LIVE: SpaceX Falcon 9 (Flight 2) - COTS-1 - Launch Updates - December 8, 2010

[Namechange User]

Well it strikes me that Spacex must be doing something right. They launched after quick fix (successfully) , separated the dragon (successfully), orbited (successfully) , reentered (successfully) and splashed down (successfully).

Not a bad day for people that criticize them for having limited or poor processes.

I don't believe anyone said they are not "doing something right", certainly no one credible.  Clearly they are doing very well and the evidence with respect to that speaks for itself.

That said, there were a few minor problems.  Those can generally be lumped into the term "process".  They obviously overcame them or had no real impact.  That's a good thing.  There is a learning curve with any new system and people who understand this business understand that very real fact.  But, people should not confuse speaking about these minor issues as being negative. 

[Cog_in_the_machine]

I thought we were a "world community" nowdays, and that a person's "national origin" didn't matter anymore...

Agreed, as I said my quibble is that he's more than a patriot. Not just focused on one country, but thinking how to benefit humanity in general.

[Kabloona]

Now, if they have a ballistic parachute as a backup, some of the fault tolerance might be relaxed a bit (at least that's how you would deal with a total system failure), but you'd still want the parachutes to be something you never end up needing to use...

I really think this is completely doable.  Remember, at Masten (and AA, and TGV, and all the other VTVL groups like RVT, DC-X, etc) the goal was to land every single time on rocket propulsion.  It could just be that every single one of these groups is crazy, but remember--parachutes aren't 100% infallible either.  You want the solution to be a lot better than the alternatives, but parachutes set a pretty low bar for competition, reliability-wise.

~Jon

Jon, as Lee Jay pointed out, parachutes "kick butt ISP-wise." Why not take a hybrid approach that uses the chutes and also a smaller propulsion system to do terminal course correction and final retro firing for the soft, precision "pad" landing that Elon is talking about?

As for reliability, Elon has said they needed only one chute out of three. Seems like pretty good odds to me.

[go4mars]

No, it is what I said it was.

http://cosmiclog.msnbc.msn.com/_news/2010/12/06/5600599-spacex-gets-set-for-next-giant-leap

Musk said his $2.5 billion figure for a super-heavy-lift rocket was based in part on the concept that 80 percent of the money Congress is expected to devote to heavy-lift development would go toward the standard cost-plus method for funding spacecraft development, with 20 percent going to the kind of fixed-price, milestone-based approach that is being used for the NASA program that's funding SpaceX's effort. "I find myself in this bizarre position where people are saying, 'You couldn't possibly do it for such a low amount as $2.5 billion,'" he said. "And actually, I have trouble trying to figure out how we'd spend so much money. In order to get to $2.5 billion, I'd have to assume that a whole bunch of things go horribly wrong during the development process."

Then what does the $2.5 billion figure represent? 

[marsavian]

No, it is what I said it was.

http://cosmiclog.msnbc.msn.com/_news/2010/12/06/5600599-spacex-gets-set-for-next-giant-leap

Musk said his $2.5 billion figure for a super-heavy-lift rocket was based in part on the concept that 80 percent of the money Congress is expected to devote to heavy-lift development would go toward the standard cost-plus method for funding spacecraft development, with 20 percent going to the kind of fixed-price, milestone-based approach that is being used for the NASA program that's funding SpaceX's effort. "I find myself in this bizarre position where people are saying, 'You couldn't possibly do it for such a low amount as $2.5 billion,'" he said. "And actually, I have trouble trying to figure out how we'd spend so much money. In order to get to $2.5 billion, I'd have to assume that a whole bunch of things go horribly wrong during the development process."

Then what does the $2.5 billion figure represent? 

COTS like milestone payments along the way developing/integrating the rocket but he expects to be paid like any other contractor would for building the new lower/upper engine/stages. He maybe cheaper than everyone else but not a magnitude of order cheaper .

