 11:34 pm

Yay, numbers! Thank you. I noticed you used the SL Isp down the line, is there any good way to refine that? I'm thinking linearization against atmospheric density but I don't know the specifics on how atmosphere/pressure/(velocity?) affect Isp.

You are welcome.

Yes I use sea level ISP and the reason I do is I trade being conservative there off against losses to air resistance and gravity losses on the centre core and 2nd stage (which are minor, but exist). I do account for gravity loss on the side cores though.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 05/05/2016 02:02 am
People were discussing this. The current guess is: they will test single sticks one after another in McGregor but the final integration and static fire of FH will happen in Florida. One of the reasons: no sign of triple core hold-down hardware at McGregor.

Spacex Kremlinology question: does this imply anything long term about how FH fits (or doesn't) into the current ecosystem of Hawthorne-build, Mcgregor-test, FL/Vandy-launch?
Well, note that they're already doing all the inspection/test/validation/refurb work for the recovered cores at the Cape.  So they must have already built up their test stand/equipment/engineer infrastructure at the Cape.  Testing/validating FH would presumably build on those resources.

There is speculation that MCT might be built/tested/flown all at the Cape.  If so, this might be a baby step in that direction.  But you don't need MCT to justify it---they clearly intend to recover and refly more and more cores, and they don't want to have to ship cores back and forth to McGregor.  So there will certainly be increased capabilities at the Cape over time.  Assuming a large proportion of recovered/reflown stages in some years time, I wouldn't be surprised to see McGregor transition more to Raptor/MCT R & D, with new-stage validation work less frequently required.

They'll probably need to eventually do refurb/validation work at Vandenberg, too.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Arcas on 05/05/2016 02:10 am
I can't wait for rocket boneyards like we have with aircraft.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 05/05/2016 04:59 am
There is speculation that MCT might be built/tested/flown all at the Cape.

There is no way SpaceX would do that unless the range is ready to support daily flights.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 05/05/2016 12:59 pm
There is speculation that MCT might be built/tested/flown all at the Cape.

There is no way SpaceX would do that unless the range is ready to support daily flights.
I'm not endorsing that theory, just reporting it.  As the rest of my post argues, you don't need to believe in MCT at the Cape in order to expect continuing migration of test/validation/refurb work from McGregor to the Cape.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/05/2016 01:09 pm

Well, note that they're already doing all the inspection/test/validation/refurb work for the recovered cores at the Cape.  So they must have already built up their test stand/equipment/engineer infrastructure at the Cape.


There was nothing to build up.  There is no difference in the GSE needed to prepare a new vehicle for launch or a previously flown vehicle.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/05/2016 01:11 pm
People were discussing this. The current guess is: they will test single sticks one after another in McGregor but the final integration and static fire of FH will happen in Florida. One of the reasons: no sign of triple core hold-down hardware at McGregor.

They may only static fire one or two FH at the Cape.  Static fire at the Cape for F9 is going to go away
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mike_1179 on 05/05/2016 01:19 pm
People were discussing this. The current guess is: they will test single sticks one after another in McGregor but the final integration and static fire of FH will happen in Florida. One of the reasons: no sign of triple core hold-down hardware at McGregor.

They may only static fire one or two FH at the Cape.  Static fire at the Cape for F9 is going to go away

For how long did other expendable launch vehicles do static fires before they moved to the wet dress rehearsal that ULA does now? Is the fact that SpaceX has continued to do firings instead WDR this long out of the ordinary?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/05/2016 02:33 pm

For how long did other expendable launch vehicles do static fires before they moved to the wet dress rehearsal that ULA does now? Is the fact that SpaceX has continued to do firings instead WDR this long out of the ordinary?

Only Delta IV did one static fire.  You would have to go back to the 50's for other vehicles static fires.  And it wasn't static fires or WDRs, they did both.  They continued with WDR's.  Shuttle did one static fire for new orbiters and then didn't do WDR's. Atlas doesn't do anything now. Any problem that WDR would uncover would be found during the launch countdown.  They see it as only a schedule risk. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 05/05/2016 02:46 pm
They may only static fire one or two FH at the Cape.  Static fire at the Cape for F9 is going to go away
Even with a reused core?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/05/2016 02:48 pm
They may only static fire one or two FH at the Cape.  Static fire at the Cape for F9 is going to go away
Even with a reused core?

don't know about that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/05/2016 02:48 pm
I've always seen Static Fires as a SpaceX practice to establish confidence in hardware (both ground and flight), people and vet procedures. 

Even now they don't have that many reps on launching and they are continuously changing things.  Jim's right, they will go away once the confidence level is high enough and the launch team and hardware mature enough. 

Finally if they want to launch every 2 weeks the static fire has to go away.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/05/2016 02:50 pm
Also, think about this.  If you are getting good at building engines and are seeing little to no issues for individual qual firings, why not eliminate them and do it at the same time as the stage qual firings. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 05/05/2016 03:08 pm
They may only static fire one or two FH at the Cape.  Static fire at the Cape for F9 is going to go away
Even with a reused core?
don't know about that.

That is likely a SpaceX goal for used stages eventually, once they characterize how useful engine performance data from the previous flight is.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/05/2016 03:28 pm
Eliminating the stop in McGregor would be a huge schedule improvement. 

Maybe they drop that step first and keep the static fire in Florida.  Reducing the number of stops, handling and shipping time.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 05/05/2016 03:38 pm
Eliminating the stop in McGregor would be a huge schedule improvement.
The testing in McGregor still seems to be more extensive (longer burn time) than a static fire, although there have been some recent reports from residents that the full S1 burns of earlier testing stopped a while ago.  With more pads scheduled to come on-line soon it does seem like McGregor would become more and more of a bottleneck, and especially wasteful for Vandenberg flights.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/05/2016 03:54 pm
Eliminating the stop in McGregor would be a huge schedule improvement. 

Maybe they drop that step first and keep the static fire in Florida.  Reducing the number of stops, handling and shipping time.

No, the other way around
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 05/05/2016 05:49 pm
Eliminating the stop in McGregor would be a huge schedule improvement.
The testing in McGregor still seems to be more extensive (longer burn time) than a static fire, although there have been some recent reports from residents that the full S1 burns of earlier testing stopped a while ago.  With more pads scheduled to come on-line soon it does seem like McGregor would become more and more of a bottleneck, and especially wasteful for Vandenberg flights.

Acceptance test firing of engines at McGregor is a crucial QA step, not "wasteful." Any bottleneck at McGregor would have to be solved by additional test stand capacity or some other means.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mike_1179 on 05/05/2016 07:05 pm

Acceptance test firing of engines at McGregor is a crucial QA step, not "wasteful." Any bottleneck at McGregor would have to be solved by additional test stand capacity or some other means.

You get a lot of data out of engine firings, not just "did the thing light up" or "how much force it produced". You could conceivably track these various variable data to determine if your manufacturing process is under control. If they really have stabilized all of the variables that flow down to acceptable engine performance, what's the point?

At some point, if you keep testing and you don't get failures (and everything behaves just as it should), it means your test isn't worth it. Instead of shipping engines from CA to TX back to CA for integration then the whole thing back to TX, make engines with a validated process in CA, integrate into a stage and test fire the whole thing. Any engine problems (have to be special cause because common cause is controlled) would be found there.

I'm extrapolating out from what we do in a non-rocket engine manufacturing industry so it may not be directly applicable.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 05/05/2016 07:36 pm
Acceptance test firing of engines at McGregor is a crucial QA step, not "wasteful." Any bottleneck at McGregor would have to be solved by additional test stand capacity or some other means.
As it stands, engines are shipped to McGregor, acceptance tested, shipped back to Hawthorne, integrated into an F9 1st stage, which is shipped to McGregor, the whole stage is tested, then shipped to launch site.

I'm talking about skipping the shipping of the 1st stage to McGregor for testing, not the engines.  I still don't know if the trades are worth it, but in any case you're talking about something different from what I was.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rsdavis9 on 05/05/2016 07:47 pm
I think the engine test at mcgregor after integration makes the most sense. Assuming that an integrated test can be just as thorough as individual engine tests.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Ronsmytheiii on 05/05/2016 07:54 pm
So right now for the 1st stage it is:

9 Individual engine firing in TX-> Integration to stage in CA -> Stage firing in TX-> Static Firing at Pad-> Launch

Eventually you sill see

Integration to stage in CA->Static Firing in TX-> Pad WDR-> Launch

And maybe further on get rid of the WDR entirely

If you want to launch as regularly as SpaceX states it does,  you have to get to the last flow.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dror on 05/05/2016 08:22 pm
Here's an article from SpaceFlight Now regarding possibility of a commercial payload during the first demonstration flight:

http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/ (http://spaceflightnow.com/2016/05/03/spacex-undecided-on-payload-for-first-falcon-heavy-flight/)


More from that article:
Quote
SpaceX’s updated pricing and performance chart shows a Falcon Heavy rocket lofting up to 8 metric tons to geostationary transfer orbit sells for $90 million. The performance figure assumes SpaceX recovers the boosters, but the price does not factor in reuse.

If so, than 90$m is for an expendable FH with 22ton to GTO too ?

Quote
Arianespace intends to sell the most powerful variant of the next-generation Ariane 6 rocket — the Ariane 64 with four solid rocket boosters — for 90 million euros, or about $103 million, a price to be typically split between two customers per mission once the new launcher enters service in 2020.

So Arian 6 is supposed to be a cheaper ride per sat than 2 F9s?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: joek on 05/05/2016 08:41 pm
More from that article:
Quote
SpaceX’s updated pricing and performance chart shows a Falcon Heavy rocket lofting up to 8 metric tons to geostationary transfer orbit sells for $90 million. The performance figure assumes SpaceX recovers the boosters, but the price does not factor in reuse.

If so, than 90$m is for an expendable FH with 22ton to GTO too ?

That statement in the article is wrong; looks like some misplaced "not".  The SpaceX capabilities page states $90M  for up to 8t to GTO; 22t to GTO fully expended.  The latter is the "performance figure" referenced in the article--fully expended, whereas the price is presumably based on some level of recovery (thus the lower 8t to GTO).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Doesitfloat on 05/05/2016 08:44 pm



More from that article:

SpaceX’s updated pricing and performance chart shows a Falcon Heavy rocket lofting up to 8 metric tons to geostationary transfer orbit sells for $90 million. The performance figure assumes SpaceX recovers the boosters, but the price does not factor in reuse.


If so, than 90$m is for an expendable FH with 22ton to GTO too ?



I read the reuse as the $90 million is for three new boosters, 1 new second stage, and two new fairing halves.
Further there might be an option to re-use some or all of the above components, but no pricing for that is available.

And... They are for 90 mil they are only selling the 8 tons to GTO performance.  Extra performance costs extra $$$
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dror on 05/05/2016 10:26 pm



More from that article:

SpaceX’s updated pricing and performance chart shows a Falcon Heavy rocket lofting up to 8 metric tons to geostationary transfer orbit sells for $90 million. The performance figure assumes SpaceX recovers the boosters, but the price does not factor in reuse.


If so, than 90$m is for an expendable FH with 22ton to GTO too ?



I read the reuse as the $90 million is for three new boosters, 1 new second stage, and two new fairing halves.
Further there might be an option to re-use some or all of the above components, but no pricing for that is available.

And... They are for 90 mil they are only selling the 8 tons to GTO performance.  Extra performance costs extra $$$

So you say -
it's 90$mil for a new reusable LV
it may be less for a reused reusable LV
and will probably be more for an expendable launch, new or reused LV.

There are at least these three configurations, not only two as I thought.

Thanks !
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GWH on 05/05/2016 10:50 pm
I would think more prices than just that.  Just for new cores you could have
Probably $90M is for 3 cores RTLS
Little more for central core ASDS
More again center core expendable
Then finally full expendable for top tier pricing.

Then used rocket pricing for all of the above modes.

In 2013 pricing when F9 was $56.5M for 4.85mT-GTO  FH was $77.1M for up to 6.4mT-GTO.  Above that (full expendable) price was $135M.
https://web.archive.org/web/20140316212646/http://www.spacex.com/about/capabilities
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RDMM2081 on 05/05/2016 11:38 pm
I would think more prices than just that.  Just for new cores you could have
Probably $90M is for 3 cores RTLS
Little more for central core ASDS
More again center core expendable
Then finally full expendable for top tier pricing.

Then used rocket pricing for all of the above modes.

In 2013 pricing when F9 was $56.5M for 4.85mT-GTO  FH was $77.1M for up to 6.4mT-GTO.  Above that (full expendable) price was $135M.
https://web.archive.org/web/20140316212646/http://www.spacex.com/about/capabilities

I believe your scale as what the actual price list and capabilities will look like when all is said and done, but there's the inconvenient little bit about the disclaimer at the bottom of the infographic on http://www.spacex.com/about/capabilities mentioning

*Performance represents max capability on fully expendable mode

But we know SpaceX has made several revisions of changes to that page in the last few days, and we all generally assume they are sandbagging the FH numbers until they launch and get some of their much loved data back in house, but I definitely see that statement on their website as being either flat out wrong or not up to date yet.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 05/06/2016 02:26 am
I don't think it's an accident that the FH for $90m is for 8mT, which can be covered by the Falcon 9 expendable.

Reuse is not technically on the critical path. They could launch those $90m payloads on expendable Falcon 9s. So while they do seem to plan to get the benefit of reuse for these Falcon Heavy payloads, technically that isn't required.

So yes, they can still legitimately claim that their prices don't require reuse (but if reuse doesn't work, they would need to use a Falcon Heavy without boosters... a Falcon 9).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: macpacheco on 05/06/2016 07:04 am
What are the odds SpaceX will take two of those stages as the side boosters for the first Falcon Heavy ?
Or perhaps make the next few F9 boosters in a way they could be reused as FH side boosters ?
Or am I just dreaming...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: douglas100 on 05/06/2016 08:00 am
As I understand it, the FH side boosters have high commonality with the F9 stage 1 but not with the F9 centre core. So re-use of F9 cores on FH may only apply to the boosters.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: macpacheco on 05/06/2016 08:51 am
What are the odds SpaceX will take two of those stages as the side boosters for the first Falcon Heavy ?
Or perhaps make the next few F9 boosters in a way they could be reused as FH side boosters ?
Or am I just dreaming...
If a used booster is less valuable than a new one, it would make more sense to use them for FH cores, since they're less likely to be recovered.
Some reasons to use the stages first as Falcon 9, then as FH:
1-SpaceX has a large backlog of F9 launches with payloads ready apparently they are arriving at the Cape about a month prior to launch, so it seems they have been waiting for a rocket. FH have already been stated won't fly until at least early fall
2-Building the first FH 2/3 with used hardware makes it cheaper to put together the first launch, cheaper price for the first customer
3-SpaceX might combine the first reflight of a stage as part of the FH launch. Waiting a few more months helps SX nail the landing process and increase the odds all 3 sticks will be recovered as part of the first launch. Current payloads are paying probably normal prices, while the first FH launch is expected to go for an ultra low price

It looks like SpaceX will need some hangars with room to store 5 sticks bare minimum. Ideally a 10 stage hangar.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 05/06/2016 02:30 pm
Static firing make a lot of sense - it is very useful data for comparatively little risk.

With reusability being tweaked in, the static fire will also become less of a hassle - maybe it can be done on the same roll-out, just before launch.

As a last step, with reusability, the last flight might be used as the static fire equivalent. It depends on how SpaceX estimates the odds of damage during descent.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: douglas100 on 05/06/2016 08:58 pm

...Building the first FH 2/3 with used hardware makes it cheaper to put together the first launch, cheaper price for the first customer...

I don't think they'll do that for the first flight. Too risky.  I think they'll want to do the first couple of FH flights with pristine cores until they've had time to assess and understand the vehicle's performance. Also, a used FH central core will not be available until after the first flight.

Later, you could imagine used F9 cores being added to the mix. Note that this requires the interstage of each F9 being swapped for a nose cone which contains the thrusters. A bit of extra work required, but I guess nothing major.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 05/06/2016 10:37 pm
What are the odds SpaceX will take two of those stages as the side boosters for the first Falcon Heavy ?
Or perhaps make the next few F9 boosters in a way they could be reused as FH side boosters ?
Or am I just dreaming...

The odds are zero because Gwynne Shotwell has told SFN they are building 3 new cores for the first FH. The first one is under construction and she expects the other two to be built by sometime this summer, ready for testing in the fall.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: bulkmail on 05/08/2016 12:50 pm
Falcon Heavy LEO capacity before the FT modifications was 45t without crossfeed and 53t with crossfeed.

With FT modifications capacity is 54.4t without crossfeed. Hypothetically, if crossfeed is added and we use simple math the result is slightly below 65t (maybe somebody can provide a better estimate) - quite close to SLS Block I (but that's irrelevant, because it will fly only once, right? All subsequent SLS-es will be IB or II, if I understand correctly).

More importantly this 65t is matching the minimum requirement for BA-2100. At the same time Falcon 9 FT now has enough LEO capacity for BA-330.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: macpacheco on 05/08/2016 02:55 pm
What are the odds SpaceX will take two of those stages as the side boosters for the first Falcon Heavy ?
Or perhaps make the next few F9 boosters in a way they could be reused as FH side boosters ?
Or am I just dreaming...

The odds are zero because Gwynne Shotwell has told SFN they are building 3 new cores for the first FH. The first one is under construction and she expects the other two to be built by sometime this summer, ready for testing in the fall.
Plans change...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dmitry_V_home on 05/08/2016 06:10 pm

With FT modifications capacity is 54.4t without crossfeed. Hypothetically, if crossfeed is added and we use simple math the result is slightly below 65t (maybe somebody can provide a better estimate) - quite close to SLS Block I (but that's irrelevant, because it will fly only once, right? All subsequent SLS-es will be IB or II, if I understand correctly).


About 64 t
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/08/2016 07:50 pm
What are the odds SpaceX will take two of those stages as the side boosters for the first Falcon Heavy ?
Or perhaps make the next few F9 boosters in a way they could be reused as FH side boosters ?
Or am I just dreaming...

The odds are zero because Gwynne Shotwell has told SFN they are building 3 new cores for the first FH. The first one is under construction and she expects the other two to be built by sometime this summer, ready for testing in the fall.
Plans change...

Not for this
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Wolfram66 on 05/13/2016 01:46 pm
For Falcon 9 Heavy demo... TLI free return, but carry along a Lunar X Prize lander in trunk to eject when flying past. Free ride and big serving of crow for those not willing to push the envelope and think outside the box
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 05/13/2016 02:12 pm
For Falcon 9 Heavy demo... TLI free return, but carry along a Lunar X Prize lander in trunk to eject when flying past. Free ride and big serving of crow for those not willing to push the envelope and think outside the box
SpaceX isn't a charity.  I have to believe they'd prefer cold hard cash to a stunt.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kansan52 on 05/13/2016 03:13 pm
Makes me wonder, is part of the FH Demo delay caused by a payload that isn't ready yet?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rpapo on 05/13/2016 03:17 pm
Makes me wonder, is part of the FH Demo delay caused by a payload that isn't ready yet?
I doubt it, though it certainly removes a good deal of pressure from the debut.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TrueBlueWitt on 05/13/2016 04:17 pm

With FT modifications capacity is 54.4t without crossfeed. Hypothetically, if crossfeed is added and we use simple math the result is slightly below 65t (maybe somebody can provide a better estimate) - quite close to SLS Block I (but that's irrelevant, because it will fly only once, right? All subsequent SLS-es will be IB or II, if I understand correctly).


About 64 t

Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Just thinking if you did need more payload.. This might still be easier than cross feed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Roy_H on 05/13/2016 04:44 pm
Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Just thinking if you did need more payload.. This might still be easier than cross feed.
Intriguing idea. A way to create a much bigger 2nd stage without a lot of new development. But it appears that the new Raptor powered 2nd stage is the chosen path forward.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/13/2016 04:54 pm
Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Just thinking if you did need more payload.. This might still be easier than cross feed.
Intriguing idea. A way to create a much bigger 2nd stage without a lot of new development. But it appears that the new Raptor powered 2nd stage is the chosen path forward.

Plus, the FH can already hoist more mass than any commercial payload.  No need
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Bynaus on 05/13/2016 04:57 pm
Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Just thinking if you did need more payload.. This might still be easier than cross feed.
Intriguing idea. A way to create a much bigger 2nd stage without a lot of new development. But it appears that the new Raptor powered 2nd stage is the chosen path forward.

Let me just repeat here that we shouldn't take the Raptor upper stage for granted. The contract with the AF is very vague on the matter (technically its about development of an upper stage engine, not an upper stage), and we have never heard any confirmation from anyone at SpaceX (to my knowledge) that they are actually working towards a Raptor-based upper stage for the Falcon family. Just saying.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 05/13/2016 05:11 pm
Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Just thinking if you did need more payload.. This might still be easier than cross feed.
Intriguing idea. A way to create a much bigger 2nd stage without a lot of new development. But it appears that the new Raptor powered 2nd stage is the chosen path forward.

Adding more tanks with Merlin vac engines would take some significant structural modification to the interstages because booster separation is sideways where core S1/S2 separation is axial so the Mvac bell clears the interstage. If the booster interstage have engine bells inside them they can separate sideways.

There's several to approach this:
 - separate sideways but split the interstage like a fairing and keep the inside half of the side interstages tied to the core booster
 - keep the core and boosters linked and separate all three axially simultaneously
 - make the side S2's into drop tanks (or fixed tanks) with no engines so there's no bell clearance worries at all
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/13/2016 05:13 pm

Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Just thinking if you did need more payload.. This might still be easier than cross feed.

Not really easier and actually more complex. Will even make pad ops more complex.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TrueBlueWitt on 05/13/2016 05:33 pm

Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Just thinking if you did need more payload.. This might still be easier than cross feed.

Not really easier and actually more complex. Will even make pad ops more complex.

Understood, It was a question.

What about as opposed to complexity and cost of switching to a Raptor based S2? Could you match that performance?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TrueBlueWitt on 05/13/2016 05:36 pm
Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Just thinking if you did need more payload.. This might still be easier than cross feed.
Intriguing idea. A way to create a much bigger 2nd stage without a lot of new development. But it appears that the new Raptor powered 2nd stage is the chosen path forward.

Adding more tanks with Merlin vac engines would take some significant structural modification to the interstages because booster separation is sideways where core S1/S2 separation is axial so the Mvac bell clears the interstage. If the booster interstage have engine bells inside them they can separate sideways.

There's several to approach this:
 - separate sideways but split the interstage like a fairing and keep the inside half of the side interstages tied to the core booster
 - keep the core and boosters linked and separate all three axially simultaneously
 - make the side S2's into drop tanks (or fixed tanks) with no engines so there's no bell clearance worries at all

I had considered such scenarios. I'd figured you'd stage with all 3 S1 connected. Then separate them after staging.

 Just  too much to type on my phone.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 05/13/2016 05:47 pm


What about as opposed to complexity and cost of switching to a Raptor based S2? Could you match that performance?

As a general rule having multiple cores is inefficient. It's a performance slap excusable for booster stages but not for the second stages of TSTO LVs. It's just extra metal for volume.

A raptor upper stage would certainly provide more performance and would definitely be cheaper to operate once you get into the swing of things. the Rvac stage might be reusable for all we know, which would massively cut upper stage costs.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 05/13/2016 05:58 pm

With FT modifications capacity is 54.4t without crossfeed. Hypothetically, if crossfeed is added and we use simple math the result is slightly below 65t (maybe somebody can provide a better estimate) - quite close to SLS Block I (but that's irrelevant, because it will fly only once, right? All subsequent SLS-es will be IB or II, if I understand correctly).


About 64 t

Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Just thinking if you did need more payload.. This might still be easier than cross feed.

Aside from complexity/cost/separations increase, performance would not benefit much.

Too much US weight (thicker sidewalls) and not long enough burn for 3 Merlin Vacs. Not enough booster thrust for US/payload to benefit.

If we discard all complexity/risk/engines and have new launcher/integration (vertical?), five boosters with three having US would about work. Then the issues would be about structural issues/load paths. Modern OTRAG variant? >110T?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/13/2016 06:41 pm

Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Just thinking if you did need more payload.. This might still be easier than cross feed.

Not really easier and actually more complex. Will even make pad ops more complex.

Understood, It was a question.

What about as opposed to complexity and cost of switching to a Raptor based S2? Could you match that performance?

The way the heavies work (Delta IV, FH, and Titan III/IV) and keep the same second stage of the single stick version is that the central core becomes an upper stage.  Whether it ignites on the ground or inflight, the central core burns for some time after the strap on cores are jettisoned. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gongora on 05/13/2016 06:52 pm
Makes me wonder, is part of the FH Demo delay caused by a payload that isn't ready yet?

SpaceX lost a payload due to launch in that timeframe because FH has been delayed so much.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 05/13/2016 07:52 pm

Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Rocket stages are not like LEGO elements!!! :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Ronsmytheiii on 05/13/2016 11:47 pm
Booster Nose cone spotted outside the factory:

https://www.instagram.com/mc_design91/?hl=en
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TrueBlueWitt on 05/14/2016 12:18 am

Would there be any benefit to going to three full stick F9 where you link both S1 and S2? Stage all 3 S1 at the same time then burn the outer two S2  to depletion then use the center core as S3 for the payload?

Rocket stages are not like LEGO elements!!! :)

At least I'm not trying to put LEGOs and DUPLOs together! My LEGOs are really LEGOs, minus a few attachments.  ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Herb Schaltegger on 05/14/2016 12:38 am
Booster Nose cone spotted outside the factory:

https://www.instagram.com/mc_design91/?hl=en

I love the "No SpaceX Deliveries" sign in the foreground. :p
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: BobHk on 05/14/2016 01:47 am
Booster Nose cone spotted outside the factory:

https://www.instagram.com/mc_design91/?hl=en

Looks like a LEGO
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mvpel on 05/14/2016 01:49 am
Looks like a LEGO

LEGO Falcon 9
(http://reprage.com/images/2016-02-20-falcon9-octaweb.jpg) (http://reprage.com/post/lego-falcon-9)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sanman on 05/14/2016 02:20 pm
Booster Nose cone spotted outside the factory:

https://www.instagram.com/mc_design91/?hl=en

I love the "No SpaceX Deliveries" sign in the foreground. :p

I love that the street sign says "Rocket Ave" - what's the name on the other street?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: HarryM on 05/14/2016 04:06 pm
Crenshaw

https://www.google.com/maps/@33.9215613,-118.3265733,3a,75y,219.39h,83.56t/data=!3m6!1e1!3m4!1seqWXrHoGZP6vrWS1ehsVcQ!2e0!7i13312!8i6656!6m1!1e1
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: matthewkantar on 05/14/2016 05:57 pm
It may be just extra paint over masking, but it looks like it was painted by a 3rd grader. Also looks like it was brushed on, any ideas about that?

Matthew
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Chris_Pi on 05/14/2016 06:10 pm
I was just going to say the paint job looked kinda rough, But who am I to argue with you?  ;)

They probably want roll/ID patterns on each nosecone and the regular paint shop may either be busy or not set up to do a couple of oddball pieces. Normal work is either straight cylinders or fairing halves. Grab some brushes and cans of paint and it's good enough. Will be interesting to see if the second one is painted a bit different.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sanman on 05/14/2016 06:12 pm
I wanted to ask about the central core - is there any chance that it could ever be made into a flyback booster? I know that sounds heterogenous, but I thought it might help the thing land back on land on a runway, rather than on the barge, or being discarded entirely.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/14/2016 07:10 pm
I wanted to ask about the central core - is there any chance that it could ever be made into a flyback booster? I know that sounds heterogenous, but I thought it might help the thing land back on land on a runway, rather than on the barge, or being discarded entirely.

no.  It take a whole bunch of mass and development.  The barge costs less
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dorkmo on 05/15/2016 05:49 am
Booster Nose cone spotted outside the factory:

https://www.instagram.com/mc_design91/?hl=en

a good view of what i assume is a hole for the grid fin mounts
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Johnnyhinbos on 05/15/2016 11:07 am

Booster Nose cone spotted outside the factory:

https://www.instagram.com/mc_design91/?hl=en
Are they taking it for a walk?

I'd assume it would be wrapped or in a container if being shipped to McGregor.

Where do they wind tunnel or thermal load test things this size?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/15/2016 12:49 pm
Booster Nose cone spotted outside the factory:

https://www.instagram.com/mc_design91/?hl=en

a good view of what i assume is a hole for the grid fin mounts

I'd guess it's a man way for access.  Gridfins will be in the interstate.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: eweilow on 05/15/2016 01:07 pm
Booster Nose cone spotted outside the factory:

https://www.instagram.com/mc_design91/?hl=en

a good view of what i assume is a hole for the grid fin mounts

I'd guess it's a man way for access.  Gridfins will be in the interstate.
There are no interstage on the FH Boosters though so they will surely be on the nose cone.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 05/15/2016 01:45 pm
Would there be an interstage on side booster?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Herb Schaltegger on 05/15/2016 02:13 pm
Would there be an interstage on side booster?

This raises a couple interesting points, when you stop and think about it. I think most of us on NSF have kind of assumed that the "interstage" of the FH booster cores would be an integrated composite barrel/nose cone structure inside which will be the stage avionics, grid fin hydraulics, etc.

So now, with that said, there must be a good degree of access to the internals for preflight processing as well as putative repair/refub/maintenance work on the avionics and mechanicals of the grid fin mechanisms. Is the entire nose cone portion removable (after it's initially assembled at the factory) in order to facilitate such work after recovery?

And more importantly, once the thing has landed, how does SpaceX plan to hoist it absent room to mount the "beanie cap?" Will SpaceX instead use some kind of 3- or 4-point shackle harness dangling from the crane to grab hard points built into the structure somewhere? Hopefully we'll get some detailed photos of things leading up to the Demo flight so we can try to figure this stuff out.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Johnnyhinbos on 05/15/2016 02:32 pm

Booster Nose cone spotted outside the factory:

https://www.instagram.com/mc_design91/?hl=en

a good view of what i assume is a hole for the grid fin mounts

I'd guess it's a man way for access.  Gridfins will be in the interstate.
Ah - so we don't know yet how the nose cones travel, but apparently the grid find take the interstate.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/15/2016 02:46 pm

Booster Nose cone spotted outside the factory:

https://www.instagram.com/mc_design91/?hl=en

a good view of what i assume is a hole for the grid fin mounts

I'd guess it's a man way for access.  Gridfins will be in the interstate.
Ah - so we don't know yet how the nose cones travel, but apparently the grid find take the interstate.

Doh, stupid autocorrect.  Yes Interstage. 

I don't think the grid fins will be in the nose cone.  Being on the curved part of the nose cone goes against their normal stowed position as well as being in a different place of the airflow.

Maybe it won't be a full Interstage but likely a truncated section with the same equipment and manufacture as the F9. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MP99 on 05/15/2016 02:52 pm


And more importantly, once the thing has landed, how does SpaceX plan to hoist it absent room to mount the "beanie cap?" Will SpaceX instead use some kind of 3- or 4-point shackle harness dangling from the crane to grab hard points built into the structure somewhere?

Just have a hoist point in the nose of the nose cone?

Would require plenty of strength in the nose cone - possibly permanently fit the shackle harness within the nose cone, so it can be attached during recovery operations.

Cheers, Martin
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: matthewkantar on 05/15/2016 03:32 pm
It looks like the item pictured is tall enough to be both interstage and nose cone. Save some mass on the interface at the cost of easy access?

Matthew
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: llanitedave on 05/15/2016 04:12 pm
Booster Nose cone spotted outside the factory:

https://www.instagram.com/mc_design91/?hl=en (https://www.instagram.com/mc_design91/?hl=en)

a good view of what i assume is a hole for the grid fin mounts

I'd guess it's a man way for access.  Gridfins will be in the interstate.


Grid fins on the interstate, nose cones on the sidewalk -- SpaceX is all over the place!
Title: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mvpel on 05/15/2016 04:29 pm
Where do they wind tunnel or thermal load test things this size?

Inside a computer.

Ansys Computational Fluid Dynamics Software (http://www.ansys.com/Products/Fluids)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: the_other_Doug on 05/15/2016 05:10 pm
Two questions and possible logical consequence...

1.  How much do y'all think the side booster nosecones weigh/mass?

2.  How much extra fuel/performance does it cost to land the mass of the side booster, including the nosecone, vs. landing just the side booster with no nosecone?

Possible logical consequence -- the side booster nosecones may be jettisoned and recovered in the sea, giving a small performance increase to the FH system as a whole.

One question -- in this kind of situation, is there a way of separating the nosecones from the boosters whole, without needing to split them like fairings split?  I'd think these may be more recoverable if you didn't have to split them in two.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/15/2016 05:23 pm
Two questions and possible logical consequence...

1.  How much do y'all think the side booster nosecones weigh/mass?

2.  How much extra fuel/performance does it cost to land the mass of the side booster, including the nosecone, vs. landing just the side booster with no nosecone?

Possible logical consequence -- the side booster nosecones may be jettisoned and recovered in the sea, giving a small performance increase to the FH system as a whole.

One question -- in this kind of situation, is there a way of separating the nosecones from the boosters whole, without needing to split them like fairings split?  I'd think these may be more recoverable if you didn't have to split them in two.

The animation shows them returning on the boosters and the grid fins on a short interstage as well as I can see it.
YMMV (it's an animation and artistic license is allowed)

Animation for FH near bottom of the page
http://www.spacex.com/falcon-heavy
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: yg1968 on 05/15/2016 06:39 pm
I am not sure if this is news:

http://www.universetoday.com/128815/spacex-maiden-falcon-heavy-launch-may-carry-satellite-in-november/

Quote
SpaceX’s Falcon Heavy rocket is set for its maiden launch this November. [...]

The payload for the maiden voyage is uncertain so far. According to Gwynne Shotwell, SpaceX’s President and CEO, a number of companies have expressed interest in being on the first flight. Shotwell has also said that it might make more sense for SpaceX to completely own their first flight, without the pressure to keep a client happy. But a satellite payload for the first launch hasn’t been ruled out.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/15/2016 06:39 pm
Two questions and possible logical consequence...

1.  How much do y'all think the side booster nosecones weigh/mass?

2.  How much extra fuel/performance does it cost to land the mass of the side booster, including the nosecone, vs. landing just the side booster with no nosecone?

Possible logical consequence -- the side booster nosecones may be jettisoned and recovered in the sea, giving a small performance increase to the FH system as a whole.

One question -- in this kind of situation, is there a way of separating the nosecones from the boosters whole, without needing to split them like fairings split?  I'd think these may be more recoverable if you didn't have to split them in two.

Not enough to impact performance
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 05/15/2016 07:16 pm
Two questions and possible logical consequence...

1.  How much do y'all think the side booster nosecones weigh/mass?

2.  How much extra fuel/performance does it cost to land the mass of the side booster, including the nosecone, vs. landing just the side booster with no nosecone?

Possible logical consequence -- the side booster nosecones may be jettisoned and recovered in the sea, giving a small performance increase to the FH system as a whole.

One question -- in this kind of situation, is there a way of separating the nosecones from the boosters whole, without needing to split them like fairings split?  I'd think these may be more recoverable if you didn't have to split them in two.

1. Unlikely to be significantly different than the interstage of the core.

2. Why... Why... Why would you make it so much more complex for a minuscule benefit!? You need to add extra separation hardware and  recovery hardware for the nose cone - when it *already* has an easy way to get down intact, staying attached to the core. And if there is ANY rocket on the near market that has plenty of performance margin for all likely payloads, it is FH.

"Possible logical consequence" - No, nothing logical about it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 05/15/2016 08:43 pm
Latest image off all 3 recovered cores inside 39A HIF begins to give a visual as to the FH.  That's going to be quite a site.

Linking to another post:

http://forum.nasaspaceflight.com/index.php?topic=38802.msg1534753#msg1534753
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sojourner on 05/15/2016 09:48 pm
That "nose cone" image. Is it possible that's actually the outer mold for making the nosecone?  I ask because the diameter looks a bit larger than what I would expect.  Of course, that could just be an optical illusion.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 05/15/2016 10:04 pm
Doh, stupid autocorrect

Yea, you got that right!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 05/15/2016 10:07 pm


And more importantly, once the thing has landed, how does SpaceX plan to hoist it absent room to mount the "beanie cap?" Will SpaceX instead use some kind of 3- or 4-point shackle harness dangling from the crane to grab hard points built into the structure somewhere?

Just have a hoist point in the nose of the nose cone?

Would require plenty of strength in the nose cone - possibly permanently fit the shackle harness within the nose cone, so it can be attached during recovery operations.

Cheers, Martin

The nose cone is a perfect auto-centering bullet-nose for the lift-cap that grabs the periphery of the top ring of the stage...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: the_other_Doug on 05/15/2016 10:31 pm
Two questions and possible logical consequence...

1.  How much do y'all think the side booster nosecones weigh/mass?

2.  How much extra fuel/performance does it cost to land the mass of the side booster, including the nosecone, vs. landing just the side booster with no nosecone?

Possible logical consequence -- the side booster nosecones may be jettisoned and recovered in the sea, giving a small performance increase to the FH system as a whole.

One question -- in this kind of situation, is there a way of separating the nosecones from the boosters whole, without needing to split them like fairings split?  I'd think these may be more recoverable if you didn't have to split them in two.

1. Unlikely to be significantly different than the interstage of the core.

2. Why... Why... Why would you make it so much more complex for a minuscule benefit!? You need to add extra separation hardware and  recovery hardware for the nose cone - when it *already* has an easy way to get down intact, staying attached to the core. And if there is ANY rocket on the near market that has plenty of performance margin for all likely payloads, it is FH.

"Possible logical consequence" - No, nothing logical about it.

Sure -- I was just thinking, if the nosecones were relatively heavy, and Elon's design teams were looking for an extra half-percent of performance, what-if...

Thanks, y'all, for a reasonable assessment of it.  I was thinking, too, that it would be a lot of hassle for a tiny performance increase, but wanted to get a feel for the size of increase you might get.  Good to know, it's not enough that we'd likely see these things come down flat-nosed.

In the final analysis, the side boosters will look so kewl coming down with the nosecones attached that I was hoping there wouldn't be a significant reason for dumping them...  :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 05/15/2016 11:03 pm
You should also keep in mind that the FH boosters will stage *earlier* that the FH core - and earlier that the F9 1st stage even - so the performance impact of a few extra lbs makes even less of a difference.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: 3Davideo on 05/15/2016 11:14 pm
...

2.  How much extra fuel/performance does it cost to land the mass of the side booster, including the nosecone, vs. landing just the side booster with no nosecone?

...

