It's important to remember than Elon Musk is a dot-com billionaire. He comes from an industry where vaporware is not only endemic but most required as a business plan. So all this talk about future rockets FX, FXH and FXX is just that: talk.As for the Merlin2. Right now the DOD is interested in a 500K rocket engine. I think that's what we're going to see a 500K (possibly methane) engine.But people should take the things Musk says with a grain of salt.
First you need an engine development. The only new engine development is the SC engine of unknown thrust and unknown prop type. With a 300-500klbf RP-1/LOX engine using the same 9:1 configuration a vehicle with the same length and 5-6m diameter which can be launched initially on the same pads as F9, a greater than double performance of the F9/FH or 30-35MT/105-125MT can be achieved at roughly the same prices or up to 50% more as that of the F9/FH. This would drop LEO $/kg rates by about 30% or to $3,500/$1,800 for single/heavy. This approach would use the experience gained from the F9 and FH and just scale up those designs including being able to use the RLV concepts being explored for the F9. A 1+mlbf engine as the next engine just does not seem to be in the near future plans.Such a vehicle would replace the FH usage completely leaving the F9 as the small sat launcher then the X vehicle as the large GEO sat launcher and then the XH vehicle as a BEO or tanker launcher.
Quote from: beb on 11/11/2011 02:59 pmIt's important to remember than Elon Musk is a dot-com billionaire. He comes from an industry where vaporware is not only endemic but most required as a business plan. So all this talk about future rockets FX, FXH and FXX is just that: talk.As for the Merlin2. Right now the DOD is interested in a 500K rocket engine. I think that's what we're going to see a 500K (possibly methane) engine.But people should take the things Musk says with a grain of salt. When was the last time you saw Musk talking about those? Musk wasn't the one really pushing FX, FXX, Merlin 2 etc. That's pretty much just SpaceX amazing people, plus a couple powerpoints from SpaceX. Musk has been pushing crewed Dragon, reusable Falcon 9, and Falcon Heavy. Ambitious enough.
Discuss the possibility of a Falcon X, Falcon X Heavy, Falcon XX, and Merlin 2 engine.
Quote from: beb on 11/11/2011 02:59 pmIt's important to remember than Elon Musk is a dot-com billionaire. He comes from an industry where vaporware is not only endemic but most required as a business plan. So all this talk about future rockets FX, FXH and FXX is just that: talk.As for the Merlin2. Right now the DOD is interested in a 500K rocket engine. I think that's what we're going to see a 500K (possibly methane) engine.But people should take the things Musk says with a grain of salt. Uh, didn't Musk actually come out and say specifically they weren't building an FX, FXH or FXX, and that he was annoyed they'd been publicly discussed at all?So this isn't something Musk said that we should take with a grain of salt, this is something Musk specifically denied that fans and detractors alike have taken way too seriously.
“we’re confident we could get a fully operational vehicle to the pad for $2.5 billion—and not only that, I will personally guarantee it,” Musk says. In addition, the final product would be a fully accounted cost per flight of $300 million, he asserts. “I’ll also guarantee that,” he adds, though he cautions this does not include a potential upper-stage upgrade.
Quote from: ArbitraryConstant on 11/11/2011 05:24 pmQuote from: beb on 11/11/2011 02:59 pmIt's important to remember than Elon Musk is a dot-com billionaire. He comes from an industry where vaporware is not only endemic but most required as a business plan. So all this talk about future rockets FX, FXH and FXX is just that: talk.As for the Merlin2. Right now the DOD is interested in a 500K rocket engine. I think that's what we're going to see a 500K (possibly methane) engine.But people should take the things Musk says with a grain of salt. Uh, didn't Musk actually come out and say specifically they weren't building an FX, FXH or FXX, and that he was annoyed they'd been publicly discussed at all?So this isn't something Musk said that we should take with a grain of salt, this is something Musk specifically denied that fans and detractors alike have taken way too seriously.Than he probably shouldn't have said this Quote“we’re confident we could get a fully operational vehicle to the pad for $2.5 billion—and not only that, I will personally guarantee it,” Musk says. In addition, the final product would be a fully accounted cost per flight of $300 million, he asserts. “I’ll also guarantee that,” he adds, though he cautions this does not include a potential upper-stage upgrade.