[Crispy]

Jon, as Lee Jay pointed out, parachutes "kick butt ISP-wise." Why not take a hybrid approach that uses the chutes and also a smaller propulsion system to do terminal course correction and final retro firing for the soft, precision "pad" landing that Elon is talking about?

As for reliability, Elon has said they needed only one chute out of three. Seems like pretty good odds to me.

My interpretation is that the powered landing will be performed by the same engines that would otherwise be used by the 'pusher' LAS. Can we get some figures for the total impulse required for a powered landing vs. abort? My intuition says the requirements would be about the same, thrust and fuel-wise.

[jabe]

That's all pretty awesome, but are the gripper arms meant to fall off a toasted strongback?

watching the video of the launch you can see the arm fall off.
Here is one highlight video that shows it happening..
at 0:37  mark..and ~6:20 mark
jb

[Namechange User]

Jon, as Lee Jay pointed out, parachutes "kick butt ISP-wise." Why not take a hybrid approach that uses the chutes and also a smaller propulsion system to do terminal course correction and final retro firing for the soft, precision "pad" landing that Elon is talking about?

As for reliability, Elon has said they needed only one chute out of three. Seems like pretty good odds to me.

My interpretation is that the powered landing will be performed by the same engines that would otherwise be used by the 'pusher' LAS. Can we get some figures for the total impulse required for a powered landing vs. abort? My intuition says the requirements would be about the same, thrust and fuel-wise.

I would hazard a guess those details are not really know outside SpaceX at this point.  However, the impulse would likely be a function of the landing profile, if the engines are throttable and concept of operations. 

If it is to be LAS-based, you'd likely need parachutes still since if your LAS was activated during launch you would end up landing in the water.  So a hybrid LAS/parachute landing may be what they are thinking about here.  Time will tell I suppose. 

[Cog_in_the_machine]

Good catch jabe.

[martin hegedus]

I agree it was a design flaw and I take the point about it being a process failure, but I think the argument there is very weak.  Yes they had a design flaw that became apparent on the first flight where the turbopump drain plume expanded in vacuum to impinge on and freeze the roll control system, where it does not at sea level.  And for the record I do not consider this anomaly a process failure either because of SpaceX's conscious decision to flight test the second stage rather than paying to test in an altitude test facility (i.e. their process).  The obvious recovery from that anomaly should have been to scrub the design for any other altitude effects, especially as relates to plume expansion and impingement.   

I haven't dug into why the roll control failed so I don't know the ins and outs of it.  But, in the missile design community, best practices in regards to plumes, and their interactions, is well known.  The expert knowledge is out there both in the government and civilian R&D communities.  And one doesn't necessarily need to go to an altitude test facility since engineering methods and higher fidelity methods, such as CFD, are available to assess areas of possible risk.  If SpaceX violated a rule of thumb in regards to plumes and plume interactions, this is a design process failure.

[Robotbeat]

No, it is what I said it was.

http://cosmiclog.msnbc.msn.com/_news/2010/12/06/5600599-spacex-gets-set-for-next-giant-leap

Musk said his $2.5 billion figure for a super-heavy-lift rocket was based in part on the concept that 80 percent of the money Congress is expected to devote to heavy-lift development would go toward the standard cost-plus method for funding spacecraft development, with 20 percent going to the kind of fixed-price, milestone-based approach that is being used for the NASA program that's funding SpaceX's effort. "I find myself in this bizarre position where people are saying, 'You couldn't possibly do it for such a low amount as $2.5 billion,'" he said. "And actually, I have trouble trying to figure out how we'd spend so much money. In order to get to $2.5 billion, I'd have to assume that a whole bunch of things go horribly wrong during the development process."

Then what does the $2.5 billion figure represent? 

COTS like milestone payments along the way developing/integrating the rocket but he expects to be paid like any other contractor would for building the new lower/upper engine/stages. He maybe cheaper than everyone else but not a magnitude of order cheaper .

That's not what he said. He said he can do it for $2.5 billion. Could he be any clearer?

(Doesn't mean he actually CAN do it for that. That remains to be seen.)