As far as I know, and this is with a mere undergraduate course in fluid dynamics, a very complicated subject, having the nosecone as the booster is coming down engine first would decrease drag because there'd be less turbulence as the air flow goes over and behind the booster. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GreenShrike on 05/16/2016 06:20 pm
You should also keep in mind that the FH boosters will stage *earlier* that the FH core - and earlier that the F9 1st stage even

Earlier than an F9 S1? If the FH boosters and F9 S1 have the same engines and same prop load, then won't they burn out (well, separate) at the same time, assuming the engine were operated at the same thrust levels? And that being booster stages, both the FH boosters and F9 S1 would operate at max thrust?

The FH boosters should only stage earlier than F9 S1 if they run out of ascent propellant before F9 S1. I can only see that if a) they reserve more prop for recovery and thus run out of ascent prop earlier; b) run at a higher thrust setting and thus consume their ascent prop faster; or c) have less ascent prop in general, by e.g. having smaller tanks (wrong as I believe the boosters and F9 S1 are essentially identical) or donating some of their prop to the central core (wrong as crossfeed isn't being implemented as yet).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 05/16/2016 06:27 pm
You should also keep in mind that the FH boosters will stage *earlier* that the FH core - and earlier that the F9 1st stage even

Earlier than an F9 S1? If the FH boosters and F9 S1 have the same engines and same prop load, then won't they burn out (well, separate) at the same time, assuming the engine were operated at the same thrust levels? And that being booster stages, both the FH boosters and F9 S1 would operate at max thrust?

The FH boosters should only stage earlier than F9 S1 if they run out of ascent propellant before F9 S1. I can only see that if a) they reserve more prop for recovery and thus run out of ascent prop earlier; b) run at a higher thrust setting and thus consume their ascent prop faster; or c) have less ascent prop in general, by e.g. having smaller tanks (wrong as I believe the boosters and F9 S1 are essentially identical) or donating some of their prop to the central core (wrong as crossfeed isn't being implemented as yet).

Note the asterisks around his *earlier* in the case of the FH centre core it is timing wise earlier because the core will throttle down (and presumably shut down engines) to end up with something like 50% of its prop load when the side cores separate. What I presume the asterisks denoted however is that rather than chronologically earlier time, in comparison with the F9 S1 it will be mission sequence earlier that is, at a lower altitude and slower velocity. That makes RTLS less costly in terms of propellant than on an F9 S1 and it also means that the impact to overall mission delta V would be much smaller than if it were carried to the equivalent altitude and speed of an F9 S1 MECO.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 05/16/2016 07:13 pm
You should also keep in mind that the FH boosters will stage *earlier* that the FH core - and earlier that the F9 1st stage even

Earlier than an F9 S1? If the FH boosters and F9 S1 have the same engines and same prop load, then won't they burn out (well, separate) at the same time, assuming the engine were operated at the same thrust levels? And that being booster stages, both the FH boosters and F9 S1 would operate at max thrust?

F9 S1 throttles down considerably (I think it actually shuts down some engines) before MECO to reduce g-loads.
It may also throttle down slightly for max-Q to reduce aerodynamic loads.

FH side boosters, on the other hand, are always running at full thrust.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/16/2016 07:34 pm

Earlier than an F9 S1? If the FH boosters and F9 S1 have the same engines and same prop load, then won't they burn out (well, separate) at the same time, assuming the engine were operated at the same thrust levels?

wrong assumption.  The way 3 core heavies work (Delta IV, FH, and Atlas V) with the same upper stage as the single core vehicle is for the center core to throttle down to reduce propellant usage.  This allows for the center core burn longer and in essence become a second stage.  Burning 3 cores all the same is just wasting propellant since the upper stage can't really take advantage of it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JasonAW3 on 05/16/2016 07:37 pm
     My thought here is that later Falcon Heavies will likely use a reused F9 stage one as the core stage, as it's less likely that it can or will be recoverable, as the twin F9 boosters are likely to be able to be recovered.

     If the core stage is recovered, hey bonus, but if lost, the cost is far less than losing a new F9 core stage, and thus a more acceptable loss.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/16/2016 07:39 pm
     My thought here is that later Falcon Heavies will likely use a reused F9 stage one as the core stage, a

The center core will be different than standard/booster cores.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 05/16/2016 07:55 pm
     My thought here is that later Falcon Heavies will likely use a reused F9 stage one as the core stage, a

The center core will be different than standard/booster cores.

With the recent Merlin updates FH with one expended core is expected to outperform Delta IV Heavy by a good margin to LEO and GTO; anyone launching payload in that class will probably want 3 new cores and not care much if SpaceX gets them back. Unless it's SpaceX paying for the launch.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: jongoff on 05/17/2016 12:01 am
     My thought here is that later Falcon Heavies will likely use a reused F9 stage one as the core stage, a

The center core will be different than standard/booster cores.

Jim's right--Elon said as much on Twitter today:
https://twitter.com/elonmusk/status/732329443776024576

In fact from this tweet it sounds like even the boosters aren't stock F9 stages, though close. Not sure if they can switch from a F9 single-stick stage to a booster stage later in life. I'll have to chew on the implications of that, but it is interesting.

~Jon
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 05/17/2016 05:17 am

In fact from this tweet it sounds like even the boosters aren't stock F9 stages, though close. Not sure if they can switch from a F9 single-stick stage to a booster stage later in life. I'll have to chew on the implications of that, but it is interesting.

~Jon

I don't know if it would make much sense to convert a F9 to a FH booster. I do wonder though why it would not be possible (sensible?) to use a FH booster as a stand alone launch vehicle, eliminating the need for building F9 cores in the future. Cost or something else?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jcc on 05/17/2016 09:58 am
     My thought here is that later Falcon Heavies will likely use a reused F9 stage one as the core stage, a

The center core will be different than standard/booster cores.

Jim's right--Elon said as much on Twitter today:
https://twitter.com/elonmusk/status/732329443776024576

In fact from this tweet it sounds like even the boosters aren't stock F9 stages, though close. Not sure if they can switch from a F9 single-stick stage to a booster stage later in life. I'll have to chew on the implications of that, but it is interesting.

~Jon

The side boosters are longer than the center core excluding interstage. The center core needs to be reinforced reletive to a stock F9 core to bear greater loading.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 05/17/2016 10:42 am
     My thought here is that later Falcon Heavies will likely use a reused F9 stage one as the core stage, a

The center core will be different than standard/booster cores.

Jim's right--Elon said as much on Twitter today:
https://twitter.com/elonmusk/status/732329443776024576

In fact from this tweet it sounds like even the boosters aren't stock F9 stages, though close. Not sure if they can switch from a F9 single-stick stage to a booster stage later in life. I'll have to chew on the implications of that, but it is interesting.

~Jon

Seems obvious that all cores of a F9H must be different to vanilla F9 cores - you need to 'bolt' them together for one!

But the engines are the same (AFAIK) , so you could take engines (and other parts) from a used F9 core and use them on a F9H core. Not fully reusable, but certainly recyclable.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cuddihy on 05/17/2016 11:15 am
So this time the naysayers, saying that the F9 and FH side boosters would be different, turned out to be right. 😀
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MATTBLAK on 05/17/2016 11:29 am
The engines, tankage, thrust structures and other equipment are made in the same factory by the same people, by the same designers - the difference is academic only and in that sense; hardly worth arguing about! Discussing, yes - but not arguing...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mike_1179 on 05/17/2016 12:36 pm
The engines, tankage, thrust structures and other equipment are made in the same factory by the same people, by the same designers - the difference is academic only and in that sense; hardly worth arguing about! Discussing, yes - but not arguing...

I guess we're into the "how different is it". There are differences between the stock CBC for single stick Delta IV launches and those used in the Delta IV Heavy. How do the differences in structure compare between Delta IV Heavy and CBCs and Falcon Heavy and F9s?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/17/2016 01:20 pm
Let's stay on target for people. 

This thread is getting to be about paper rockets.  Ther are other threads for that
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 05/17/2016 01:28 pm
Does anyone know the differences between the core and boosters?  And how different is those from the original Falcon 9?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 05/17/2016 03:06 pm
The engines, tankage, thrust structures and other equipment are made in the same factory by the same people, by the same designers - the difference is academic only and in that sense; hardly worth arguing about! Discussing, yes - but not arguing...

The Tesla S, made in the same factory as the Tesla X,  by the same people, by the same designers. The difference is NOT academic.

F9H Centre core takes some huge loads that an F9 core doesn't. As do the side cores. Either the centre or the sides needs mechanisms to release, F9 has nothing of the sort. Quite a few differences.

However, I expect a huge amount of commonality as well.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 05/17/2016 04:13 pm
It's worth keeping in mind that FH is also still under active development.  The first few FH side cores may differ in many ways from F9 just because when the F9 cores were built the FH design hadn't finalized yet.  We got a clear message that the *goal* is for FH side cores and F9 cores to be very similar.  Maybe that goal will change once they see exactly what FH needs.  Let's give it some time to see how that proves out once the FH is flying.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 05/17/2016 04:36 pm
I don't know if it would make much sense to convert a F9 to a FH booster.

I would imagine it could be impossible if the thickness or design of the tank material is different.

Quote
I do wonder though why it would not be possible (sensible?) to use a FH booster as a stand alone launch vehicle, eliminating the need for building F9 cores in the future. Cost or something else?

So far the demand for the Falcon Heavy is very low, yet demand for the current Falcon 9 is very high.  Adding unneeded weight to most of your launches just because of a few is not a good idea - it reduces the potential reusability of the Falcon 9 overall.

From a factory standpoint it's not that hard to produce multiple variations of the same product as long as they can be built on the same production line.  And SpaceX has the capacity to do this today, and if they can start reusing stages from LEO flights (like CRS flights to the ISS) they will have even more production capability available for the same amount of demand.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 05/17/2016 05:10 pm
I don't know if it would make much sense to convert a F9 to a FH booster.

I would imagine it could be impossible if the thickness or design of the tank material is different.

I was talking about boosters, maybe should have said side booster? But booster was usually used for the side boosters. The core is different.

The side boosters don't need to be stronger than Falcon 9. They need the connection joints. I don't know how much weight they would add, think not too much.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 05/17/2016 06:12 pm
     My thought here is that later Falcon Heavies will likely use a reused F9 stage one as the core stage, a

The center core will be different than standard/booster cores.

Jim's right--Elon said as much on Twitter today:
https://twitter.com/elonmusk/status/732329443776024576

In fact from this tweet it sounds like even the boosters aren't stock F9 stages, though close. Not sure if they can switch from a F9 single-stick stage to a booster stage later in life. I'll have to chew on the implications of that, but it is interesting.

~Jon

The side boosters are longer than the center core excluding interstage. The center core needs to be reinforced reletive to a stock F9 core to bear greater loading.

No, that's old info. The FH core and boosters are now the same length.

What distinguishes an FH booster from an F9 core is relatively minor, it involves changes at the base and top for attaching to the core (the octaweb is slightly different I believe). And a nose cone instead of an interstage, obviously.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mariusuiram on 05/18/2016 04:10 am

No, that's old info. The FH core and boosters are now the same length.

What distinguishes an FH booster from an F9 core is relatively minor, it involves changes at the base and top for attaching to the core (the octaweb is slightly different I believe). And a nose cone instead of an interstage, obviously.

So the take away is that for production-flow in the factory, FH Boosters and F9 cores are close enough thats its basically the same work flow with just a few minor modifications which gives them the production efficiency benefit. But the final product isnt interchangeable so they will remain stuck with their planned purpose. The FH core has significant differences to reinforce the core and therefore will have a substantially different work flow even though its the same factory and lots of similar parts.

To use an unnecessary Tesla analogy. The F9 core and FH boosters are like Model S with and without air suspension / tech package. The FH core is a Model X. The first two are basically the same vehicle but you'd never pull out / swap the modifications. The Last one is produced in the same factory and has common parts, but it clearly requires different work flows.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 05/18/2016 04:32 am
So the take away is that for production-flow in the factory, FH Boosters and F9 cores are close enough thats its basically the same work flow with just a few minor modifications which gives them the production efficiency benefit.

My background is in manufacturing operations, and that is my understanding.

Quote
But the final product isnt interchangeable so they will remain stuck with their planned purpose.

I think that is putting it a little harshly.  Each design is optimized for their intended use, with the benefit of still being able to be built on the same production line.

Quote
The FH core has significant differences to reinforce the core and therefore will have a substantially different work flow even though its the same factory and lots of similar parts.

Maybe I've missed some information that has been announced publicly, but I think all we know is that the Falcon Heavy core will be strengthened, and I'm not sure we know what that means design-wise or manufacturing flow-wise.

Quote
To use an unnecessary Tesla analogy. The F9 core and FH boosters are like Model S with and without air suspension / tech package. The FH core is a Model X.

I don't think Tesla analogies work at all for describing the differences between Falcon 9, Falcon Heavy cores, and Falcon Heavy boosters.  Let's just stick with describing SpaceX realities.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 05/18/2016 06:17 am
Do we know for certain, that the tank walls will be strengthened on the FH core? Or is it in the thrust structure and possible upper tank dome + interstage to provide more stiffness?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: alang on 05/18/2016 06:56 am
Quote
I don't think Tesla analogies work at all for describing the differences between Falcon 9, Falcon Heavy cores, and Falcon Heavy boosters.  Let's just stick with describing SpaceX realities.

Analogies are for explaining things to management. It always feels wrong somehow.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 05/18/2016 06:56 am
So the take away is that for production-flow in the factory, FH Boosters and F9 cores are close enough thats its basically the same work flow with just a few minor modifications which gives them the production efficiency benefit.

My background is in manufacturing operations, and that is my understanding.

Quote
But the final product isnt interchangeable so they will remain stuck with their planned purpose.
I think that is putting it a little harshly.  Each design is optimized for their intended use, with the benefit of still being able to be built on the same production line.

......Let's just stick with describing SpaceX realities.


This exchange nicely encapsulates part of the conundrum that I think FH gives to SpaceX.   If you generally accept efficiency as the ratio of what you get out of a system divided by the input to the system, FH appears to headed at best towards an indeterminate equation.   

A more honest SpaceX/FH reality is that it looks like mathematical manipulation to posit the low to zero cost & efficiency of maintaining capability to make a FH core on the common F9 assembly line as the proper metric to move the "input" of the FH system to zero $$, and thereby minimize & justify the poor efficiency of the system.   By forcing the denominator ( input ) towards zero, FH always looks like an acceptable product.  Even if it never fly's more than a few times, you can always point to how little effort/input is required to keep it around.   

At the root of this problem, it's not capturing the entire picture to use the efficiency of the assembly line as a metric for the efficiency of SpaceX as a business.   It's like ignoring the SGA line item of your P&L.   FH as it is configured, is not winning significant contracts ( output $$)  for generating revenue.  In the absence of that "output", the emphasis on minimized input distorts the inefficiency drag that FH has on the SpaceX business.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mme on 05/18/2016 07:46 am
So the take away is that for production-flow in the factory, FH Boosters and F9 cores are close enough thats its basically the same work flow with just a few minor modifications which gives them the production efficiency benefit.

My background is in manufacturing operations, and that is my understanding.

Quote
But the final product isnt interchangeable so they will remain stuck with their planned purpose.
I think that is putting it a little harshly.  Each design is optimized for their intended use, with the benefit of still being able to be built on the same production line.

......Let's just stick with describing SpaceX realities.

This exchange nicely encapsulates part of the conundrum that I think FH gives to SpaceX.   If you generally accept efficiency as the ratio of what you get out of a system divided by the input to the system, FH appears to headed at best towards an indeterminate equation.   

A more honest SpaceX/FH reality is that it looks like mathematical manipulation to posit the low to zero cost & efficiency of maintaining capability to make a FH core on the common F9 assembly line as the proper metric to move the "input" of the FH system to zero $$, and thereby minimize & justify the poor efficiency of the system.   By forcing the denominator ( input ) towards zero, FH always looks like an acceptable product.  Even if it never fly's more than a few times, you can always point to how little effort/input is required to keep it around.   

At the root of this problem, it's not capturing the entire picture to use the efficiency of the assembly line as a metric for the efficiency of SpaceX as a business.   It's like ignoring the SGA line item of your P&L.   FH as it is configured, is not winning significant contracts ( output $$)  for generating revenue.  In the absence of that "output", the emphasis on minimized input distorts the inefficiency drag that FH has on the SpaceX business.
I think the point of FH is to be able to do things like the upcoming Red Dragon missions on a reasonable budget.  It's definitely had an impact on the bottom line beyond the R&D of the FH in the sense that they needed to rebuild the TELs and make modifications to the pads.  But I don't see a cheaper way for them to get to the capability FH gives them.

I also think it will likely pick up a lot of the payloads that are expendable/risky on the F9 assuming SpaceX dials in reusing stages and the overhead of launching an FH is not too excessive.  That could shift the efficiency calculation considerably.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jet Black on 05/18/2016 08:42 am
In the absence of that "output", the emphasis on minimized input distorts the inefficiency drag that FH has on the SpaceX business.

One could say the same about BFR, since there is no call at all for a rocket that has a 15m core and the capacity that it has.  SpaceX's primary goal is not making money to please investors, though.

That said, BFR does not even exist as a rocket yet, and it is a bit early to say what the commercial use of it might be.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cuddihy on 05/18/2016 11:10 am

It's like ignoring the SGA line item of your P&L.   FH as it is configured, is not winning significant contracts ( output $$)  for generating revenue.  In the absence of that "output", the emphasis on minimized input distorts the inefficiency drag that FH has on the SpaceX business.


Ok, had to look up those acronyms. Not sure it's a good analogy for FH. FH has actually won contracts with an unproven configuration, without flying and despite sliding schedule right by a year every year or so... I think everyone wants to see this thing actually on the pad before committing funding & orbital slots / frequencies that require occupancy to keep.
 Even before seeing a successful launch, Viasat's schedule experience is a caution to ComSat investors. F9 and Dragon have successfully answered the question of whether SpaceX has the technical chops to pull off FH... Nothing has given confidence in schedule however just yet.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 05/18/2016 01:16 pm
Even if it never fly's more than a few times
If it never flies more than a few times, it is a failure, period.  And I think SpaceX would say the same.
Quote
FH as it is configured, is not winning significant contracts
You don't say, a rocket that has never flown hasn't won significant contracts?  Who woulda thunk?

Vulcan and Ariane 6 might as well pack it up and go home -- they haven't won any contracts at all!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/18/2016 03:40 pm

It's like ignoring the SGA line item of your P&L.   FH as it is configured, is not winning significant contracts ( output $$)  for generating revenue.  In the absence of that "output", the emphasis on minimized input distorts the inefficiency drag that FH has on the SpaceX business.


Ok, had to look up those acronyms. Not sure it's a good analogy for FH. FH has actually won contracts with an unproven configuration, without flying and despite sliding schedule right by a year every year or so... I think everyone wants to see this thing actually on the pad before committing funding & orbital slots / frequencies that require occupancy to keep.
 Even before seeing a successful launch, Viasat's schedule experience is a caution to ComSat investors. F9 and Dragon have successfully answered the question of whether SpaceX has the technical chops to pull off FH... Nothing has given confidence in schedule however just yet.

I'd be surprised if the market wasn't apprehensive about a booster with 27 engines.

Once it flys, successfully, a few times that will change.

Edit: Not trusting a SpaceX development schedule is just rational.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 05/18/2016 03:50 pm
I think FH delays are SpaceX polishing up landings, and final design changes on F9 FT.  Once they get them settled, FH will come on line with little if any problems. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Confusador on 05/18/2016 04:02 pm
I think FH delays are SpaceX polishing up landings, and final design changes on F9 FT.  Once they get them settled, FH will come on line with little if any problems.

I think the problem with that is the assumption that there will be "final" design changes.  Certainly it's a problem if you expect them to fly FH any time soon, since surely their newly returned hardware is inspiring a new round of design work.  The question is at what point FH becomes a priority.  If it were me, I would think soon, but SpaceX is somewhat more fanatical in the pursuit of reuse than I would be so they may well prove me wrong.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Norm38 on 05/18/2016 04:19 pm
And a nose cone instead of an interstage, obviously.

Minor quibble, but that's a nose cone on top of the interstage, yes?  The interstage has the RCS thrusters and grid fins.  Can't get rid of that and still land.  And I doubt there's much value in redesigning the interstage for the boosters just to shrink it a bit. Wouldn't want to change fin/thruster placement if I was them.

So just design a nose cone that snaps onto the existing mating points and call it.  - That's about the only change I would make.  Nose cone can be permanently attached, so can simplify the attachment (but not the mounting hard points).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 05/18/2016 04:24 pm
And a nose cone instead of an interstage, obviously.

Minor quibble, but that's a nose cone on top of the interstage, yes?  The interstage has the RCS thrusters and grid fins.  Can't get rid of that and still land.  And I doubt there's much value in redesigning the interstage for the boosters just to shrink it a bit. Wouldn't want to change fin/thruster placement if I was them.

So just design a nose cone that snaps onto the existing mating points and call it.

No, why would you ever do that? Are you *trying* to waste mass? The interstage is designed to carry ~100 tons above it - a nose cone can be made much lighter. The rcs thrusters and grid fins only take up a minor portion of the trunk, and can be incorporated into the base of a nose cone. Or have a very short cylindrical section that contains it under the nose cone. But you might as well put it all into one piece.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: neoforce on 05/18/2016 05:36 pm
Do we know for certain, that the tank walls will be strengthened on the FH core? Or is it in the thrust structure and possible upper tank dome + interstage to provide more stiffness?

Yes we do.  From https://twitter.com/elonmusk/status/732329443776024576, at 2:58 PM - 16 May 2016, Elon tweeted:

Quote
Falcon Heavy side boosters can use most of the same airframe as Falcon 9, but center core needs to be buffed up a lot for transfer loads.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Stan-1967 on 05/18/2016 05:47 pm
Even if it never fly's more than a few times
If it never flies more than a few times, it is a failure, period.  And I think SpaceX would say the same.
Quote
FH as it is configured, is not winning significant contracts
You don't say, a rocket that has never flown hasn't won significant contracts?  Who woulda thunk?

Vulcan and Ariane 6 might as well pack it up and go home -- they haven't won any contracts at all!

1.  SpaceX had the commercial cargo contract from NASA, as well as the existing F1 manifest committed to F9  before F9 had ever flown.

2.  ESA/Airbus-Safran are proposing a business case for Ariane 6 that survives on 4-6 launches a year guaranteed, plus upside for competing on other high value payloads.   Maybe they are right, maybe not, but they have commitments for expected payloads to close their business case for them.

3.  ULA with Vulcan also have no contracts, but they have expectations of business based on commitments from their customer base within the US government, and likely from industry as well.  Does it close a business case for them?   That appears to be sketchy based on the commitment of the parent companies.

4.  Can SpaceX say what contracts or commitments they think justify FH?  I haven't seen much in that regards.   From the outside cheap seats that I, and most here sit in, it's a case of "build it and they will come". 

My point about contracts won/lost is more to the expectation of FH having any type of positive impact on the SpaceX business, or the overall heavy payload class business for the immediate future. ( around 5 years, even as long as 10). 

I keep hearing that SpaceX's goal is not to make money.  That fine, if you believe that.   When it was E.Musk alone, his determination got them through the F1 failures.  However I think they now have it as a top goal to stay financially viable & profitable as part of their duty to their customers, as well as private investors.   
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: daveklingler on 05/18/2016 05:51 pm
I keep hearing that SpaceX's goal is not to make money.

From whom are you hearing that?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 05/18/2016 05:54 pm
You realize SpaceX has five FH flights contracted, right?  And if you look at the GTO payloads (commercial and DoD) that SpaceX is currently unable to compete for with the F9, it's pretty easy to see what potential market there is.

Quote
I keep hearing that SpaceX's goal is not to make money.

It's not my fault you're listening to the wrong people.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 05/18/2016 06:04 pm
I keep hearing that SpaceX's goal is not to make money.

From whom are you hearing that?
More correctly in my view: they are not next quarter focused, and money, while important to be made, is fuel for their ambition rather than the end goal.

But that may be a bit off topic.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Norm38 on 05/18/2016 06:28 pm
No, why would you ever do that? Are you *trying* to waste mass? The interstage is designed to carry ~100 tons above it - a nose cone can be made much lighter. The rcs thrusters and grid fins only take up a minor portion of the trunk, and can be incorporated into the base of a nose cone. Or have a very short cylindrical section that contains it under the nose cone. But you might as well put it all into one piece.

http://cdn.slashgear.com/wp-content/uploads/2014/11/spacex-x-wing-1.jpg
The above link shows a close-up of the interstage.  The RCS pod is high up, almost at the top.  And SpaceX is using the interstage as the location of the clamp-on ring for horizontal processing.  Would you move the RCS pod? (If so, why isn't it down there already?), and is there a reason why they're not supporting the stage below the grid fins?

If they don't want to move the RCS pods down, then is thinning the structure, having two separate designs, really worth the effort if it's still the same length?  If they can move the RCS, then sure, an all new design makes sense, but it's still engineering effort.

In summary, I don't see any need to redesign for the initial flights.  Not until they get to a point where they need more performance.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 05/18/2016 06:37 pm
4.  Can SpaceX say what contracts or commitments they think justify FH?  I haven't seen much in that regards.   From the outside cheap seats that I, and most here sit in, it's a case of "build it and they will come". 

SpaceX can't even try to fly a GTO payload over 8t without Heavy. If there's a business case for Atlas, Ariane, or DIVH, there is for Heavy also... especially when you consider that Heavy can fly nearly 15t to GTO while only expending an upper stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 05/18/2016 07:29 pm
Make no mistake about the differences between SX ambition, health as a provider, and addressable market.

Even if they were to just tweak what we've already seen, to the point where it became operationally (in the commercial sense) optimized, they might corner 30-40% of the global market share and depress world launch pricing more than 50% in most places. The landscape of the lower end of launch space would dramatically alter to fewer providers, and those would face margin pressure, and offer limited payload services. That's the "pre FH" market.

It makes perfect sense that they'd want that business humming (boring) before taking on FH. The unpredictable aspect of FH will be how much of the F9 operations improvements will carry over into FH. There are too few models to go on here.

DIVH suggests that it is likely to be difficult, but then DIV itself was IMHO an incompletely developed LV (long, long, long stories about pad, GSE, engine, stage systems, ...), so how much was a flawed singular LV that when tripled up magnified faults (my suspicion), or simply badly thought out CONOPs. It was also my impression that Boeing played to win at EELV, thinking that afterward a "second generation" version of everything would allow them to clean up the mess, that they'd then bill the taxpayer for.

So right now is actually the most critical time for FH, where getting F9 right makes FH build upon the economies of F9, rather than multiply the flaws by a factor of 3. In addition, we won't know about the minimum cost for integrating the three boosters properly. (Suggest that 18-20 day F9 launch recycle might be a good measure).

Also, what hasn't been talked about much is that even if the economies of F9 reuse alone might not be ideal, for FH they might be a lot better because of launch pricing/tiering. In addition, the combined system of FH+F9 might hold onto so much of the worldwide market share, depressing prices even further, that it might dry up budgets for rivals to the point that only "special need" vehicles that infrequently fly and can never get the launch frequency to mount a challenge - this, well before any BFR action (this is Jim's Demolition Man launch "Taco Bell" scenario - one of my favs, thank you Jim).

In the near term, FH is a mixed blessing for ULA - it allows them to leave the DIVH business, although then AF has a decision about SX's view of generic LV's - does AF "special case" payloads, "special case" pad facilities with a vendor, wait for Vulcan etc? Don't think SX will flex for AF much, because that might turn it into DIVH like economics that they've been avoiding. Suspect that AF will accommodate to generic LV's, and that Vulcan might follow suit after the fact if still functioning as a rival and not as a "special need" vehicle, so as to avoid cost growth.

Another issue is that of payload growth in the market. This may be influenced by SX pricing for FH, where transponder/antenna/power growth allows a competition, assuming FH can do so getting beyond DIVH's operational limits. We'd see that as sneaking up borderline F9 launches into FH territory. BTW this will kill off multiple launch on other rivals as this happens if it does.

As Ed Kyle explored on a ULA thread, the mystery payloads might also surface, where preliminary SC might be launched sooner given cost to accelerate programs rather than the heritage "test to death" on the ground. Those guys are also experimenting with agile development too. What better way than to check your work in space.

The other providers are simply waiting for SX to hit a brick wall, and then things go back to as before. That's an ostrich position which isn't warranted IMHO. Doubt SX will get all to their liking, but they may get what they need out of F9/FH, which is to drive the market into "competition requires > 50% reuse". Then next, ">90%".

Likely this means it drives most providers out of the significant part of the commercial business for more than a decade. And to reenter it, minimum $20B investment. "But launch is an insignificant part of the SC business ..."

Oops.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 05/18/2016 08:13 pm
Likely this means it drives most providers out of the significant part of the commercial business for more than a decade. And to reenter it, minimum $20B investment. "But launch is an insignificant part of the SC business ..."
20B? SpaceX has no way spent that much on development yet.... Is that saying that SpaceX got lucky multiple times, that they are much more efficient at development, or something else?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 05/18/2016 08:41 pm
4.  Can SpaceX say what contracts or commitments they think justify FH?  I haven't seen much in that regards.   From the outside cheap seats that I, and most here sit in, it's a case of "build it and they will come". 

My point about contracts won/lost is more to the expectation of FH having any type of positive impact on the SpaceX business, or the overall heavy payload class business for the immediate future. ( around 5 years, even as long as 10).

When thinking about possible customers for a particular rocket, in the past we knew what the expendable payload capabilities were of each rocket, and that defined what market they could go after.

However a reusable Falcon Heavy messes with that definition, since payload capability is not longer a limitation, and cost of service can now start being the primary consideration for a customer.

Since Falcon Heavy hasn't flown yet, and reusability hasn't been proven out yet, I don't think we've seen the real customer demand for this market niche.  So I think we need to wait before we can know for sure if the market will really be cost driven enough to risk flying on a reusable Falcon Heavy that matches the performance of an Ariane 5.

Quote
I keep hearing that SpaceX's goal is not to make money.  That fine, if you believe that.

Not sure where you heard that, but the goal of SpaceX is to make humanity multi-planetary.

What you may be confusing is that Musk has stated that taking SpaceX public does not make sense right now because public companies can be affected by pressure from stockholders to prioritize profit over other considerations, and Musk is not ready to give up pursuing those other considerations (i.e. making humanity multi-planetary).

Quote
When it was E.Musk alone, his determination got them through the F1 failures.  However I think they now have it as a top goal to stay financially viable & profitable as part of their duty to their customers, as well as private investors.

Musk is a capitalist, and understands how to make money while pursuing parallel goals.  And he has to make money to pursue his parallel goals.

SpaceX is a profit making enterprise, and I have no doubt that they goal is that it will continue to be one.  It's their only assured path towards making humanity multi-planetary.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Pipcard on 05/18/2016 08:47 pm
I'm wondering how much more dry mass would a FH core have compared to an F9 core.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 05/18/2016 09:20 pm
No, why would you ever do that? Are you *trying* to waste mass? The interstage is designed to carry ~100 tons above it - a nose cone can be made much lighter. The rcs thrusters and grid fins only take up a minor portion of the trunk, and can be incorporated into the base of a nose cone. Or have a very short cylindrical section that contains it under the nose cone. But you might as well put it all into one piece.

http://cdn.slashgear.com/wp-content/uploads/2014/11/spacex-x-wing-1.jpg
The above link shows a close-up of the interstage.  The RCS pod is high up, almost at the top.  And SpaceX is using the interstage as the location of the clamp-on ring for horizontal processing.  Would you move the RCS pod? (If so, why isn't it down there already?), and is there a reason why they're not supporting the stage below the grid fins?

If they don't want to move the RCS pods down, then is thinning the structure, having two separate designs, really worth the effort if it's still the same length?  If they can move the RCS, then sure, an all new design makes sense, but it's still engineering effort.

In summary, I don't see any need to redesign for the initial flights.  Not until they get to a point where they need more performance.

You know the interstage is mostly empty, right? And you know they they have already moved the RCS between the v1.1 and FT versions, I assume. So no, it is not a big deal to move them, you just run the propellant lines differently. The reason you want the RCS pod as high as reasonable is because of a slight increase in efficiency.  It (RCS & fins) will either be integrated into the nose cone, or put into a shortened cylinder just under the cone.

And your idea goes against all artwork (increasingly detailed) we have seen. Here is a picture to illustrate for you, the interstage size highlighted in green. I guess we're just going to have to see who's right...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: launchwatcher on 05/18/2016 09:22 pm
Likely this means it drives most providers out of the significant part of the commercial business for more than a decade. And to reenter it, minimum $20B investment. "But launch is an insignificant part of the SC business ..."
20B? SpaceX has no way spent that much on development yet.... Is that saying that SpaceX got lucky multiple times, that they are much more efficient at development, or something else?
SpaceX won't be standing still, either.   An aspiring competitor starting down this path will need to aim to be competitive with the future SpaceX, not the current one.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 05/18/2016 09:32 pm
Likely this means it drives most providers out of the significant part of the commercial business for more than a decade. And to reenter it, minimum $20B investment. "But launch is an insignificant part of the SC business ..."
20B? SpaceX has no way spent that much on development yet.... Is that saying that SpaceX got lucky multiple times, that they are much more efficient at development, or something else?

Something else.

Three issues - use of funds, competitive target you shoot for, and scope of technology required to "catch up".

All of these are different then how SX is getting entry to this new game of provider. Because things change after someone changes the way things works. This is why they have gotten it far cheaper than others to come.

Simplistic approach would be to build a copy, make it work, and do it quicker than SX because you know "what not to do". So lets say you do that. It will still take you time, funds, and effort, and none of that will be "risk free". So likely you'll accomplish the same thing, in the same time, for the same funds.

But by then, the market will have unalterably changed, you won't have the flight history, you won't have the advantages of operating the vehicle, cutting the deals, having grown to fit the customer "hand in glove".

Shorthand: since you cannot "be SX" just a copy of its earlier incarnation at best, you'll be at a disadvantage, and they will have all the advantages of undercutting you at every step. Which they will. So what have you gotten for this "best case" scenario? You haven't even pulled even, you might barely be in second place, probably with 10-25% market, and always second or worse.

And I haven't described any improvements on SX in that competitive analysis.

Shorthand for the rest: clearly you have to "overtake" while "catching up" in order to meet "head to head" as a true rival. But what you target is moving, and the cost factor comes in all of the unsecured, unearned "work" you have to do to maintain that intercept capability. You have someone already altering the market now, imagine what the market can be changed by them during the time to overtake them?

Likely this means it drives most providers out of the significant part of the commercial business for more than a decade. And to reenter it, minimum $20B investment. "But launch is an insignificant part of the SC business ..."
20B? SpaceX has no way spent that much on development yet.... Is that saying that SpaceX got lucky multiple times, that they are much more efficient at development, or something else?
SpaceX won't be standing still, either.   An aspiring competitor starting down this path will need to aim to be competitive with the future SpaceX, not the current one.



Yes ... and ... more.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RedLineTrain on 05/18/2016 10:13 pm
The other providers are simply waiting for SX to hit a brick wall, and then things go back to as before.

Agree on most of what you say, but at least Arianespace has explicitly said they would just follow SpaceX -- e.g., the infamous "they aren't supermen, so whatever they can do, we can do.  We would then have to follow" (https://www.youtube.com/watch?v=XZ-7nNw-04Q?t=3m27s) from Singapore Satellite 2013 @ 3 min, 27 seconds.

I see the same problems as you do with this approach.  Development takes so long in the space business that SpaceX could steal a 10-year march unless Arianespace is careful.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cuddihy on 05/18/2016 10:32 pm

Leapfrogging SpaceX's models will be hard to do. Old Space will have to change an awful lot of their business model.

I would argue this is what Bezos snd Blue Origin appear to be trying.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 05/18/2016 10:42 pm
The other providers are simply waiting for SX to hit a brick wall, and then things go back to as before.

Agree on most of what you say, but at least Ariane has explicitly said they would just follow SpaceX -- e.g., the infamous "they aren't supermen, so whatever they can do, we can do.  We would then have to follow" (https://www.youtube.com/watch?v=XZ-7nNw-04Q?t=3m27s) from Singapore Satellite 2013.

I see the same problems as you do with this approach.  Development takes so long in the space business that SpaceX could steal a 10-year march unless Ariane is careful.

Appreciate the fact that many American, European, Russian, Chinese, and more countries aerospace engineers are up to the task of doing a Buran, Concordski, various "me too's". Not really the issue.

The issue is the same one ULA has. Getting the funds/authorization/"field of action" to do so. Doesn't come easy, and the better bet is that they collectively ... don't. Until too late.

All you're hearing is pride talking. Europe surely has no stomach for such an exorbitant program - just like they don't have any stomach to field HSF vehicles. Could see quite a number of half measures to do pilot programs (like similar with HSF vehicles). The return would be insufficient. So likely they'd prop up a limited Ariane 6 program and backwater to a infrequently flown "super Vega" of some kind for "special launches". The Russians and the Chinese will be the last to "surrender", with the Chinese likely funding many concurrent programs at extreme expense.

Could easily see the failed attempts exceeding 100B accumulated expense, as they all "under estimate" scope, fall short, and retry. Because they won't be singular focused, having to retain too much of the past in competing programs that will internally "undercut" each other.

FWIW, if advising any competitive program, the best would be to create a "spin off" effort into an commercial company, with the tight focus on a small RLV to say, supplement propellant on orbit to a traditional vehicle, so as to develop the recoverable LV capability as fast as possible irrespective of ROI, because that can be a "pathfinder" that can be repurposed to market change rapidly (e.g. like Masten and XS-1). Then separately target successively larger vehicles following in its footsteps for special purpose markets, not unlike what BO is attempting (however BO intends only one "strand" of this multiple strand approach). That would position a rival to be ready to take advantage of a significant SX stumble, where then you attempt a comparable/larger capability offering.

Only American (or Chinese) could source that. But the face saving alone required might take a thousand years for that to happen, so its cultural issues in addition to political issues that challenge that.

And still that $20B number seems likely...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: SweetWater on 05/18/2016 10:44 pm

Leapfrogging SpaceX's models will be hard to do. Old Space will have to change an awful lot of their business model.

I would argue this is what Bezos snd Blue Origin appear to be trying.

Except Blue Origin isn't leapfrogging SpaceX or anyone else. They have some very impressive engineering accomplishments, but right now all they have demonstrated is a reusable first stage for a suborbital rocket. They haven't, AFAIK, released many details on the orbital system that will come after New Shepherd, but it will probably be a 2-stage-to-orbit vehicle, and it is hard to see why, for reasons of economy and the satellite market, it would have a payload significantly larger or smaller than Falcon 9, Atlas V, Delta 4M, etc. Maybe Bezos will have a 3 core heavy version, maybe not. Last I'd heard, more details were supposed to be forthcoming sometime this year.