With IPO money also comes a greater fiduciary responsibility. That means expensive projects with little reason and little chance of real payback ever will be actually less likely for SpaceX to take on than they are now. I can imagine IPO money being used for Merlin 2 MAYBE, but not the other vehicles beyond Falcon Heavy, since there's really no market need, not even close.
And everyone will get a pony too.
After reading articlehttp://www.aviationweek.com/aw/generic/story_channel.jsp?channel=space&id=news/awst/2010/11/29/AW_11_29_2010_p28-271784.xmlThat is if the FXX were ever built, could a clean 39A or 39B pad handle the FXX on it's own MLP? (I assume that RP-1 fuel tanks would be there)
Quote from: RocketmanUS on 11/11/2011 11:00 pmAfter reading articlehttp://www.aviationweek.com/aw/generic/story_channel.jsp?channel=space&id=news/awst/2010/11/29/AW_11_29_2010_p28-271784.xmlThat is if the FXX were ever built, could a clean 39A or 39B pad handle the FXX on it's own MLP? (I assume that RP-1 fuel tanks would be there)Of course. Imaginary launch vehicles work on imaginary pads.
Serious answer please.Based on expected size of FXX ( diameter ) and fueled and unfueled could the pad handle it? The flame trench would it work with such a vehicle?
Than he probably shouldn't have said this Quote“we’re confident we could get a fully operational vehicle to the pad for $2.5 billion—and not only that, I will personally guarantee it,” Musk says. In addition, the final product would be a fully accounted cost per flight of $300 million, he asserts. “I’ll also guarantee that,” he adds, though he cautions this does not include a potential upper-stage upgrade.
The Merlin 2 as I understand it was to have two settings, 1.2Mlb or 1.7Mlb at launch. The 1.2Mlb was for FX,FXH and the 1.7Mlb setting for the FXX. So the Merlin 2 would have plenty of thrust for a reusable Falcon.
If you want insight into their aspirations, wait for more details on the staged combustion engine they've been talking about.
This is becoming a farcical, predicting all these wild SpaceX projects, when the company is still a long way off from ...
2012 will be the year SpaceX has to show that they can fire more than 1 rocket a year...
Quote from: apace on 11/12/2011 03:57 pm2012 will be the year SpaceX has to show that they can fire more than 1 rocket a year... I thought that about 2011 as well (in fact there are still five 2011 flights on the manifest).
Quote from: oldAtlas_Eguy on 11/11/2011 04:18 pmFirst you need an engine development. The only new engine development is the SC engine of unknown thrust and unknown prop type. With a 300-500klbf RP-1/LOX engine using the same 9:1 configuration a vehicle with the same length and 5-6m diameter which can be launched initially on the same pads as F9, a greater than double performance of the F9/FH or 30-35MT/105-125MT can be achieved at roughly the same prices or up to 50% more as that of the F9/FH. This would drop LEO $/kg rates by about 30% or to $3,500/$1,800 for single/heavy. This approach would use the experience gained from the F9 and FH and just scale up those designs including being able to use the RLV concepts being explored for the F9. A 1+mlbf engine as the next engine just does not seem to be in the near future plans.Such a vehicle would replace the FH usage completely leaving the F9 as the small sat launcher then the X vehicle as the large GEO sat launcher and then the XH vehicle as a BEO or tanker launcher.How about they finish the development of the FH first ? Any idea on how much SpaceX has committed to the development of the FH, before you go and obsolete it before the first flight ? How much was spent to develop the F1, only to halt production after 5 flights ? Eventually, you need to launch production rockets enough times to pay for the development costs. NASA and/or the DOD will not be funding this development.
F9 is already in active production... it's launch operations that is lagging.
