LIVE: SpaceX - Falcon I (Mk.II) NET March 20 (Attempt 2)

[JonSBerndt]

rkoenn - 23/3/2007  7:03 AM
While I respect SpaceX's accomplishment for being the most "private" company to accomplish this feat, they, in my opinion, still have a ways to go, I don't think I would call it 90% success.  ...   It is great he did get a good first stage performance and is on the way, but until he actually reaches the desired orbit the job is not done, 90% (or whatever) simply does not qualify as a success, you have to reach orbit to do the mission.

Every new aircraft goes through a series of testing steps prior to making its first flight. That includes taxi tests, maximum braking tests, etc.  With a rocket, how do you test the second stage in realistic conditions? IMHO, the question to ask is not, "Did they make orbit?", but, "Did they make their test objectives?". Given what SpaceX has come to be over the years, and the facilities, processes, and accomplishments they have built up, I think it's hard to argue against their assessment of where they are. They may only be a software tweak away from orbit. The question I have in my mind is, can they maintain the quality of their work once they achieve orbit, and build up a track record like Atlas, for instance?

Jon

[meiza]

I agree with Jon except with a caveat: spacex (like many other companies) seemed to redefine their goals and cheer the first flight as some success when it was a clear failure. Perhaps if they had gotten to stage separation... People grew fed up with this.

If they would clearly say: "this is just a test, we aim for this and this and if it reaches orbit, we're happy, but we don't expect it to be very probable." I'd be happy.
Instead we get pr speak about how this will be a great satellite launch and cheers and automatic success declaring after what ever happens, it gets tiring pretty quick.

[aero313]

Jim - 23/3/2007  8:41 AM

Spacex's mentality is "we want to fly rockets"  when it is really " we are going to launch spacecraft"  Their planner's guide and some other documentation reflect this.

SpaceX is not alone in this area.  Virtually every startup launch vehicle development effort I've been involved with sees the rocket as the end item and not just a delivery vehicle for the payload.  Even worse, mosts of these companies are propulsion-centric, not even launch vehicle system-centric.  At the risk of sounding like a broken record, the launch vehicle is the delivery van.  Do you really care what kind of truck UPS uses to deliver you package?  Of course not.  All you care about is that the package arrives on time and is not damaged in the process.  Musk wants to drive the cost of space access down, and that's admirable.   The problem is that what matters is still that the payload can complete it's mission.  Period.  Cheap launch is meaningless if the payload can't complete the mission.

[rkoenn]

I  agree with aero.  No matter what level of "success" the mission reaches if the satellite does not reach the intended orbit it is not a success.  I truly respect what SpaceX has accomplished but if they do not reach orbit with a paying satellite next time they have failed their mission.  A comm satellite at 500 miles up is a failed mission.  It will be difficult to go from this partial success and be fairly certain of a successful mission next time.  Until you have proven your vehicle with a completely successful launch to the correct orbit you have not completed the mission.  It took many of the early vehicles a number of flights to claim success.  However the customer was not satisfied until that happened.  I personally would not bank my satellite on the next flight of Falcon as believing I had a good chance of success.  I think he needs a completely successful test before I would be willing to pay for a launch.  Hopefully the data they do have will be sufficient to pinpoint the problem.  That at least in my mind would enhance their chances next time.  However if they have to go on hunches a success next time is less likely.

[Jim]

As said before, designing and flying a rocket is "easy".  The hard part is to do it over and over again.  In one of my previous lives, I had a similar experience.  It was fun working all hours of the day and weekends to for the first two launches.   When it became a routine and a long term program, the hard part was maintaining focus and documenting what we had done and  training others to do to same work.  Other people had to be trained since it would be impossible for the "original" crew to maintain the work pace.  People wanted to take vacations and enjoy life events for some reason.  Also at this time, some peope want to move on.  This where costs increase, more people are needed to cover the work, documenting the processes used

[Danderman]

Eeyore3061 - 20/3/2007  7:46 PM  

Danderman - 20/3/2007  10:39 PM  

I was not aware that pressure fed engines require ullage motors.

 Yes, to keep them from swallowing a bubble of pressurant.    ... and possably locking up the lines      Michael.

Let me try this again, I was not aware that the Falcon 1 upper stage had ullage motors.

 

[Jim]

Danderman - 23/3/2007  11:33 AM

Eeyore3061 - 20/3/2007  7:46 PM  

Danderman - 20/3/2007  10:39 PM  

I was not aware that pressure fed engines require ullage motors.

 Yes, to keep them from swallowing a bubble of pressurant.    ... and possably locking up the lines      Michael.

Let me try this again, I was not aware that the Falcon 1 upper stage had ullage motors.

It doesn't have them

[jimvela]

Jim -
The hard part is to do it over and over again. [snip]

Oh, man- Jim has this so right on the money!