SpaceX hasn't re-used a first stage yet, but it's hard to see any reason why they shouldn't be able to do that sometime this year. Blue origin might be right behind them in the re-usability game, but it is hard to imagine them getting leapfrogged by anyone anytime soon.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: the_other_Doug on 05/18/2016 11:22 pm

Leapfrogging SpaceX's models will be hard to do. Old Space will have to change an awful lot of their business model.

I would argue this is what Bezos snd Blue Origin appear to be trying.

Except Blue Origin isn't leapfrogging SpaceX or anyone else. They have some very impressive engineering accomplishments, but right now all they have demonstrated is a reusable first stage for a suborbital rocket. They haven't, AFAIK, released many details on the orbital system that will come after New Shepherd, but it will probably be a 2-stage-to-orbit vehicle, and it is hard to see why, for reasons of economy and the satellite market, it would have a payload significantly larger or smaller than Falcon 9, Atlas V, Delta 4M, etc. Maybe Bezos will have a 3 core heavy version, maybe not. Last I'd heard, more details were supposed to be forthcoming sometime this year.

SpaceX hasn't re-used a first stage yet, but it's hard to see any reason why they shouldn't be able to do that sometime this year. Blue origin might be right behind them in the re-usability game, but it is hard to imagine them getting leapfrogged by anyone anytime soon.

BO has yet to get any cash flow out of their re-used booster from paying customers.  At all.  They can re-use their toy rocket booster all they like -- until they get paid for using it, by someone (anyone), they're not leapfrogging anyone.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Herb Schaltegger on 05/19/2016 02:10 am
And the whole analogy was in relation to trying to catch up with SpaceX or leapfrog them. I am saying they are so far ahead that leapfrogging them is sheer fantasy, unless someone discovers some new laws of physics.

And that kind of thinking is hubris. SpaceX does not have a monopoly on smart people, money or knowledge. It MAY have an advantage in highly-driven and focused leadership, but that is subject to change at a moment's notice. And for that matter, a couple Bad Days in a short period may cause the money to dry up.

And before anyone starts talking hypersonic retro propulsion and pinpoint landing (or "impact" ;) ) guidance, anyone who follows Cold War nuclear history should have strong reasons to suspect that DOD and its contractors figured this stuff out decades ago for other purposes. It's only due to ITAR and related secrecy/compartmentalization rules that the tech hasn't been shared with the civil space side of the businesses. That could change in a relative eyeblink as well, if certain federal rule making or congressional interests decided it should.

So, in short: SpaceX better stay hungry for the foreseeable future. Life is what happens while you're busy making other plans.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: S.Paulissen on 05/19/2016 02:44 am
We can only HOPE that another company advances fast enough to overtake SpaceX in ten years... especially if SpaceX accomplishes even part of what they've set out to do.  In fact, I pray to the rocket gods (Heinlein, Goddard, Tsiolkovsky, von Brawn etc) nightly that this comes to pass as it truly would mark a turning point in human history.  Orbit would no longer be the province of the superrich and other huge entities. 

A bright future that way lies...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cuddihy on 05/19/2016 03:01 am

Leapfrogging SpaceX's models will be hard to do. Old Space will have to change an awful lot of their business model.

I would argue this is what Bezos snd Blue Origin appear to be trying.

Except Blue Origin isn't leapfrogging SpaceX or anyone else. They have some very impressive engineering accomplishments, but right now all they have demonstrated is a reusable first stage for a suborbital rocket. They haven't, AFAIK, released many details on the orbital system that will come after New Shepherd, but it will probably be a 2-stage-to-orbit vehicle, and it is hard to see why, for reasons of economy and the satellite market, it would have a payload significantly larger or smaller than Falcon 9, Atlas V, Delta 4M, etc. Maybe Bezos will have a 3 core heavy version, maybe not. Last I'd heard, more details were supposed to be forthcoming sometime this year.

SpaceX hasn't re-used a first stage yet, but it's hard to see any reason why they shouldn't be able to do that sometime this year. Blue origin might be right behind them in the re-usability game, but it is hard to imagine them getting leapfrogged by anyone anytime soon.

What Blue has demonstrated and announced plans for earning revenue from is actually not indicative of what I'm talking about.
I don't want to take this too far on a SpaceX thread, but it certainly appears Blue's investing an enormous amount of money and long-term planning and effort on things that aren't actually needed for the scale they're demonstrating at.
 -Why build such a complex large upper stage hydrolox engine (BE3) for atmospheric suborbital application? Unless you intend to use it for high energy upper stage missions.
 -Why put so much investment (even demonstration) into VTVL first stage reusability and then also build a massive methalox first stage engine (BE4) over-powered for a reusable medium or even heavy-sized first stage vehicle like F9/FH?

So it's just a few data points but Blue may be planning to potentially leapfrog FH with a much bigger reusable vehicle.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 05/19/2016 04:44 am
And the whole analogy was in relation to trying to catch up with SpaceX or leapfrog them. I am saying they are so far ahead that leapfrogging them is sheer fantasy, unless someone discovers some new laws of physics.

And that kind of thinking is hubris.

Agreed.

Quote
SpaceX does not have a monopoly on smart people, money or knowledge. It MAY have an advantage in highly-driven and focused leadership, but that is subject to change at a moment's notice. And for that matter, a couple Bad Days in a short period may cause the money to dry up.

Musk has selected many like him, and they move on things faster than having to say "mother may I" to the "parents" often. Also has some prizewinning jerks IMHO that slow him down but he doesn't seem to notice ATM.

SX is vulnerable because they leverage so much, perhaps too much at times. Many wins at the launch roulette table though.

Quote
And before anyone starts talking hypersonic retro propulsion and pinpoint landing (or "impact" ;) ) guidance, anyone who follows Cold War nuclear history should have strong reasons to suspect that DOD and its contractors figured this stuff out decades ago for other purposes. It's only due to ITAR and related secrecy/compartmentalization rules that the tech hasn't been shared with the civil space side of the businesses. That could change in a relative eyeblink as well, if certain federal rule making or congressional interests decided it should.

Familiar with this and left for greener pastures long BEFORE ITAR/etc . Mind you, that little blue dot on your cellphone map owes a lot to a commercial variation of related tech. And, guess what, Mars isn't like Earth in many ways, so precision terminal navigation to the same spot does not use the same recipe.

Congress can (and frequently does) complicate the landscape here, but whenever if fights a global technology shift to favor certain interests, it often undercuts American competitiveness, stepping on too much collective anatomy.

You'll notice a shift in the exploration focus to new exploration items (like habs in Congress today). That's a smart move to start playing a new game in a different area, one that SX has little apparent interest in. At some point the big guys pick up their toys and play a more suitable game. Have long though that the Nautilus-X approach much better suited those firms, rather than the "small market of launch", even HLV launch. Basically a roving ISS concept whose complexity/cost is playing at their level, and is way out of the scope of certain rivals.

Quote
So, I'm short: SpaceX better stay hungry for the foreseeable future. Life is what happens while you're busy making other plans.

What "starves" them IMHO is the aggressive approach they have/are taking for changing the aerospace industry's direction - unlike Bezos, they have to make it pay for itself the whole way, as they move the battleship with F9/FH tugboats. Cannot see them anything but hungry for foreseeable decades. ULA/Boeing/Safran et al isn't truly what they are after, these are things that get in the way.

Which is another issue for competing with them - if  the end SX is after isn't necessarily same as yours as a competitor, a competitive solution may be so difficult to access that the common price floor may not support your entry against them.

Like Sun-Tzu, the victory in battling them may simply be to not engage in the battle on their terms or field.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Arb on 05/19/2016 12:54 pm
Musk ... has some prizewinning jerks IMHO that slow him down but he doesn't seem to notice ATM.

Would be interesting to read more on the bit in bold if you can find a suitable thread.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 05/19/2016 01:37 pm

It's like ignoring the SGA line item of your P&L.   FH as it is configured, is not winning significant contracts ( output $$)  for generating revenue.  In the absence of that "output", the emphasis on minimized input distorts the inefficiency drag that FH has on the SpaceX business.


Ok, had to look up those acronyms. Not sure it's a good analogy for FH. FH has actually won contracts with an unproven configuration, without flying and despite sliding schedule right by a year every year or so... I think everyone wants to see this thing actually on the pad before committing funding & orbital slots / frequencies that require occupancy to keep.
 Even before seeing a successful launch, Viasat's schedule experience is a caution to ComSat investors. F9 and Dragon have successfully answered the question of whether SpaceX has the technical chops to pull off FH... Nothing has given confidence in schedule however just yet.

I'd be surprised if the market wasn't apprehensive about a booster with 27 engines.

Once it flys, successfully, a few times that will change.

Edit: Not trusting a SpaceX development schedule is just rational.

Why should a customer be apprehensive about 27 engines? SpaceX has flown almost 250 Merlins without catastrophic failure, and Heavy has margins to handle benign failure of multiple engines without loss of mission.

Schedule creep is obviously an issue with SpaceX, and the complexity of Heavy certainly doesn't help with that... though Heavy's schedule is probably driven more by other factors (pads, F9 recovery, payloads).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 05/19/2016 02:11 pm
I think the pads aren't ready for FH yet.  I think that is the biggest hold up.  Also, aren't they building more landing pads at the cape also, so FH boosters will have a place to land?  SpaceX may also need to build another building at or near the Cape to refurbish the landed boosters. 

With modern computers, 27 engines should not be a problem.  If they can throttle up the others to make up for one or so shut down, that shouldn't be a problem.  With their computers, they can pin point, throttle, and land a booster.  Launching should be easier. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LouScheffer on 05/19/2016 02:41 pm
Simplistic approach would be to build a copy, make it work, and do it quicker than SX because you know "what not to do". So lets say you do that. It will still take you time, funds, and effort, and none of that will be "risk free". So likely you'll accomplish the same thing, in the same time, for the same funds.
I strongly disagree with the with this.  It's always easier to design something if you have a working example to copy.  How big do those grid fins need to be?  Do what SpaceX did.  Sub-cool the LOX, and to what temperature?  Yes, do what SpaceX did.  How big of a barge do you need?  Do what SpaceX did....  You should get every major decision right the first time, and can order all your major equipment early, knowing that your approach can be made to work. 

This would be especially true if the design team has the support of any cyber-theft capability (as in Russia or China), in which case they would doubtless have the actual blueprints and CAD files, and not just external observations.  Even without this, the public  observations are pretty detailed - high res photos of the landed boosters, videos of the insides of the LOX tanks, etc.

So I think that if the designers can swallow their pride, and just do what SpaceX did, a design team could do it in half the time for half the cost.  If, on the other hand, if they try to improve the performance, or even just think their approach is better, then you're probably talking at least as long and at least as expensive.  Pioneering is hard work.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gin455res on 05/19/2016 02:50 pm
Does it have to be an exact copy?
How about 7 vikings in a hexaweb, plus one of ariannes hydrogen engines on the second stage?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: speedevil on 05/19/2016 03:33 pm
However no new physics is needed for a total game changer something like the hypersonic jet/rocket Sabre as a SSTO, which although a long shot is within the realm of physics and still unknown if it is achievable or just outside the realm of practical 1st half 21st century engineering technology.
EM drive is extremely questionable - though there are interesting external power options that look somewhat plausible.
http://authors.library.caltech.edu/3303/1/PARaipcp04a.pdf - for example.
This uses 300MW to launch 100kg of payload in a hydrogen propellanted SSTO.
Someone might tomorrow work out how to make ~100GPa carbon nanotube cables for only $1000/kg - at which point a tether starts to look real good, but that's even less clear how to forecast if investing in such a device is reasonable.

China was brought up earlier - and dismissed.
It's unclear if china might decide to go heavily for aerospace 'welfare' much as the USA did.
If it did, its massive productivity, might mean really quite large amounts of engineer time spent on rockets.
There are obvious ITAR concerns for anyone wishing to launch on Chinese rockets of course.

A random thought - the above Japanese thing uses H2 to get really quite large delta-v. It would be interesting in principle for S2 recovery of a raptor based S2 running methane.
Unfortunately, the ground infrastructure looks 'quite large'.
Several hundred megawatts of gyrotrons and about double that in electrical power to recover a stage would seem only reasonable at extremley high flight rates.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 05/19/2016 03:43 pm
Simplistic approach would be to build a copy, make it work, and do it quicker than SX because you know "what not to do". So lets say you do that. It will still take you time, funds, and effort, and none of that will be "risk free". So likely you'll accomplish the same thing, in the same time, for the same funds.
I strongly disagree with the with this.  It's always easier to design something if you have a working example to copy.  How big do those grid fins need to be?  Do what SpaceX did.  Sub-cool the LOX, and to what temperature?  Yes, do what SpaceX did.  How big of a barge do you need?  Do what SpaceX did....  You should get every major decision right the first time, and can order all your major equipment early, knowing that your approach can be made to work. 

This would be especially true if the design team has the support of any cyber-theft capability (as in Russia or China), in which case they would doubtless have the actual blueprints and CAD files, and not just external observations.  Even without this, the public  observations are pretty detailed - high res photos of the landed boosters, videos of the insides of the LOX tanks, etc.

So I think that if the designers can swallow their pride, and just do what SpaceX did, a design team could do it in half the time for half the cost.  If, on the other hand, if they try to improve the performance, or even just think their approach is better, then you're probably talking at least as long and at least as expensive.  Pioneering is hard work.

However if they followed this approach they would always be a generation behind the leader, and maybe their costs could be lower, but they would have to change a lot about how they did things to take advantage of the hardware cost benefit to still end up with an end user price that was competitive. All the while still being a generation of vehicle behind in both pricing (if you presume that SpaceX will continue to evolve to lower pricing) and capability.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: WizZifnab on 05/19/2016 05:59 pm
Simplistic approach would be to build a copy, make it work, and do it quicker than SX because you know "what not to do". So lets say you do that. It will still take you time, funds, and effort, and none of that will be "risk free". So likely you'll accomplish the same thing, in the same time, for the same funds.
I strongly disagree with the with this.  It's always easier to design something if you have a working example to copy.  How big do those grid fins need to be?  Do what SpaceX did.  Sub-cool the LOX, and to what temperature?  Yes, do what SpaceX did.  How big of a barge do you need?  Do what SpaceX did....  You should get every major decision right the first time, and can order all your major equipment early, knowing that your approach can be made to work. 

This would be especially true if the design team has the support of any cyber-theft capability (as in Russia or China), in which case they would doubtless have the actual blueprints and CAD files, and not just external observations.  Even without this, the public  observations are pretty detailed - high res photos of the landed boosters, videos of the insides of the LOX tanks, etc.

So I think that if the designers can swallow their pride, and just do what SpaceX did, a design team could do it in half the time for half the cost.  If, on the other hand, if they try to improve the performance, or even just think their approach is better, then you're probably talking at least as long and at least as expensive.  Pioneering is hard work.

However if they followed this approach they would always be a generation behind the leader, and maybe their costs could be lower, but they would have to change a lot about how they did things to take advantage of the hardware cost benefit to still end up with an end user price that was competitive. All the while still being a generation of vehicle behind in both pricing (if you presume that SpaceX will continue to evolve to lower pricing) and capability.

True, but a competitor may not have to try to be better than SpaceX.  They may just need to be good enough to be profitable (better than most).  They could then decide to spend their profits on R&D on a future gen approach to leapfrog.  Or they could decide to always keep cloning other's ideas.  This seems to have worked in other fields.  Obviously may not translate to a successful approach in space launch services.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 05/19/2016 08:12 pm
Apologize for igniting this tempest of posts that has taken this thread off topic. Suggest you carve up posts onto other threads to bicker about nuance/minutiae/TV broadcast technologies.

The point I was getting at is that you have to consider FH's arrival and impact in the larger context of how they work as a system, and to the significance of how it affects the market dynamics depending on how this goes, and what to look for.

Another observation - we see how long a single core takes following landing to be handled/processed. Now three might arrive, all at once. Not to mention an intervening recovery from a single core from other pad. Wouldn't that tie up a single  stage handling team for about a month? Rate limit?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomH on 05/19/2016 09:41 pm
we see how long a single core takes following landing to be handled/processed. Now three might arrive, all at once. Not to mention an intervening recovery from a single core from other pad. Wouldn't that tie up a single  stage handling team for about a month? Rate limit?

I think what they are focusing on right now is how to expedite that very thing. In another thread:

http://forum.nasaspaceflight.com/index.php?topic=40312.60

there is discussion of charring around the engine bases and severe damage to grid fins. The photos of the grid fins are astounding. (Scroll through p 4 of that thread.) They discuss thermal paint, insulation, simply making grid fins quickly detachable, disposable, and replaceable, etc. I think the topic of quick turn around and design tweaks will be a particular focus in coming months. Will it set FH back some more or slow the second FH flight? I don't know. But in my mind, better to resolve these things sooner than later and be able to reuse these cores as many times as possible and to do so as quickly as possible.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 05/20/2016 02:23 am
Arguably the "can Blue leapfrog SpaceX" stuff is off topic for this thread. But ok...
The HD stuff? That show's been cancelled. Reruns are broadcast in a channel you guys can't get... (We call it DURT)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: woods170 on 05/20/2016 09:36 am
Quote from: Urban Dictionary
DURT
More descriptive than the well-known "dirt," "durt" specifically describes the smegma and other assorted debris that accumulates underneath a rug in a home or dorm.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lampyridae on 05/20/2016 10:04 am
Quote from: Urban Dictionary
DURT
More descriptive than the well-known "dirt," "durt" specifically describes the smegma and other assorted debris that accumulates underneath a rug in a home or dorm.

In the Red Dwarf series, they had to edit out all the references to "durt" because it was 100x more offensive than "smeg" which was already 100x worse than any other 20th century swear word. The BBC could only allow so much swearing.

Back On Topic, parallel reprocessing (look I made a thing) of stages would probably just require doubling of current processing workforce, say. But that is already scaled on their core production anyway. So as more cores are recycled and you get fewer "fresh" ones, you simple transition those some folks and not have large workforce number fluctuations.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/20/2016 12:21 pm
we see how long a single core takes following landing to be handled/processed. Now three might arrive, all at once. Not to mention an intervening recovery from a single core from other pad. Wouldn't that tie up a single  stage handling team for about a month? Rate limit?

I think what they are focusing on right now is how to expedite that very thing. In another thread:

http://forum.nasaspaceflight.com/index.php?topic=40312.60

there is discussion of charring around the engine bases and severe damage to grid fins. The photos of the grid fins are astounding. (Scroll through p 4 of that thread.) They discuss thermal paint, insulation, simply making grid fins quickly detachable, disposable, and replaceable, etc. I think the topic of quick turn around and design tweaks will be a particular focus in coming months. Will it set FH back some more or slow the second FH flight? I don't know. But in my mind, better to resolve these things sooner than later and be able to reuse these cores as many times as possible and to do so as quickly as possible.

They just caught the bus...
They'll figure out what to do with it soon enough.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 05/20/2016 02:21 pm
If they get back the next few boosters and do not immediately start reusing them, where are they going to store all these boosters?

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mme on 05/20/2016 05:40 pm
Arguably the "can Blue leapfrog SpaceX" stuff is off topic for this thread. But ok...
The HD stuff? That show's been cancelled. Reruns are broadcast in a channel you guys can't get... (We call it DURT)
It may be marginally on topic but any sufficiently funded, sufficiently well run, and sufficiently committed company has the possibility of "leapfrogging" SpaceX.

I am a fan of SpaceX but I am perplexed by arguments that no one is likely to catch up to them.  Are we just arguing over whether it's 5, 10, or 20 years?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 05/20/2016 05:49 pm
[With apologies to Ricky Nelson "Garden Party"]

A F9 added to the rocket garden, as SX dog "caught more buses"
A chance to process more reflights, and redesign 1.3 again
When it got to the rocket garden, it was all FUBARed
Nothing recognizable, couldn't do reflight

But it's all right now, we learned recovery well
You see you can't refly every stage, you got to pick and choose
...
Someone opened up the hanger door and out stepped Elon Musk
Playing the crowd like a-ringin' a bell and lookin' like he should
You gotta recover LV's, need to have a lotta luck
But if recovered stages were all I got, rather do BFR

But it's all right now, we learned recovery well
You see you can't refly every stage, you got to pick and choose

An' it's all right now, yeah, learned my lesson well
You see, ya can't refly every stage, so you got to redesign 1.3

;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 05/20/2016 06:24 pm
4.  Can SpaceX say what contracts or commitments they think justify FH?  I haven't seen much in that regards.   From the outside cheap seats that I, and most here sit in, it's a case of "build it and they will come". 

SpaceX can't even try to fly a GTO payload over 8t without Heavy. If there's a business case for Atlas, Ariane, or DIVH, there is for Heavy also... especially when you consider that Heavy can fly nearly 15t to GTO while only expending an upper stage.
http://www.spacex.com/falcon9

Falcon 9, 8300kg to GTO (expendable implied)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 05/20/2016 06:58 pm
This is not the party thread. (and DURT == Dead and Under Review Threads)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 05/22/2016 02:18 pm
Since the F9 mission patches have 9 stars would the FH mission patches have 27?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: ugordan on 05/22/2016 02:39 pm
Since the F9 mission patches have 9 stars would the FH mission patches have 27?

The F9 mission patches demonstrably do not all have 9 stars.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 05/22/2016 02:47 pm
Since the F9 mission patches have 9 stars would the FH mission patches have 27?

The F9 mission patches demonstrably do not all have 9 stars.
My bad assumption. In reviewing all the patches and not just the last one, each patch uses the stars to fill the blank space so it is more of a random number. Thanks for correction of assumption.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Owlon on 05/23/2016 03:44 am
Since the F9 mission patches have 9 stars would the FH mission patches have 27?

The F9 mission patches demonstrably do not all have 9 stars.
My bad assumption. In reviewing all the patches and not just the last one, each patch uses the stars to fill the blank space so it is more of a random number. Thanks for correction of assumption.

I believe they add a star for each mission, or something along those lines.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: luinil on 05/23/2016 04:12 am
I believe they add a star for each mission, or something along those lines.

Just for the CRS missions no?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Chris Bergin on 05/24/2016 07:24 pm
Our guy at the Space Tech Expo says the SpaceX person there is saying they are still hopeful to debut Falcon Heavy this year (NET December). We'll write up direct quotes that come back.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Tomness on 05/24/2016 07:46 pm
Our guy at the Space Tech Expo says the SpaceX person there is saying they are still hopeful to debut Falcon Heavy this year (NET December). We'll write up direct quotes that come back.

Wish there was a dislike button :( Falcon Heavy needs to soar! I guess not having RUD on the first go will be even better :) Thanks for the guy at the Expo, please post lots of pics :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 05/24/2016 08:47 pm
Before people start reaching for their handkerchiefs, poo-pooing left and right and reaching for the Elon time meme, this delay was fairly likely. I'm not surprised that it's scheduled for December considering the vast number of other considerations they've had to work through this year.

Falcon heavy is reuse dependent. They likely want to relaunch and get landing a little more settled before launching FH. Remember Elon's message that they want to try to recover cores on their first flight?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/25/2016 12:45 am
Before people start reaching for their handkerchiefs, poo-pooing left and right and reaching for the Elon time meme, this delay was fairly likely. I'm not surprised that it's scheduled for December considering the vast number of other considerations they've had to work through this year.

Falcon heavy is reuse dependent. They likely want to relaunch and get landing a little more settled before launching FH. Remember Elon's message that they want to try to recover cores on their first flight?

Could they be considering certifying FH with USAF based on reused boosters or even all three previously-flown cores?  They don't apparently intend to fly it expendible at the start... maybe never.  Or maybe they'll just let USAF buy the new cores that will then be used for commercial at Boca Chica -- not a bad option either.  Looks to be the plan for F9, with NASA buying the new cores.  Interesting new possibilities.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GWH on 05/25/2016 05:36 am
I would think they want at least one used FH kicking around for 2018 and red dragon.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 05/25/2016 08:31 am
Falcon heavy is reuse dependent. They likely want to relaunch and get landing a little more settled before launching FH. Remember Elon's message that they want to try to recover cores on their first flight?

They need to build additional pads. We have heard they cannot even begin building them before July because of some birds nesting season.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: georgegassaway on 05/25/2016 08:34 am
IIRC, the First FH launch has been about six or so months away.... for the  last year and a half, if not longer.  Late May 2016 -> December 2016, over 6 months.....

Not intended as a bash, but not ignoring the facts that for example , IIRC, in Spring of 2015.... the first FH flight was due for Fall 2015.

Of course given all the progress with the pad and HIF, they are closer at least regarding GSE.  Would be nice to see one of those returned F9 cores do a test firing on 39A, which would also show how close they are with the pad facilities. Thing is though, that's something Musk said was going to happen shortly after the ORBCOMM-2 booster landed (as in, such a test firing at 39A would happen soon.  But it was quietly trucked over to LC-40 for a low-profile test firing instead).

They'll finally be making progress on FH launches if say 3 months from now, the projected launch has not slipped again. Instead of slipping say another 3 months.  When they are down to 2 months before a projected launch, I'll start to get more excited and start dusting away the grains of salt.   :)

- George Gassaway
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Brovane on 05/25/2016 02:24 pm
With the recent acknowledged performance of the F9 22,000kg to LEO, 8,300kg to GTO is there less of a need for the FH?  These performance numbers overlap all but the highest performance numbers for the Atlas-V.  Which gives the F9 a fairly wide range of payloads it can accommodate because if necessary the legs can be removed from the F9 and it can operate in fully expendable mode for maximum performance.  The F9 with it's performance of 22,000kg to LEO now meets the definition of a HLLV. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 05/25/2016 02:30 pm
With the recent acknowledged performance of the F9 22,000kg to LEO, 8,300kg to GTO is there less of a need for the FH?  These performance numbers overlap all but the highest performance numbers for the Atlas-V.  Which gives the F9 a fairly wide range of payloads it can accommodate because if necessary the legs can be removed from the F9 and it can operate in fully expendable mode for maximum performance.  The F9 with it's performance of 22,000kg to LEO now meets the definition of a HLLV. 

No, because F9 does not fly in the expended mode.  it takes CTO approval for any such mission.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: ugordan on 05/25/2016 02:38 pm
No, because F9 does not fly in the expended mode.  it takes CTO approval for any such mission.

Will be interesting to see if this changes if the GTO boosters consistently end up returning almost-FUBAR'd.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 05/25/2016 02:42 pm
IIRC, the First FH launch has been about six or so months away.... for the  last year and a half, if not longer.  Late May 2016 -> December 2016, over 6 months.....

Not intended as a bash, but not ignoring the facts that for example , IIRC, in Spring of 2015.... the first FH flight was due for Fall 2015.

Of course given all the progress with the pad and HIF, they are closer at least regarding GSE.  Would be nice to see one of those returned F9 cores do a test firing on 39A, which would also show how close they are with the pad facilities. Thing is though, that's something Musk said was going to happen shortly after the ORBCOMM-2 booster landed (as in, such a test firing at 39A would happen soon.  But it was quietly trucked over to LC-40 for a low-profile test firing instead).

They'll finally be making progress on FH launches if say 3 months from now, the projected launch has not slipped again. Instead of slipping say another 3 months.  When they are down to 2 months before a projected launch, I'll start to get more excited and start dusting away the grains of salt.   :)

- George Gassaway

Certainly - the infrastructure just isn't there yet for the date not to move right. But it's getting close. December might be possible since the infrastructure is approaching completion.

If not for the FH's reuse requirements, they probably could have stuck to an earlier date. Less considerations to play with and it'd be easier to prioritise labour hours accordingly. The current way seems the right way.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/25/2016 02:43 pm
With the recent acknowledged performance of the F9 22,000kg to LEO, 8,300kg to GTO is there less of a need for the FH?  These performance numbers overlap all but the highest performance numbers for the Atlas-V.  Which gives the F9 a fairly wide range of payloads it can accommodate because if necessary the legs can be removed from the F9 and it can operate in fully expendable mode for maximum performance.  The F9 with it's performance of 22,000kg to LEO now meets the definition of a HLLV.

1) SpaceX is attempting to leave the world of expendable rockets behind.

2) There are other planned uses for FH besides commercial and USG orbital payloads. 
These payloads are simply a means to a greater end in light of the company's vision.

3) Strapping three HLLVs together and lighting the fuse is... well, too much fun to drop for pragmatic reasons.
And then they all return to land (or sea) landings.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 05/25/2016 02:45 pm
No, because F9 does not fly in the expended mode.  it takes CTO approval for any such mission.
While that makes sense, that's the first I've heard of it.
Will be interesting to see if this changes if the GTO boosters consistently end up returning almost-FUBAR'd.
"almost-FUBAR'd" is a gross overstatement.  And clearly the CTO is more interested in making changes to the LV to improve its recovery and reuse characteristics, rather than throwing in the towel and just launching a high percentage of future F9 missions fully expendable.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Brovane on 05/25/2016 02:48 pm
With the recent acknowledged performance of the F9 22,000kg to LEO, 8,300kg to GTO is there less of a need for the FH?  These performance numbers overlap all but the highest performance numbers for the Atlas-V.  Which gives the F9 a fairly wide range of payloads it can accommodate because if necessary the legs can be removed from the F9 and it can operate in fully expendable mode for maximum performance.  The F9 with it's performance of 22,000kg to LEO now meets the definition of a HLLV. 

No, because F9 does not fly in the expended mode.  it takes CTO approval for any such mission.

But the F9 could fly in expendable mode if a mission required it? 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: ugordan on 05/25/2016 02:52 pm
"almost-FUBAR'd" is a gross overstatement. 

Perhaps, but I felt someone ought to curb the (almost rampant) optimism here to the effect of "the stage is fine, dude". Why should Jim have all the fun?

And clearly the CTO is more interested in making changes to the LV to improve its recovery and reuse characteristics, rather than throwing in the towel and just launching a high percentage of future F9 missions fully expendable.

They tried recovering v1.0s with parachutes. Didn't work out, so they gave up on it. What says that the GTO profiles near the recovery limit will result in recovered boosters that can be cost-efficiently refurbished? For all we know, they could end up being like Shuttle SRBs.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/25/2016 02:52 pm
With the recent acknowledged performance of the F9 22,000kg to LEO, 8,300kg to GTO is there less of a need for the FH?  These performance numbers overlap all but the highest performance numbers for the Atlas-V.  Which gives the F9 a fairly wide range of payloads it can accommodate because if necessary the legs can be removed from the F9 and it can operate in fully expendable mode for maximum performance.  The F9 with it's performance of 22,000kg to LEO now meets the definition of a HLLV. 

No, because F9 does not fly in the expended mode.  it takes CTO approval for any such mission.

But the F9 could fly in expendable mode if a mission required it?

Once FH is operating, what is that mission?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Brovane on 05/25/2016 02:59 pm

Once FH is operating, what is that mission?

USAF solicits proposal in the next 12-months for a Communication satellite to be launched in 2019, requirements are 7~ tons to GTO.  Does SpaceX not bid because the FH is not EELV certified yet our does SpaceX bid the F9 in expendable mode?  With the F9v1.1 those performance numbers were beyond the capability of the LV.  Now with the F9 those performance numbers are not beyond the capability of the F9 LV. 

Can we also assume that the center booster core of a FH can be recovered with a great degree of certainty and be re-used?  If the answer is no or maybe for missions that the expendable envelop of the F9 overlap with the recoverable envelop of the FH it might make sense to just bid the F9 in expendable mode.  You don't have the expense of dealing with 3 booster cores for launch (just one) and don't have to deal with the expenses of trying to recovery 3 cores and re-use them.   
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Brovane on 05/25/2016 03:01 pm
"almost-FUBAR'd" is a gross overstatement. 

Perhaps, but I felt someone ought to curb the (almost rampant) optimism here to the effect of "the stage is fine, dude". Why should Jim have all the fun?

And clearly the CTO is more interested in making changes to the LV to improve its recovery and reuse characteristics, rather than throwing in the towel and just launching a high percentage of future F9 missions fully expendable.

They tried recovering v1.0s with parachutes. Didn't work out, so they gave up on it. What says that the GTO profiles near the recovery limit will result in recovered boosters that can be cost-efficiently refurbished? For all we know, they could end up being like Shuttle SRBs.

Will the center booster stage of the FH be even under greater stress during a attempted recovery than the current F9 recovery for GTO missions? 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gongora on 05/25/2016 03:05 pm
With the recent acknowledged performance of the F9 22,000kg to LEO, 8,300kg to GTO is there less of a need for the FH?  These performance numbers overlap all but the highest performance numbers for the Atlas-V.  Which gives the F9 a fairly wide range of payloads it can accommodate because if necessary the legs can be removed from the F9 and it can operate in fully expendable mode for maximum performance.  The F9 with it's performance of 22,000kg to LEO now meets the definition of a HLLV. 

No, because F9 does not fly in the expended mode.  it takes CTO approval for any such mission.

But the F9 could fly in expendable mode if a mission required it?

I've been wondering if they could have launched Viasat 2 on F9v1.2 expendable.  Either they couldn't or they didn't want to, because the mission switched to a different launcher.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Wolfram66 on 05/25/2016 03:11 pm
Falcon heavy is reuse dependent. They likely want to relaunch and get landing a little more settled before launching FH. Remember Elon's message that they want to try to recover cores on their first flight?

They need to build additional pads. We have heard they cannot even begin building them before July because of some birds nesting season.
Question is: IF VAB flights get RTLS approval from USAF/EPA, will JRTI be moved back to Port Canaveral for CCAFS/KSC & Falcon Heavy demo for landing more than one core at sea/RTLS. ... " FH Timeline isn't retreating, it's just advancing in reverse" #Snarkasm  >:( :o :P :'( :-X
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 05/25/2016 04:17 pm
For all we know, they could end up being like Shuttle SRBs.
If you want to talk science fiction, I think there's probably a better forum for that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MattMason on 05/25/2016 04:52 pm
"almost-FUBAR'd" is a gross overstatement. 

Perhaps, but I felt someone ought to curb the (almost rampant) optimism here to the effect of "the stage is fine, dude". Why should Jim have all the fun?

And clearly the CTO is more interested in making changes to the LV to improve its recovery and reuse characteristics, rather than throwing in the towel and just launching a high percentage of future F9 missions fully expendable.

They tried recovering v1.0s with parachutes. Didn't work out, so they gave up on it. What says that the GTO profiles near the recovery limit will result in recovered boosters that can be cost-efficiently refurbished? For all we know, they could end up being like Shuttle SRBs.

Will the center booster stage of the FH be even under greater stress during a attempted recovery than the current F9 recovery for GTO missions?

That's my understanding, and why "hot" landings like JCSAT were important to try. The FH center stage will have longer downrange distance and delta-V, even with my primitive understanding of orbital mechanics.

Also, depending on the mission, it may need to use more of its fuel to complete it, such as GTO or even GSO payloads. So RTLS is out for the center, and ASDS hot-landings are probable. Else, they return the side boosters and splash the core.

The JCSAT stage only needed some barbecue dry-rub, a keg of beer and it was ready to serve--it was very charred, but still made it back. So whatever SpaceX is chewing on to make the stages more thermally protected in hot landings, the FH center core (if not all the booster cores) will need that change.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/25/2016 04:53 pm

Once FH is operating, what is that mission?

USAF solicits proposal in the next 12-months for a Communication satellite to be launched in 2019, requirements are 7~ tons to GTO.  Does SpaceX not bid because the FH is not EELV certified yet our does SpaceX bid the F9 in expendable mode?  With the F9v1.1 those performance numbers were beyond the capability of the LV.  Now with the F9 those performance numbers are not beyond the capability of the F9 LV. 

Can we also assume that the center booster core of a FH can be recovered with a great degree of certainty and be re-used?  If the answer is no or maybe for missions that the expendable envelop of the F9 overlap with the recoverable envelop of the FH it might make sense to just bid the F9 in expendable mode.  You don't have the expense of dealing with 3 booster cores for launch (just one) and don't have to deal with the expenses of trying to recovery 3 cores and re-use them.   

This makes sense... the USAF could take years to allow a reused booster for one of their payloads and remain willing to pay the cost of a new F9.  On the GPS-III bid, for instance, SpaceX sent in two proposals -- one could have been for a formerly-flown launch vehicle.

So yes, the customer could specify F9 expendable rather than the payload itself dictating not using a reusable FH.

One note:  If the customer does not specify single (new) core for this payload -- expendable implied -- would SpaceX even bid an F9 after the FH was certified?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/25/2016 05:49 pm
One note:  If the customer does not specify single (new) core for this payload -- expendable implied -- would SpaceX even bid an F9 after the FH was certified?

Do we know if reusing a FH will be cheaper than flying an expendable F9?

I don't think we know enough yet.

Plus the risks of more engines, separation events and recovery of 3 cores are also factors to consider.  If they lose the FH central core attempting a ASDS landing that alone will be more than an F9.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: bstrong on 05/25/2016 05:53 pm
That's my understanding, and why "hot" landings like JCSAT were important to try. The FH center stage will have longer downrange distance and delta-V, even with my primitive understanding of orbital mechanics.

It will likely also have substantially more propellant available for the reentry burn, so I don't know that it's a given that the landing will actually be as hot as JCSAT (for most payloads, at least).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/25/2016 06:45 pm
"almost-FUBAR'd" is a gross overstatement. 

Perhaps, but I felt someone ought to curb the (almost rampant) optimism here to the effect of "the stage is fine, dude". Why should Jim have all the fun?

And clearly the CTO is more interested in making changes to the LV to improve its recovery and reuse characteristics, rather than throwing in the towel and just launching a high percentage of future F9 missions fully expendable.

They tried recovering v1.0s with parachutes. Didn't work out, so they gave up on it. What says that the GTO profiles near the recovery limit will result in recovered boosters that can be cost-efficiently refurbished? For all we know, they could end up being like Shuttle SRBs.

Since they are exploring the 'recovery limit' in parameter space, suspect that they will set it at limits where refurb is a minor cost.  All numbers (e.g., 5500kg F9 $63M, 8000kg FH $90M) are established based on their engineering analysis and are subject to change as landings inform that analysis.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/25/2016 06:49 pm
One note:  If the customer does not specify single (new) core for this payload -- expendable implied -- would SpaceX even bid an F9 after the FH was certified?

Do we know if reusing a FH will be cheaper than flying an expendable F9?

I don't think we know enough yet.