I woulod say that FX can be considered a competitor to the equally paper-only Atlas-V P2/3A and FXX to the Atlas-V P3B.Both FXX and Atlas-V P3B could be considered commercial alternatives to the SLS as they both fall into the same performance category (70-150t IMLEO and >25t through escape). Both FX and A-V P2/3A fit in my 'General Purpose Launch Vehicle' concept that can be optimised for any HSF application from CLV to heavy CaLV (20-100t+ IMLEO). I believe that it could be possible to have fully-reusable CCBs for both FX and A-V P2/3A; SpaceX have outlined one way to make the upper stage reusable too.But, as tigerade rightly points out, neither are seriously in development. They're just concepts right now and, with NASA and its Congressional supporters politically and ideologically committed to SLS, they are not likely to move into serious development any time soon.
And until F9 has a record behind it, one mishap could destroy that company.
Also with propellant cross feed they have growth capacity from 3 to 5, 7 or even 9 parallel stages by simply beefing up center stage structure. That gives LEO capacity of up to 150 tonnes (higher than FXX), while lower initial staging velocities for 5-9 stage variants makes recovery of at least some of those stages even easier.
If SpaceX can make Merlin 2 they can put everybody out of business.
Quote from: spectre9 on 11/17/2011 01:01 pmIf SpaceX can make Merlin 2 they can put everybody out of business.Not so. Only reusability could do that.
Quote from: go4mars on 11/17/2011 02:11 pmQuote from: spectre9 on 11/17/2011 01:01 pmIf SpaceX can make Merlin 2 they can put everybody out of business.Not so. Only reusability could do that.FWIW, I believe propulsive reusability is incompatible with M2's enormous thrust (1.7Mlbf target, IIRC). ...
Why the heck would you think that?I mean don't get me wrong, I don't think SpaceX is going down the Merlin 2 road, there's just no reason large thrust would mean no reusability.
Quote from: RobLynn on 11/17/2011 11:16 amAlso with propellant cross feed they have growth capacity from 3 to 5, 7 or even 9 parallel stages by simply beefing up center stage structure. That gives LEO capacity of up to 150 tonnes (higher than FXX), while lower initial staging velocities for 5-9 stage variants makes recovery of at least some of those stages even easier.That make less to no sense. The pad infrastructure and operations would be a unwieldy kludge.
Quote from: Jim on 11/17/2011 12:05 pmQuote from: RobLynn on 11/17/2011 11:16 amAlso with propellant cross feed they have growth capacity from 3 to 5, 7 or even 9 parallel stages by simply beefing up center stage structure. That gives LEO capacity of up to 150 tonnes (higher than FXX), while lower initial staging velocities for 5-9 stage variants makes recovery of at least some of those stages even easier.That make less to no sense. The pad infrastructure and operations would be a unwieldy kludge.Why would do think that? You have effectively a single linked fuel a nd oxidiser system through all of the cross feeds (Assuming each engine has shut off valves in case of failure), load bearing connections between stages that can take axial loads of up to 400 tonnes, and so substantial lateral loads as well. It would not be hard to make a cradle to allow horizontal transport and errection even for 9 linked stages if there was demand.I also can't see how supporting the fueled stack weight before liftoff would present any difficulties and while there are other electrical systems and fluids that need to be topped off, most of those will be accessible from the bottom of the stack.
9 stages in a row? It won't know where to fly81 engines on a first stage is ido itic. The hangar and launch mount? And if you meant parallel staged and a circular vehicle, see #2 and forget horizontal processing.
It would not be hard to make a cradle to allow horizontal transport and errection even for 9 linked stages if there was demand.
1. They're supposedly designed to fail safe without damaging other engines. 2. Horizontal integration is harder, but still pretty straight forward given a few simple platforms to walk around on.3. I guess if you don't like it we'll just have to agree to disagree and see how spaceX's plans evolve over next 5 years.
Quote from: Robotbeat on 11/17/2011 02:30 pmWhy the heck would you think that?I mean don't get me wrong, I don't think SpaceX is going down the Merlin 2 road, there's just no reason large thrust would mean no reusability.The M2 has to much thrust for boost back. You would need a secondary (more weight) propulsion system to do the landing at a lower thrust setting.
They are not going to use more than 3 cores.