[Jim]

jimvela - 23/3/2007  11:53 AM

Jim -
The hard part is to do it over and over again. [snip]

Oh, man- Jim has this so right on the money!

It gets stressful when you have a long streak of success.  You know that the numbers game is going to get you, so you become more diligent , which increases the stress.  

Along these same lines, there is other stress makes make related launches not so fun anymore.  I left a shuttle related program in 2001 because it was due.

Also something related.  The program I was involve with had a 100% success on the first mission.  It concerned the management bacaus they didn't want us to get cocky and slip up on the second one

[MySDCUserID]

MKremer - 22/3/2007  11:49 PM

I think if SpaceX's next lauch is a success (a 'complete' success in that the booster and 2nd stage put the payload into the required orbit), there's going to be some marketing/pricing scrambling and PR propaganda against what SpaceX is able to do.

I really think Falcon9 is going to be the real test of whether SpaceX can do what they've claimed - if it works well they'll be a big shakeup in the launch market; if they are still having probems look for lots and lots of competing PR against what they're attempting to do.

A lot of the expense of the larger launch systems is related to the requirements placed on the contractor by the government customer.  This often results in a lot of work and employees that are not directly tied to engineering and actually building/maintaining hardware.  How would such requirements impact their cost model?  Also, I am very curious of just how compliant with AS9100 they are, and how they plan on sustain that AS9100 certification.  Of course, such processes are normally proprietary in nature.

[jimvela]

kevin-rf - 23/3/2007  6:48 AM

http://www.spacedaily.com/reports/SpaceX_Confirms_Stage_Bump_On_Demoflight_2_999.html

SpaceX seems to be communicating with them...

  1. SpaceX is admitting the stages bumped, but pointing to the fact that the nozzle didn't shatter is proof of the robustness of the design.
  2. They failed to recover the first stage. They are blaming a combo of a non working GPS (I thought they had two on this sucker) and range rules that require the recovery ship be outside of the fall zone.
  3. Full speed ahead to the next launch.

1)  The stages bumping is a problem.  Robustness in the engine is nice, but is not an indication of overall success.   Is the  bump a reason that the chutes failed and resulted in no recovery of the 1st stage, which would have been an engineering analysis gold mine for them?  System failures are never a success, even if they contribute to validation of the apparent robustness of a different system.

2)  They don't know if the chutes opened.  Where is the telemetry?  They flew with a non-functioning GPS (half of the system).  They didn't know where the stage ended up, and couldn't locate it via sonar or visual means.  Probably because the chutes didn't open and there wasn't anything to recover.  Maybe because they just flat lost it in the sea, in part because they don't have a good way to get the recovery vessel on site in a timely manner. This doesn't sound to me like a working 1st stage recovery system.  Further, they clearly don't have a good process for getting the recovery team and facilities into place, nor a good feel for what the actual minimum required hardware set is. I cannot see how it can be spun as a success for this system, either.

They state that recovery isn't needed for the current pricing scheme, which doesn't make sense.  If they don't need the recovery system at this price point, then DELETE the recovery system and increase vehicle performance margins and increase space in the interstage area for clearance so they don't keep smacking the engine bell.  If they do want it to end up recoverable/rebuildable, then they'll need far better performance of this aspect of the system.

3)  More lessons are ahead.  I still hope they can address everything that went wrong this time.  We'll see what we see.  I suspect DARPA wants a post-flight analysis on this one as well, even if they do let them proceed 'full speed ahead' for the next launch.

Getting to where they consistently get everything right is still the big challenge for them, IMHO.  Failure to produce a system failure in a single test does not constitute proof that a system is workable long term, it only proves that the system can occasionally work.

[Danderman]

So, how long does everyone think it will take for the next launch?

Four months, ie early August or so?

Six months?  October?

Next year? Minimum of nine months?

[Danderman]

A stupid question for the crowd: didn't the second stage on the very first Falcon I suffer a structural failure? If so, doesn't this imply that Elon has at least one extra first stage lying around?

[Jim]

MySDCUserID - 23/3/2007  12:26 PM

MKremer - 22/3/2007  11:49 PM

I think if SpaceX's next lauch is a success (a 'complete' success in that the booster and 2nd stage put the payload into the required orbit), there's going to be some marketing/pricing scrambling and PR propaganda against what SpaceX is able to do.

I really think Falcon9 is going to be the real test of whether SpaceX can do what they've claimed - if it works well they'll be a big shakeup in the launch market; if they are still having probems look for lots and lots of competing PR against what they're attempting to do.

A lot of the expense of the larger launch systems is related to the requirements placed on the contractor by the government customer.  This often results in a lot of work and employees that are not directly tied to engineering and actually building/maintaining hardware.  How would such requirements impact their cost model?  Also, I am very curious of just how compliant with AS9100 they are, and how they plan on sustain that AS9100 certification.  Of course, such processes are normally proprietary in nature.