Plus the risks of more engines, separation events and recovery of 3 cores are also factors to consider.  If they lose the FH central core attempting a ASDS landing that alone will be more than an F9.

I believe we have heard that this is true. (At least as a prediction by SpaceX.)

Makes sense... if 30% reduction is also realized for FH reused cores as forecast by GS for F9, then 7-8 tonne payloads could be priced at $63M or so (70% of $90M) which is essentially the F9 price for 5.5 tonne payloads where core is (barely) returnable and a new core is flown.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/25/2016 07:11 pm
That's my understanding, and why "hot" landings like JCSAT were important to try. The FH center stage will have longer downrange distance and delta-V, even with my primitive understanding of orbital mechanics.

It will likely also have substantially more propellant available for the reentry burn, so I don't know that it's a given that the landing will actually be as hot as JCSAT (for most payloads, at least).

For light loads like the 7-8 tonne gap loads, FH should easily have propellant available to RTLS all three cores.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomTX on 05/25/2016 07:43 pm
39A didn't look ready for FH as of last week, since the old RSS still looks darn intact. Hope to get another view/pic tomorrow.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: PahTo on 05/25/2016 07:48 pm
39A didn't look ready for FH as of last week, since the old RSS still looks darn intact. Hope to get another view/pic tomorrow.

I don't think FH is dependent upon anything to do with RSS presence.  More to do with pad infrastructure like fuel lines, dewars and the like, especially on the FSS.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 05/25/2016 08:35 pm
For all we know, they could end up being like Shuttle SRBs.
If you want to talk science fiction, I think there's probably a better forum for that.
Eh? While I don't agree that such an outcome[1] is likely, it's not out of the realm of possibility...   I think it's far more likely that they will get reuse marginal costs all in (ASDS, recovery ops, replacement parts, rewashing, etc) to 10% or less of stage costs. But that's just me.

Saying that the costs might look like SRB costs isn't science fiction, IMHO.

1 - that the cost to refurbish and use again is close to the same cost as building a new one and throwing it away, maybe a bit less maybe a bit more depending on whose numbers you believe...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MattMason on 05/25/2016 08:38 pm
That's my understanding, and why "hot" landings like JCSAT were important to try. The FH center stage will have longer downrange distance and delta-V, even with my primitive understanding of orbital mechanics.

It will likely also have substantially more propellant available for the reentry burn, so I don't know that it's a given that the landing will actually be as hot as JCSAT (for most payloads, at least).

You're likely right. Jim schooled me indirectly in a related thread on how the FH core would throttle back to conserve fuel and let the sides do the bulk of the lifting to make the center core work more like a second stage. That still puts the stack loooooong downrange, so it may have quite a bit of fuel in reserve, depending on the mission, but that core has to find an ASDS might be closer to Africa than it is the Floridian shore. But I don't know the ASDS range limits, really. That's going to be quite the boostback.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/25/2016 09:03 pm
That's my understanding, and why "hot" landings like JCSAT were important to try. The FH center stage will have longer downrange distance and delta-V, even with my primitive understanding of orbital mechanics.

It will likely also have substantially more propellant available for the reentry burn, so I don't know that it's a given that the landing will actually be as hot as JCSAT (for most payloads, at least).

You're likely right. Jim schooled me indirectly in a related thread on how the FH core would throttle back to conserve fuel and let the sides do the bulk of the lifting to make the center core work more like a second stage. That still puts the stack loooooong downrange, so it may have quite a bit of fuel in reserve, depending on the mission, but that core has to find an ASDS might be closer to Africa than it is the Floridian shore. But I don't know the ASDS range limits, really. That's going to be quite the boostback.

Isn't the bulk of the propellant used dedicated to cancelling downrange velocity and only a small fraction for the actual lob back to launch site?  If this is so, the actual downrange distance can vary by a great deal without changing the boost-back penalty significantly.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: bstrong on 05/25/2016 09:07 pm
You're likely right. Jim schooled me indirectly in a related thread on how the FH core would throttle back to conserve fuel and let the sides do the bulk of the lifting to make the center core work more like a second stage. That still puts the stack loooooong downrange, so it may have quite a bit of fuel in reserve, depending on the mission, but that core has to find an ASDS might be closer to Africa than it is the Floridian shore. But I don't know the ASDS range limits, really. That's going to be quite the boostback.

IIRC, the numbers discussed for downrange distance of the center core have been in the ballpark of 1000 miles (about a quarter of the way to Africa). But I'm assuming that if you didn't need the full performance, you'd fly a profile that wouldn't put the core that far downrange.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 05/26/2016 08:22 am
"almost-FUBAR'd" is a gross overstatement. 

Perhaps, but I felt someone ought to curb the (almost rampant) optimism here to the effect of "the stage is fine, dude". Why should Jim have all the fun?

And clearly the CTO is more interested in making changes to the LV to improve its recovery and reuse characteristics, rather than throwing in the towel and just launching a high percentage of future F9 missions fully expendable.

They tried recovering v1.0s with parachutes. Didn't work out, so they gave up on it. What says that the GTO profiles near the recovery limit will result in recovered boosters that can be cost-efficiently refurbished? For all we know, they could end up being like Shuttle SRBs.

Not sure why people think it is their job to curb others optimism, but hey ho.

Note, Musk himself said that the stages recovered so far would probably be able to launch again (in his various tweets). Optimistic, perhaps.  There again, there is nothing wrong with optimism.

There is something wrong though in making statements that are contradicted by current knowledge (i.e. Musk's statements)

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: ugordan on 05/26/2016 12:35 pm
There is something wrong though in making statements that are contradicted by current knowledge (i.e. Musk's statements)

Exactly what part of my post is contradicted by "current knowledge"? I talked about cost-efficient refurbishment. Throw enough money and time into a booster and of course you'll be able to make it fly again. Of course the JCSAT-14 booster could be made to fly again, for goodness sake it managed to land itself in one piece. Doesn't mean it's going to be more worth refurbishing it if it's sufficiently damaged than just cranking out a new stage. The jury is still very much out on this so pessimism is just as fair game as optimism is. YMMV.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/26/2016 01:18 pm
There is something wrong though in making statements that are contradicted by current knowledge (i.e. Musk's statements)

Exactly what part of my post is contradicted by "current knowledge"? I talked about cost-efficient refurbishment. Throw enough money and time into a booster and of course you'll be able to make it fly again. Of course the JCSAT-14 booster could be made to fly again, for goodness sake it managed to land itself in one piece. Doesn't mean it's going to be more worth refurbishing it if it's sufficiently damaged than just cranking out a new stage. The jury is still very much out on this so pessimism is just as fair game as optimism is. YMMV.

Another data point is GS advertising 30% price reduction on a re-flown stage.  If refurbishment is not cost efficient, how is the price dropping by approximately the cost of a new first stage?  Of course it is acceptable to discount her word, too, and wait until the market starts buying at that price point.

It took others on this forum a very long time to stop saying that SpaceX prices would rise to match the going market rate...  haven't heard much of that sour note lately, have you?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 05/26/2016 01:32 pm
There is something wrong though in making statements that are contradicted by current knowledge (i.e. Musk's statements)

Exactly what part of my post is contradicted by "current knowledge"? I talked about cost-efficient refurbishment. Throw enough money and time into a booster and of course you'll be able to make it fly again. Of course the JCSAT-14 booster could be made to fly again, for goodness sake it managed to land itself in one piece. Doesn't mean it's going to be more worth refurbishing it if it's sufficiently damaged than just cranking out a new stage. The jury is still very much out on this so pessimism is just as fair game as optimism is. YMMV.

Another data point is GS advertising 30% price reduction on a re-flown stage.  If refurbishment is not cost efficient, how is the price dropping by approximately the cost of a new first stage?  Of course it is acceptable to discount her word, too, and wait until the market starts buying at that price point.

It took others on this forum a very long time to stop saying that SpaceX prices would rise to match the going market rate...  haven't heard much of that sour note lately, have you?

I think the relationship between cost and price it a little more fluid than you're implying here. SpaceX margins might be negative for a 30% reduced reflight. Margin data isn't known publicly and probably isn't known internally yet with regard to relights.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/26/2016 02:13 pm
There is something wrong though in making statements that are contradicted by current knowledge (i.e. Musk's statements)

Exactly what part of my post is contradicted by "current knowledge"? I talked about cost-efficient refurbishment. Throw enough money and time into a booster and of course you'll be able to make it fly again. Of course the JCSAT-14 booster could be made to fly again, for goodness sake it managed to land itself in one piece. Doesn't mean it's going to be more worth refurbishing it if it's sufficiently damaged than just cranking out a new stage. The jury is still very much out on this so pessimism is just as fair game as optimism is. YMMV.

Another data point is GS advertising 30% price reduction on a re-flown stage.  If refurbishment is not cost efficient, how is the price dropping by approximately the cost of a new first stage?  Of course it is acceptable to discount her word, too, and wait until the market starts buying at that price point.

It took others on this forum a very long time to stop saying that SpaceX prices would rise to match the going market rate...  haven't heard much of that sour note lately, have you?

They don't know themselves yet. 

They likely have an idea of what window they will be in for expendable missions but not for re-use.  They need reps, lots of reps. 

By the time they get to 50-100 F9 and maybe 10-20 FH then they'll know for sure what they are making and what it costs to fly (and recover).

By the time they have a solid understanding of the Falcon family they'll likely be rolling out a raptor powered vehicle (and no I'm not saying BFR).  A single stick Raptor powered vehicle that can replace the FH would be a great product and likely much cheaper to operate.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/26/2016 02:17 pm
So Shotwell doesn't know what she's talking about...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: llanitedave on 05/26/2016 02:17 pm
There is something wrong though in making statements that are contradicted by current knowledge (i.e. Musk's statements)

Exactly what part of my post is contradicted by "current knowledge"? I talked about cost-efficient refurbishment. Throw enough money and time into a booster and of course you'll be able to make it fly again. Of course the JCSAT-14 booster could be made to fly again, for goodness sake it managed to land itself in one piece. Doesn't mean it's going to be more worth refurbishing it if it's sufficiently damaged than just cranking out a new stage. The jury is still very much out on this so pessimism is just as fair game as optimism is. YMMV.

Considering that those who actually build and recover the stages, and get the first-hand looks at the components, tend towards the optimistic side, has a bit more of an impression on me than a random pessimist with no particular insight.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/26/2016 02:20 pm
So Shotwell doesn't know what she's talking about...

I'm saying as a company they don't have enough data to be precise.

They are disrupting the market, by that very nature they don't know where it settles out.

Edit: spelling
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/26/2016 02:27 pm
So Shotwell doesn't know what she's talking about...

I'm saying as a company they don't have enough data to be precise.

They are distributing the market, by that very nature they don't know where it settles out.

Actually, it isn't going to settle out...  We are discussing the near-term pricing which GS said looks to be about a 30% discount when launching on a reused F9 core.  SES is negotiating a 50% reduction for the first ride on a formerly-owned rocket, so they'll probably get a 40-50% cut.  She also said F9 prices are heading for the $5-10M range down the road.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: ugordan on 05/26/2016 02:30 pm
Considering that those who actually build and recover the stages, and get the first-hand looks at the components, tend towards the optimistic side, has a bit more of an impression on me than a random pessimist with no particular insight.

By all means feel free to believe what you want, heaven forbid I changed anyone's mind here. I was just clarifying my point and responding to supposedly statements that have no basis in reality. Optimists obviously aren't allowed to be questioned here, lest you want to immediately be accused of calling a CEO and COO outright liars. Fine, this "random pessimist" is done with this discussion. Enjoy your unicorns.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: abaddon on 05/26/2016 02:51 pm
heading for the $5-10M range down the road.
That quote was prior to SpaceX abandoning second-stage reuse on F9.  Even then it would also require fairing recovery (which is far from a reality right now) and reuse (who knows).  We can, I think, consider that quote obsolete.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/26/2016 02:55 pm
Considering that those who actually build and recover the stages, and get the first-hand looks at the components, tend towards the optimistic side, has a bit more of an impression on me than a random pessimist with no particular insight.

Are these optimistic folks the same people that said the FH would fly in 2013?

I think many of us aren't being pessimistic but reasonable.  This is very hard stuff they are doing and they are making good progress.  What looks bad is stated schedules and goals that have no basis in reality.
 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 05/26/2016 03:02 pm
Considering that those who actually build and recover the stages, and get the first-hand looks at the components, tend towards the optimistic side, has a bit more of an impression on me than a random pessimist with no particular insight.

By all means feel free to believe what you want, heaven forbid I changed anyone's mind here. I was just clarifying my point and responding to supposedly statements that have no basis in reality. Optimists obviously aren't allowed to be questioned here, lest you want to immediately be accused of calling a CEO and COO outright liars. Fine, this "random pessimist" is done with this discussion. Enjoy your unicorns.

I think the case is rested by this post, but just in case. You were being pessimistic against the available evidence.  That was the point. I have no problem with pessimism, or indeed optimism. But when you are pessimistic and directly countering the so far known information, (or indeed optimism against known information), then that's akin  to misinformation.

Points being. Musk I believe stated that at least one of the returned stages could be reflown pretty much as is. This statement by itself would tend towards only limited refurbishment being required. And limited refurb would almost certainly imply low cost. Some of the higher speed re-entry craft are likely to need more refurb, OR a redesign to take out that need.

Of course, it's overly optimistic to say that reuse is guaranteed, but on the range of No-go to Go, it appears that we are closer to Go than no-go (from evidence of returned stages, official tweets and information gathered). So optimism would seem to be a more accurate depiction of the current state.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 05/26/2016 03:05 pm
Considering that those who actually build and recover the stages, and get the first-hand looks at the components, tend towards the optimistic side, has a bit more of an impression on me than a random pessimist with no particular insight.

Are these optimistic folks the same people that said the FH would fly in 2013?

I think many of us aren't being pessimistic but reasonable.  This is very hard stuff they are doing and they are making good progress.  What looks bad is stated schedules and goals that have no basis in reality.

AIUI, the F9H schedule has always been 'approximate', (as with most boosters from any company IIRC), since that all it needs to be. TBH, you cannot compare the F9H schedule with the reuse project. Completely different beasts. Schedule slip on F9H doesn't look 'bad' to me. Just standard operating procedure for complex engineering.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/26/2016 05:28 pm
AIUI, the F9H schedule has always been 'approximate', (as with most boosters from any company IIRC), since that all it needs to be. TBH, you cannot compare the F9H schedule with the reuse project. Completely different beasts. Schedule slip on F9H doesn't look 'bad' to me. Just standard operating procedure for complex engineering.

You are clearly seeing things as you wish to see them.

Enjoy.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 05/26/2016 05:31 pm
You are clearly seeing things as you wish to see them.

Enjoy.

We all do that to some extent. IMO the delays of FH are mostly driven by economic decisions, not technical problems.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TomTX on 05/26/2016 05:45 pm
The center core travel distance was expressed as a quarter of the way to Africa.

I think it is better expressed as about the distance from Boca Chica to the Kennedy Space Center.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Herb Schaltegger on 05/26/2016 06:45 pm
The center core travel distance was expressed as a quarter of the way to Africa.

I think it is better expressed as about the distance from Boca Chica to the Kennedy Space Center.
If you're implying that FH's launched from Boca Chica will recover center cores at KSC, maybe take a look at launch trajectory ground path estimates and overflight rules before you latch onto that idea too strongly.


Sent from my iPhone using Tapatalk
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: biosehnsucht on 05/26/2016 07:17 pm
If it can reach as far as KSC, how much fuel would it take to shorten that path to land someplace on the Florida Gulf Coast instead (so it wouldn't overfly)? Though, that angle may not be great for payloads, perhaps buy some beach front property on the southern tip of Florida (still not great, but better)?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 05/26/2016 07:24 pm
Flight paths out of Boca Chica will thread the needle between the Florida Keys and Bahamas to the north and Cuba to the south, then adjust if needed to the required inclination. There is no other way to launch without overflight of populated areas, and it will be quite some time before SpaceX gets regulatory approval to do that.

The lowest-energy landing for the first stage will lie along the trajectory from Boca Chica to south of the Keys, whether it be in the Gulf, the Atlantic, or diverted to a Key.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: LouScheffer on 05/26/2016 07:27 pm
Will be interesting to see if this [desire not to use expendable mode] changes if the GTO boosters consistently end up returning almost-FUBAR'd.
It is possible (and seems likely to me) that the line between almost-FUBAR and perfectly OK might be very thin.  Suppose, for example, that there was a fire in the engine compartment.  Not something designed for, so at the very least all engines will need to be removed, inspected and re-qualified, the octoweb might be suspect, all wiring will need to be checked and probably replaced, and so on.  Basically all but FUBAR.  This, to my mind, matches both the observations and Elon's comments (Yes, it COULD be re-used.  No, it's better to use it as max-damage test piece).

But if they can fix the fire, and keep the engine compartment within previously qualified limits, then re-use might be very straightforward.  An analogy might be a plane landing short of the airport and suffering heavy damage.  Even though this particular plane was trashed, or nearly so, it is still possible that the majority of landings will suffer no damage whatsoever. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 05/26/2016 08:02 pm
...
A single stick Raptor powered vehicle that can replace the FH would be a great product and likely much cheaper to operate.

That would be equivalent to the 6m Falcon X in the (now outdated) long-term architecture published a while back. A 5.2 meter, 5 Raptor first stage would stand a little taller than Falcon Heavy and deliver a bit more payload.

I could see a 5.2m Raptor upper stage being developed for Heavy (with some upper stage recovery development), but a 5.2m Raptor booster would need a business case to make it worth stopping there on the way to BFR.

Basically, it would have to be cheaper to launch F9 and FH payloads with a fully recoverable 5.2m system than with Falcon. I don't think the complexity of Heavy (of itself) is enough of a driver to develop a simple 5.2m booster.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/26/2016 08:48 pm
A 5.2m booster is only simpler after you've designed, built, tested, reconfigured ground systems, determined transportation mechanisms, etc.  The F9/FH more than cover all near future launch requirements at a very reasonable price and performance.  What part is broken that needs fixed?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: 2552 on 05/26/2016 09:03 pm
A 5.2m booster is only simpler after you've designed, built, tested, reconfigured ground systems, determined transportation mechanisms, etc.  The F9/FH more than cover all near future launch requirements at a very reasonable price and performance.  What part is broken that needs fixed?

If SpaceX builds a 5.2m Raptor upper stage, it would break manufacturing commonality with the 1st stage. A 5.2m Raptor 1st stage to replace F9/FH 1st stages would get that back, while reducing the number of 1st stage configurations from 2 (F9 core/FH side booster and FH center core) to 1. And since it would be fully reusable, having to use a barge for initial transport to the launch site shouldn't matter, since you'd only need to do it once and not again until it needs to be refurbished at Hawthorne/McGregor after 10 to 20 flights, as opposed to once per launch if it were expendable.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 05/26/2016 09:40 pm
AIUI, the F9H schedule has always been 'approximate', (as with most boosters from any company IIRC), since that all it needs to be. TBH, you cannot compare the F9H schedule with the reuse project. Completely different beasts. Schedule slip on F9H doesn't look 'bad' to me. Just standard operating procedure for complex engineering.

You are clearly seeing things as you wish to see them.

Enjoy.

Possibly, but more importantly, I really DONT CARE when F9H launches, and unless you have a payload desperate to go on it (is there actually anyone so desparate with a payload waiting?) , I don't think anyone else should care either. I really doesn't bother me in the slightest that it's taking its time. All I want to see it is working, whenever that may be. I'm a patient man, I can wait. After all, I'm just a bystander.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MATTBLAK on 05/26/2016 09:49 pm
We/you should care - for a variety of reasons. I want them to do it right, yes - but if they don't get going soonish, some of the goodwill and hype they've built up will start to erode confidence in their ability to deliver a really big launcher. And it hasn't been 'Falcon 9 Heavy' for quite awhile now.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 05/27/2016 01:37 am
A 5.2m booster is only simpler after you've designed, built, tested, reconfigured ground systems, determined transportation mechanisms, etc.  The F9/FH more than cover all near future launch requirements at a very reasonable price and performance.  What part is broken that needs fixed?

Marginal price and spiral development. For FH they will be building/assembling/testing 27 engines instead of potentially just 5 engines, and 3 cores instead of 1 core. And a 5.2m booster would have common tooling and engines to a 5.2m US, which would have better payloads and still have margins to develop reusability and be a major step towards BFR.

Of course, they might decide to incrementally improve the F9 S1 until BFR is flying, or make a short-stick BFR like F5 was supposed to be compared to F9.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: The Amazing Catstronaut on 05/27/2016 03:55 am
AIUI, the F9H schedule has always been 'approximate', (as with most boosters from any company IIRC), since that all it needs to be. TBH, you cannot compare the F9H schedule with the reuse project. Completely different beasts. Schedule slip on F9H doesn't look 'bad' to me. Just standard operating procedure for complex engineering.

You are clearly seeing things as you wish to see them.

Enjoy.

There is a temptation  on the internet to run for the social equivalent of the Parthian shot, the mic drop, the launch-and-leave. I'm not admonishing you for doing it here since I end up doing it all the time - but be mindful snappy dramatic curtness doesn't help anybody learn since it doesn't solicit information.  It certainly won't convince anyone to share your viewpoint. If someone provides a counterpoint, make a point back. Analyse their statement, provide any new information you have, or perhaps attempt to rephrase given information in a manner that can be digested differently. If you feel you've said everything you want to say, don't post and tab onto another thread or pop off the forum for a while.

I believe that FH's delay is reuse dependent. Certainly they're not looking to expend FH, nor do payloads exist that would require full expenditure of FH that FH would nominally launch. Ultimately it's a highly over-capable commercial launch vehicle designed to dominate the transition between partial reuse and full reuse. That's its niche - it's the ultimate evolution of the falcon family as we know it, and the last vehicle SpaceX will ever make employing merlin engines. Thus, the design of FH has been dependent upon the design evolution of F9, which current knowledge would indicate has not yet reached the end of its evolutionary cycle. F9 is the consummate commercial lift vehicle, designed with the twin aims of being made progressively more reliable, progressively more capable, and progressively cheaper. The second aim has been the case for a matter of years, the first, a matter of months, the last has yet to be proven but is directly enabled by the success of the former two.

FH takes the partial recovery system - which has only recently been proven to work at all and will likely still send innumerable stages into the Atlantic, and amplifies the operational difficulties threefold if you consider the number of cores. More if you deliberate on the re-entry strains the centre core will experience upon barge return. At maximum recoverable performance, that core will be experiencing stresses in excess of what was recently experienced during landing following JCSAT-14 - and they need to be sure they can recover cores from such trajectories consistently and with confidence. This means figuring out where the rocket needs more tps, where it needs less. Where legs need to be improved to prevent locking failure. Where grid fins (to use a historical example) need to be added to provide additional landing control. How much fuel the attitude control thrusters need. How much fuel the stage itself needs. How do we recover fairings? How to rebuild the landing legs to serve as airbrakes? How much refurbishment is needed to the stage? How many times can we refire the engines before they require part replacement? How hard can we overclock the engines? What data do we need that we lack? What structural members are going to fail? How big are the thrusters we need to put on the barge? Can we use more engines during the initial part of the landing burn to decelerate harder and yet still retain a nominal touchdown? Can we build a new stage two to enable full reuse? Can our rocket double in performance over its lifespan? How do we tweak the margins?


Not all of these questions need to be answered, or have been answered, before Falcon Heavy flies. But people have a tendency with Musk's projects (and no, I'm not giving him all the credit, but the core method is shared between them), to see the future end goal, which he's transparent about, and the present initial phases, and feel skeptical about everything in between because the target future and real world present feel so far removed from each other, or, they believe  the end goal should happen sooner than expected because they miss some aspect or another as to why the end goal is required at all. Falcon Heavy could have happened years ago if it was merely an evolution of Falcon 9.  But it isn't. It's an evolution of the F9 methodology, and F9 is the testing ground upon which that method will be proven or disproven. Above everything, it's a shift. It uses the commercial launch lineage SpaceX has developed to give them a bridge into their future, aspirational line of work in BEO. It uses the same hardware to reach the same headspace BFR will eventually occupy - reusable heavy lift, capable of launching not just significant but groundbreaking mass numbers to the Martian surface (or the moon if you really prefer, but that's not their stated goal).

FH can happily miss the boat on a few early adopters who wanted to launch on her this or last year - those early adopters will have booked alternative rides - they'll still get to space. Such is common with new launch vehicles and it's actually rather remarkable FH has attracted the pre-launch attention that it has.

Remember, everything SpaceX does is a leap of faith followed by a series of rapid adjustments to tweak that faith into a working product. F1 was a proof-of-concept that  commercial newspace could be something other than Conestoga-esque dissolution and a series of paradigm altering subscale projects. F1 was proof new players could build launch hardware that worked sufficiently to attract commercial and government money, without any real major aerospace resources on hand with just off-the-shelf, often non space rated hardware and a few extremely talented and quite possibly slightly mad engineers. Period. It was proof that private launch startups could exist. It also permitted them to figure out the basic processes required to cobble elementary rockets together and send them hobbling into space, if barely and inconsistently. Once F1s started tick the basic boxes of: 1) it doesn't explode every time, and 2) we can occasionally get it to the pad without tearing it to pieces in transit, it was no longer required. In a slightly differently contracted universe, SpaceX could have gone on to have beat rocketlabs and firefly to the punch. Instead, we got F9. We were going to get F5, which was ambitious enough: a roughly soyuz class LV dwarfing anything they'd done before, but the overall vision required F9. F9 was an extrapolation of all of F1's targets - cheap commercial launch - except this time it had to be comprehensively useful, both to NASA and the commercial market. Ignoring Dragon and everything that represents (this is the FH thread after all), F9's evolutionary process is similar to F1. They're still trying to figure out what they can do better in house, they're still trying to figure out how to make their propulsion technology better, they're still trying to figure out how to lower the costs of access to space, they're still trying to figure out how to get to mars - except F9 had to be physically capable of all of these requirements instead of merely indicating a possible future. The journey to reuse has turned a fairly gawky looking, mediocre performing LV into what might shake out to be one of the best workhorse LV ever and certainly one of the most iconic, right up there with Semyorka, Redstone, the Atlas and Titan lines, Soyuz, Proton, STS and the Saturn line. It is a Soyuz with the ability to out-Soyuz Soyuz. VTVL reuse is revolutionary and -might- achieve what STS never did for significantly less investment. FH has to do all of that whilst juggling, and (for a brief period of time), being the highest performance LV in operation.  It is a beast that is going to launch with 27 engines ignited roughly simultaneously. It is also a beast that is predicated upon the expectation that every ethos F9 is built upon is correct - and that is not the case yet. Until F9 has been finessed to the point where F9 can have high ground and flight reliability, can be reused and reflown with confidence and a full spectrum of data has been acquired as to the nature of what various re-entry paths require, FH is not going to be as great a rocket as it potentially could be.

I'd go as far as saying every month they delay FH gives them another 6 weeks where FH will remain at the top of its game - because every launch F9 makes is a lesson which feeds directly into FH. This process will continue when both rockets are flying in tandem - doubtless they will learn from each other, but they will keep tackling perceived deficiencies until they come up stumped. Indeed, considering that they've only been landing for a few months, I'm sure there's a plethora of changes they've had to add to FH considering the influx of fresh data they must have received. The presence of actual reuse data will be evolving FH significantly - so it should be.

There is still a hard deadline: 2018. They'll want a few flights in before then. But I'm not concerned. The postponement lengths are starting to decrease all the time and have been for the last two years. A one month delay is immaterial, with the possible exception for christmas festivities.

Edits: Spelling, grammar and literacy. In defence of the poster, I'm currently living on a diet of caffeine tablets and insomnia so things may have slipped the net.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 05/27/2016 08:10 am
We/you should care - for a variety of reasons. I want them to do it right, yes - but if they don't get going soonish, some of the goodwill and hype they've built up will start to erode confidence in their ability to deliver a really big launcher. And it hasn't been 'Falcon 9 Heavy' for quite awhile now.

But will that goodwill disappear? Will confidence erode? I don't see why. They are doing something no-one has done before. Everyone in this industry knows how difficult it is, everyone knows there is always slippage. Everyone also knows that the work they are doing on F9 reuse directly influences how the FH will work and how cheap it will be. Everyone knows that they had a 6 month hiatus while they sorted out the 'issue', everyone knows they are working hard on Dragon2, and everyone knows that as a launch provider they are getting better and better.

Given all that, would people in the industry really lose goodwill, or confidence because of a 'delay'? I don't think so.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MATTBLAK on 05/27/2016 08:33 am
Stranger things happen. Maybe Space Geeks are relatively patient, but Joe Public isn't - and they bore easily. Now; you may think that doesn't matter but I'm betting it does. We'll see. F.H. will be flying soon-ish.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 05/27/2016 01:03 pm
Stranger things happen. Maybe Space Geeks are relatively patient, but Joe Public isn't - and they bore easily. Now; you may think that doesn't matter but I'm betting it does. We'll see. F.H. will be flying soon-ish.

What has Joe Public got to do with it?

We are not important, Joe Public isn't important, but the people who want to use FH, they are important. And perhaps, the only important ones. And they are the people who understand what is going on. They don't get bored.

SpaceX does not rely on public opinion.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: philw1776 on 05/27/2016 01:09 pm
Most recently since late 2015 the "real soon now" FH 1st flight schedule announcements have been way off. 
Late 2015 it slipped out of that year again to early 2016, maybe April. 
Then as we turned the corner of the year and approached within several months of launch date it moved to NET September 2016. 
Once again when within 4 months or so of launch it slipped yet again to NET December 2016. 

I think 2 factors are pushing this rightward in time:
(1) ongoing learning about recovered cores forcing design improvements that would make FH more economical
(2) SX economics and capacity focused 1st on meeting the aggressive launch cadence increase Shotwell mentioned
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/27/2016 01:25 pm
We/you should care - for a variety of reasons. I want them to do it right, yes - but if they don't get going soonish, some of the goodwill and hype they've built up will start to erode confidence in their ability to deliver a really big launcher. And it hasn't been 'Falcon 9 Heavy' for quite awhile now.

To put the FH timeline into perspective, a super heavy lift vehicle (in its various incarnations) has been on the drawing boards and getting tax dollars since SpaceX was formed; it still hasn't flown.  Less than a decade ago, SpaceX was proud owner of three small vehicle launch failures in a row and completely broke.  The first F9, a medium class, expendable (aren't weren't they all?) vehicle successfully flew six years ago next week.  A first stage successfully landed propulsively for the first in history five months ago.  F9 now is classified as a heavy lift vehicle, is certified for USAF/NASA payloads, and has the title as the most efficient launch vehicle ever flown, beating out Energia, DIVH, and Saturn V in the process.

On that basis, a new super heavy vehicle, Falcon (Super) Heavy, will launch within the year -- or so. ;)  It will have half the thrust of the other SHLV being built, but deliver equivalent payload at a small fraction of the price.  When all that capability isn't needed for the several currently manifested payloads, it will fly in a reusable mode where all three of it's cores will propulsively land back at the launch site or on a friggin' barge somewhere downrange.

Loss of goodwill and erosion of confidence are likely if there was nothing to show for the delays (not to mention the costs -- oh wait, the taxpayers weren't billed for this one) in building a SHLV. 

Doesn't seem to be the case -- for FH at least.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MATTBLAK on 05/27/2016 01:32 pm
Stranger things happen. Maybe Space Geeks are relatively patient, but Joe Public isn't - and they bore easily. Now; you may think that doesn't matter but I'm betting it does. We'll see. F.H. will be flying soon-ish.

What has Joe Public got to do with it?

We are not important, Joe Public isn't important, but the people who want to use FH, they are important. And perhaps, the only important ones. And they are the people who understand what is going on. They don't get bored.

SpaceX does not rely on public opinion.


Look; I'm not looking for an argument, really?! How about we lighten up some and move on... But even if I accept your fatalism/negativity - and I partly do - they have a very large fan base on social media and their main event launches stream to very large numbers over the net. Nothing more, nothing less! And some of those people have/are going to buy Teslas etc. It's important if you take it in context. (anyone wanna help me out here? No..?) That's about all the explainin' I can manage now at 1:30am (my time) over and out... ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cuddihy on 05/27/2016 01:39 pm
Flight paths out of Boca Chica will thread the needle between the Florida Keys and Bahamas to the north and Cuba to the south, then adjust if needed to the required inclination. There is no other way to launch without overflight of populated areas, and it will be quite some time before SpaceX gets regulatory approval to do that.

The lowest-energy landing for the first stage will lie along the trajectory from Boca Chica to south of the Keys, whether it be in the Gulf, the Atlantic, or diverted to a Key.

I prefer launch Boca Chica, TX, downrange landing Boca Chica Key, FL 😀.

I'm sure the Navy would be happy to provide some space on the unused side of the runway.
https://en.m.wikipedia.org/wiki/Boca_Chica_Key
It does lie right on the flight path.

Unfortunately, I believe ballistic trajectory would be a few hundred miles short, so you'd actually have to boost forward to get there...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 05/27/2016 02:41 pm
SpaceX does not rely on public opinion.

I think I disagree with that. Musk is a showman and his companies deliver PR spectacles. Also, as this article points out, there is a growing buzz and interest in launches.

http://www.smh.com.au/business/innovation/elon-musks-spacex-livestream-is-his-most-surprising-success-20160526-gp4zm4.html

It may not be outpacing the Kardashians but it matters.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/27/2016 03:03 pm
great article*

*fluff piece for you steely-eyed rocket engineers
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/27/2016 04:12 pm
SpaceX does not rely on public opinion.

I think I disagree with that. Musk is a showman and his companies deliver PR spectacles. Also, as this article points out, there is a growing buzz and interest in launches.

http://www.smh.com.au/business/innovation/elon-musks-spacex-livestream-is-his-most-surprising-success-20160526-gp4zm4.html

It may not be outpacing the K*************s but it matters.

I thought there was an unspoken rule that the K word was not to used on NSF?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: chrisking0997 on 05/27/2016 05:21 pm
Stranger things happen. Maybe Space Geeks are relatively patient, but Joe Public isn't - and they bore easily. Now; you may think that doesn't matter but I'm betting it does. We'll see. F.H. will be flying soon-ish.

What has Joe Public got to do with it?

We are not important, Joe Public isn't important, but the people who want to use FH, they are important. And perhaps, the only important ones. And they are the people who understand what is going on. They don't get bored.

SpaceX does not rely on public opinion.


Look; I'm not looking for an argument, really?! How about we lighten up some and move on... But even if I accept your fatalism/negativity - and I partly do - they have a very large fan base on social media and their main event launches stream to very large numbers over the net. Nothing more, nothing less! And some of those people have/are going to buy Teslas etc. It's important if you take it in context. (anyone wanna help me out here? No..?) That's about all the explainin' I can manage now at 1:30am (my time) over and out... ;)

agreed.  some may think it does not matter, but it does.  How many years have we heard how spaceflight and exploration will not garner an increase in funding due to the fact that the public by and large do not really care about it?  And now suddenly we have SpaceX on the scene, accomplishing very public milestones on their vision of going to Mars, opening up the potential of lower costs and more missions, and exciting the public at least to the level of the Shuttle era...and now what the public thinks is not important?  Maybe not in the small picture of the industry, but it most certainly matters in the big picture.  Im not sure that the FH delay will cause a loss of interest, but its something to consider.  I have a suspicion SpaceX will keep us interested for the immediate future.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/27/2016 06:56 pm
Stranger things happen. Maybe Space Geeks are relatively patient, but Joe Public isn't - and they bore easily. Now; you may think that doesn't matter but I'm betting it does. We'll see. F.H. will be flying soon-ish.

What has Joe Public got to do with it?

We are not important, Joe Public isn't important, but the people who want to use FH, they are important. And perhaps, the only important ones. And they are the people who understand what is going on. They don't get bored.

SpaceX does not rely on public opinion.


Look; I'm not looking for an argument, really?! How about we lighten up some and move on... But even if I accept your fatalism/negativity - and I partly do - they have a very large fan base on social media and their main event launches stream to very large numbers over the net. Nothing more, nothing less! And some of those people have/are going to buy Teslas etc. It's important if you take it in context. (anyone wanna help me out here? No..?) That's about all the explainin' I can manage now at 1:30am (my time) over and out... ;)

MATTBLAK,
You are right on the money when you say public opinion does matter...  Engineer-wise, it is one of those unquantifiable factors that tend to be dismissed as unimportant (IMO, precisely because they are difficult to quantify).  I watched the commercial nuclear industry go down the toilet (1980s) because public concern about the danger of nuclear anything was poo-poo'd by the nuclear engineering leaders in the industry.  "Just trust us, we know what we're doing" was their refrain... 

So far, SpaceX is riding high in public opinion and it does matter. 
That good will/brand recognition needs to be preserved -- but I don't think it is at all endangered by another FH schedule slip.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 05/27/2016 07:23 pm
You need goodwill to attract top talent. Without top talent, you can't have a SpaceX.

Ergo, SpaceX can't slow down and remain SpaceX.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MattMason on 05/27/2016 08:17 pm
You need goodwill to attract top talent. Without top talent, you can't have a SpaceX.

Ergo, SpaceX can't slow down and remain SpaceX.

So long as that not-slowing-down does not create a privatized form of "Go Fever," I agree.

A launch slip is one thing. Tragedy is another--but thankfully, SpaceX has shown caution, and FH isn't flying people anytime soon.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 05/27/2016 08:30 pm
What if Go-fever is the only way to make progress? If you want to make an omelette...

...but in all seriousness, there are ways to be incredibly risky, incredibly aggressive without killing people, and that's by testing everything very thoroughly uncrewed first and by having well-tested abort capabilities.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: StuffOfInterest on 05/28/2016 01:34 pm
How about a little discussion of Falcon Heavy engineering instead of politics for a change.

Something I noticed in the animations for the Falcon Heavy flight.  After the side boosters detach the top mounts between cores stay attached to the center core and then fold down.  Any theory on how much weight these add and how much of a performance penalty is being accepted to keep them on the center core instead of dropping them?  I can see why they wouldn't be kept on the side core, it would leave the core unbalanced with the mount hanging on one side.  It doesn't seem like these mounts would be an overly expensive item, so I'm curious if there is that much of a penalty to keep them.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MATTBLAK on 05/28/2016 02:08 pm
I suppose that only after the first FH is flown, we may know/they will release a full table of comparison parameters for the payload performances in different recovery modes?

Full Expendable/Crossfeed - 54 metric tons or better.
Core Expended - boosters flyback to KSC, Core Expended - boosters land on Drone ships, all first stages land at KSC, all stages land on Drone ships... That sort of thing.