Quote from: Jim on 11/17/2011 09:10 pmThey are not going to use more than 3 cores.Probably, but 5 might not be inconceivable, integrated in an X configuration like Soyuz with the strongback supporting the central stage only. It's unlikely, though. If SpaceX had any inclination to support a five-core X configuration at some point, then one would expect them to account for that during their refurbishment of SLC-4E.I think that SpaceX likes the economics of cranking out lots of M1 engines on a high-rate production line. I'm not sure we'll see a Falcon 16 or anything like that, but I doubt we'll see less than 4 engines on any future first stage from SpaceX.I also suspect that SpaceX is eyeing NOFBX. Probably for Dragon, but possibly also for future LV stages.
If the SLS goes bust, maybe SpaceX can purchase the 8.4m tooling for scrap, including the barge to transport, and build a 52 M1D engined HLV using a LOX/LH2 US which could do about 95MT in the single stick configuration with a 10m faring or 380MT in the heavy configuration. Talking about BFRs!! Although managing 150+ number of engines maybe a little too much. 52 M1D’s is 7.28mlbf.
Quote from: oldAtlas_Eguy on 11/18/2011 06:16 pmIf the SLS goes bust, maybe SpaceX can purchase the 8.4m tooling for scrap, including the barge to transport, and build a 52 M1D engined HLV using a LOX/LH2 US which could do about 95MT in the single stick configuration with a 10m faring or 380MT in the heavy configuration. Talking about BFRs!! Although managing 150+ number of engines maybe a little too much. 52 M1D’s is 7.28mlbf.How do you come up with 52 Merlin and how they would be configured?
I doubt that the FX, FXH, FXX, Merlin 2 make sense any more.Learning curves for mass production of Merlin 1D mean that SpaceX will reap huge engine cost and reliability gains over time. But on top of that given their goal of rocket powered re-entry and landing they need to have a relatively low thrust engine on the recovered stage, something not achievable with a throttled Merlin 2.Also with propellant cross feed they have growth capacity from 3 to 5, 7 or even 9 parallel stages by simply beefing up center stage structure. That gives LEO capacity of up to 150 tonnes (higher than FXX), while lower initial staging velocities for 5-9 stage variants makes recovery of at least some of those stages even easier.
If they sized the engine around 650-700klbf, then they could do two engines on the 3.6m Falcon and 16 engines on a hypothetical 10m BFR delivering over 10Mlbf of thrust in a single-core configuration. I see no reason to make the engine any bigger than that.
I think if there were a market worth pursuing SpaceX could do better than a 9-core Falcon 9.
Quote from: ArbitraryConstant on 11/18/2011 08:09 pmI think if there were a market worth pursuing SpaceX could do better than a 9-core Falcon 9.But when the "market" is something like 1 flight every 2 years ......
Quote from: Hauerg on 11/19/2011 05:54 amQuote from: ArbitraryConstant on 11/18/2011 08:09 pmI think if there were a market worth pursuing SpaceX could do better than a 9-core Falcon 9.But when the "market" is something like 1 flight every 2 years ......It may not be worth servicing at all.
fun picture
Quote from: Tcommon on 01/04/2012 07:24 pmfun pictureMaybe that's what the huge underground test stand is really for.
Do you have any link(s) to the underground test stand for us?
Quote from: RocketmanUS on 01/04/2012 07:50 pmDo you have any link(s) to the underground test stand for us?http://www.wacotrib.com/wacotoday/135938808.htmlA little snippet from this article:"To fire all 27 engines at the same time, which is required to lift the massive rocket, a test stand will be built deep into the earth.“We are, in fact, looking at digging a very deep flame trench so that instead of firing Falcon Heavy engines on elevated test stands, they fire into the ground, reducing noise levels,” said Kirstin Brost Grantham, SpaceX spokeswoman.The new test stand will be connected to the tallest water tower in America. The tower will be 280 feet high and hold 500,000 gallons of water that can be emptied in less than 90 seconds via 6-foot-wide tubes. Rocket engine tests require water to buffer sound; a test of this magnitude will require a lot of water to minimize the noise."500000 divided by 90 seconds. That's 5555 gallons per second. Does that sound excessive for 27 merlin 1D's?