[llo2015]

Jon, as Lee Jay pointed out, parachutes "kick butt ISP-wise." Why not take a hybrid approach that uses the chutes and also a smaller propulsion system to do terminal course correction and final retro firing for the soft, precision "pad" landing that Elon is talking about?

As for reliability, Elon has said they needed only one chute out of three. Seems like pretty good odds to me.

My interpretation is that the powered landing will be performed by the same engines that would otherwise be used by the 'pusher' LAS. Can we get some figures for the total impulse required for a powered landing vs. abort? My intuition says the requirements would be about the same, thrust and fuel-wise.

The LAS burn will require a Delta-V of 400-500 m/sec with a total burn time of less that five seconds.  For precision landing, the landing engine may have the same Delta-V (more or less) but the burn will 30 seconds or more.  In my example, the ratio of thrust difference is proportional to burn time (more or less).

[marsavian]

No, it is what I said it was.

http://cosmiclog.msnbc.msn.com/_news/2010/12/06/5600599-spacex-gets-set-for-next-giant-leap

Musk said his $2.5 billion figure for a super-heavy-lift rocket was based in part on the concept that 80 percent of the money Congress is expected to devote to heavy-lift development would go toward the standard cost-plus method for funding spacecraft development, with 20 percent going to the kind of fixed-price, milestone-based approach that is being used for the NASA program that's funding SpaceX's effort. "I find myself in this bizarre position where people are saying, 'You couldn't possibly do it for such a low amount as $2.5 billion,'" he said. "And actually, I have trouble trying to figure out how we'd spend so much money. In order to get to $2.5 billion, I'd have to assume that a whole bunch of things go horribly wrong during the development process."

Then what does the $2.5 billion figure represent? 

COTS like milestone payments along the way developing/integrating the rocket but he expects to be paid like any other contractor would for building the new lower/upper engine/stages. He maybe cheaper than everyone else but not a magnitude of order cheaper .

That's not what he said. He said he can do it for $2.5 billion. Could he be any clearer?

(Doesn't mean he actually CAN do it for that. That remains to be seen.)

Congress is paying 5 times for the HLV development than his arbitrary 20% COTS-like top up, could that be any clearer ? The whole statement is just some WAG he made up, who says the upper/lower stages would only be $10bn anyway and what about the new pad too.

80 percent of the money Congress is expected to devote to heavy-lift development would go toward the standard cost-plus method for funding spacecraft development, with 20 percent going to the kind of fixed-price, milestone-based approach that is being used for the NASA program that's funding SpaceX's effort.

[Robotbeat]

He's talking about keeping the (SDLV, presumably) SLS, but using some of the money for a Falcon-series HLV.

[jongoff]

You want the solution to be a lot better than the alternatives, but parachutes set a pretty low bar for competition, reliability-wise.

~Jon

Yeah...but they kick butt ISP-wise.

Well, what ultimately matters is the overall weight, and from what I've seen parachute landing and VTVL systems tend to trade not too differently from each other.  Depending on engine characteristics, the delta-V you need for landing is pretty small, typically less than 150-200m/s IIRC.  For any reasonable propellant combo other than monopropellants, that doesn't require that much propellant.  Worst case 200m/s deceleration with a 200s Isp rocket engine gives about 10% of mass at engine ignition in propellant--which comes out pretty close to what parachutes weigh...

Now you'd still want a ballistic parachute as backup, but overall you wouldn't come out much heavier than a parachute-based system, and you get a whole lot more control, precision, gentler touchdown, easier reuse, etc.

I'm hoping that 50 years from now, parachute landings and splashdowns are seen as an embarrassing anachronism...

~Jon

[jongoff]

Is that still true if your propulsive Landing Thrusters also double as your LAS?

I do not understand. How are you going to land after an abort if you expended the landing fuel to perform the abort?

You've got me there..  As I chuckle..  With the Parachute?

Although at Launch you'd still have all the Maneuvering and OMS propellant you could use.. Far more than you have at landing.  Is that enough for a high thrust "low ISP" burn for separation, and to still land?  I don't know.