And some of us have speculated an upper stage upgrade via a wider 5.2 meter stage and LOX/CH4 propellants and new engine. But what about merely stretching the upper stage another 10% percent or so and uprating the Merlin 1D 'Full Thrust' even more - would that be an easier path to FH upgrades than a complete Upper Stage redesign? Would this result in a launcher that's 'too tall'? That darn Falcon 9 F.T. is one long, skinny thing already...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/28/2016 03:44 pm
Although I believe they could benefit from a stretched-again second stage, I suspect that the next step is second stage reuse... and higher energy payloads like inter-planetary.  That could be better accomplished with a methlox stage and (mini-)Raptor.  Before 'improving' the FH, fly it a bit and see if essentials need to change, especially involving the three core configuration.

When need begins to exist for the full payload capability (direct insertion of USAF payloads, propellant deliveries, inter-planetary flights, etc.), the methlox second stage (probably 5-ish meters) will enter the scene -- IMO around 2018.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 05/28/2016 04:45 pm
Although I believe they could benefit from a stretched-again second stage, I suspect that the next step is second stage reuse... and higher energy payloads like inter-planetary.  That could be better accomplished with a methlox stage and (mini-)Raptor.  Before 'improving' the FH, fly it a bit and see if essentials need to change, especially involving the three core configuration.

When need begins to exist for the full payload capability (direct insertion of USAF payloads, propellant deliveries, inter-planetary flights, etc.), the methlox second stage (probably 5-ish meters) will enter the scene -- IMO around 2018.

Not sure that the FH needs improved performance at this time.  The only benefit they really out of the better second stage is improving recovery profile of the center core.

A minor stretch of the current second stage would mean having 2 versions of a stage and that goes against SpaceX behavior, up to now anyway.

A Raptor upper stage, although exciting in theory, with a 4.8 meter diameter engine nozzle that is going to be some amazing interstage.  Plus doubling the weight of the stage you'll end up with a structurally revised S1 anyway. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 05/28/2016 05:12 pm
Although I believe they could benefit from a stretched-again second stage, I suspect that the next step is second stage reuse... and higher energy payloads like inter-planetary.  That could be better accomplished with a methlox stage and (mini-)Raptor.  Before 'improving' the FH, fly it a bit and see if essentials need to change, especially involving the three core configuration.

When need begins to exist for the full payload capability (direct insertion of USAF payloads, propellant deliveries, inter-planetary flights, etc.), the methlox second stage (probably 5-ish meters) will enter the scene -- IMO around 2018.

Not sure that the FH needs improved performance at this time.  The only benefit they really out of the better second stage is improving recovery profile of the center core.

A minor stretch of the current second stage would mean having 2 versions of a stage and that goes against SpaceX behavior, up to now anyway.

A Raptor upper stage, although exciting in theory, with a 4.8 meter diameter engine nozzle that is going to be some amazing interstage.  Plus doubling the weight of the stage you'll end up with a structurally revised S1 anyway.
Doubling the weight of the upper stage without increasing thrust of the core stage wouldn't necessarily change the structure of the first stage that much because the peak acceleration would be much lower. They could also throttle-down the core stage to reduce loads, at least for the first flights.

...but I think they'd be willing to make such changes to the core stage eventually. I don't think that's a show-stopper at all.


I'm still on the fence about the Raptor stage. I'm fairly certain there's some key information they're not telling us, information that may even be embargoed by the space press. So I really can't say either way if they're actually planning on it, though I'm leaning towards "yes."

EDIT: I think it's plausible that they have been substantially paused on Raptor/BFR work after CRS7. They may have had to catch their breath. This may have caused a change in plans, too. I guess we'll find out in September.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: the_other_Doug on 05/28/2016 07:27 pm
I'm thinking that one of the most reliable Omens and Portents that the first FH launch is actually going to happen within a few months will be the construction of a second RTLS landing pad at CCAFS, either adjacent to the existing LC-1 (within the same rented footprint), or at a different location elsewhere on the Cape (perhaps another old, decommissioned pad complex).

I don't believe SpaceX is ever going to bring JRtI back to Florida, and I also don't believe they will launch any FH without the intention of recovering at least the booster cores, if not all three cores.

So, the landing resource math says that, for each FH launch, in order to recover three cores, you need either three ASDSes, two ASDSes and one RTLS landing pad, or (far most likely) one ASDS and two RTLS landing pads.

Ergo, we'll either need to see at least one more ASDS built and deployed, or another RTLS landing pad built, prior to the first FH launch.  And as I say, the sign I'd be looking for would be the construction of that second landing pad...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 05/28/2016 07:45 pm
They need at least two more pads. I am convinced that a not insignificant part of FH flights will RTLS the central core.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 05/28/2016 11:22 pm
FH will need extra performance, a different upper stage, and core booster changes anyway, in order to begin testing upper stage recovery for MCT. The MCT upper stage is going to be very expensive to test like F9 first stages... throwing them away won't be appealing.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Prettz on 05/29/2016 05:19 am
FH will need extra performance, a different upper stage, and core booster changes anyway, in order to begin testing upper stage recovery for MCT. The MCT upper stage is going to be very expensive to test like F9 first stages... throwing them away won't be appealing.
Why does FH need a new upper stage to test something related to MCT?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 05/29/2016 05:43 am
Why does FH need a new upper stage to test something related to MCT?

BFR/MCT will use the Raptor methane engine. MCT also will do return from orbit. A new raptor based upper stage for FalconHeavy will help testing both in an operational environment at much lower cost than building MCT.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Prettz on 05/29/2016 03:33 pm
Why does FH need a new upper stage to test something related to MCT?

BFR/MCT will use the Raptor methane engine. MCT also will do return from orbit. A new raptor based upper stage for FalconHeavy will help testing both in an operational environment at much lower cost than building MCT.
Or you can put a payload on FH to test this.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 05/29/2016 05:03 pm
BFR/MCT will use the Raptor methane engine. MCT also will do return from orbit. A new raptor based upper stage for FalconHeavy will help testing both in an operational environment at much lower cost than building MCT.
Or you can put a payload on FH to test this.

They could. But doing a reusable upper stage is so much modus operandi by SpaceX. Testflights again paid for by customers. They are also contracted by the Airforce to develop a Raptor engine suitable for such a stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Roy_H on 05/29/2016 05:36 pm
I don't believe they will ever land the two boosters on ASDSs,  but all will be RTLS. No expendable side boosters either. RTLS of the center core is possible, but the performance penalty is so much that this will be  relegated to intermediate loads just too large for F9. So I believe most center cores will land on ASDS. If returning all 3 cores to landing site is done, cross-feed would be impractical, so if they do build cross-feed versions then I believe these center cores will all land on the ASDS.  Of course there is the possibility of expending the center core. That reduces the number of variations to 4.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Prettz on 05/29/2016 07:26 pm
They could. But doing a reusable upper stage is so much modus operandi by SpaceX.
A new stage and new engine and new interstage, plus new TEL and ground equipment for methane, all limited in use to some small minority of FH launches? I think you've got that backwards.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 05/29/2016 07:33 pm
They could. But doing a reusable upper stage is so much modus operandi by SpaceX.
A new stage and new engine and new interstage, plus new TEL and ground equipment for methane, all limited in use to some small minority of FH launches? I think you've got that backwards.
Small minority of launches?? If it happens, it'd eventually be used for all FH launches, and probably all F9 launches as well (the air force document says the Raptor upper stage would be used for both FH and F9).

Or perhaps you think they'll just make the jump to BFR all in one go. That's far-fetched to me. Not impossible, but unlikely. They need a "Falcon 1" for Raptor.

A new TEL is no big deal. They've probably built like nearly a dozen different TELs so far. I remember at first, they almost built a new one each launch! New engine they are already building and are under contract to build. And they had no quibbles about building new ground support equipment to enable the extra performance boost of subcooling the propellants.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 05/29/2016 08:01 pm
Suggest that any Raptor activity is geared to BFR futures/need, not FH. If on a FH US, primarily as a means to gather flight history for advancing BFR/Raptor programs.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Prettz on 05/29/2016 08:04 pm
Small minority of launches?? If it happens, it'd eventually be used for all FH launches, and probably all F9 launches as well (the air force document says the Raptor upper stage would be used for both FH and F9).
I guess I misunderstood, then. If they outright replace the second stage for all Falcon launches that would be more believable. I'd still be shocked if they did. A different diameter stage is the opposite from how they've done things thus far.

Quote
Or perhaps you think they'll just make the jump to BFR all in one go. That's far-fetched to me. Not impossible, but unlikely. They need a "Falcon 1" for Raptor.
No they definitely wouldn't do it all in one go. I would more imagine a Grasshopper for Raptor and BFR.

And for testing MCT reentry, a whole new upperstage for Falcon is just not needed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GreenShrike on 05/29/2016 08:43 pm
I don't believe they will ever land the two boosters on ASDSs,  but all will be RTLS.

Probably. Per Nadrek's and others' calculations, side cores to ASDS provides little in the way of additional performance.

No expendable side boosters either.

It would certainly be an expensive FH flight, but expending the sides gets you around +30% (from 8t to 11t) to Mars. I'd say probably a 'final flight' type mission for cores on the verge of retirement, but then I can't help but think that you'd not want to risk that large a Mars mission on cores you want to retire.

RTLS of the center core is possible, but the performance penalty is so much that this will be relegated to intermediate loads just too large for F9.

Of which there are few. Only flagship comsats are 6t+, and they're the only ones F9-R can't launch -- but FH 3-RTLS can.

So I believe most center cores will land on ASDS.

FH 3-RTLS can put 7t+ into GTO (8t if SpaceX's $90M for up to to that mass implies 3-RTLS), which is more than the largest comsat. As such, with current payloads it's a rare bird that will require more from FH (i.e. central core ASDS or expended).

Beyond 3-RTLS lay the large NSS payloads (i.e. DIVH flights) and interplanetary missions.

If returning all 3 cores to landing site is done, cross-feed would be impractical, so if they do build cross-feed versions then I believe these center cores will all land on the ASDS.

I wouldn't consider a changing a long boost-back burn into a somewhat longer boost-back burn to be "impractical". It's really just more of the same.

In essence, crossfeed and RTLS are orthogonal issues. Crossfeed basically improves FH's performance for any given mission, so a CF FH can get a payload to an orbit with less prop used than the same flight in a non-CF configuration. As the crossfed FH will have spent far less prop lifting the side cores before they separate, additional prop in the center will thence be available. Some of this excess prop can be used to boost a bigger payload and the rest to null out the higher resulting center core velocity and RTLS.

Nadrek calculates ~9t to GTO with a CF FH 3-RTLS flight, which is a healthy -- though unnecessary, hence the lack of CF development -- boost over a non-CF FH 3-RTLS mission.

CF http://forum.nasaspaceflight.com/index.php?topic=39181.msg1521480#msg1521480
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/29/2016 08:51 pm
They could. But doing a reusable upper stage is so much modus operandi by SpaceX.
A new stage and new engine and new interstage, plus new TEL and ground equipment for methane, all limited in use to some small minority of FH launches? I think you've got that backwards.

If you limit your thinking to commercial and USG markets, then you have a point. 
But FH is not being built merely for those markets.

GS has discussed using the FH for a large number of Mars preparation missions.  A Raptor second stage would be perfect for these high energy missions and also the opportunity to test MCT at sub-scale (only 20-30 tonne payloads landing on Mars).  Also, if when fuel depots are deployed, they will be liquid methane and oxygen, so a methlox tanker would be required -- powered by a Raptor, I'd assume.

In the same way that they've waited for the F9 technology to be proven/stable before flying FH on their own dime, BFR/MCT will use FH to prepare the ground for it's arrival.  Raptor, in-space refueling, Mars EDL with large payloads, Earth EDL, etc. will all be proven before BFR uses them.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GreenShrike on 05/29/2016 08:56 pm
Small minority of launches?? If it happens, it'd eventually be used for all FH launches, and probably all F9 launches as well (the air force document says the Raptor upper stage would be used for both FH and F9).
I guess I misunderstood, then. If they outright replace the second stage for all Falcon launches that would be more believable. I'd still be shocked if they did. A different diameter stage is the opposite from how they've done things thus far.

Recovering the upper stage is also "opposite from how they've done things thus far."

And if SpaceX is recovering the Raptor upper stages, then it matters a fair bit less if they're more expensive to construct. Rock bottom cost is rather more important for expendable stages.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/29/2016 08:57 pm
I don't believe they will ever land the two boosters on ASDSs,  but all will be RTLS.

Probably. Per Nadrek's and others' calculations, side cores to ASDS provides little in the way of additional performance.

No expendable side boosters either.

It would certainly be an expensive FH flight, but expending the sides gets you around +30% (from 8t to 11t) to Mars. I'd say probably a 'final flight' type mission for cores on the verge of retirement, but then I can't help but think that you'd not want to risk that large a Mars mission on cores you want to retire.
<snip>

Both 8 and 11 tonnes are too small by an order of magnitude for SpaceX plans. 
In-space refueling is required to enter the big time Mars game.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 05/29/2016 09:52 pm
In the same way that they've waited for the F9 technology to be proven/stable before flying FH on their own dime, BFR/MCT will use FH to prepare the ground for it's arrival.  Raptor, in-space refueling, Mars EDL with large payloads, Earth EDL, etc. will all be proven before BFR uses them.

Correct. The stage recovery effort right now is an example of a capability gained. Irrespective of reflight of booster, it adds to, for example, Mars return. In that one can see how a MAV, itself a tall stage plus capsule, can be landed on Mars. These capabilities are links in the chain to assembling a credible program for Mars. RD, in doing a propulsive landing on Mars, also provides a means for a LAS recovery of a MAV capsule on launch failure.

And in the Musk style, you get these capabilities to "pay for themselves" after a fashion. Stage recovery is "paid for" by excess margin overhang. The additional benefit is in stage reuse.

So likewise propulsive Dragon landing.

A Raptor US gets you:
 a) flight history
 b) potential recovery/reuse
 c) high C3 missions
 d) long duration, high performance US
 e) potential Mars environment use (LMO, landing/ascent)
... so you can prove your propulsion in like missions before you commit to a BFR with people on it landing.

Same goes for all you list. Also, think of the multiple ways these can be used as in exploration architectures.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GreenShrike on 05/29/2016 11:09 pm
Both 8 and 11 tonnes are too small by an order of magnitude for SpaceX plans. 
In-space refueling is required to enter the big time Mars game.

Well, of course. Baby steps first, though -- assuming Red Dragon counts as "baby". ;-)

Think they'll try refueling a Merlin second stage?  They may have a Raptor upper stage available come the 2020 window, so they might skip developing Merlin-based refueling hardware.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/29/2016 11:30 pm
Both 8 and 11 tonnes are too small by an order of magnitude for SpaceX plans. 
In-space refueling is required to enter the big time Mars game.

Well, of course. Baby steps first, though -- assuming Red Dragon counts as "baby". ;-)

Think they'll try refueling a Merlin second stage?  They may have a Raptor upper stage available come the 2020 window, so they might skip developing Merlin-based refueling hardware.

I don't think Kerlox fits well into refueling technology... it pretty much is a dead end.  Refueling and depots are best when high energy departures are involved.  Fuels are thus limited to hydrogen, methane, oxygen in their liquid forms, of course -- there may be others, but these seem to be leading candidates.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rpapo on 05/29/2016 11:51 pm
I don't think Kerlox fits well into refueling technology... it pretty much is a dead end.  Refueling and depots are best when high energy departures are involved.  Fuels are thus limited to hydrogen, methane, oxygen in their liquid forms, of course -- there may be others, but these seem to be leading candidates.
While I agree with you regarding Kerolox, I really wonder just how difficult it will be to retain liquid oxygen, hydrogen or methane for long periods of time, even or especially in orbit.  Long periods, in this case, means more than a couple of days, and in fact probably months.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AncientU on 05/30/2016 12:34 am
I don't think Kerlox fits well into refueling technology... it pretty much is a dead end.  Refueling and depots are best when high energy departures are involved.  Fuels are thus limited to hydrogen, methane, oxygen in their liquid forms, of course -- there may be others, but these seem to be leading candidates.
While I agree with you regarding Kerolox, I really wonder just how difficult it will be to retain liquid oxygen, hydrogen or methane for long periods of time, even or especially in orbit.  Long periods, in this case, means more than a couple of days, and in fact probably months.

Methlox is discussed as a natural zero boil-off propellant for depots.  Hydrogen (liquid) is a deep cryogen and significantly more technically challenging.  Trips to/from Mars will need indefinite storage of the chosen propellant as will depots.  Actually, LEO is one of the most challenging environments due to Solar and Earth both being heat sources.  Deeper space, even cis-Lunar or EML-1/2 are much simpler because the Sun becomes the single radiant point source and is easily shielded.

Since we're drifting well off topic and there are so many good depot discussions, we should leave it there.  Here's a thread with a mere 51 pages of discussion on that topic.
http://forum.nasaspaceflight.com/index.php?topic=12338.0
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Torten on 06/02/2016 06:47 pm
I'm quite aware that you can't treat rockets like Lego, but would it be possible to add two more Falcon 9 cores to the Falcon Heavy to provide for some extra payload without having to make any massive modifetions to the core stage?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 06/02/2016 06:58 pm
I'm quite aware that you can't treat rockets like Lego, but would it be possible to add two more Falcon 9 cores to the Falcon Heavy to provide for some extra payload without having to make any massive modifetions to the core stage?

How is it going to be assembled with the current infrastructure?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MattMason on 06/02/2016 07:02 pm
I'm quite aware that you can't treat rockets like Lego, but would it be possible to add two more Falcon 9 cores to the Falcon Heavy to provide for some extra payload without having to make any massive modifetions to the core stage?

How is it going to be assembled with the current infrastructure?

If I read Jim right, he's noting that the Falcon is horizontally assembled. To try to add a third or more cores means a wholly different way of assembly that SpaceX doesn't do without leasing space in the VAB. Won't happen.

I don't want to even think of the engineering logistics needed to manage more than the 27 engines on a normal FH.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/02/2016 07:16 pm
I'm quite aware that you can't treat rockets like Lego, but would it be possible to add two more Falcon 9 cores to the Falcon Heavy to provide for some extra payload without having to make any massive modifetions to the core stage?

If you're looking for capacity improvement (for non-existing payloads) then develop crossfeed and a Raptor US.

Although a 5.4 meter (or larger) Raptor US will require significant lad mods itself.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cscott on 06/02/2016 07:22 pm
I'm thinking that one of the most reliable Omens and Portents that the first FH launch is actually going to happen within a few months will be the construction of a second RTLS landing pad at CCAFS, either adjacent to the existing LC-1 (within the same rented footprint), or at a different location elsewhere on the Cape (perhaps another old, decommissioned pad complex).

I don't believe SpaceX is ever going to bring JRtI back to Florida, and I also don't believe they will launch any FH without the intention of recovering at least the booster cores, if not all three cores.

So, the landing resource math says that, for each FH launch, in order to recover three cores, you need either three ASDSes, two ASDSes and one RTLS landing pad, or (far most likely) one ASDS and two RTLS landing pads.

Ergo, we'll either need to see at least one more ASDS built and deployed, or another RTLS landing pad built, prior to the first FH launch.  And as I say, the sign I'd be looking for would be the construction of that second landing pad...
Scrub Jay nesting season ends June 30.  Expect to see your "omen and portent" shortly afterward.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kansan52 on 06/02/2016 07:36 pm
I'm quite aware that you can't treat rockets like Lego, but would it be possible to add two more Falcon 9 cores to the Falcon Heavy to provide for some extra payload without having to make any massive modifetions to the core stage?

I would say 'No'. It would require enough changes to the center core to make such a project violate the SX 'KISS' style. And it would require massive changes to the pad like flame trench, GSE, TEL, ect.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/02/2016 08:41 pm
I'm quite aware that you can't treat rockets like Lego, but would it be possible to add two more Falcon 9 cores to the Falcon Heavy to provide for some extra payload without having to make any massive modifetions to the core stage?

I would say 'No'. It would require enough changes to the center core to make such a project violate the SX 'KISS' style. And it would require massive changes to the pad like flame trench, GSE, TEL, ect.

In addition to all this, the boost stage of the Falcon Heavy is already rather overpowered, and adding 2 more boosters would make it absurdly overpowered, relative to the current upper stage. Since the center core isn't vacuum optimized, it's a waste to put it in space almost fully fueled... and it makes the center core that much more difficult to recover since it's going higher, faster and further downrange.

The cost benefit calculus points to improving the upper stage first, then getting a bigger booster.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 06/03/2016 01:14 pm
I'm quite aware that you can't treat rockets like Lego, but would it be possible to add two more Falcon 9 cores to the Falcon Heavy to provide for some extra payload without having to make any massive modifetions to the core stage?

How is it going to be assembled with the current infrastructure?

If I read Jim right, he's noting that the Falcon is horizontally assembled. To try to add a third or more cores means a wholly different way of assembly that SpaceX doesn't do without leasing space in the VAB. Won't happen.

I don't want to even think of the engineering logistics needed to manage more than the 27 engines on a normal FH.
It can be horizontally integrated. Just look up how Energia Buran was integrated. It would require a new TEL design, and I'm not sure it would fit the LC-40 flame trench. And it would need a new center core. That could launch with as little as 3 engines. But then the question is why if they rather develop the MCT.
Oh! And I guess it would really complicate the lower interfaces and hold downs. But with a lot of extra work and cost it could be done horizontally. Probably not cost effective, though.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rpapo on 06/03/2016 01:34 pm
It can be horizontally integrated. Just look up how Energia Buran was integrated. It would require a new TEL design, and I'm not sure it would fit the LC-40 flame trench. And it would need a new center core. That could launch with as little as 3 engines. But then the question is why if they rather develop the MCT.
Oh! And I guess it would really complicate the lower interfaces and hold downs. But with a lot of extra work and cost it could be done horizontally. Probably not cost effective, though.
Having five cores with the current design would be problematic, above and beyond all the reasons already given.  You really do want liftoff with every engine in play, as that is when your gravity losses are highest.  But after that it comes down to just how much you can throttle down the engines you want to conserve fuel for later.  I don't think you would want to actually shut them down entirely.  And if they are throttled to the minimum (40-50%% or so), they are still consuming half as much fuel as normally.

Bottom line: Instead of having what is effectively 2.5 stages, you might wind up with effectively 2.75 stages, at best.  At a cost roughly 60% higher than the three core design.  Diminishing returns.

Theoretically, cross-feed would help, but how much?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: AC in NC on 06/03/2016 02:57 pm
In addition to all this, the boost stage of the Falcon Heavy is already rather overpowered, and adding 2 more boosters would make it absurdly overpowered, relative to the current upper stage.

Key being ... relative to the current upper stage.

[amazing people fantasy warning]

The 5-wide speculation leads down this path:

You design the modular 5-wide system with cross-feed, an interstage that permits all cores to support the upperstage, and you Lego-up 25-cores that orbit a 20m diameter upperstage.

[/amazing people fantasy warning]

Elon wants to travel in comfort.   
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rpapo on 06/03/2016 03:32 pm
Elon wants to travel in comfort.
Lots of Gs ain't my idea of comfort...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TrueBlueWitt on 06/03/2016 03:44 pm
Just put a wrapper around them. And raptor on each core.. Shades of Saturn-1b
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Torten on 06/03/2016 06:31 pm
That's interesting. So the best way to increase the payload of the Falcon Heavy is a bigger upper stage. If such a need existed, I would guess space X would choose to stretch the second stage, and add two more vaccum Merlins to the stage. Easier than integating a second fuel type into the launch infrastructure to allow for the use of the Raptor engine.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: nadreck on 06/03/2016 06:35 pm
That's interesting. So the best way to increase the payload of the Falcon Heavy is a bigger upper stage. If such a need existed, I would guess space X would choose to stretch the second stage, and add two more vaccum Merlins to the stage. Easier than integating a second fuel type into the launch infrastructure to allow for the use of the Raptor engine.
No need to add an engine, the Merlin has plenty of thrust for a larger upper stage, especially if that stage is only used with the FH so it will be further along than the current F9 upper stage is at ignition.

The reason to go Raptor is to get improved ISP and more balanced fuel/oxidizer temperatures (which may make long life easier without adding extra mass).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/03/2016 06:55 pm
That's interesting. So the best way to increase the payload of the Falcon Heavy is a bigger upper stage. If such a need existed, I would guess space X would choose to stretch the second stage, and add two more vaccum Merlins to the stage. Easier than integating a second fuel type into the launch infrastructure to allow for the use of the Raptor engine.
No need to add an engine, the Merlin has plenty of thrust for a larger upper stage, especially if that stage is only used with the FH so it will be further along than the current F9 upper stage is at ignition.

The reason to go Raptor is to get improved ISP and more balanced fuel/oxidizer temperatures (which may make long life easier without adding extra mass).

Plus the Merlin Vacuum engine is gigantic, there is no way to fit 3 of them on any remotely Falcon-sized stage. You'd need a 8m diameter interstage at minimum.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 06/04/2016 07:28 am
To re-iterate that point.

(http://i.imgur.com/FRszulq.png)

MVac pushes 95 tonnes. By the time the fuel runs out, the engine has to throttle below 40% so as to not kill the payload with high g-forces.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/04/2016 02:36 pm
To re-iterate that point.

(http://i.imgur.com/FRszulq.png)

MVac pushes 95 tonnes. By the time the fuel runs out, the engine has to throttle below 40% so as to not kill the payload with high g-forces.

Just imagine the Raptor-Vac (on top of a F9 or FH).

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 06/04/2016 09:03 pm
The usual T/W of a second stage is usually between 1 and 1/2. So they could increase a bit the US fuel mass without requiring an increased thrust US.
What I have just realized, is that since SpaceX is designing for reusability, the first stage separates at a lower velocity and thus, the US should have a great T/W because they will be fighting gravity a lot more than a Centaur, for comparing to something.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/05/2016 11:21 pm
The usual T/W of a second stage is usually between 1 and 1/2. So they could increase a bit the US fuel mass without requiring an increased thrust US.
What I have just realized, is that since SpaceX is designing for reusability, the first stage separates at a lower velocity and thus, the US should have a great T/W because they will be fighting gravity a lot more than a Centaur, for comparing to something.

Given SpaceX's history and business practices, they took the engine they had and made the vehicle parameters fit.

As long as the US engine can throttle low enough to not overload the stage and payload why not go for it?

It's a good way to build an affordable vehicle.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 06/07/2016 02:40 pm
Has it been noticed that the SpaceX website now shows direct GEO insertion as a capability of Falcon Heavy?

http://www.spacex.com/falcon-heavy

Quote
Falcon Heavy draws upon Falcon 9’s proven design, which minimizes stage separation events and maximizes reliability. The second-stage Merlin engine, identical to its counterpart on Falcon 9, delivers the rocket’s payload to orbit after the main engines cut off and the first-stage cores separate. The engine can be restarted multiple times to place payloads into a variety of orbits including low Earth, geosynchronous transfer orbit (GTO) and  geosynchronous orbit (GSO).

Bold mine.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/07/2016 03:12 pm
Just imagine the Raptor-Vac (on top of a F9 or FH).

I don't know that the Raptor Vac will be enormously bigger (at least any version of it flying on Falcon) since there are diminishing returns. A 40% bigger bell can handle 2x the thrust with the same expansion ratio.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/07/2016 03:17 pm
Has it been noticed that the SpaceX website now shows direct GEO insertion as a capability of Falcon Heavy?

http://www.spacex.com/falcon-heavy

Quote
Falcon Heavy draws upon Falcon 9’s proven design, which minimizes stage separation events and maximizes reliability. The second-stage Merlin engine, identical to its counterpart on Falcon 9, delivers the rocket’s payload to orbit after the main engines cut off and the first-stage cores separate. The engine can be restarted multiple times to place payloads into a variety of orbits including low Earth, geosynchronous transfer orbit (GTO) and  geosynchronous orbit (GSO).

Bold mine.

I believe that is a requirement for defense payloads. 

Maybe that will be the FH demo mission.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/07/2016 03:41 pm
Just imagine the Raptor-Vac (on top of a F9 or FH).

I don't know that the Raptor Vac will be enormously bigger (at least any version of it flying on Falcon) since there are diminishing returns. A 40% bigger bell can handle 2x the thrust with the same expansion ratio.

The number that was discussed for the nozzle was 4.8 meter diameter.  The ripple affects of that is what I find interesting.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/07/2016 05:17 pm
Just imagine the Raptor-Vac (on top of a F9 or FH).

I don't know that the Raptor Vac will be enormously bigger (at least any version of it flying on Falcon) since there are diminishing returns. A 40% bigger bell can handle 2x the thrust with the same expansion ratio.

The number that was discussed for the nozzle was 4.8 meter diameter.  The ripple affects of that is what I find interesting.

I believe 4.8m was calculated using the 230 tonne sea level thrust and 380s vacuum ISP figures from the rettid AMA. Anything flying on Falcon will probably be an early version... so I'd expect a lower thrust and maybe a lower expansion ratio. I just don't see any feasible way to fly a 4.8m nozzle on Falcon.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 06/07/2016 06:07 pm
Just imagine the Raptor-Vac (on top of a F9 or FH).

I don't know that the Raptor Vac will be enormously bigger (at least any version of it flying on Falcon) since there are diminishing returns. A 40% bigger bell can handle 2x the thrust with the same expansion ratio.

The number that was discussed for the nozzle was 4.8 meter diameter.  The ripple affects of that is what I find interesting.

I believe 4.8m was calculated using the 230 tonne sea level thrust and 380s vacuum ISP figures from the rettid AMA. Anything flying on Falcon will probably be an early version... so I'd expect a lower thrust and maybe a lower expansion ratio. I just don't see any feasible way to fly a 4.8m nozzle on Falcon.
The feasible way is to have a wider upper stage and interstage. And possibly an extending nozzle like RL-10B2 and like shown in this SpaceX video at 1:13: https://www.youtube.com/watch?v=sSF81yjVbJE
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 06/07/2016 06:19 pm
The feasible way is to have a wider upper stage and interstage.
This probably is what they will do if they go wider. But I think it will take some careful thought, since the widest part of the nozzle is at the bottom. And the bottom is where the narrowest part of the interstage would be, since that is where it starts flaring out... so there may need to be a gap of some size to get it to work.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/07/2016 07:17 pm
The feasible way is to have a wider upper stage and interstage.
This probably is what they will do if they go wider. But I think it will take some careful thought, since the widest part of the nozzle is at the bottom. And the bottom is where the narrowest part of the interstage would be, since that is where it starts flaring out... so there may need to be a gap of some size to get it to work.

Remember that the current upper stage is putting over 500 tonnes of force on the interstage at burnout and max-Q, and the load path for that force has to go around the outside of the bell, not through the nozzle bell... so even if it's retractable, it still has to fit inside the interstage with clearance. A wide Raptor stage will double that load.

The current interstage is 47% wider than the MVac bell, 3.67 m vs. 2.5 m. I don't know exactly how close they are willing to get to the interstage walls before the chance of recontact during separation is unacceptable, but a 4.8 m bell will probably not clear a 5.2 m interstage that's only 8% bigger. A 6 m interstage is 25% bigger, but does about the same .6 m clearance as the MVac.

6 m is a pretty big for a 3.67 m booster that's already really tall and skinny. It might fly on Falcon Heavy where fineness isn't as big a problem, but I really doubt that ever flies on F9... and the Air Force contract indicates that Raptor will be designed for both F9 and Heavy.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 06/07/2016 08:05 pm
How much ISP would Raptor lose when it has a nozzle diameter of only 4m?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 06/07/2016 08:06 pm
The feasible way is to have a wider upper stage and interstage.
This probably is what they will do if they go wider. But I think it will take some careful thought, since the widest part of the nozzle is at the bottom. And the bottom is where the narrowest part of the interstage would be, since that is where it starts flaring out... so there may need to be a gap of some size to get it to work.
...or have an extendible nozzle like the part that you trimmed from my post.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: catdlr on 06/07/2016 08:31 pm
SpaceX - Falcon Heavy - 39A Update 06-06-2016

USLaunchReport

Published on Jun 7, 2016
We noticed some big changes from a few months ago, especially under the tent and above. We are getting much closer to Falcon Heavy.

https://youtu.be/3-6-aDbVqvM?t=001

https://youtu.be/3-6-aDbVqvM

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/07/2016 08:43 pm
The feasible way is to have a wider upper stage and interstage.
This probably is what they will do if they go wider. But I think it will take some careful thought, since the widest part of the nozzle is at the bottom. And the bottom is where the narrowest part of the interstage would be, since that is where it starts flaring out... so there may need to be a gap of some size to get it to work.
...or have an extendible nozzle like the part that you trimmed from my post.

The last bit of the conversation is great.

Extendible nozzle helps with interstage length, doesn't nothing for width. 

A 4.8 meter nozzle is 4.8 meters whether in 1, 2 or more pieces.  As we've seen from on board footage the separation events are not that smooth.

A rocket with a 500,000 lbf upper stage is going to need good clearances and some creative problem solving.

Of course maybe there is a smaller Raptor in the works and this discussion changes.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 06/07/2016 08:46 pm
The feasible way is to have a wider upper stage and interstage.
This probably is what they will do if they go wider. But I think it will take some careful thought, since the widest part of the nozzle is at the bottom. And the bottom is where the narrowest part of the interstage would be, since that is where it starts flaring out... so there may need to be a gap of some size to get it to work.
...or have an extendible nozzle like the part that you trimmed from my post.

I was addressing width. I thought extendable nozzles only help with length (ala collapsible cups). Has anyone deployed a nozzle that's narrower and fans out to a larger diameter?

I trim stuff when I don't think it's relevant to what I'm saying.

As a note I went to the WP article on extendable nozzles... very weak. The RL10 article sadly doesn't say how that nozzle extends
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/07/2016 08:48 pm
How much ISP would Raptor lose when it has a nozzle diameter of only 4m?
Does it have to make the same thrust as the 4.8m nozzle? Because ISP isn't solely dictated by nozzle size - for the same fuels it is a function of pressure ratios... and there are other ways to change pressure ratios (e.g. change mass flow and/or throat diameter) at the expense of thrust.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 06/07/2016 09:01 pm
How much ISP would Raptor lose when it has a nozzle diameter of only 4m?
Does it have to make the same thrust as the 4.8m nozzle? Because ISP isn't solely dictated by nozzle size - for the same fuels it is a function of pressure ratios... and there are other ways to change pressure ratios (e.g. change mass flow and/or throat diameter) at the expense of thrust.

Obviously I don't even know enough to ask the right question. For arguments sake assume the same engine, just a smaller nozzle.

Though what we know does not rule out that a dedicated smaller version of Raptor might be built.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/08/2016 01:29 pm
How much ISP would Raptor lose when it has a nozzle diameter of only 4m?
Does it have to make the same thrust as the 4.8m nozzle? Because ISP isn't solely dictated by nozzle size - for the same fuels it is a function of pressure ratios... and there are other ways to change pressure ratios (e.g. change mass flow and/or throat diameter) at the expense of thrust.

Obviously I don't even know enough to ask the right question. For arguments sake assume the same engine, just a smaller nozzle.

Though what we know does not rule out that a dedicated smaller version of Raptor might be built.
Raptor with a 4 m nozzle loses about 1% of ISP compared to a 4.8 m nozzle: 376 s vs 380 s.

This is based on sim in RPA lite using: Methane/LOX at:
9.7 MPa chamber pressure (same as Merlin)
2.8 O/F ratio (optimum for methalox at 9.7 MPa)
165 expansion ratio for the 4.8 m nozzle (same as Merlin Vac)
115 expansion ratio for the 4 m nozzle (assuming same throat diameter as the 4.8 m nozzle)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 06/08/2016 03:59 pm
Raptor with a 4 m nozzle loses about 1% of ISP compared to a 4.8 m nozzle: 376 s vs 380 s.

Thanks a lot.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GreenShrike on 06/08/2016 05:08 pm
And possibly an extending nozzle like RL-10B2.

I believe that on the Delta IVs an RL-10B2 nozzle extension failure results in LoM.

If a Raptor upper stage is designed to be reusable and, thus, would not fly itself dry before releasing its payload, do you think that an extension failure could be adequately compensated for by burning de-orbit/recovery propellant?

If so, it would fit with SpaceX's theme of being able to sacrifice recovery to ensure mission success.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/08/2016 06:55 pm
How much ISP would Raptor lose when it has a nozzle diameter of only 4m?
Does it have to make the same thrust as the 4.8m nozzle? Because ISP isn't solely dictated by nozzle size - for the same fuels it is a function of pressure ratios... and there are other ways to change pressure ratios (e.g. change mass flow and/or throat diameter) at the expense of thrust.

Obviously I don't even know enough to ask the right question. For arguments sake assume the same engine, just a smaller nozzle.

Though what we know does not rule out that a dedicated smaller version of Raptor might be built.
Raptor with a 4 m nozzle loses about 1% of ISP compared to a 4.8 m nozzle: 376 s vs 380 s.

This is based on sim in RPA lite using: Methane/LOX at:
9.7 MPa chamber pressure (same as Merlin)
2.8 O/F ratio (optimum for methalox at 9.7 MPa)
165 expansion ratio for the 4.8 m nozzle (same as Merlin Vac)
115 expansion ratio for the 4 m nozzle (assuming same throat diameter as the 4.8 m nozzle)

Nice work, but that's a lot of assumptions.

What thrust do you get?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 06/08/2016 07:03 pm
And possibly an extending nozzle like RL-10B2.

I believe that on the Delta IVs an RL-10B2 nozzle extension failure results in LoM.
Depends on the mission. Also, I don't think it has ever failed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/08/2016 07:23 pm
How much ISP would Raptor lose when it has a nozzle diameter of only 4m?
Does it have to make the same thrust as the 4.8m nozzle? Because ISP isn't solely dictated by nozzle size - for the same fuels it is a function of pressure ratios... and there are other ways to change pressure ratios (e.g. change mass flow and/or throat diameter) at the expense of thrust.

Obviously I don't even know enough to ask the right question. For arguments sake assume the same engine, just a smaller nozzle.

Though what we know does not rule out that a dedicated smaller version of Raptor might be built.
Raptor with a 4 m nozzle loses about 1% of ISP compared to a 4.8 m nozzle: 376 s vs 380 s.

This is based on sim in RPA lite using: Methane/LOX at:
9.7 MPa chamber pressure (same as Merlin)
2.8 O/F ratio (optimum for methalox at 9.7 MPa)
165 expansion ratio for the 4.8 m nozzle (same as Merlin Vac)
115 expansion ratio for the 4 m nozzle (assuming same throat diameter as the 4.8 m nozzle)

Nice work, but that's a lot of assumptions.