The Texas test stand is rated for 15MN. Almost for two Merlin 2, if those are ever to be developed. So if they actually wanted to design such an engine, they already have the test stand for it.
500000 divided by 90 seconds. That's 5555 gallons per second. Does that sound excessive for 27 merlin 1D's? Is there a rule of thumb for gallons per second per unit thrust?
Quote from: mrhuggy on 01/04/2012 09:26 pmQuote from: go4mars on 01/04/2012 08:28 pm500000 divided by 90 seconds. That's 5555 gallons per second. Does that sound excessive for 27 merlin 1D's? Sounds like they are building in extra capacity at the new stand for bigger things like Merlin 2.Is there a rule of thumb for gallons per second per unit thrust?
Quote from: go4mars on 01/04/2012 08:28 pm500000 divided by 90 seconds. That's 5555 gallons per second. Does that sound excessive for 27 merlin 1D's? Sounds like they are building in extra capacity at the new stand for bigger things like Merlin 2.
500000 divided by 90 seconds. That's 5555 gallons per second. Does that sound excessive for 27 merlin 1D's?
Sounds like they are building in extra capacity at the new stand for bigger things like Merlin 2.
Quote from: mrhuggy on 01/04/2012 09:26 pmSounds like they are building in extra capacity at the new stand for bigger things like Merlin 2.Wouldn't this stand be required in order to test cross-feeding in FH?
if they're going to build a test stand capable of firing Falcon Heavy at once, I see no reason they wouldn't test cross-feeding on the stand.
Quote from: Robotbeat on 01/05/2012 03:18 pmif they're going to build a test stand capable of firing Falcon Heavy at once, I see no reason they wouldn't test cross-feeding on the stand.Agreed. Most likely. Unless timeframe is a big factor: For example, some customer might need a cross-feeding FH demo by a certain date that is sooner than the test stand completion date. I have no idea if that's the case though.
Maybe that's what the huge underground test stand is really for.
Quote from: go4mars on 01/05/2012 01:14 pmQuote from: mrhuggy on 01/04/2012 09:26 pmQuote from: go4mars on 01/04/2012 08:28 pm500000 divided by 90 seconds. That's 5555 gallons per second. Does that sound excessive for 27 merlin 1D's? Sounds like they are building in extra capacity at the new stand for bigger things like Merlin 2.Is there a rule of thumb for gallons per second per unit thrust? no, you are not going to find indirect proof that Merlin 2 is being developed
The Texas test stand is rated for 15MN... So if they actually wanted to design such an engine, they already have the test stand for it.
Is there a rule of thumb for gallons per second per unit thrust?
Can somebody calculate the LEO lift capacity of a hypothetical Falcon XX Heavy (three 10m cores with cross feeding - with 6? Merlin2 engines each) with Merlin2 and/or Raptor upper stages?Are there any fundamental technical issues preventing such configuration?
If you copy the FH equation (3.3 times the 16tonnes of the F9b2), you'd get somewhere around 500tonnes.
to get 50 tonne chunks to Mars' surface (a stated goal)
Quote from: bulkmail on 02/08/2012 05:38 pmCan somebody calculate the LEO lift capacity of a hypothetical Falcon XX Heavy (three 10m cores with cross feeding - with 6? Merlin2 engines each) with Merlin2 and/or Raptor upper stages?Are there any fundamental technical issues preventing such configuration?If you copy the FH equation (3.3 times the 16tonnes of the F9b2), you'd get somewhere around 500tonnes.I guess that you should start thinking differently. You should start with a desired mission, then decide a vehicle that can do the mission in one or two launches.Let's say that you make it a two launches mission, where first you send the return vehicle and some exploration vehicle plus a surface habitat. On the second launch you send the crew with a space habitat, the Mars descent vehicle and the Earth return capsule.You've got to calculate some mass at Trans Mars Insertion orbit. That's what you should optimize then. LEO is not a good benchmark if you're going with straight launches, since low energy and high energy orbits require very different optimizations.