One thing to remember with liquid propellants is that it's possible to have one set of tanks feeding several different engine sorts...

Your total propellant loads becomes the greatest of the two scenarios:

1) emergency mission with LAS abort and propulsive landing dV requirements

2) nominal mission with OMS, RCS, deorbit, and landing dV requirements

~Jon

[jongoff]

  Mr. Musk stated that he doesn't quite know where he would spend $2.5B.  I fear that he'll find out just where it all goes, and the profit margin, and public value, will get eaten away.

He doesn't have a HLV lower stage or engine, HLV upper stage or engine, HLV pad or facilities. That figure he is quoting is just hot air without specific context on what part of the HLV he is referring to and is definitely not apples to apples compared to say SLS as he can't build a 125mT HLV from where he is now with only $2.5bn.
...

I think he very well thinks he can build a 125 mT HLV from where he is right now with only $2.5 billion. That's his point.

He may or may not be able to do that, but that's what he claims.

And he'd have to be off by a very large margin (much larger than any of the other cost/time errors SpaceX has made in the past) to come anywhere near as expensive as many of the alternatives.

~Jon

[marsavian]

He's talking about keeping the (SDLV, presumably) SLS, but using some of the money for a Falcon-series HLV.

No, he's talking about the upper and lower stages of the HLV, not the SLS ...

http://web02.aviationweek.com/aw/mstory.do?id=news/awst/2010/11/29/AW_11_29_2010_p28-271784.xml&channel=space&headline=NASA%20Studies%20Scaled-Up%20Falcon,%20Merlin

Based on a roughly evenly split $10 billion budget for heavy lift, with half for the boost stage and half for the upper stage, “we’re confident we could get a fully operational vehicle to the pad for $2.5 billion

[llo2015]

Is that still true if your propulsive Landing Thrusters also double as your LAS?

I do not understand. How are you going to land after an abort if you expended the landing fuel to perform the abort?

You've got me there..  As I chuckle..  With the Parachute?

Although at Launch you'd still have all the Maneuvering and OMS propellant you could use.. Far more than you have at landing.  Is that enough for a high thrust "low ISP" burn for separation, and to still land?  I don't know.

One thing to remember with liquid propellants is that it's possible to have one set of tanks feeding several different engine sorts...

Your total propellant loads becomes the greatest of the two scenarios:

1) emergency mission with LAS abort and propulsive landing dV requirements

2) nominal mission with OMS, RCS, deorbit, and landing dV requirements

~Jon

If there is a second stage engine out event late in powered flight, the Delta-V and propellant requirements associated with an abort-to-orbit or an abort-to-targeted landing zone will probably be greater than LAS or a powered landing.

[MP99]

He's talking about keeping the (SDLV, presumably) SLS, but using some of the money for a Falcon-series HLV.

No, he's talking about the upper and lower stages of the HLV, not the SLS ...

http://web02.aviationweek.com/aw/mstory.do?id=news/awst/2010/11/29/AW_11_29_2010_p28-271784.xml&channel=space&headline=NASA%20Studies%20Scaled-Up%20Falcon,%20Merlin

Based on a roughly evenly split $10 billion budget for heavy lift, with half for the boost stage and half for the upper stage, “we’re confident we could get a fully operational vehicle to the pad for $2.5 billion

SpaceX believes this arrangement could allow the use of an unchanged Falcon 9 upper stage. “That way you get a three-stage super-heavy-lift vehicle, and all you’ve done is scale up the Merlin and Falcon 9 first stage. You essentially get a second stage for free,” says Musk.

One sentence says $5B for upper stage, the other says upper stage is free because re-use the F9 one. Implies $10B doesn't refer to the 'X'.

So, does the "roughly even split" refer to SLS? IE: "assuming SLS core would be $5B, we could do ours for $2.5B, and re-use the Falcon upper stage for free"?

But F9 u/s would also limit this to LEO only, even with the Raptor upper stage.

cheers, Martin