What thrust do you get?

2097 kN for the 4.0 m nozzle
2119 kN for the 4.8 m nozzle, about 1% more, which corresponds to the 1% ISP increase.

Since the thrust and ISP come out almost exactly where Musk was projecting, my assumptions probably aren't all that far off. Either chamber pressure or throat area (or both) might be little low.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/08/2016 08:34 pm
2097 kN for the 4.0 m nozzle
2119 kN for the 4.8 m nozzle, about 1% more, which corresponds to the 1% ISP increase.

Since the thrust and ISP come out almost exactly where Musk was projecting, my assumptions probably aren't all that far off. Either chamber pressure or throat area (or both) might be little low.

Cool thanks.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: hkultala on 06/08/2016 08:42 pm

Raptor with a 4 m nozzle loses about 1% of ISP compared to a 4.8 m nozzle: 376 s vs 380 s.

This is based on sim in RPA lite using: Methane/LOX at:
9.7 MPa chamber pressure (same as Merlin)
2.8 O/F ratio (optimum for methalox at 9.7 MPa)
165 expansion ratio for the 4.8 m nozzle (same as Merlin Vac)
115 expansion ratio for the 4 m nozzle (assuming same throat diameter as the 4.8 m nozzle)

Isn't staged combustion supposed to mean higher chamber pressure than gas generator?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/08/2016 08:51 pm

Raptor with a 4 m nozzle loses about 1% of ISP compared to a 4.8 m nozzle: 376 s vs 380 s.

This is based on sim in RPA lite using: Methane/LOX at:
9.7 MPa chamber pressure (same as Merlin)
2.8 O/F ratio (optimum for methalox at 9.7 MPa)
165 expansion ratio for the 4.8 m nozzle (same as Merlin Vac)
115 expansion ratio for the 4 m nozzle (assuming same throat diameter as the 4.8 m nozzle)

Isn't staged combustion supposed to mean higher chamber pressure than gas generator?

*full flow

Edit:
https://en.wikipedia.org/wiki/Raptor_%28rocket_engine%29
Additional characteristics of the full-flow design that are projected to further increase performance or reliability include:
-eliminating the fuel-oxidizer turbine interseal, which is a potential point of failure in more traditional engine designs
-lower pressures are required through the pumping system, increasing life span and further reducing risk of catastrophic failure
-ability to increase the combustion chamber pressure, thereby either increasing overall performance, or "by using cooler gases, providing the same performance as a standard staged combustion engine but with much less stress on materials, thus significantly reducing material fatigue or [engine] weight".
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: OnWithTheShow on 06/22/2016 08:26 pm
So nary a whisper here of the photos on other sites of the other core (engineless) outside Hawthorne with the mystery hold down fittings?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kansan52 on 06/22/2016 08:31 pm
So nary a whisper here of the photos on other sites of the other core (engineless) outside Hawthorne with the mystery hold down fittings?

There has been posts including the photos. But memory fails which subject line. Will try to locate.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/22/2016 08:38 pm
So nary a whisper here of the photos on other sites of the other core (engineless) outside Hawthorne with the mystery hold down fittings?

There has been posts including the photos. But memory fails which subject line. Will try to locate.

I've been looking for them outside of L2 as well.  To me it most certainly looks like the FH center core.

It got me thinking the biggest problem with ever developing crossfeed, if they ever wanted it would be routing piping around the folded up landing legs.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: OnWithTheShow on 06/22/2016 08:43 pm
I cant really notice any differences at first glance from a standard core but the fact that it is being wrapped for transport with no engines is what makes it unusual.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cartman on 06/22/2016 08:54 pm
Here are some of the photos i did manage to collect
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/22/2016 09:26 pm
I believe there are two different stages in these pictures.  The equipment and building around the vehicles seem different.


The top picture does not appear to be your normal F9 Octoweb. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 06/22/2016 09:32 pm
I believe there are two different stages in these pictures.  The equipment and building around the vehicles seem different.


The top picture does not appear to be your normal F9 Octoweb.

Yes, that's true. There are two stages. One is a landed stage coming back from Florida. One is quite certain to be new. It's octoweb is unlike anything seen before. That's why it is very plausible it is a FH central core.

Funny, that SpaceX puts a core on the street with the octoweb uncovered. And at a time when there are plenty of people around to take photos who came to see the used stage returning.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/22/2016 09:50 pm
Certainly something not seen before, very exciting.

The second (non FH) core looks very clean to be a returned stage.

Maybe someone with photo analysis skills and software can confirm, but I can sort of make up double tabs at the bottom of the photo as well. 

If so that would match the plan to have 2 side hold downs for the FH Center. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/22/2016 10:35 pm
Same stage in all four pictures.
Noteworthy new features on the Octaweb seeming load points (compression loads)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MrHollifield on 06/22/2016 10:47 pm
I would concur it is the same stage in all 4 photos.

Comparing the attachment and hold-down points to the returned CRS-8 stage, there appears to be a second attachment point on the new stage. Look at 12 o'clock on the new stage and 3- and 9-o'clock on the older stage below.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Arb on 06/22/2016 10:50 pm
Re the lack of engines. Three possibilities:

1) It's a structural test article / pathfinder which doesn't need them
2) Manufacturing efficiency improvement [1]
3) Another reason entirely.

[1] The current flow is build engine in Hawthorn, ship to McGregor for unit testing, back to Hawthorn for integration into an octoweb, back to McGregor for booster test and then on to launch site. However, they now have experience of removing and installing engines at all of those locations; so a more efficient flow might be build engine in Hawthorn, ship to McGregor for unit testing, ship new booster to McGregor without engines; install them there for booster test and then on to launch site.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Burninate on 06/23/2016 12:01 am

Raptor with a 4 m nozzle loses about 1% of ISP compared to a 4.8 m nozzle: 376 s vs 380 s.

This is based on sim in RPA lite using: Methane/LOX at:
9.7 MPa chamber pressure (same as Merlin)
2.8 O/F ratio (optimum for methalox at 9.7 MPa)
165 expansion ratio for the 4.8 m nozzle (same as Merlin Vac)
115 expansion ratio for the 4 m nozzle (assuming same throat diameter as the 4.8 m nozzle)

O/F ratio was supposed to be 3.8.  Chamber pressure seems like the big unknown - if the M1D gas generator produces 9.7MPa, what should we expect in a FFSC Raptor?

Musk: "The critical elements of the solution are rocket reusability and low cost propellant (CH4 and O2 at an O/F ratio of ~ 3.8 ). And, of course, making the return propellant on Mars, which has a handy CO2 atmosphere and lots of H2O frozen in the soil." - http://waitbutwhy.com/2015/08/how-and-why-spacex-will-colonize-mars.html/4
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: catdlr on 06/23/2016 12:12 am
I believe there are two different stages in these pictures.  The equipment and building around the vehicles seem different.


I would concur it is the same stage in all 4 photos.



The answer is....

source: http://imgur.com/a/q7yoL
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Burninate on 06/23/2016 12:31 am

Raptor with a 4 m nozzle loses about 1% of ISP compared to a 4.8 m nozzle: 376 s vs 380 s.

This is based on sim in RPA lite using: Methane/LOX at:
9.7 MPa chamber pressure (same as Merlin)
2.8 O/F ratio (optimum for methalox at 9.7 MPa)
165 expansion ratio for the 4.8 m nozzle (same as Merlin Vac)
115 expansion ratio for the 4 m nozzle (assuming same throat diameter as the 4.8 m nozzle)

O/F ratio was supposed to be 3.8.  Chamber pressure seems like the big unknown - if the M1D gas generator produces 9.7MPa, what should we expect in a FFSC Raptor?

Musk: "The critical elements of the solution are rocket reusability and low cost propellant (CH4 and O2 at an O/F ratio of ~ 3.8 ). And, of course, making the return propellant on Mars, which has a handy CO2 atmosphere and lots of H2O frozen in the soil." - http://waitbutwhy.com/2015/08/how-and-why-spacex-will-colonize-mars.html/4

Also:
How are real numbers likely to come in, in relation to the figures provided by RPA Lite?  Would the RPA numbers represent a theoretical maximum or perhaps a plausible best-guess at the exact values?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: OnWithTheShow on 06/23/2016 12:46 am
As seen above there were two stages parked outside. One was confirmed from photo analysis to be Orbcomm (comparison of reentry markings on the lower portion). The other features some new elements to its octaweb we havent seen before. Seems likely it is a FH side booster from the location of the new features or just an incremental improvement to existing full thrust? Be interesting to see where it ends up. I can buy into both scenarios mentioned above. They are changing the flow to do engine integration at McGregor or this is a structural test article.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/23/2016 12:57 am

Raptor with a 4 m nozzle loses about 1% of ISP compared to a 4.8 m nozzle: 376 s vs 380 s.

This is based on sim in RPA lite using: Methane/LOX at:
9.7 MPa chamber pressure (same as Merlin)
2.8 O/F ratio (optimum for methalox at 9.7 MPa)
165 expansion ratio for the 4.8 m nozzle (same as Merlin Vac)
115 expansion ratio for the 4 m nozzle (assuming same throat diameter as the 4.8 m nozzle)

O/F ratio was supposed to be 3.8.  Chamber pressure seems like the big unknown - if the M1D gas generator produces 9.7MPa, what should we expect in a FFSC Raptor?

Musk: "The critical elements of the solution are rocket reusability and low cost propellant (CH4 and O2 at an O/F ratio of ~ 3.8 ). And, of course, making the return propellant on Mars, which has a handy CO2 atmosphere and lots of H2O frozen in the soil." - http://waitbutwhy.com/2015/08/how-and-why-spacex-will-colonize-mars.html/4

Neither of those particularly affect the relative differences between the 4 meter and 4.8 meter nozzle; the benefit of having extra expansion is about the same for a higher pressure engine.

I just grabbed that 2.8:1 O/F number off a chart, and according to RPA it is actually a bit low for a 165:1 expansion vacuum engine. At 10 MPa the O/F for optimal ISP is 3.4:1, and at 15 MPa it optimizes at 3.45:1. However, 3.8:1 is rather high and actually loses a second or two of ISP (although you get a bit better thrust due to higher massflow).

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/23/2016 01:06 am
How are real numbers likely to come in, in relation to the figures provided by RPA Lite?  Would the RPA numbers represent a theoretical maximum or perhaps a plausible best-guess at the exact values?

RPA calculates both the theoretical best possible performance, and a best guess at the actual performance after accounting for combustion and nozzle inefficiencies. I have no idea how accurate it is in reality. And we don't have a ton of known parameters to put in.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 06/23/2016 02:27 am
From the O/F and the two isp points I had estimated 20.5MPa as Pc. Can't recall the expansion.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Burninate on 06/23/2016 02:42 am
The four datapoints we have are 321s (sealevel small-nozzle?) , 363s (vacuum small-nozzle?), and 380s (vacuum big-nozzle?), with an O:F ratio of 3.8.  I had 14.5MPa working for theoretical numbers ("Express thermodynamic analysis") at expansion ratios of 32.5 and 75.

Changing it to "Extended analysis" and examining chamber performance given the estimated reaction and nozzle efficiencies, I end up losing 14s off of each number.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 06/23/2016 04:00 am
I used actual vs theoretical. And modified a bit the freeze chemistry since the ch4/lox combustion, while appears simple, has a lot of steps.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Burninate on 06/23/2016 04:38 am
Punch it up to the RD-180 chamber pressure - 26.7MPa
Using the listed estimates for 3.8:1 inefficiencies rather than theoretical maxima in RPA Lite:
With an expansion ratio of 59, you get 321s at sealevel and 363s in vacuum.
With an expansion ratio of 164, you get 380s in vacuum.

Sidenote: Do we have a higher chamber pressure liquid rocket engine in existence than the RD-180?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 06/23/2016 05:01 am
Same stage in all four pictures.
Noteworthy new features on the Octaweb seeming load points (compression loads)

Yep. But you missed another new feature, which appears to be the main load bearing one for the octaweb. I have circled the three new Octaweb features (red), and overlaid a simple line drawing to indicate how I assume it will connect to the FH core (blue):
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 06/23/2016 05:17 am
I have circled the three new Octaweb features (red), and overlaid a simple line drawing to indicate how I assume it will connect to the FH core (blue):

Good explanation on the connections, thanks. However I believe this is the central core and the same connectors are on the other side not seen on this picture too. My reasoning, Gwynne Shotwell said the side boosters are the same as Falcon 9. We know with the difference of the connecting points but still basically the same. This is totally different. I don't think they have completely redone the thrust structure for all cores. Not right after Elon Musk has said the design is now mostly fixed.  :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 06/23/2016 06:05 am
I have circled the three new Octaweb features (red), and overlaid a simple line drawing to indicate how I assume it will connect to the FH core (blue):

Good explanation on the connections, thanks. However I believe this is the central core and the same connectors are on the other side not seen on this picture too. My reasoning, Gwynne Shotwell said the side boosters are the same as Falcon 9. We know with the difference of the connecting points but still basically the same. This is totally different. I don't think they have completely redone the thrust structure for all cores. Not right after Elon Musk has said the design is now mostly fixed.  :)

According to a SpaceX'er on Reddit*, the FH booster octaweb is not identical to the F9 octaweb, there are small differences (attachment points), and these could fit the bill.

But you are right, this could also be an FH core.

* source: https://www.reddit.com/r/spacex/comments/3ybhtt/what_will_fly_first_the_falcon_heavy_or_the_sls/cyciu7m
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 06/23/2016 06:11 am
I see this octoweb as not some changes. It is a whole new, completely different design. That's why I expect it to be the central core. But let's see. One day we will know for sure.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/23/2016 02:08 pm
Punch it up to the RD-180 chamber pressure - 26.7MPa
Using the listed estimates for 3.8:1 inefficiencies rather than theoretical maxima in RPA Lite:
With an expansion ratio of 59, you get 321s at sealevel and 363s in vacuum.
With an expansion ratio of 164, you get 380s in vacuum.

Sidenote: Do we have a higher chamber pressure liquid rocket engine in existence than the RD-180?

That's very interesting. Do you really think they will try to run at 26.7 MPa? For comparison, the RD-191 and RD-180 run at 26.7 MPa, and the SSME ran up to 21 MPa. I think that's the highest pressure ever flown in a reusable engine. A 100% length bell nozzle gets the same performance at 25 MPa and 55:1 expansion (155:1 for the vac nozzle).

The nice thing about higher chamber pressures is the engine gets much smaller (but not lighter) for the same thrust. At 25 MPa the SL Raptor only needs a 1.88m diameter nozzle to get Musk's estimated 500klbf of thrust, and the vac version gets 591klbf with only a 3.16m dia nozzle.

To bring this entire conversation back to Falcon Heavy (we were wandering OT for a bit there), that would mean it's possible a 25 MPa Raptor Vac could fly in the current Falcon interstage. Even with the nozzle trimmed back to 70% (which would put it very nearly in the Mvac envelope), it could realistically get 265 tonnes of thrust at 377s ISP. That's a healthy upgrade over Mvac's 95 tonnes thrust and 348 ISP.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mvpel on 06/23/2016 02:16 pm
Yep. But you missed another new feature, which appears to be the main load bearing one for the octaweb. I have circled the three new Octaweb features (red), and overlaid a simple line drawing to indicate how I assume it will connect to the FH core (blue):

This one is definitely the core - the same side-booster attachment point appears on the lower side of the booster on one of the photos above, as you can see here. I'll bet they have an attach/release mechanism that links these "buffed up" core-booster fixtures to the existing Falcon 9 hold-down design to eliminate the need for any changes in the side booster octaweb design.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: fthomassy on 06/23/2016 02:45 pm
This one is definitely the core - the same side-booster attachment point appears on the lower side of the booster on one of the photos above, as you can see here. I'll bet they have an attach/release mechanism that links these "buffed up" core-booster fixtures to the existing Falcon 9 hold-down design to eliminate the need for any changes in the side booster octaweb design.
Is it possible FH sides and core share the same web structure?  In fact, this could be a new web for all boosters if the weight penalty is acceptable.  Then you only have one web part number which has production flow advantages.

I have a sneaking suspicion one could join L2 to find out.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MKremer on 06/23/2016 03:04 pm
This one is definitely the core - the same side-booster attachment point appears on the lower side of the booster on one of the photos above, as you can see here. I'll bet they have an attach/release mechanism that links these "buffed up" core-booster fixtures to the existing Falcon 9 hold-down design to eliminate the need for any changes in the side booster octaweb design.
Is it possible FH sides and core share the same web structure?  In fact, this could be a new web for all boosters if the weight penalty is acceptable.  Then you only have one web part number which has production flow advantages.
That's a good question, though I believe SpaceX has already said the Core booster is a separate unique design.

I'm interested in seeing the top area of the booster, and see if there are some obvious changes to it for supporting the upper attachments.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 06/23/2016 03:39 pm
This one is definitely the core - the same side-booster attachment point appears on the lower side of the booster on one of the photos above, as you can see here. I'll bet they have an attach/release mechanism that links these "buffed up" core-booster fixtures to the existing Falcon 9 hold-down design to eliminate the need for any changes in the side booster octaweb design.
Is it possible FH sides and core share the same web structure?  In fact, this could be a new web for all boosters if the weight penalty is acceptable.  Then you only have one web part number which has production flow advantages.

I have a sneaking suspicion one could join L2 to find out.
3 Separate Octowebs. Similar for shared production but different for each role it plays. F9, FH Core, FH Booster.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Burninate on 06/23/2016 04:04 pm
Punch it up to the RD-180 chamber pressure - 26.7MPa
Using the listed estimates for 3.8:1 inefficiencies rather than theoretical maxima in RPA Lite:
With an expansion ratio of 59, you get 321s at sealevel and 363s in vacuum.
With an expansion ratio of 164, you get 380s in vacuum.

Sidenote: Do we have a higher chamber pressure liquid rocket engine in existence than the RD-180?

That's very interesting. Do you really think they will try to run at 26.7 MPa? For comparison, the RD-191 and RD-180 run at 26.7 MPa, and the SSME ran up to 21 MPa. I think that's the highest pressure ever flown in a reusable engine. A 100% length bell nozzle gets the same performance at 25 MPa and 55:1 expansion (155:1 for the vac nozzle).

The nice thing about higher chamber pressures is the engine gets much smaller (but not lighter) for the same thrust. At 25 MPa the SL Raptor only needs a 1.88m diameter nozzle to get Musk's estimated 500klbf of thrust, and the vac version gets 591klbf with only a 3.16m dia nozzle.

To bring this entire conversation back to Falcon Heavy (we were wandering OT for a bit there), that would mean it's possible a 25 MPa Raptor Vac could fly in the current Falcon interstage. Even with the nozzle trimmed back to 70% (which would put it very nearly in the Mvac envelope), it could realistically get 265 tonnes of thrust at 377s ISP. That's a healthy upgrade over Mvac's 95 tonnes thrust and 348 ISP.

I have no idea.  I was about to ask you, and everybody else.

What chamber pressures should we expect out of Raptor?  Do we have any evidence or reasoning one way or the other? (other than the previously mentioned 321s, 363s, 380s, and 3.8:1, and "FFSC should permit higher chamber pressures" notion)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 06/23/2016 04:09 pm

I'm interested in seeing the top area of the booster, and see if there are some obvious changes to it for supporting the upper attachments.

Its simple.  It could be part of the nose cones or a ring between the core and nose cone. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 06/23/2016 04:15 pm
Punch it up to the RD-180 chamber pressure - 26.7MPa
Using the listed estimates for 3.8:1 inefficiencies rather than theoretical maxima in RPA Lite:
With an expansion ratio of 59, you get 321s at sealevel and 363s in vacuum.
With an expansion ratio of 164, you get 380s in vacuum.

Sidenote: Do we have a higher chamber pressure liquid rocket engine in existence than the RD-180?
RD-191, 262.6kg/cm˛ vs 261.7kg/cm˛. RD-270 was 266.1.  I know of nothing bigger than this. But some military RCS engines (like the one in MIRVs) probably have higher Pc.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gongora on 06/23/2016 04:16 pm
This one is definitely the core - the same side-booster attachment point appears on the lower side of the booster on one of the photos above, as you can see here. I'll bet they have an attach/release mechanism that links these "buffed up" core-booster fixtures to the existing Falcon 9 hold-down design to eliminate the need for any changes in the side booster octaweb design.
Is it possible FH sides and core share the same web structure?  In fact, this could be a new web for all boosters if the weight penalty is acceptable.  Then you only have one web part number which has production flow advantages.

I have a sneaking suspicion one could join L2 to find out.
3 Separate Octowebs. Similar for shared production but different for each role it plays. F9, FH Core, FH Booster.

Are you guessing that or have you found information about it somewhere?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 06/23/2016 04:20 pm
This one is definitely the core - the same side-booster attachment point appears on the lower side of the booster on one of the photos above, as you can see here. I'll bet they have an attach/release mechanism that links these "buffed up" core-booster fixtures to the existing Falcon 9 hold-down design to eliminate the need for any changes in the side booster octaweb design.
Is it possible FH sides and core share the same web structure?  In fact, this could be a new web for all boosters if the weight penalty is acceptable.  Then you only have one web part number which has production flow advantages.

I have a sneaking suspicion one could join L2 to find out.
3 Separate Octowebs. Similar for shared production but different for each role it plays. F9, FH Core, FH Booster.

Are you guessing that or have you found information about it somewhere?

It appears to be a fact, not speculation. Again, read this Reddit thread extract, focusing on what the guy tagged as "ex-SpaceX" writes: https://www.reddit.com/r/spacex/comments/3ybhtt/what_will_fly_first_the_falcon_heavy_or_the_sls/cyciu7m
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 06/23/2016 04:52 pm
For the record, the ex-SpaceX guy in the Reddit thread says he built octawebs (so he knows whereof he speaks) and that SpaceX has three different octaweb part numbers for three different octaweb configurations.

He says this in the context of stating that an F9 core cannot simply be "reassigned" to an FH, because the structural attachment points are different. So they end up with three somewhat different core/booster structural assemblies (F9, FH core, FH booster) whose differences include different octawebs.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: matthewkantar on 06/23/2016 05:16 pm
Wild guess, is it possible that the three cores need to be mated before the engines go in? Maybe four engines on each core need to be absent to mate up the boosters, so they decided to install them all in Florida where the all up static fire will take place.

Though this seems unlikely to me, they are into a whole new test procedure with the Heavy.

Matthew
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 06/23/2016 05:18 pm
Wild guess, is it possible that the three cores need to be mated before the engines go in? Maybe four engines on each core need to be absent to mate up the boosters, so they decided to install them all in Florida where the all up static fire will take place.


No, they should be able to mate them with the engines installed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MrHollifield on 06/23/2016 05:46 pm
Yep. But you missed another new feature, which appears to be the main load bearing one for the octaweb. I have circled the three new Octaweb features (red), and overlaid a simple line drawing to indicate how I assume it will connect to the FH core (blue):

This one is definitely the core - the same side-booster attachment point appears on the lower side of the booster on one of the photos above, as you can see here.

I must respectfully disagree. The hold-down points on both stages outside SpaceX are very different from the hold-down points on the returned CRS booster, so I don't think either is the returned ORBCOMM S1. Also, both stages have an additional feature at 45 degrees between the hold downs. It appears to me these are identical stages--most likely the side boosters of the first FH (and it would make sense for them both to be processed for shipment at the same time).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 06/23/2016 05:51 pm
I must respectfully disagree. The hold-down points on both stages outside SpaceX are very different from the hold-down points on the returned CRS booster, so I don't think either is the returned ORBCOMM S1. Also, both stages have an additional feature at 45 degrees between the hold downs. It appears to me these are identical stages--most likely the side boosters of the first FH (and it would make sense for them both to be processed for shipment at the same time).

Check out the photos of the two stages here:

http://imgur.com/a/q7yoL

One if these is clearly a returned F9 stage, not a new FH core/booster. The photos show the scorching at the base of the rocket, missing TPS, etc.

No question it's the Orbcomm stage, IMO.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MrHollifield on 06/23/2016 06:00 pm
Yeah, got to that thread right after posting here :-[

That being said, the top picture of the 4 higher up in this thread is not the same stage parked in the same place as the other 3 photos in the group. It may be the same booster in a different place or a different booster in a different place, but it is definitely a new stage of the FH design and not the ORBCOMM stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MikeAtkinson on 06/23/2016 06:08 pm
Yeah, got to that thread right after posting here :-[

That being said, the top picture of the 4 higher up in this thread is not the same stage parked in the same place as the other 3 photos in the group. It may be the same booster in a different place or a different booster in a different place, but it is definitely a new stage of the FH design and not the ORBCOMM stage.

Yes, note the street lamp, trees, support equipment and position in the road.

I think it is most likely the same stage, just that it has been moved.

Suggest SpaceX are installing engines at McGregor to increase stage throughput in Hawthorne.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 06/23/2016 06:10 pm
Yeah, got to that thread right after posting here :-[

That being said, the top picture of the 4 higher up in this thread is not the same stage parked in the same place as the other 3 photos in the group. It may be the same booster in a different place or a different booster in a different place, but it is definitely a new stage of the FH design and not the ORBCOMM stage.

I think it actually is the same stage. It's an FH core or booster. First pic is taken inside the parking lot looking out. Second pic is from street looking in, in (slightly?) different position (same street light pole?)

Second and third pics taken at same location. FH core/booster in front, Orbcomm stage behind. Notice the building's same high bay door opening in the last two pics.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MikeAtkinson on 06/23/2016 06:11 pm
For the record, the ex-SpaceX guy in the Reddit thread says he built octawebs (so he knows whereof he speaks) and that SpaceX has three different octaweb part numbers for three different octaweb configurations.

He says this in the context of stating that an F9 core cannot simply be "reassigned" to an FH, because the structural attachment points are different. So they end up with three somewhat different core/booster structural assemblies (F9, FH core, FH booster) whose differences include different octawebs.

While that is still likely to be true, he seems to have been an ex=SpaceX employee for 6 months or so. Given the rate that SpaceX iterate on designs, they might have changed to fewer octoweb variants.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 06/23/2016 06:18 pm
For the record, the ex-SpaceX guy in the Reddit thread says he built octawebs (so he knows whereof he speaks) and that SpaceX has three different octaweb part numbers for three different octaweb configurations.

He says this in the context of stating that an F9 core cannot simply be "reassigned" to an FH, because the structural attachment points are different. So they end up with three somewhat different core/booster structural assemblies (F9, FH core, FH booster) whose differences include different octawebs.

While that is still likely to be true, he seems to have been an ex=SpaceX employee for 6 months or so. Given the rate that SpaceX iterate on designs, they might have changed to fewer octoweb variants.

Anything's possible, but it wouldn't make basic engineering sense. F9 doesn't need booster attach points. FH core needs booster attach points on both sides. FH boosters need core attach points on one side only. Extraneous (very beefy) attach points add performance-dragging mass that you would rather save for boostback propellant margin instead of dead useless metal.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/23/2016 06:22 pm
Anything's possible, but it wouldn't make sense. F9 doesn't need booster attach points. FH core needs booster attach points on both sides. FH boosters need core attach points on one side only.

But FH core need mass optimization, F9 and FH boosters not at the same level.
Having the same frame with some add-ons could be a good option.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 06/23/2016 06:42 pm
For the record, the ex-SpaceX guy in the Reddit thread says he built octawebs (so he knows whereof he speaks) and that SpaceX has three different octaweb part numbers for three different octaweb configurations.

He says this in the context of stating that an F9 core cannot simply be "reassigned" to an FH, because the structural attachment points are different. So they end up with three somewhat different core/booster structural assemblies (F9, FH core, FH booster) whose differences include different octawebs.

While that is still likely to be true, he seems to have been an ex=SpaceX employee for 6 months or so. Given the rate that SpaceX iterate on designs, they might have changed to fewer octoweb variants.

Anything's possible, but it wouldn't make basic engineering sense. F9 doesn't need booster attach points. FH core needs booster attach points on both sides. FH boosters need core attach points on one side only. Extraneous (very beefy) attach points add performance-dragging mass that you would rather save for boostback propellant margin instead of dead useless metal.

If the rest of the side core is like a regular F9, it would make sense to start making all F9 to be side cores...

So right now they have 3 part numbers:
- Regular
- Side core
- Center core

But as heavy start flying, in order to gain operational flexibility, you can stop making "regulars".
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/23/2016 06:55 pm
FH side boosters won't have an interstage, so they cannot fly as F9's.

There's no great advantage in having a specific booster be usable for multiple roles. The big advantage is using common tooling, production lines, test facilities, transport, storage, GSE, etc.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 06/23/2016 06:55 pm
Quote
But as heavy start flying, in order to gain operational flexibility, you can stop making "regulars".

They could, but but with most of those "regulars" going to GTO with razor-thin performance margins for recovery, I doubt SpaceX would choose to add the dead weight. Remember, it's not just the octaweb. It's also the upper attachment point(s), with whatever localized beefing up of the tank that requires. That may be a significant weight hit to a "regular" F9 that could be the difference between recovering and not recovering a GTO stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/23/2016 06:58 pm
Anything's possible, but it wouldn't make basic engineering sense. F9 doesn't need booster attach points. FH core needs booster attach points on both sides. FH boosters need core attach points on one side only. Extraneous (very beefy) attach points add performance-dragging mass that you would rather save for boostback propellant margin instead of dead useless metal.

Bold mine.
IMHO main load transfer points between FH core and FH boosters are the facing hold down points on the octaweb.
They are not added, but strong points already built in, freed from their original task and repurposed.
This means no performance-dragging mass is added.
That's why in my previous post I evidenced only the new compression point (likely only for some stabilization beam).
The strong load bearing points are not new, but repurposed (with slightly new shape) hold down attachments.
As always: my opinion.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rcoppola on 06/23/2016 08:13 pm
Question about attachment points and ignition sequence:

Will SpaceX continue with their preference for nondestructive pneumatic releases for their booster separation events? I'm assuming absolutely for the upper attachment armature since that seems to be designed for retraction/re-use.

Do we think they will stagger engine ignitions like the DIVH does? Or light all 3 simultaneously?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 06/23/2016 08:44 pm
Quote
Do we think they will stagger engine ignitions like the DIVH does? Or light all 3 simultaneously?

At least two problems with air-starting the center core: it increases the structural loads on the side boosters to have to carry the non-thrusting core off the pad, and then you need all (?) core engines to start nominally with no opportunity to abort the launch if they don't. 

Pad ignition of the core engines mitigates both those issues. They can gain some performance benefit by throttling down the core engines until after booster staging.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 06/23/2016 09:00 pm
Question about attachment points and ignition sequence:

Will SpaceX continue with their preference for nondestructive pneumatic releases for their booster separation events? I'm assuming absolutely for the upper attachment armature since that seems to be designed for retraction/re-use.

Yes. Correct. For the same reasons too.


Quote
Do we think they will stagger engine ignitions like the DIVH does? Or light all 3 simultaneously?

DIVH does that (recently) to reduce booster charring due to RS68 excess hydrogen buildup on startup:
United Launch Alliance Answers Burning Questions about Orion's Rocket (http://www.planetary.org/blogs/jason-davis/2014/20141126-ula-burning-questions.html)

It's an artifact from the engine's cost reduction development path as it departed from SSME.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 06/23/2016 09:08 pm
Quote
Do we think they will stagger engine ignitions like the DIVH does? Or light all 3 simultaneously?

At least two problems with air-starting the center core: it increases the structural loads on the side boosters to have to carry the non-thrusting core off the pad, and then you need all (?) core engines to start nominally with no opportunity to abort the launch if they don't. 

Staggered ignition is not the same as air-start. We know FH won't air-start the core. (unless you count the post-staging braking and landing burns)  ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 06/23/2016 09:19 pm
Quote
Do we think they will stagger engine ignitions like the DIVH does? Or light all 3 simultaneously?

At least two problems with air-starting the center core: it increases the structural loads on the side boosters to have to carry the non-thrusting core off the pad, and then you need all (?) core engines to start nominally with no opportunity to abort the launch if they don't. 

Staggered ignition is not the same as air-start. We know FH won't air-start the core. (unless you count the post-staging braking and landing burns)  ;)

Sorry, I thought the question was a resumption of this discussion:

http://forum.nasaspaceflight.com/index.php?topic=40503.msg1549418#msg1549418

Now I understand the question.  ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 06/23/2016 09:36 pm
At least two problems with air-starting the center core: it increases the structural loads on the side boosters to have to carry the non-thrusting core off the pad,

FH like DIVH lifts from the base. So the core accepts the load through stiffened load paths, the only difference between a ground start and an air start for loads would be in minor degree.

Quote
and then you need all (?) core engines to start nominally with no opportunity to abort the launch if they don't. 

Most significant - you have to start all the engines well ahead of launch. The 28th Merlin is the only one air started.

If you have to start all of them before launch to determine if launch, they are all running to begin with.

All that is left is throttle level and props consumption management. You want to depart the pad, roll/pitch to orient to azimuth/ascent, and throttle optimally for specific mission with full depletion for the boosters and minimal depletion for the core stage, bounded by the payload's limits of acceleration.

If you had cross feed and no acceleration limits, ideally the core's engines and the boosters would all be at maximum til earliest booster separation, preserving maximum core propellant - this would be better than air start because of less gravity losses (core engines are lifting own weight + more), and the core could burn for just as long.

Air start makes sense for solids/hypers. Better choice for FH vehicle/risk trade off likely is  cross feed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 06/24/2016 03:35 am
FH side boosters won't have an interstage, so they cannot fly as F9's.

There's no great advantage in having a specific booster be usable for multiple roles. The big advantage is using common tooling, production lines, test facilities, transport, storage, GSE, etc.

That statement makes no sense in the context of reusability.  It only makes sense for one-offs.

If each core is used many times, of course interchangeability helps.  Or else you need to launch a heavy, but don't currently have side cores ready, so have to wait, etc.

It's why commonality is so popular in transport systems.

It's why you have the same rocket carry Dragons and payloads that use fairings...  Because you don't want different types of trucks for different types of payloads - unless absolutely necessary (e.g. center core)

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 06/24/2016 03:41 am
Except look at SpaceX's hangar. It's not like SpaceX is going to shut down their factory and not make any more cores. They'll have plenty of cores available of any type. There will be no reason to use the non-optimal core type because SpaceX will not be starved of cores.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: meekGee on 06/24/2016 03:59 am
At least two problems with air-starting the center core: it increases the structural loads on the side boosters to have to carry the non-thrusting core off the pad,

FH like DIVH lifts from the base. So the core accepts the load through stiffened load paths, the only difference between a ground start and an air start for loads would be in minor degree.

Quote
and then you need all (?) core engines to start nominally with no opportunity to abort the launch if they don't. 

Most significant - you have to start all the engines well ahead of launch. The 28th Merlin is the only one air started.

If you have to start all of them before launch to determine if launch, they are all running to begin with.

All that is left is throttle level and props consumption management. You want to depart the pad, roll/pitch to orient to azimuth/ascent, and throttle optimally for specific mission with full depletion for the boosters and minimal depletion for the core stage, bounded by the payload's limits of acceleration.

If you had cross feed and no acceleration limits, ideally the core's engines and the boosters would all be at maximum til earliest booster separation, preserving maximum core propellant - this would be better than air start because of less gravity losses (core engines are lifting own weight + more), and the core could burn for just as long.

Air start makes sense for solids/hypers. Better choice for FH vehicle/risk trade off likely is  cross feed.

You're right about the center core, but Kabloona was talking about the side cores.  They will have to carry more, but the effect will only be on their thrust structure, not on their tanks.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 06/24/2016 01:42 pm
Quote
You're right about the center core, but Kabloona was talking about the side cores.  They will have to carry more, but the effect will only be on their thrust structure, not on their tanks.

In any case, I misunderstood the question, so we can ignore my irrelevant answer.  ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/24/2016 03:04 pm
FH side boosters won't have an interstage, so they cannot fly as F9's.

There's no great advantage in having a specific booster be usable for multiple roles. The big advantage is using common tooling, production lines, test facilities, transport, storage, GSE, etc.

That statement makes no sense in the context of reusability.  It only makes sense for one-offs.

If each core is used many times, of course interchangeability helps.  Or else you need to launch a heavy, but don't currently have side cores ready, so have to wait, etc.

It's why commonality is so popular in transport systems.

It's why you have the same rocket carry Dragons and payloads that use fairings...  Because you don't want different types of trucks for different types of payloads - unless absolutely necessary (e.g. center core)

Heavy is it's own vehicle. They will build a Heavy - core, side boosters, and all, and fly it. When the core is ready to fly again, the side boosters will have to be ready as well. The only time they could replace side boosters with a F9 core is by taking a side booster out of circulation. Heavy payloads cost hundreds of millions of dollars and have years of leadtime. They don't (yet) just "need to launch a heavy" is any way that won't allow a whole vehicle to be processed.

Right now boosters are one-offs, matched to payloads well ahead of time and run through a just in time manufacturing and test process. That's not going to change for a while. By the time it DOES change so that payload integration happens on whichever booster is ready, boosters will be retired (not crashed on droneships). New boosters will be run through the process at a rate to match retirement.

The advantage of some process flow optimization likely isn't, at this point, very high compared to optimization of boosters for specific tasks. Heavy is a lot more capable if it doesn't use regular F9s for side boosters.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Coastal Ron on 06/24/2016 03:13 pm
The only time they could replace side boosters with a F9 core is by taking a side booster out of circulation.

Maybe I'm interpreting this wrong, but from what we've been hearing a Falcon 9 core could not be used as a Falcon Heavy core since it lacks the strengthening upgrades and attachment points of a FH core.  You could probably fly a Falcon Heavy core without boosters though (as a single stick rocket), but I'm not sure why (or if) that situation would ever arise.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/24/2016 03:17 pm
The only time they could replace side boosters with a F9 core is by taking a side booster out of circulation.

Maybe I'm interpreting this wrong, but from what we've been hearing a Falcon 9 core could not be used as a Falcon Heavy core since it lacks the strengthening upgrades and attachment points of a FH core.  You could probably fly a Falcon Heavy core without boosters though (as a single stick rocket), but I'm not sure why (or if) that situation would ever arise.

Would require replacing the interstage with a nose cone, at least. And it's probably structural overkill... the F9 S1 sees aero and accel loads that the FH boosters never would.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 06/24/2016 04:05 pm

It's why you have the same rocket carry Dragons and payloads that use fairings...  Because you don't want different types of trucks for different types of payloads - unless absolutely necessary (e.g. center core)


Not a relevant analogy.  Capsules and fairings have always been interchangeable because capsules are designed to the rocket.   The basic vehicle design is with a fairing and then a capsule is designed around the vehicle's capabilities.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: 411rocket on 06/24/2016 05:43 pm
The only time they could replace side boosters with a F9 core is by taking a side booster out of circulation.