OK, so the mission I'm thinking about is Moon outpost/base and Moon cargo delivery on a big scale.
Anyway, with your 500 tonne rocket, that drops by some percent for reuse (40% for single stick apparently). Say a cross-fed version only drops by 20%. Would a 400 tonne to LEO rocket be likely to get 50 tonnes to the surface of Mars?
81 engines on a first stage is ido itic.
Difficult to find maybe so you can be forgiven.Edit : thanks Chris.This is the nine core Falcon Heavy thread - posting that so I can find it later.I find Jim's post reply #51 quite relevant
Hi. I have this (quite possibly hare-brained) idea that I would like to see discussed.As you all know SpaceX is planning the Falcon Heavy rocket, which is basically three Falcon 9 first stages strapped together with a stage on top. What is special is that it is going to use propellant cross feed, using up the propellant from the side stages first and then dropping them when empty. Thus they become better than the "half stage" strap on boosters that many rockets use in that they leave what is basically a full falcon 9 which is all ready moving fast. And they have an advantage over a full stage in that the engines of the center stage have been working the whole time rather than being dead weight.Now this seems to suggest an obvious further step, if we ever needed a super heavy lift rocket. What if you strapped nine cores together basically three falcon heavy first stages side by side, then cross fed from the two outer rows with a total of six cores first, followed by regular falcon heavy cross feed.Would it even need a top stage to achieve orbit then? How much could it lift? Since it is in a way just a repeated application of the original falcon heavy technology could it be done with *relatively* limited extra development cost (still expensive, everything in this field is). Now I know we don't need it for the foreseeable future. I know SpaceX are not planning to do it. It is still interesting to discuss the possibility though.
Just for historical interest, we proposed something similar for the NASA MSFC HLV study effort in mid-2010.
Quote from: HMXHMX on 02/13/2013 04:33 pmJust for historical interest, we proposed something similar for the NASA MSFC HLV study effort in mid-2010.Unstaged = the whole cluster is SSTO vehicle? Impressive final acceleration or deep throttling?Staged = green cores drop early? Cross feed?
What I was really trying to show is that common modules, built with high performance engines and lightweight tanks, can be clustered economically to provide heavy lift, thus obviating the need for a specialized HLV like NASA wanted. I knew in advance that it wouldn't be accepted but was making a point.
Just for historical interest, we proposed something similar for the NASA MSFC HLV study effort in mid-2010. SpaceX won one of the contracts (t/Space didn't) but I never saw any reports on any work performed; the study seems to have disappeared into the mists. Our architecture was based around clustering standard modules as described in the second graphic below.In the first graphic below, the "Class Three" engine is an RD-170 equivalent, or about 1.8Mlbf. So the module it is attached to is slightly larger than a F9v1.1, more along the lines of a Zenit first stage. But the enabling assumption we made was that you could build stages/modules with the Delta propellant Mass faction (PMF) on the oder of 0.95. F9v1.1 should be close to that if not better.
A SpaceX version of the Sat INT-21, however all RP-1/LOX.1st stage to use 9 Merlin 2's thrust rated for two engine out.2nd stage to use multiple Marlin 1D vacuum engines.Use shuttle VAB and launch pad.Three developments are the Merlin 2's, the ~10m cores, and large fairing.
Quote from: RocketmanUS on 03/25/2013 06:55 pmA SpaceX version of the Sat INT-21, however all RP-1/LOX.1st stage to use 9 Merlin 2's thrust rated for two engine out.2nd stage to use multiple Marlin 1D vacuum engines.Use shuttle VAB and launch pad.Three developments are the Merlin 2's, the ~10m cores, and large fairing.What is Sat INT-21?
Basically just the first two stages of the Saturn V. It would have need to have the instrument unit moved from the top of the third stage to the top of the third. Almost the same as the one that put the SpaceLab on orbit.
Just for historical interest, we proposed something similar for the NASA MSFC HLV study effort in mid-2010. SpaceX won one of the contracts (t/Space didn't) but I never saw any reports on any work performed; the study seems to have disappeared into the mists. Our architecture was based around clustering standard modules as described in the second graphic below.