Maybe I'm interpreting this wrong, but from what we've been hearing a Falcon 9 core could not be used as a Falcon Heavy core since it lacks the strengthening upgrades and attachment points of a FH core.  You could probably fly a Falcon Heavy core without boosters though (as a single stick rocket), but I'm not sure why (or if) that situation would ever arise.

Would require replacing the interstage with a nose cone, at least. And it's probably structural overkill... the F9 S1 sees aero and accel loads that the FH boosters never would.

I could also see them, putting the nose cone on top of the interstage, so it can be easily removable & the crane lifting rig installed. As I do not think, the nose cone will be strong enough, for lifting & rotation to horizontal, after recovery.

Ms Shotwell, had also previously stated, to the effect of wanting to produce 2 varieties of the 1st stages. I am taking that, as the FH core & boosters that could also double as F9 stages.

That could take some time to happen, so I consider it a wait & see situation.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/24/2016 05:53 pm
All the FH renderings have boosters with nosecones replacing interstages, not sitting on them. Granted, artistic license and all that, but you'd think they would get the height the booster right of they are putting in details like conformal solar panels on dragon's trunk.

We should see if the nosecones are lifting points when they get handled at McGregor. Vertical rotation there is done by crane.

The interstage and 2nd stage hold/sep system is useless mass on a strap on booster.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/24/2016 06:09 pm
Grid fins should have been already fitted on first stage (instead of interstage).
If nose cone and interstage will be bolted on you could swap them easily.
Anyway part count reduction has ever been a “good thing to have“ for Elon.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: whitelancer64 on 06/24/2016 07:19 pm
Grid fins should have been already fitted on first stage (instead of interstage).
If nose cone and interstage will be bolted on you could swap them easily.
Anyway part count reduction has ever been a “good thing to have“ for Elon.

The grid fins and RCS systems are mounted on the bottom of the interstage, as you can see:

(http://www.extremetech.com/wp-content/uploads/2016/01/HBz5VPs.jpg)

(http://www.spaceflightinsider.com/wp-content/uploads/2016/04/5780-spacex_falcon_9_falcon_returns-michael_howard.jpg)

SpaceX will either A. put a nose cone on top of the interstage, B. cut down the interstage so there's just enough room for the RCS and grid fins and then put a nose cone on top of that, or C. develop a nose cone with the RCS and grid fins installed in it and then put that on top of the booster.

B makes the most sense to me.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/24/2016 07:24 pm
No more.
http://forum.nasaspaceflight.com/index.php?topic=39516.msg1509274#msg1509274
Also renderings on SpaceX site show grid fins on upper part of first stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: whitelancer64 on 06/24/2016 07:38 pm
No more.
http://forum.nasaspaceflight.com/index.php?topic=39516.msg1509274#msg1509274
Also renderings on SpaceX site show grid fins on upper part of first stage.

Mounting the RCS and grid fin plumbing inside the LOX tank sounds like a terrible idea to me.

They might make the interstage a separate assembly from the top of the first stage, but I think there's still going to be a short interstage section, integrated to the top of the first stage, where the RCS and grid fins are mounted.

Clicking on "Inside the Interstage" on the Falcon 9 page on spacex.com seems to show the grid fins mounted like that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/24/2016 07:54 pm
 I never said “inside the LOX tank“.
I said “first stage“...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: whitelancer64 on 06/24/2016 07:58 pm
I never said “inside the LOX tank“.
I said “first stage“...

So in a short interstage section mounted on the top of the stage. Thank you.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/24/2016 08:09 pm
I never said “inside the LOX tank“.
I said “first stage“...

So in a short interstage section mounted on the top of the stage. Thank you.
No.
Not mounted.
Integral part.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: whitelancer64 on 06/24/2016 08:13 pm
I never said “inside the LOX tank“.
I said “first stage“...

So in a short interstage section mounted on the top of the stage. Thank you.
No.
Not mounted.
Integral part.

Yes, as opposed to the RCS and grid fins being on the interstage, a short barrel will be on the top of the first stage. The interstage will be a little shorter now. I got it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 06/24/2016 09:18 pm
No more.
http://forum.nasaspaceflight.com/index.php?topic=39516.msg1509274#msg1509274
Also renderings on SpaceX site show grid fins on upper part of first stage.

Save yourself some arguing - Don't take those renderings as literal and exact engineering drawings. They are demonstrably WRONG on some details. The current "F9v1.2" grid fin placement does NOT match the image. The grid fins are in reality a part of the interstage. (Of course the "interstage" for SpaceX vehicles are part of the first stage, but by this I mean that the grid fins are NOT mounted on the outside the LOX tank)

The FH booster grid fins and RCS will either be in A) the nose cone or B) a truncated 'interstage' underneath the nose cone. We don't know yet.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/25/2016 12:37 pm
Image from SpaceX (march 2016).
Clearly visible on the aluminium barrel a manhole (circled in yellow), the holes for interstage interface/bolting (circled in green) and a new feature (circled in red, spotted by dorkmo, here (http://forum.nasaspaceflight.com/index.php?topic=39516.msg1509250#msg1509250))
That new feature seems the attachment point of grid fins.
We will see soon...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: RonM on 06/25/2016 03:17 pm
There are four grid fins. If the feature circled in red is a grid fin attachment, then we should see at least one more attachment in the photo, but there is only one.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mvpel on 06/25/2016 03:39 pm
Image from SpaceX (march 2016).
Clearly visible on the aluminium barrel a manhole (circled in yellow), the holes for interstage interface/bolting (circled in green) and a new feature (circled in red, spotted by dorkmo, here (http://forum.nasaspaceflight.com/index.php?topic=39516.msg1509250#msg1509250))
That new feature seems the attachment point of grid fins.
We will see soon...

The yellow item has been seen on various other stages in the past. My guess was that it was a burst disk for the oxygen tank, but I never got any further information about it. You can see it on this photo of the OG2 booster:

(https://danspace77.files.wordpress.com/2015/12/15-256b.jpg)
Title: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Johnnyhinbos on 06/25/2016 03:41 pm
(And the nosecone is in the background of the image two posts up)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: apirie98 on 06/25/2016 03:42 pm
Image from SpaceX (march 2016).
Clearly visible on the aluminium barrel a manhole or whatever it actually (circled in yellow), the holes for interstage interface/bolting (circled in green) and a new feature (circled in red, spotted by dorkmo

This appears to be the top section of the first stage (just below the interstage.) On the attached image of the landed JCSAT-14 core the manhole can be seen in the centre of the image.
The feature circled in red looks to me to have more to do with being the top of the raceway up the side of the stage which houses various umbilicals.
So it's nothing to do with the grid fins.

Image source https://www.flickr.com/photos/spacex/26822458066/in/photostream/
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/25/2016 04:36 pm
@RonM,
Still working on that barrel, holes for interstage/nosecone mounting still not completed.
This could be one of the grid fins attachments, others to be machined later.
@mvpel,
a burst disk? yes, it is possible.
@apirie98,
yes, could be the top of the raceway.
Compared to the manhole/burst disk, the angle is right.
But the height is not, very different, not the same.
We will see...

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/25/2016 06:27 pm
Food for thought.
@apirie98,
I think you got something I missed, angular position of the raceway corresponds perfectly with that red circled feature.
Nevertheless the true top of that raceway is on the interstage.
In the pic of OC2 stage you can see the raceway and the manhole/burst disk (very close to the interstage).
Position of the manhole/burst disk on the barrel is far from the stage-interstage joint.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: darkenfast on 06/26/2016 08:12 am
Is there another "manhole" located lower down on the fuel tank?  That could be what we are looking at on the vertical aluminum barrel section.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: apirie98 on 06/26/2016 02:25 pm
Is there another "manhole" located lower down on the fuel tank?  That could be what we are looking at on the vertical aluminum barrel section.

There is one at the bottom end of the stage on the bit that gets sooted/charred during re-entry.

Compared to the manhole/burst disk, the angle is right.
But the height is not, very different, not the same.
We will see...

Comparing photos I must admit to having changed my mind - the bottom hatch looks to be a better match with the factory photo (that entire section looks to be roughly the same size as the upper half of the sooted section.)

Still thinking that the red circled feature is the raceway though - there's a bulge in the raceway at that height on the picture below that is probably covering something.

What sells it to me the most though is the vertical lines (I'm sure they have a proper name) that have been visible in the soot patterns at the bases of all returned stages to date; the same pattern is visible on the section in the factory, and with respect to the hatch these seem to be in matching positions in both images. As far as I'm aware they aren't visible at the top of the stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/26/2016 03:44 pm
@apirie98,
good catch, and very interesting notes.
The vertical lines visible in the soot pattern are most probably traces of the internal construction of the RP-1 tank (featuring internal stringers).
Friction stir welding of these stringers could cause external lines on barrels also (something similar is visible on the barrel we are discussing).
Therefore, if that barrel is a RP-1 tank barrel, my observation about the possible relocation of grid fins would be wrong.
But (ouch, what a nagging guy I am!) the holes drilled in the lower part of that barrel aren't visible elsewere in the stage other than in the interface between first stage and interstage. Did you see somewhere else a similar feature? Can you think at other reasons why those holes have been drilled?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 06/26/2016 04:20 pm
Looking better, the holes drilled in that barrel could be only for reference.
A pin in the fixture between the two wheels would fix perfectly the barrel to certain positions.
That part of the barrel could be removed later.
Well, most probably this is a RP-1 tank barrel and the relocation of grid fins is only a fuss I created. :-[

Anyway, thanks apirie98 for the discussion  ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: apirie98 on 06/26/2016 06:46 pm
But (ouch, what a nagging guy I am!) the holes drilled in the lower part of that barrel aren't visible elsewere in the stage other than in the interface between first stage and interstage. Did you see somewhere else a similar feature? Can you think at other reasons why those holes have been drilled?

I can only speculate that it may be related to the way they join two of the sections of the stage together - see the comparison below.
Above the stringers there is a sort of band. On the core section in the factory there's those holes on the band and then on the landed core there's a line at the same level where the holes are. It looks to my untrained eye like the two are related in some way, but I wouldn't want to hazard a guess how (I have more or less no knowledge of the techniques they use to produce these stages.)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Saabstory88 on 06/28/2016 01:12 pm
(https://scontent-lhr3-1.cdninstagram.com/t51.2885-15/e35/13129503_991141820994105_775004864_n.jpg?ig_cache_key=MTI0OTQxMDI0MzA1ODQwMzM3MA%3D%3D.2)

The grid fins will be mounted on the straight section of the nosecone. The hole is clearly visible.

Edit: And what do you know, it just happens to match the wind tunnel model.

(http://i.imgur.com/ZJfbZzz.jpg)

Further edit: This isn't KSP or Rocket Lego's, if you need a straight section above the tank to mount something, you just make the cone the proper shape. No need to "put a cone on top of a chopped off interstage".
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dgkimpton on 06/28/2016 02:01 pm
That wind tunnel model is awesome :D thanks! Also, the nose cone in traffic puts a real sense of scale on this thing... it's... er... huge!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/28/2016 02:22 pm
That wind tunnel model is awesome :D thanks! Also, the nose cone in traffic puts a real sense of scale on this thing... it's... er... huge!

This fact isn't stated enough. Falcon Heavy is an extremely big launcher.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 06/28/2016 02:50 pm
That wind tunnel model is awesome :D thanks! Also, the nose cone in traffic puts a real sense of scale on this thing... it's... er... huge!

The picture of the wind tunnel model makes me feel all warm and happy inside.

Edit: The FH is huge, super huge. Which it needs to be in order to have all 3 booster cores do RTLS and still deliver 7 tons to GTO.

What it can throw in fully expendable mode, oh boy!!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: First Mate Rummey on 06/28/2016 03:24 pm
Is the FH Fairing bigger than the one currently used in F9?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 06/28/2016 03:25 pm
Is the FH Fairing bigger than the one currently used in F9?
I don't believe so yet, but I think they might be developing a larger one.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: First Mate Rummey on 06/28/2016 03:29 pm
This one seems hugely bigger than the one on F9!

(http://i.imgur.com/ZJfbZzz.jpg)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 06/28/2016 03:40 pm
This one seems hugely bigger than the one on F9!


It isn't, it is the same size
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 06/28/2016 03:41 pm
That's just camera perspective and distortion. It's the standard 5.2m fairing.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dgkimpton on 06/29/2016 05:38 pm
which is huge... my whole house is only 4m wide... gotta be close to being able to fit the entire first story inside the fairing  :o
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 06/29/2016 05:43 pm
which is huge... my whole house is only 4m wide... gotta be close to being able to fit the entire first story inside the fairing

Ariane, Atlas V and Delta IV have the same diameter and longer hence larger fairings.  And Titan IV had even longer fairings more than 20 years ago.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: docmordrid on 06/29/2016 06:04 pm
True about the width, but in the case of Centaur upper stages 7+ meters of a fairings gross length encapsulates said  upper stage and isn't available for cargo.  Need to discuss net length vs net length.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 06/29/2016 06:20 pm
True about the width, but in the case of Centaur upper stages 7+ meters of a fairings gross length encapsulates said  upper stage and isn't available for cargo.  Need to discuss net length vs net length.

The Atlas V, Titan IV and Delta IV have cylindrical sections that are 40 feet long which doesn't include nose cone or boat tails or upper stages.  The F9 cylindrical section is under 22 feet.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: baldusi on 06/29/2016 09:55 pm
6.6m for Falcon, over 12m for Atlas V, Titan IV and Delta IV.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Nomadd on 06/29/2016 10:20 pm
Filler
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Chris_Pi on 07/01/2016 03:45 am
I responded to the quote below earlier, But it's looking like that's the paintjob it'll ship with so probably no masking still on. Anyone seen the second one? I'm curious if they'll change the pattern some to distinguish the two cores from each other.

It may be just extra paint over masking, but it looks like it was painted by a 3rd grader. Also looks like it was brushed on, any ideas about that?

Matthew
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 07/01/2016 04:57 am
I responded to the quote below earlier, But it's looking like that's the paintjob it'll ship with so probably no masking still on. Anyone seen the second one? I'm curious if they'll change the pattern some to distinguish the two cores from each other.

It may be just extra paint over masking, but it looks like it was painted by a 3rd grader. Also looks like it was brushed on, any ideas about that?

Matthew

What gives you the idea that A) that is flight hardware and B) if so it is the paint job it will ship with? They are months away from flight.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 07/01/2016 10:39 am
I responded to the quote below earlier, But it's looking like that's the paintjob it'll ship with so probably no masking still on. Anyone seen the second one? I'm curious if they'll change the pattern some to distinguish the two cores from each other.

It may be just extra paint over masking, but it looks like it was painted by a 3rd grader. Also looks like it was brushed on, any ideas about that?

Matthew

What gives you the idea that A) that is flight hardware and B) if so it is the paint job it will ship with? They are months away from flight.

With all the white marks and not a finished paint job it looks more like a test article than flight hardware.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 07/19/2016 05:42 am
A quick question. From the Falcon 9 guide we know that the maximum payload that the rocket can carry is a littme more than 10 metric tons with the heavy payload adaptor.

At the same time, there has been some speculation that the way payloads are horizontally integrated (with the fairing playing a role in carrying the weight) makes attaching heavier payloads than the current max impossible, at least without major changes.

Do we have any information about whether the same technique for integration will be used in the Falcon Heavy too? This would put a hard payload limit for both vehicles a lot smaller than the theoretical performace.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 07/19/2016 06:28 am
A quick question. From the Falcon 9 guide we know that the maximum payload that the rocket can carry is a littme more than 10 metric tons with the heavy payload adaptor.

Is that a limitation of the payload adapter or the lifting power of the engines?

At the same time, there has been some speculation that the way payloads are horizontally integrated (with the fairing playing a role in carrying the weight) makes attaching heavier payloads than the current max impossible, at least without major changes.

So you want speculation based on speculation?  ;) What are you fishing for here?

Do we have any information about whether the same technique for integration will be used in the Falcon Heavy too? This would put a hard payload limit for both vehicles a lot smaller than the theoretical performace.

Oh I see, is this another "FH won't work because I have thought of something SpaceX must have missed" post?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 07/19/2016 07:46 am
Lars-J, that is a little harsh man. I am certainly not "fishing" for anything.  :-[

Quote
Is that a limitation of the payload adapter or the lifting power of the engines?

If I understand correctly, it has to do with the PAF. SpaceX uses one of two PAFs on the launch vehicle, based on payload mass. The light PAF can accommodate payloads weighing up to 3,453 kg (7,612 lb), while the heavy PAF can accommodate up to 10,886 kg (24,000 lb).

I assume that for bigger payloads, a custom PAF could be made, but I also read somewhere here that another limitation for max load is the horizontal integration procedure itself (the amount of force that the fairing can carry over when horizontal and when moving to vertical. I'm asking whether we know anything else about this limitation.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 07/19/2016 04:45 pm
I assume that for bigger payloads, a custom PAF could be made, but I also read somewhere here that another limitation for max load is the horizontal integration procedure itself (the amount of force that the fairing can carry over when horizontal and when moving to vertical. I'm asking whether we know anything else about this limitation.

*If* a stronger PAF is needed, I don't see the problem in making one. As far as horizontal integration mass issues, the PAF carries that load, not the fairing. The fairing supports itself, and has been horizontally integrated many times now.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 07/19/2016 06:25 pm
I think it's a legit question, if the payload itself is heavier, while it is horizontal there is more bending moment at the attachment point. Presumably usually that's handled because the TEL has clamps and supports and etc while horizontal. And presumably SpaceX of course already thought of this.

I see the question as wanting to know what's likely to have changed. The stage tank wall thickness hasn't changed presumably.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 07/19/2016 06:51 pm
I think it's a legit question, if the payload itself is heavier, while it is horizontal there is more bending moment at the attachment point. Presumably usually that's handled because the TEL has clamps and supports and etc while horizontal. And presumably SpaceX of course already thought of this.

I see the question as wanting to know what's likely to have changed. The stage tank wall thickness hasn't changed presumably.

Of course a heavier payload has more bending moment. The payload adapter (and the payload itself) has to support that. But - the fairing does not support the payload. Only its own (not insignificant) mass. See the image I drew up below - There is no contact between the payload and the fairing!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: bstrong on 07/19/2016 08:07 pm
Of course a heavier payload has more bending moment. The payload adapter (and the payload itself) has to support that. But - the fairing does not support the payload. Only its own (not insignificant) mass. See the image I drew up below - There is no contact between the payload and the fairing!

Others have claimed otherwise in the past. Ex:

Look at the pics in the users' guide, there are cradles around the fairing (with the payload inside) while it is getting mated to the second stage.  This means the weight of the payload is going from the adapter into the fairing.  Unlike Sealaunch, where the adapter supports the fairing and the payload horizontally

I've been quite curious why they do it this way and have never seen a good explanation for it or an answer to Dante80's question about the max load the fairing can support.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 07/19/2016 09:16 pm
I think it's a legit question, if the payload itself is heavier, while it is horizontal there is more bending moment at the attachment point. Presumably usually that's handled because the TEL has clamps and supports and etc while horizontal. And presumably SpaceX of course already thought of this.

I see the question as wanting to know what's likely to have changed. The stage tank wall thickness hasn't changed presumably.

Of course a heavier payload has more bending moment. The payload adapter (and the payload itself) has to support that. But - the fairing does not support the payload. Only its own (not insignificant) mass. See the image I drew up below - There is no contact between the payload and the fairing!
I'm talking about the bending moment on the payload adapter (and thus on the rest of the stack) from the payload.

There's going to also possibly be some increased bending moment on (?? fairing attach point) due to the fairing itself being heavier (IF it's made longer, no current plans to do so that we understand...)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 07/19/2016 09:29 pm
Of course a heavier payload has more bending moment. The payload adapter (and the payload itself) has to support that. But - the fairing does not support the payload. Only its own (not insignificant) mass. See the image I drew up below - There is no contact between the payload and the fairing!

Others have claimed otherwise in the past. Ex:

Look at the pics in the users' guide, there are cradles around the fairing (with the payload inside) while it is getting mated to the second stage.  This means the weight of the payload is going from the adapter into the fairing.  Unlike Sealaunch, where the adapter supports the fairing and the payload horizontally

I've been quite curious why they do it this way and have never seen a good explanation for it or an answer to Dante80's question about the max load the fairing can support.

The SpaceX fairing is by itself rather massive, yes, so it has in the past (at least first few launches) sometimes been supported while horizontal. (Can anyone dig up any recent evidence of this? I haven't seen any)

BUT... that support must be for the fairing's own mass, not the payload, as there - again - is no internal connection between the fairing and payload. All payload loads transfer through the payload adapter.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 07/19/2016 09:39 pm
No, Read my words agsin
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 07/19/2016 09:50 pm
No, Read my words agsin

I read what someone quoted from you. And I looked at the most recent F9 payload users guide:
http://www.spacex.com/sites/spacex/files/falcon_9_users_guide_rev_2.0.pdf

I see no such thing there. I assume you are referring to this image? (attached) If not, some specifics would be great. Where does the payload and fairing touch, other than through the payload adapter?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 07/19/2016 09:53 pm
Cradles are receiving part of the cantilevered load on the payload through the adapter, with the rest via the US skin.

When its been taken horizontal for mate.

Quote from: F9 payload users guide
Once at the launch vehicle integration hangar, the encapsulated assembly is rotated to horizontal and mated with the launch vehicle already positioned on its transporter-erector.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 07/19/2016 10:02 pm
There are figures that show the fairing and payload horizontal.  The fairing is supported by two stands during the mate to the upper stage.  The fixtures are not on the fairing during this.  So the whole payload mass goes in to the fairing
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MrHollifield on 07/19/2016 10:25 pm
Note 3 at the bottom of page 36 in the F9 Users Guide indicates the dimensions shown are those which, if the payload stays within them, prevent contact between the fairing and the payload. Therefore, I'm with Kabloona that both the fairing and the payload attach to the PAF, and the PAF to the 2nd stage, but there is no connection between the fairing and the payload.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 07/19/2016 10:29 pm
BUT... that support must be for the fairing's own mass, not the payload, as there - again - is no internal connection between the fairing and payload. All payload loads transfer through the payload adapter.

I think maybe you and Jim are saying the same thing in a different way. The fairing attaches to the base of the payload adapter. So after encapsulation, when the whole assembly is rotated horizontal and put on the cradle, the cradle is carrying both the weight of the fairing *and* the payload, but the only load path between the two is through the payload adapter.

So there is no contact between the fairing and payload per se, but when the encapsulated assembly is sitting horiztonal on a cradle before integration with the vehicle, the cradle is carrying the weight of both the fairing and the payload.

Then after integration, the TEL cradle arms touching the fairing (in SG's photo posted above) are reducing the bending load where the adapter attaches to S2.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: joek on 07/19/2016 10:35 pm
Like this; red line is load path (excuse the crude art)...

edit p.s. We have seen pictures of an encapsulated payload before (vertical) and after (horizontal) mating with the LV.  I have not seen a picture during mating going from vertical to horizontal, or with just the encapsulated payload horizontal, which is when the fairing would support the entire load (as shown).  If a support fixture is attached to the PAF, it would reduce or eliminate load on the fairing; no idea if that is possible or what SpaceX uses.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 07/19/2016 10:38 pm
Like this; red line is load path (excuse the crude art)...

1 picture = 1k words  ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: whitelancer64 on 07/19/2016 10:52 pm
The payload's connected to the payload adapter. The payload adapter's connected to the fairing. It seems everyone agrees on this.

That means - at least for a short time, after being rotated horizontal, prior to being mated to the rocket - the fairing is taking the weight of the payload, which is transmitted through the payload adapter to the fairing.

Makes vertical integration so much more appealing when these headaches are considered...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 07/19/2016 11:00 pm
Quote
Makes vertical integration so much more appealing when these headaches are considered...

Which is why SpaceX is avoiding VI like the plague?  ???

It's kind of like Churchill's quote about democracy: (HI is) the worst form of government (integration) except for all the others that have been tried...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 07/19/2016 11:15 pm
Cradles are receiving part of the cantilevered load on the payload through the adapter, with the rest via the US skin.

When its been taken horizontal for mate.

Quote from: F9 payload users guide
Once at the launch vehicle integration hangar, the encapsulated assembly is rotated to horizontal and mated with the launch vehicle already positioned on its transporter-erector.

I've seen that picture before, and that support is only temporary, for the transport out to the pad. Those fairing supports are removed once the rocket has been attached to the pad. Before and after it is attached/removed, it rests completely without it before it is raised vertical.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: whitelancer64 on 07/19/2016 11:20 pm
Quote
Makes vertical integration so much more appealing when these headaches are considered...

Which is why SpaceX is avoiding VI like the plague?  ???

It's kind of like Churchill's quote about democracy: (HI is) the worst form of government (integration) except for all the others that have been tried...

I don't think they're avoiding it, per se, but the infrastructure required to support it hasn't been built yet.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: joek on 07/19/2016 11:29 pm
I've seen that picture before, and that support is only temporary, for the transport out to the pad. Those fairing supports are removed once the rocket has been attached to the pad. Before and after it is attached/removed, it rests completely without it before it is raised vertical.

Yes; once it is mated the load should not be going through the fairing.  The question is what happens before during the mating process.  While we have seen before and after, I don't recall seeing a picture of an encapsulated payload during transition from vertical to horizontal during the mating process.  edit: Just to be clear, my lack of recall should not be taken as evidence of anything.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: joek on 07/19/2016 11:32 pm
And with respect to FH... IIRC the original discussion was prompted by the reported (high) mass of the payload fairing.  One reason, per Jim, is the need for the fairing to support the payload during integration to the LV.  If that is the case, the current fairing may be a limiting factor for heaver payloads.  If they have to build a different, beefier and heavier, fairing for heftier FH payloads, it may be another reason SpaceX is interested in fairing recovery.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 07/19/2016 11:33 pm
Cradles are receiving part of the cantilevered load on the payload through the adapter, with the rest via the US skin.

When its been taken horizontal for mate.

Quote from: F9 payload users guide
Once at the launch vehicle integration hangar, the encapsulated assembly is rotated to horizontal and mated with the launch vehicle already positioned on its transporter-erector.

I've seen that picture before, and that support is only temporary, for the transport out to the pad. Those fairing supports are removed once the rocket has been attached to the pad. For a short while, it rests completely without it before it is raised vertical.

You intentionally miss the point. You wanted something from your information source, the pdf. That's the closest you get that shows the support in that document. Everyone's been attempting to fill in the gap between what you and Jim were saying.

All means the same thing. I could go into how SeaLaunch handled it too, and a subtle difference Jim was alluding to. Suffice to say it allows for a lighter fairing absent the load path need. One could do the same with Falcon, but they don't because it would slow down integration for them.

I don't think you're that dense, you did get it. Why are we having this discussion other than ego salving? Why bother to answer any issue when its rendered pointless? Doesn't sound "excellent to each other" to me.

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 07/19/2016 11:57 pm
Like this; red line is load path (excuse the crude art)...

edit p.s. We have seen pictures of an encapsulated payload before (vertical) and after (horizontal) mating with the LV.  I have not seen a picture during mating going from vertical to horizontal, or with just the encapsulated payload horizontal, which is when the fairing would support the entire load (as shown).  If a support fixture is attached to the PAF, it would reduce or eliminate load on the fairing; no idea if that is possible or what SpaceX uses.

Bingo
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 07/20/2016 03:48 am
Cradles are receiving part of the cantilevered load on the payload through the adapter, with the rest via the US skin.

When its been taken horizontal for mate.

Quote from: F9 payload users guide
Once at the launch vehicle integration hangar, the encapsulated assembly is rotated to horizontal and mated with the launch vehicle already positioned on its transporter-erector.

I've seen that picture before, and that support is only temporary, for the transport out to the pad. Those fairing supports are removed once the rocket has been attached to the pad. For a short while, it rests completely without it before it is raised vertical.

You intentionally miss the point. You wanted something from your information source, the pdf. That's the closest you get that shows the support in that document. Everyone's been attempting to fill in the gap between what you and Jim were saying.

All means the same thing. I could go into how SeaLaunch handled it too, and a subtle difference Jim was alluding to. Suffice to say it allows for a lighter fairing absent the load path need. One could do the same with Falcon, but they don't because it would slow down integration for them.

I don't think you're that dense, you did get it. Why are we having this discussion other than ego salving? Why bother to answer any issue when its rendered pointless? Doesn't sound "excellent to each other" to me.

You have a point, perhaps I'm being too insistent here, but I really do think we are arguing very similar but not exactly the same thing. I may be in violent agreement with some here, but but the crux of my issue is this...

We don't know how the combined fairing/payload/adapter combination is handled as it is attached horizontally to the stack. If it is A) just sitting on its side before it is attached, then yes - all loads are being passed through the fairing. BUT... If B) it being lifted and rotated by its adapter base, then most of the load is *not* going through the fairing. Does that make sense? And *that* is the question that the PDF does not answer that at all. Any pictures of the fairing/payload/adapter combination being attached to the upper stage would be useful to see.

And that's all I'll post on this for a while.  :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MP99 on 07/20/2016 06:48 am


BUT... If B) it being lifted and rotated by its adapter base, then most of the load is *not* going through the fairing.

Even if that was true during lift & rotate, it doesn't look like that support could remain in place during mating of the payload to the upper-stage?

Cheers, Martin
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 07/20/2016 02:30 pm

We don't know how the combined fairing/payload/adapter combination is handled as it is attached horizontally to the stack. If it is A) just sitting on its side before it is attached, then yes - all loads are being passed through the fairing. BUT...

Yes, we do.  It is A, there is no device as depicted in B.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 07/20/2016 08:52 pm

We don't know how the combined fairing/payload/adapter combination is handled as it is attached horizontally to the stack. If it is A) just sitting on its side before it is attached, then yes - all loads are being passed through the fairing. BUT...

Yes, we do.  It is A, there is no device as depicted in B.

The problem with the "B" handling fixture shown above is that it would mate with the payload adapter right where you want the adapter to mate to the upper stage. Sort of like trying to hold a light bulb only by the threads, without touching the glass, while you attempt to screw it into the lamp socket.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: joek on 07/20/2016 09:16 pm
But purportedly Sea Launch achieved horizontal integration with some sort of widget or process that did not require the fairing to support the payload?  If not, then never mind.  If yes, then: (a) how did they do it; and (b) is whatever they did potentially applicable to SpaceX?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 07/20/2016 09:33 pm
This appears to be the SeaLaunch handling fixture for the encapsulated payload. Looks like it attaches to the base of the adapter, but there are also cradles under the fairing, though they seem to be retracted here.

I guess they figured out a way to screw in the light bulb while holding it only by the base...

(http://www.kosmonavtika.com/lancements/2014/26052014/26052014-4.jpg)

(http://www.kosmonavtika.com/lancements/2014/26052014/26052014-6.jpg)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 07/20/2016 09:55 pm
Yup. Thank you, you saved me the time to find it.

Please note the pivot trunnion bearing. Also, look at how SX integrates its vehicles and you'll see why something like this would complicate/slow down matters. Also, think of what happens with larger fairings when you use such.

Add:

Also note the cradle support below the fairing.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 07/20/2016 10:01 pm
Quote
Also note the cradle support below the fairing.

Presumably they encapsulate vertically, then break over horizontal, with everything supported at the base, and in the photos, the cradles under the fairings are retracted. So if the fairings aren't designed/intended to take side handling loads (as suggested earlier), why are the cradles there?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 07/20/2016 10:05 pm
So if the fairings aren't designed/intended to take side handling loads, why are the cradles there?
Used in transport, the same as with the Falcon picture in my post further above.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 07/20/2016 10:08 pm
So if the fairings aren't designed/intended to take side handling loads, why are the cradles there?
Used in transport, the same as with the Falcon picture in my post further above.

I thought someone upthread (Jim?) said the SeaLaunch fairing didn't take any handling load, ie different from Falcon 9. Are you saying that's incorrect? Not challenging you, just trying to understand. I don't know anything about their process.

There must be some difference though, because in the photo the cradles are retracted, taking no load, so at least in that photo, the stack appears to be entirely supported at the base, whereas with F9, the cradles have to be in contact with the fairing until after the encapsulated payload is attached to the upper stage.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 07/20/2016 10:19 pm
So if the fairings aren't designed/intended to take side handling loads, why are the cradles there?
Used in transport, the same as with the Falcon picture in my post further above.

I thought someone upthread said the SeaLaunch fairing didn't take any handling load, ie different from Falcon 9.
Are you saying that's incorrect?
No. The SeaLaunch load path is through the payload to the adapter and to the breakover/vertication fixture. We're talking about a different issue.

Post encapsulation (and in the Falcon case, integration with the vehicle) and in shipment, you can have dynamic thrusts that amplify the cantilever load of the fairing itself. So lets say in the above photo of the rollout of F9 at SLC-4E they hit a pothole, the integrated vehicle bends, and perhaps forms a fracture (or worse). Same issue as with the transport of the unmated, encapsulated SeaLaunch payload.

add:

It's a restraint on the bending allowance of the load of the fairing itself. That help?

edit: clarity.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 07/20/2016 10:24 pm
Cradles are to support the fairing before and during encapsulation.  Once the fairing is mated, the they can be pulled away.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 07/20/2016 10:47 pm
Cradles are to support the fairing before and during encapsulation.  Once the fairing is mated, the they can be pulled away.

OK, that makes sense. So they encapsulate horizontally, after which the fairing takes no side load through the cradles.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 07/20/2016 11:02 pm
This appears to be the SeaLaunch handling fixture for the encapsulated payload. Looks like it attaches to the base of the adapter, but there are also cradles under the fairing, though they seem to be retracted here.

I guess they figured out a way to screw in the light bulb while holding it only by the base...

(http://www.kosmonavtika.com/lancements/2014/26052014/26052014-4.jpg)


Yes, this is exactly what I had in mind - except hanging from a crane. But if Jim says that is not how SpaceX does it, I'll accept that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 07/21/2016 01:42 am
Isn't there another thread where we're discussing much the same thing?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: joek on 07/21/2016 02:30 am
Please note the pivot trunnion bearing. Also, look at how SX integrates its vehicles and you'll see why something like this would complicate/slow down matters. Also, think of what happens with larger fairings when you use such.

Sorry if I'm slow... I see a lot of fasteners with the PAF and fixture... is that what you are referring to that would complicate/slow down matters, or is it something else more intrinsic?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 07/21/2016 08:49 pm
SeaLaunch's "distance" from SC encapsulation (done by Astrotech, the same as SX launched DSCOVR, BTW) to vehicle integration to launch mid Pacific involved 1,000's of miles, a cruise, and typically 1-2 months (or more).

SX could/does more than this, assuming LV flow and US rate to match.

Overall what I meant was about complexity from a hundred sources don't want to detail. If you're only going to max out at 1-10 annual, makes sense to trade complexity/labor for payload . If you do 10+, you need to do something different. SeaLaunch never got that far. SX might, but they do so in a lean, minimalist way. Less to go wrong. If you want launch frequency ...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 07/21/2016 09:54 pm
SeaLaunch's "distance" from SC encapsulation (done by Astrotech, the same as SX launched DSCOVR, BTW) to vehicle integration to launch mid Pacific involved 1,000's of miles, a cruise, and typically 1-2 months (or more).


Astrotech doesn't do the encapsulation.  They only host a site for the operation.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 07/21/2016 10:07 pm
SeaLaunch's "distance" from SC encapsulation (done by Astrotech, the same as SX launched DSCOVR, BTW) to vehicle integration to launch mid Pacific involved 1,000's of miles, a cruise, and typically 1-2 months (or more).


Astrotech doesn't do the encapsulation.  They only host a site for the operation.

Where you hire/bring in those to work in doing so. Bit of the middleman too.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 07/21/2016 10:11 pm

Where you hire/bring in those to work in doing so. Bit of the middleman too.

Either the spacecraft can hire Astrotech or it is part of the launch service cost.  But either way, the spacecraft contractor processes the spacecraft and the LV contractor handles the fairing and encapsulation.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Space Ghost 1962 on 07/21/2016 10:51 pm

Where you hire/bring in those to work in doing so. Bit of the middleman too.

Either the spacecraft can hire Astrotech or it is part of the launch service cost.  But either way, the spacecraft contractor processes the spacecraft and the LV contractor handles the fairing and encapsulation.

Clear delineation of role and where responsibility rolls up to. One head for the mission, one for who gets it there.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: maitri982 on 08/01/2016 12:07 am
Launch of falcon heavy now pushed to 2017  :-[
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 08/01/2016 12:37 am
Launch of falcon heavy now pushed to 2017  :-[
Can you point to the source, please?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: maitri982 on 08/01/2016 01:56 am
Echo logic on spacex Reddit...seems to usually know what's going on before we do.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 08/01/2016 02:22 am
Echo logic on spacex Reddit...seems to usually know what's going on before we do.
Okay, so in other words, it's a rumor. Do you have a link to his comments? I cannot find your claim in his posts.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Gliderflyer on 08/01/2016 02:56 am
Echo logic on spacex Reddit...seems to usually know what's going on before we do.
Okay, so in other words, it's a rumor. Do you have a link to his comments? I cannot find your claim in his posts.
I don't know how true it is, but I believe I have found the comment: https://www.reddit.com/r/spacex/comments/4uhb7v/the_future_of_spacex/d5pq04b
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: maitri982 on 08/01/2016 03:15 am
That's the one...glad you found it!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: su27k on 08/01/2016 03:29 am
Not unexpected, given the last rumor has it launch during Christmas... I just hope it's not delaying one month by every month.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 08/01/2016 03:39 am
Echo logic on spacex Reddit...seems to usually know what's going on before we do.

He doesn't. Here is something from L2.

http://forum.nasaspaceflight.com/index.php?topic=34978.msg1563302#msg1563302 (http://forum.nasaspaceflight.com/index.php?topic=34978.msg1563302#msg1563302)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: maitri982 on 08/01/2016 03:44 am
I did not mean before nasaspaceflight in-the-know people...i meant before the laymen like myself.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: georgegassaway on 08/01/2016 04:10 am
Not unexpected, given the last rumor has it launch during Christmas... I just hope it's not delaying one month by every month.

Unfortunately, that's been the case for about 2 years if not longer, "six months from now".  For example,  IIRC, in  April 2015, it was scheduled to launch 6 months later, in  October 2015.   That was with no pad infrastructure work (April 2015), and only recently have they even attempted to begin the paperwork on two more landing Zones.

So given how long it took for LZ-1 to be built after its paperwork got started,  it would seem unlikely that a FH launch would have a 2nd LZ to use, never mind a 3rd one, by the planned launch date. Unless they sacrificed one booster to land in the ocean, RTLS the other booster, and land the core on OCISLY.  Or ran the process of at least building LZ-2 a LOT faster than they did for LZ-1, focusing on LZ-2 becoming ready, then complete LZ-3 later.

Anyway, when the schedule gets get down to *TWO* months, then maybe it'll launch 6 months after that 2 month scheduled NET date.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: high road on 08/01/2016 06:48 am
Two years ago, FH was still 'end of next year'. IIRC, it had been 'end of next year' for three years.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 08/01/2016 08:42 am
They should launch it when it'[s ready and they have a payload and there is nothing more important to do. I don't really care when that is. Plenty of other interesting stuff they are doing.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sdsds on 08/01/2016 09:28 am
There are competitors to FH, both external to SpaceX and internal as well (i.e. a rocket powered by Raptor). FH can't slip forever without risking being overtaken by events....
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 08/01/2016 11:04 am
There are competitors to FH, both external to SpaceX and internal as well (i.e. a rocket powered by Raptor). FH can't slip forever without risking being overtaken by events....

And if that the best way for them to proceed, then that's fine. They shouldn't have an F9H unless they need one, and event may mean they don't actually need one.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 08/01/2016 11:18 am
There are competitors to FH, both external to SpaceX and internal as well (i.e. a rocket powered by Raptor). FH can't slip forever without risking being overtaken by events....

And if that the best way for them to proceed, then that's fine. They shouldn't have an F9H unless they need one, and event may mean they don't actually need one.

They made FH necessary by announcing Red Dragon.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 08/01/2016 12:16 pm
There are competitors to FH, both external to SpaceX and internal as well (i.e. a rocket powered by Raptor). FH can't slip forever without risking being overtaken by events....

And if that the best way for them to proceed, then that's fine. They shouldn't have an F9H unless they need one, and event may mean they don't actually need one.

They made FH necessary by announcing Red Dragon.
...they may slip the 2018 window.

By the most optimistic timeline, 2020 could see the first flight of BFR.


But no matter. Falcon Heavy hardware exists today and will soon be tested in Texas.

In any case, a slip into 2017, still very much a rumor, is not (or should not) be a surprise to anyone.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rockets4life97 on 08/01/2016 01:18 pm
I would think if there is going to be a late December launch it will be the second Iridium NEXT launch. As one of their primary customers, I think that would take precedence over the first FH launch.

Right now, I would be truly surprised if SpaceX pulled off two late December launches (even from different pads). They haven't showed so far that they can accomplish this.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: spacenut on 08/01/2016 01:48 pm
Is pad 39a ready for Falcon Heavy to launch?  Are there two landing pads ready at Landing Zone 1?  They both have to be ready for a FH launch. 

Pad 40 can launch a F9 every two weeks if necessary. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 08/01/2016 02:27 pm
There are competitors to FH, both external to SpaceX and internal as well (i.e. a rocket powered by Raptor). FH can't slip forever without risking being overtaken by events....

And if that the best way for them to proceed, then that's fine. They shouldn't have an F9H unless they need one, and event may mean they don't actually need one.

They made FH necessary by announcing Red Dragon.

Good point. Plenty of time then to get it right.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 08/01/2016 02:43 pm
Are there two landing pads ready at Landing Zone 1? 

no
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Donosauro on 08/01/2016 05:23 pm
Is pad 39a ready for Falcon Heavy to launch?  Are there two landing pads ready at Landing Zone 1?  They both have to be ready for a FH launch.

Unless SpaceX decides that flying the FH as soon as possible is more important than recovering both outboard boosters.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: TrueBlueWitt on 08/01/2016 05:30 pm
Is pad 39a ready for Falcon Heavy to launch?  Are there two landing pads ready at Landing Zone 1?  They both have to be ready for a FH launch.

Unless SpaceX decides that flying the FH as soon as possible is more important than recovering both outboard boosters.

Or they could bring the other ASDS from the West coast.. Just saying.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kansan52 on 08/01/2016 06:52 pm
There seems to be nothing so pressing for them to due anything but wait for the Landing Zone is ready for two cores on the LZ and one on the OCISLY.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Torbjorn Larsson, OM on 08/01/2016 11:59 pm
There seems to be nothing so pressing for them to due anything but wait for the Landing Zone is ready for two cores on the LZ and one on the OCISLY.

Out of curiosity, are they forbidden to land two cores at LZ-1 until they have a less risky solution?

Their stated (and shown) landing precision should allow it.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: dorkmo on 08/02/2016 12:31 am
we havent seen any pics of them working on the FH hold down launch deck for the TEL, have we? i feel like thats going to be the biggest clue for launch readiness.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: deruch on 08/02/2016 02:58 am
There seems to be nothing so pressing for them to due anything but wait for the Landing Zone is ready for two cores on the LZ and one on the OCISLY.

Out of curiosity, are they forbidden to land two cores at LZ-1 until they have a less risky solution?

Their stated (and shown) landing precision should allow it.

Yes, they are currently forbidden from simultaneously landing multiple cores at LZ-1.  And that would be the case even if there weren't any technical barriers.  If they want to be allowed to attempt such, whether they alter the pad infrastructure or not, they would need to complete/submit a Supplemental Environmental Assessment--and have it approved/FONSI'd--for landing operations that includes simultaneous landings of multiple boosters at LZ-1.  That option was specifically debarred in their original filing.  If you go back and reread the EA, you'll see that they are quite adamant on the point.  Single booster landings only.  Ergo, they couldn't currently get FAA approval to do it without going through that process first.  At this point, it's not just about the technical challenges it's also the approvals.  And since they have to go through it again regardless of whether they make actual changes on the ground--at least assuming that they want to attempt the dual/ternary landings--then it makes the most sense to do everything at once and get approval for the physical changes they really want over the intermediate term at the same time.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 08/02/2016 09:58 am
Out of interest, what's the minimum time separation before booster landing become 'simultaneous'? Within the hour? Within the minute?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: su27k on 08/02/2016 11:10 am
I remember seeing somewhere that range tracking system needs to be upgraded to support tracking multiple inbound boosters at the same time. Totally unconfirmed rumor, but makes certain amount of sense...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JamesH65 on 08/02/2016 12:32 pm
I remember seeing somewhere that range tracking system needs to be upgraded to support tracking multiple inbound boosters at the same time. Totally unconfirmed rumor, but makes certain amount of sense...

Ah, that makes sense. Need someone to confirm that rumour then!
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: georgegassaway on 08/03/2016 05:13 am
In any case, a slip into 2017, still very much a rumor, is not (or should not) be a surprise to anyone.

True. But..... they have been in this  "6 months from now" pattern since at least April 2015.  It's gotten very old and few real  excuses for it.  They had to know in April 2015 there was no way they could launch in 6 months, and probably not even a year later.   

And also as I said, only NOW have they started to get the paperwork going for LZ-2???  So where were they expecting to land a 2nd FH booster in October 2015,  when even LZ-1 itself was not quite ready?  Does not sound like realistic preparations for launch , as though "6 months from now" slipping about a month every month that goes by, is better than being realistic and truthful with how soon they really expected to fly, by working to have all of the ground support (and landing support) ready 6 months from the announced time. 

Instead,  it looks more like a serial timeline:  Getting the new horizontal assembly hangar at 39-A built first,  THEN many months later work on the pad,  THEN many months later start paperwork for Landing Zone 2 and 3. I mean come on, those should have been happening simultaneously,  in parallel, not one after the other, if they ever truly seriously and realistically planned to launch 6 months after April 2015 (launching October 2015).

This is not typical or unavoidable "slippage".  I won't say what I think it is since I don't know for sure what it is but I have a good idea. But I sure know what it has not been - not a realistic expectation to be launching 6 months later, every time they reset it to about 6 months later (or else FH would have flown long ago). 

I will not be surprised if in December 2016, the first FH flight has slipped to July 2017.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lars-J on 08/03/2016 05:17 am
And also as I said, only NOW have they started to get the paperwork going for LZ-2???

Us hearing about it NOW does not mean that they just got the paperwork going NOW. Not even close, so spare us your ...outrage?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 08/03/2016 05:35 am
In any case, a slip into 2017, still very much a rumor, is not (or should not) be a surprise to anyone.

True. But..... they have been in this  "6 months from now" pattern since at least April 2015.  It's gotten very old and few real  excuses for it.  They had to know in April 2015 there was no way they could launch in 6 months, and probably not even a year later.   

And also as I said, only NOW have they started to get the paperwork going for LZ-2???  So where were they expecting to land a 2nd FH booster in October 2015,  when even LZ-1 itself was not quite ready?  Does not sound like realistic preparations for launch , as though "6 months from now" slipping about a month every month that goes by, is better than being realistic and truthful with how soon they really expected to fly, by working to have all of the ground support (and landing support) ready 6 months from the announced time. 

Instead,  it looks more like a serial timeline:  Getting the new horizontal assembly hangar at 39-A built first,  THEN many months later work on the pad,  THEN many months later start paperwork for Landing Zone 2 and 3. I mean come on, those should have been happening simultaneously,  in parallel, not one after the other, if they ever truly seriously and realistically planned to launch 6 months after April 2015 (launching October 2015).

This is not typical or unavoidable "slippage".  I won't say what I think it is since I don't know for sure what it is but I have a good idea. But I sure know what it has not been - not a realistic expectation to be launching 6 months later, every time they reset it to about 6 months later (or else FH would have flown long ago). 

I will not be surprised if in December 2016, the first FH flight has slipped to July 2017.

Sometimes, it is not prudent imho to automatically assume something from a very limited set of objective outstanding data. This goes for the LZ-2 paperwork stuff.

Regarding FH now. CRS-7, and bringing the FT variant online might have resulted in making FH a lower priority in the last year or so. Moreover, the changes that come in F9 FT inform the FH design. Regarding LZ-2, maybe SpaceX wanted to test their original design for the pad, GSE and processes before moving on and replicating it on Vandy and the Cape.

We don't really know, can only watch the results.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: sdsds on 08/03/2016 06:59 am
Schedule slips are sort of like glasses of wine: it's not about the size of the glass, it's about the flow rate of the wine!

That said there are times -- particularly in a competitive environment -- where it makes sense to slip the date of introduction of a new product, even if the rate of slip is greater than the rate at which time is passing (e.g. slipping the schedule 8 months over the course of 4 months isn't necessarily "wrong.")  A good example is when the feature set needs to change in order for the new product to compete in a changing marketplace.

In this case I suspect FH is slipping because SpaceX has reassessed both an internal competitor (F9FT) and an external competitor (Vulcan).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Semmel on 08/03/2016 07:27 am
I think the schedule for FH has slipped because they can choose to launch on a F9 expendable if the customer gets really pushy. Therefore, they have no schedule pressure on FH, only an economical pressure: expending a F9 core that would have been a recoverable FH. So from SpaceX perspective, there is no incentive to go full speed on FH at great expense. I absolutely believe they could launch FH in 6 Month if they have to and decide to spend the money on infrastructure. As long as they dont have pressure though, I would expect a slow progress that does not eat into their operational budget.

BTW, the only schedule pressure they have put on them selfs: Red Dragon. So I would expect a demo FH flight until late 2017 if Red Dragon does not slip before that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 08/03/2016 07:43 am
I had expected for a while that the wish for Air Force launches would produce schedule pressure. But recently that seems no longer the case?

Edit: I mean the wish to be able to perform launches for the Air Force.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Semmel on 08/03/2016 08:58 am
I had expected for a while that the wish for Air Force launches would produce schedule pressure. But recently that seems no longer the case?

Edit: I mean the wish to be able to perform launches for the Air Force.

Yeah, I had the same hopes, but it does not look like the air force is a driver for them any more. To me, it looks like they snack some DoD launches if it suits them, but not that they go too far out of their way for it. Jims post on vertical integration comes to mind.

@edit: Found it.
Spacex is playing the role of Henry Ford and Model T's (You can get it in any color you want as long as it is black)

You want VI, we have HI
You want longer fairing, we have our fairing
You want fairing doors all over the place, we have our standard door locations
You want a Triple grande non fat decaf iced latte, we have black coffee
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: guckyfan on 08/03/2016 09:04 am
Yeah, I had the same hopes, but it does not look like the air force is a driver for them any more. To me, it looks like they snack some DoD launches if it suits them, but not that they go too far out of their way for it. Jims post on vertical integration comes to mind.

@edit: Found it.
Spacex is playing the role of Henry Ford and Model T's (You can get it in any color you want as long as it is black)

You want VI, we have HI
You want longer fairing, we have our fairing
You want fairing doors all over the place, we have our standard door locations
You want a Triple grande non fat decaf iced latte, we have black coffee

What comes to my mind is that Congress slashed the DoD budget for the flights the Air Force could have offered for bidding. No flights, no interest of SpaceX to be certified.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: the_other_Doug on 08/03/2016 03:07 pm
So -- it's the consensus of all the engineering types around here that SpaceX is deliberately delaying FH for their own internal reasons, and not because they are still addressing potential engineering issues?

No one thinks that strapping together a total of 27 engines, in three different thrust structures and three discrete-but-interacting flight control systems, and igniting all of them for lift-off has any potential engineering challenges that might still be looking for hard solutions?

Just wonderin'... :)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Kabloona on 08/03/2016 03:25 pm
So -- it's the consensus of all the engineering types around here that SpaceX is deliberately delaying FH for their own internal reasons, and not because they are still addressing potential engineering issues?

No one thinks that strapping together a total of 27 engines, in three different thrust structures and three discrete-but-interacting flight control systems, and igniting all of them for lift-off has any potential engineering challenges that might still be looking for hard solutions?

Just wonderin'... :)

Not to mention the manpower/schedule challenge of trying to catch up on a severe F9 launch backlog...and getting crewed Dragon done, which has also been slipping, BTW...

Their workload has been increasing at a rapid rate, and increasing staffing to match in an extremely demanding work environment like that can be very difficult to manage. Often the hiring lags behind the actual headcount need. We've already heard that 80-hour work weeks are common. It wouldn't surprise me if the delays in FH and crewed Dragon are simply the result of too few people trying to do too much work.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: the_other_Doug on 08/03/2016 03:45 pm
So -- it's the consensus of all the engineering types around here that SpaceX is deliberately delaying FH for their own internal reasons, and not because they are still addressing potential engineering issues?

No one thinks that strapping together a total of 27 engines, in three different thrust structures and three discrete-but-interacting flight control systems, and igniting all of them for lift-off has any potential engineering challenges that might still be looking for hard solutions?

Just wonderin'... :)

Not to mention the manpower/schedule challenge of trying to catch up on a severe F9 launch backlog...and getting crewed Dragon done, which has also been slipping, BTW...

Their workload has been increasing at a rapid rate, and increasing staffing to match in an extremely demanding work environment like that can be very difficult to manage. Often the hiring lags behind the actual headcount need. We've already heard that 80-hour work weeks are common. It wouldn't surprise me if the delays in FH and crewed Dragon are simply the result of too few people trying to do too much work.

Oh, sure -- totally understood.  "Manning up" for big sets of work events is always a challenge.

It's not just a matter of wanting to run "lean and mean," and thus keeping your costs down, either.  Sometimes the amount of work that needs to be done, especially on new development programs, mushrooms in ways you never expect and would have had a hard time predicting.  During Apollo (my main knowledge base era, as y'all know), for example, Grumman bid for the LM based on a certain anticipated workforce requirement over the course of the program.  They woefully underestimated the need for labor in many, many areas, especially early in the design process when they had far fewer people available than needed to create the drawings of the systems needed to proceed into production.  A simple lack of people to create engineering drawings, more than anything else, delayed progress on the LM for well more than a year, and wasn't fully resolved until the customer (NASA) came in and told them where they needed to beef up their labor force...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Arb on 08/03/2016 04:20 pm
Another possibility (and the most likely imo) is that they are waiting for F9 booster recovery to be essentially solved so they can incorporate into the first FH all the changes they must be discovering are needed to allow reuse with minimal refurbishment.

Three x $20-30 million is way too much for them to willingly throw away on that first[1], self funded (apparently) test flight.

[1] or indeed on any flight.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 08/03/2016 04:42 pm

No one thinks that strapping together a total of 27 engines, in three different thrust structures and three discrete-but-interacting flight control systems, and igniting all of them for lift-off has any potential engineering challenges that might still be looking for hard solutions?

No,
a.  They haven't have any issues for 9 engine starts for awhile.  Doing 27, it isn't going to change much
b.  They aren't 3 different, but two exactly the same,with the other similar.
c.  Flight control systems are any different.  They are all slaved to the second stage until after separation, just like a single stick launch.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: the_other_Doug on 08/03/2016 05:00 pm

No one thinks that strapping together a total of 27 engines, in three different thrust structures and three discrete-but-interacting flight control systems, and igniting all of them for lift-off has any potential engineering challenges that might still be looking for hard solutions?

No,
a.  They haven't have any issues for 9 engine starts for awhile.  Doing 27, it isn't going to change much
b.  They aren't 3 different, but two exactly the same,with the other similar.
c.  Flight control systems are any different.  They are all slaved to the second stage until after separation, just like a single stick launch.

Thanks, Jim!  To clarify, I wasn't trying to suggest that SpaceX must be having problems in integrating the three cores that they're not talking about.  I was just tossing out a couple of examples of the kinds of things one might think would need to be explored and addressed.

Glad to hear, from someone who knows, that there seem to be no insurmountable engineering issues to be solved before they strap three of these things together and light 'em all off.  And thanks for the reminder that the three boost stages will be slaved to the FCS in stage 2 until they separate.

I know the separate FCS systems in each booster are identical (with possibly small alterations to the center core's FCS), but I've seen two (granted, commercial) identical GPS receivers sitting side-by-side disagree in their position by several meters.  Obviously, the side boosters on each FH launch will have to be in very close agreement on their position, both via GPS and inertial, once their separate flight control systems take over upon separation.

Also, the side cores will need to fly avoidance maneuvers to ensure no recontact with either the remaining center core, or each other, that initiate immediately upon side booster separation, etc. -- all I was suggesting is that these are things SpaceX has never done before, and that have never been done with this specific booster, and I wondered if they would pose engineering challenges that could still be in the process of being addressed.

Good to know, as you seem to intimate, that these will not be show-stoppers.  I'm hoping SpaceX isn't working any other show-stoppers on the engineering side -- it's not like they would be publicizing it, if they were.

I do still wonder about Elon stating the two side boosters will RTLS "nearly simultaneously."  I'd think you would want to maintain some distance between the two stages, to avoid any possibility of interaction between the two.  Each stage is generating sonic booms, after all -- I wouldn't think you'd want them within a kilometer of each other when they each go subsonic.  A little separation, please...?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 08/03/2016 05:24 pm
1.    Obviously, the side boosters on each FH launch will have to be in very close agreement on their position, both via GPS and inertial, once their separate flight control systems take over upon separation.

2.  Also, the side cores will need to fly avoidance maneuvers to ensure no recontact with either the remaining center

1.  Not really, they already are further apart than the standard GPS error and they will never get closer.

2.  Not really, they will be separated by solid motors and/or gas thrusters (just like other vehicles).  Just as the single core booster doesn't do anything right after separation, neither will the side boosters.  Aerodynamics will take over as the booster angle away and increase the separation.


  Each stage is generating sonic booms, after all -- I wouldn't think you'd want them within a kilometer of each other when they each go subsonic.  A little separation, please...?

That should have no bearing on the matter. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Dante80 on 08/03/2016 05:50 pm
2.  Not really, they will be separated by solid motors and/or gas thrusters (just like other vehicles).  Just as the single core booster doesn't do anything right after separation, neither will the side boosters.  Aerodynamics will take over as the booster angle away and increase the separation.

Do we have any more info on this procedure? I think that SpaceX would use a hydraulic system initially for separation, and maybe couple it with the nitrogen thrusters for adding some distance after that.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Jim on 08/03/2016 05:53 pm
2.  Not really, they will be separated by solid motors and/or gas thrusters (just like other vehicles).  Just as the single core booster doesn't do anything right after separation, neither will the side boosters.  Aerodynamics will take over as the booster angle away and increase the separation.

Do we have any more info on this procedure? I think that SpaceX would use a hydraulic system initially for separation, and maybe couple it with the nitrogen thrusters for adding some distance after that.

Gas thrusters/gas pistons   

A large impulse is needed.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: the_other_Doug on 08/03/2016 05:59 pm
2.  Not really, they will be separated by solid motors and/or gas thrusters (just like other vehicles).  Just as the single core booster doesn't do anything right after separation, neither will the side boosters.  Aerodynamics will take over as the booster angle away and increase the separation.

Do we have any more info on this procedure? I think that SpaceX would use a hydraulic system initially for separation, and maybe couple it with the nitrogen thrusters for adding some distance after that.

Gas thrusters/gas pistons   

A large impulse is needed.

Have side boosters (LRB or SRB) on any large rockets ever been jettisoned with anything except explosive bolts and solid-fuel separation motors?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Silmfeanor on 08/03/2016 06:24 pm
2.  Not really, they will be separated by solid motors and/or gas thrusters (just like other vehicles).  Just as the single core booster doesn't do anything right after separation, neither will the side boosters.  Aerodynamics will take over as the booster angle away and increase the separation.

Do we have any more info on this procedure? I think that SpaceX would use a hydraulic system initially for separation, and maybe couple it with the nitrogen thrusters for adding some distance after that.

Gas thrusters/gas pistons   

A large impulse is needed.

Have side boosters (LRB or SRB) on any large rockets ever been jettisoned with anything except explosive bolts and solid-fuel separation motors?
Soyuz boosters just drop away and vent some gas near the top I think; no solids involved.

a thread about it can be found here:
https://forum.nasaspaceflight.com/index.php?topic=12437.0
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 08/03/2016 06:30 pm
So -- it's the consensus of all the engineering types around here that SpaceX is deliberately delaying FH for their own internal reasons, and not because they are still addressing potential engineering issues?

No one thinks that strapping together a total of 27 engines, in three different thrust structures and three discrete-but-interacting flight control systems, and igniting all of them for lift-off has any potential engineering challenges that might still be looking for hard solutions?

Just wonderin'... :)

Not to mention the manpower/schedule challenge of trying to catch up on a severe F9 launch backlog...and getting crewed Dragon done, which has also been slipping, BTW...

Their workload has been increasing at a rapid rate, and increasing staffing to match in an extremely demanding work environment like that can be very difficult to manage. Often the hiring lags behind the actual headcount need. We've already heard that 80-hour work weeks are common. It wouldn't surprise me if the delays in FH and crewed Dragon are simply the result of too few people trying to do too much work.

I think a likely reason for the FH delay is exactly what you mentioned.  The F9 backlog of paying customers who have been waiting a long time.

Resources, such as people, money and equipment, being stretched by other projects like Dragon (that will generate large revenues).

Waiting until recovery is understood a little more and increases the likelihood of being successful in recovering all 3 boosters. 

I want to see the FH fly, it's going to be a crazy machine, and I have been critical of SpaceX's delays and schedule slips.  But this one doesn't trouble me that much.  It's getting closer, there is hardware and I don't believe there is a design or engineering hold up, just getting it through the system.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 08/03/2016 06:52 pm
I remember seeing somewhere that range tracking system needs to be upgraded to support tracking multiple inbound boosters at the same time. Totally unconfirmed rumor, but makes certain amount of sense...

Ah, that makes sense. Need someone to confirm that rumour then!
Since Shuttle in the 1980's both ranges needed capability to track and have backups for three simultaneous objects which not only was radar but 3 independent telemetry streams with additional backup telemetry receiver station or stations. With the F9/FH as well as other LVs going forward with AFTS the critical of radar drops such that each object must be able to be tracked by a combination of radar or telemetry assets not both with backups. Less assets but an FH still has more range assets required than a F9 creating a launch constraint more sensitive to range assets health than for F9.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: FutureSpaceTourist on 08/09/2016 05:18 pm
Quote
Shotwell on Falcon Heavy: “sorry we’re late” on it; harder problem to develop than we thought. #smallsat

https://twitter.com/jeff_foust/status/763060905886167040 (https://twitter.com/jeff_foust/status/763060905886167040)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Shanuson on 08/09/2016 05:46 pm
Quote
David Hurst
‏@OrbitalDave

Shotwell: 1st Falcon Heavy mission expected Q3 of 17 #smallsat

https://twitter.com/OrbitalDave/status/763060858528215040

The guy posting from the conference on Reddit said that's the STP-2 mission in Q3 2017, which would be the second or third FH flight.  Can't wait until they post a video of the talk so we don't have to rely on a bunch of possibly misleading tweets.

I think you are right that the qualification flight will be before that and she did not mean the first F9H flight with her comment.
Still have the feeling F9H shifts right one month each month. Has someone already collected data on that feeling?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cebri on 08/09/2016 07:03 pm
Ok. I asked jeff foust. Demo still planned for late this year, early next. However delay in the FH development pushing other missions forward.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Mike_1179 on 08/23/2016 05:38 pm
Is it useful to create a FH with three cores that might not be the final design (how to jettison side boosters, flight software, thermal protection, etc.) to test out the GSE? Is there a benefit to getting a WDR done without waiting for the boosters and core to be complete?
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: oldAtlas_Eguy on 08/23/2016 09:55 pm
Is it useful to create a FH with three cores that might not be the final design (how to jettison side boosters, flight software, thermal protection, etc.) to test out the GSE? Is there a benefit to getting a WDR done without waiting for the boosters and core to be complete?
SpaceX adopted mantra "Test as you fly. Fly as you test." So no. Only if the use will gain them something very significant is the only exception. The only exception that comes to mind is that the M1D FTs are not yet the M1D maxFTs. M1D max FTs are to supposed start being used sometime after Oct on F9.

But this is not to say that they will not tweak the designs once the FH starts flying either. Its just that intentionally not flying the current design is not likely to gain them anything. A BTW on the engines is that their impact if the non maxFT ones are used is use of different constants in the software and a smaller payload but not much else.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 08/25/2016 07:40 pm
I realized that, with latest improvements of M1D, FH would still have a good T/W at liftoff with a five engine center core.
This would be 2000 kg dry mass reduction; not saying it is simple, but improving mass ratio on the center core would be a very good thing for reusability.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Nomadd on 08/25/2016 07:46 pm
I realized that, with latest improvements of M1D, FH would still have a good T/W at liftoff with a five engine center core.
This would be 2000 kg dry mass reduction; not saying it is simple, but improving mass ratio on the center core would be a very good thing for reusability.
The lighter the core, the more overpowered the last part of the landing. They can do it, but the benefit might be marginal compared to the job of designing a different stage. it might also cost them engine out capabilty for much of the flight.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: cambrianera on 08/25/2016 08:06 pm
The lighter the core, the more overpowered the last part of the landing.
Can't follow your logic, mass reduction is a good thing, and SpaceX seems perfectly capable of landing a stage with about 10% reduced mass compared to actual.

They can do it, but the benefit might be marginal compared to the job of designing a different stage.
Center core already is a different stage, and about 10% reduced mass seems not marginal to me.
Less engines means also less cost.


It might also cost them engine out capabilty for much of the flight.
Losing 1/23 is not that different than losing 1/29.
Maybe losing 1/5 is, compared to 1/9.
No free lunch anyway...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 08/25/2016 08:11 pm
Is it useful to create a FH with three cores that might not be the final design (how to jettison side boosters, flight software, thermal protection, etc.) to test out the GSE? Is there a benefit to getting a WDR done without waiting for the boosters and core to be complete?
SpaceX adopted mantra "Test as you fly. Fly as you test." So no. Only if the use will gain them something very significant is the only exception. The only exception that comes to mind is that the M1D FTs are not yet the M1D maxFTs. M1D max FTs are to supposed start being used sometime after Oct on F9.

But this is not to say that they will not tweak the designs once the FH starts flying either. Its just that intentionally not flying the current design is not likely to gain them anything. A BTW on the engines is that their impact if the non maxFT ones are used is use of different constants in the software and a smaller payload but not much else.

Agreed with OAG.  Using a test article is something you do if you have time and money to burn.  Modern design tools and computer modeling have eased or eliminated many of the things that a test article would be used to evaluate.  Design, fabrication and testing has improved ridiculously, I'm constantly in awe.

SpaceX is flying a similar vehicle and learning each flight.  The FH will require some new steps but nothing that can't be figured out with flight hardware.

After seeing the returned core with what appears to be no engines I started to think that maybe the FH slip is partly so that it only ever flies with the maxFT engines. 

SpaceX is likely planning to reuse this first FH a number of times as nothing up to Red Dragon needs expendable performance.  May as well be the final configuration.  Heck this first FH maybe the Red Dragon vehicle.

Edit: My bad, I just remembered I was 'corrected' a while ago by others saying that the Red Dragon FH was going to be recovered. 
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 08/25/2016 08:14 pm
Direct GSO insertion of large sats needs expendable performance (and 2nd stage endurance). I know they have said they are working on the endurance, but don't think they have any direct GSO payloads manifested.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 08/25/2016 08:24 pm
Direct GSO insertion of large sats needs expendable performance (and 2nd stage endurance). I know they have said they are working on the endurance, but don't think they have any direct GSO payloads manifested.
I think you underestimate just how powerful Falcon Heavy is even in partially reusable mode. Yes, even for high energy missions...
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Roy_H on 08/26/2016 11:42 pm
I suspect that SpaceX will not quote on any GSO missions until they have the Raptor/methane upper stage operational. I just can't see them committing resources for an interim solution that would only be used for a few flights.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: wannamoonbase on 08/27/2016 12:14 am
I suspect that SpaceX will not quote on any GSO missions until they have the Raptor/methane upper stage operational. I just can't see them committing resources for an interim solution that would only be used for a few flights.

Well, that all depends on how much they can make on those few flights.

Also, if it can 'bolt on' to a Raptor US then they can jump right into the market with that. 

PS: I'm super excited about the possibility of a Raptor US.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: envy887 on 08/27/2016 12:53 am
Direct GSO insertion of large sats needs expendable performance (and 2nd stage endurance). I know they have said they are working on the endurance, but don't think they have any direct GSO payloads manifested.
I think you underestimate just how powerful Falcon Heavy is even in partially reusable mode. Yes, even for high energy missions...
If they expend the center core, sure. But that's not really compatible with keeping one set of Heavy-specific hardware flying multiple times.

But the customers that would demand direct GSO insertion would probably also want a new launcher and be more than willing to pony up an extra $150 million.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Robotbeat on 08/27/2016 02:29 am
I suspect that SpaceX will not quote on any GSO missions until they have the Raptor/methane upper stage operational. I just can't see them committing resources for an interim solution that would only be used for a few flights.
...this depends on whether or not SpaceX will deploy a Raptor-based upper stage for Falcon. That's not entirely certain right now.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Ronsmytheiii on 08/27/2016 09:25 am
I suspect that SpaceX will not quote on any GSO missions until they have the Raptor/methane upper stage operational. I just can't see them committing resources for an interim solution that would only be used for a few flights.
...this depends on whether or not SpaceX will deploy a Raptor-based upper stage for Falcon. That's not entirely certain right now.

Considering the fact that they have an Air Force Contract to do exactly that, I am not sure why they wouldn't:

http://www.parabolicarc.com/2016/01/18/spacex-air-force-funding-infusion-raptor-engine/

Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mfck on 08/27/2016 09:43 am
I suspect that SpaceX will not quote on any GSO missions until they have the Raptor/methane upper stage operational. I just can't see them committing resources for an interim solution that would only be used for a few flights.
...this depends on whether or not SpaceX will deploy a Raptor-based upper stage for Falcon. That's not entirely certain right now.

Considering the fact that they have an Air Force Contract to do exactly that, I am not sure why they wouldn't:

http://www.parabolicarc.com/2016/01/18/spacex-air-force-funding-infusion-raptor-engine/
It's a contract for a prototype engine, not a US
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: MATTBLAK on 08/27/2016 09:46 am
And to think; when in earlier threads I said that the Falcon family was going to get a Raptor powered upper stage, there were some who said it simply wasn't going to happen, or that I didn't know what I was talking about... ;)
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Ronsmytheiii on 08/27/2016 09:52 am

It's a contract for a prototype engine, not a US

The engine is pretty much all of the upperstage, stop splitting hairs when it is meaningless
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mfck on 08/27/2016 09:59 am
It's a contract for a prototype engine, not a US

It is a prototype for an upperstage engine:

Quote
Space Exploration Technologies, Corp. (SpaceX), Hawthorne, California, has been awarded a $33,660,254 other transaction agreement for the development of the Raptor rocket propulsion system prototype for the Evolved Expendable Launch Vehicle (EELV) program. This agreement implements Section 1604 of the Fiscal Year 2015 National Defense Authorization Act, which requires the development of a next-generation rocket propulsion system that will transition away from the use of the Russian-supplied RD-180 engine to a domestic alternative for National Security Space launches. An other transaction agreement was used in lieu of a standard procurement contract in order to leverage on-going investment by industry in rocket propulsion systems. This other transaction agreement requires shared cost investment with SpaceX for the development of a prototype of the Raptor engine for the upper stage of the Falcon 9 and Falcon Heavy launch vehicles. The locations of performance are NASA Stennis Space Center, Mississippi; Hawthorne, California; and Los Angeles Air Force Base, California. The work is expected to be completed no later than Dec. 31, 2018. Air Force fiscal 2015 research, development, test and evaluation funds in the amount of $33,660,254 are being obligated at the time of award.  SpaceX is contributing $67,320,506 at the time of award. The total potential government investment, including all options, is $61,392,710. The total potential investment by SpaceX, including all options, is $122,785,419. This award is the result of a competitive acquisition with multiple offers received. The Launch Systems Enterprise Directorate, Space and Missile Systems Center, Los Angeles Air Force Base, California is the contracting activity (FA8811-16-9-0001).

So you think SpaceX would design a prototype engine for Falcon 9/Heavy, and immediately shelve it? I can't see them doing that, if the engine is available and its will make money (for their Mars efforts) why would SpaceX not use it? Methane isnt that different from the operating temperatures for the low density LOX, it wont be that hard to design a tank for the engine.

http://www.defense.gov/News/Contracts/Contract-View/Article/642983
It is not obvious, that the business case for such a change in F9/FH closes at this time. Mind you, I am not saying they won't do it, just that the contract is not for a US. On the contrary, I have even made a WAG prediction, here or on one of the other threads, that the new US for FH will be announced 18 months after first commercial FH flight. Got laughed at by Jim.

DoD payloads do not seem to be high priority for SX. They use AF as a disruption amplifier, not as anchor client, imo.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mfck on 08/27/2016 10:02 am

It's a contract for a prototype engine, not a US

The engine is pretty much all of the upperstage, stop splitting hairs when it is meaningless
I am not splitting anything. Integrarion, GSE and testing are all going to cost extra for a new stage.
Edit, for clarity: Meaning, building a new US and fielding a new US is not the same, especially when one of the highest stated priorities for SX is launch cadence.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Ronsmytheiii on 08/27/2016 10:11 am

It's a contract for a prototype engine, not a US

The engine is pretty much all of the upperstage, stop splitting hairs when it is meaningless
I am not splitting anything. Integrarion, GSE and testing are all going to cost extra for a new stage.

But SpaceX and the Air Force are going to spend at least $67 Million and $33.7 million respectively on an engine that will be shelved? All of the things you listed SpaceX did when they upgraded Falcon 9 for FT, yes it is extra but well less than a new engine.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: mfck on 08/27/2016 10:13 am



It's a contract for a prototype engine, not a US

The engine is pretty much all of the upperstage, stop splitting hairs when it is meaningless
I am not splitting anything. Integrarion, GSE and testing are all going to cost extra for a new stage.

But SpaceX and the Air Force are going to spend at least $67 Million and $33.7 million respectively on an engine that will be shelved? All of the things you listed SpaceX did when they upgraded Falcon 9 for FT, yes it is extra but well less than a new engine.

It is hardly the same to me, but IANAE. And I have not said a word about shelving. There is this BFS talk, you might have heard.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rsdavis9 on 08/27/2016 10:49 am
I might have to agree with the fact that the mix of methane and kerosene on the same rocket is going to make it harder for the gse equipment. Waiting for bfs could well be the better choice from methane only gse and not complicating the launch cadence. Launching often is where spacex is really making money. I.E. spreading fixed cost over many launches. DOD really slows them down in this respect.

EDIT: changed gso to gse.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: JBF on 08/27/2016 11:12 am

It's a contract for a prototype engine, not a US

The engine is pretty much all of the upperstage, stop splitting hairs when it is meaningless
I am not splitting anything. Integrarion, GSE and testing are all going to cost extra for a new stage.

But SpaceX and the Air Force are going to spend at least $67 Million and $33.7 million respectively on an engine that will be shelved? All of the things you listed SpaceX did when they upgraded Falcon 9 for FT, yes it is extra but well less than a new engine.

To the AF 37mil is chump change.  SpaceX could be doing this just as a chance to get someone else to help pay for raptor development.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: GORDAP on 08/27/2016 11:19 am

It's a contract for a prototype engine, not a US

The engine is pretty much all of the upperstage, stop splitting hairs when it is meaningless
I am not splitting anything. Integrarion, GSE and testing are all going to cost extra for a new stage.

But SpaceX and the Air Force are going to spend at least $67 Million and $33.7 million respectively on an engine that will be shelved? All of the things you listed SpaceX did when they upgraded Falcon 9 for FT, yes it is extra but well less than a new engine.

Ron, you may have missed it, but Musk recently (a month or so back) said that, while it is tempting to now jump into designing a new US for the Falcons based on the Raptor, it would compete for resources with 'the Mars rocket'.  And that they need to get busy on the latter.

So indeed it does look as though they are 'shelving' plans for a Raptor based US for the Falcons (but not for a US Raptor itself).
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: rsdavis9 on 08/27/2016 11:38 am
https://twitter.com/elonmusk/status/755167487017291776
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Chris Bergin on 08/27/2016 04:50 pm
Thread 5:
https://forum.nasaspaceflight.com/index.php?topic=41019.0
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: gongora on 08/29/2016 03:46 pm
Reminder, you should be posting in Thread 5 now.  Chris was kind enough to not lock the old threads this time so we can still quote them.
Title: Re: SpaceX Falcon Heavy Discussion (Thread 4)
Post by: Lar on 08/29/2016 04:27 pm
Reminder, you should be posting in Thread 5 now.  Chris was kind enough to not lock the old threads this time so we can still quote them.
Indeed.

I splitmerged the posts over to 5. Next time I may just delete them because I'm super mean that way.