They are going to have to meet all the gov't requirements if they are going to get a gov't.  Most of the work required IS engineering and engineering data.  If they got a 3rd party AS9100 certificate, it means they met ALL the requirements.  Can't get a NASA contract without being AS9100 compliant.

[JonSBerndt]

Jim - 23/3/2007  10:51 AM

Danderman - 23/3/2007  11:33 AM

Eeyore3061 - 20/3/2007  7:46 PM  

Danderman - 20/3/2007  10:39 PM  

I was not aware that pressure fed engines require ullage motors.

 Yes, to keep them from swallowing a bubble of pressurant.    ... and possably locking up the lines      Michael.

Let me try this again, I was not aware that the Falcon 1 upper stage had ullage motors.

It doesn't have them

It does have them, in a fashion (see: http://www.spacex.com/falcon1.php#second_stage):

"Helium pressurization is again provided by composite over wrapped inconel tanks from Arde. However, in this case the helium is also used in cold gas thrusters for attitude control and propellant settling when a restart is needed."

It's not clear by the wording above if second stage ignition (the first time) uses the thrusters for propellant settling. This is the part where I am not clear on whether or not they are needed for the initial ignition.

The point remains: was there a pitch or yaw acceleration at sep, and if so, what caused it?

Jon

[yinzer]

Jim - 23/3/2007  8:04 AM

As said before, designing and flying a rocket is "easy".  The hard part is to do it over and over again.  In one of my previous lives, I had a similar experience.  It was fun working all hours of the day and weekends to for the first two launches.   When it became a routine and a long term program, the hard part was maintaining focus and documenting what we had done and  training others to do to same work.  Other people had to be trained since it would be impossible for the "original" crew to maintain the work pace.  People wanted to take vacations and enjoy life events for some reason.  Also at this time, some peope want to move on.  This where costs increase, more people are needed to cover the work, documenting the processes used

This is not unique to the rocketry field.  It's a fact of life in the tech industry as well.  At least over here the early people usually have some stock options that vest over a few years to encourage them to stick around.

[JonSBerndt]

JonSBerndt - 23/3/2007  12:23 PM
It does have them, in a fashion (see: http://www.spacex.com/falcon1.php#second_stage):

"Helium pressurization is again provided by composite over wrapped inconel tanks from Arde. However, in this case the helium is also used in cold gas thrusters for attitude control and propellant settling when a restart is needed."

It's not clear by the wording above if second stage ignition (the first time) uses the thrusters for propellant settling. This is the part where I am not clear on whether or not they are needed for the initial ignition.

I see by another of Jim's posts that springs are used for separation in some cases, which also serves to settle propellant - so perhaps this is why the thrusters would be used to settle propellant after sep has occured (and a restart is attempted). Those must be some strong springs!

Jon

[Jim]

JonSBerndt - 23/3/2007  1:23 PM

Jim - 23/3/2007  10:51 AM

Danderman - 23/3/2007  11:33 AM

Eeyore3061 - 20/3/2007  7:46 PM  

Danderman - 20/3/2007  10:39 PM  

I was not aware that pressure fed engines require ullage motors.

 Yes, to keep them from swallowing a bubble of pressurant.    ... and possably locking up the lines      Michael.

Let me try this again, I was not aware that the Falcon 1 upper stage had ullage motors.

It doesn't have them

It does have them, in a fashion (see: http://www.spacex.com/falcon1.php#second_stage):

"Helium pressurization is again provided by composite over wrapped inconel tanks from Arde. However, in this case the helium is also used in cold gas thrusters for attitude control and propellant settling when a restart is needed."

It's not clear by the wording above if second stage ignition (the first time) uses the thrusters for propellant settling. This is the part where I am not clear on whether or not they are needed for the initial ignition.

The point remains: was there a pitch or yaw acceleration at sep, and if so, what caused it?

Jon

They don't have ullage MOTORS, i.e. not solids.   All upperstages have aft facing thrusters for ullage control for restarts.  But these and most RCS systems are not used during staging since the other forces present (aero, ordnance, spring, etc) are much larger and overwhelm them.  LV's rely on the upperstage engine TVC to correct the errors.  Much like what was seen on this launch

[JIS]

Jim - 23/3/2007  1:48 PM

faramund - 23/3/2007  8:31 AM
. Even if they could never solve the second stage problem. If it was possible to buy a functioning second stage from another company ,

No.  The second stage is the "core" of the launch vehicle.  

Before the first launch they had lot of structural, instrumentation and pad infrastructure problems. The second flight showed that most of them are successfuly solved. Some bugs with 2nd stage appeared last flight but I'm pretty much sure they won't appear next time.
However, I'm afraid that there are still some flaws which havn't been revieled yet.
With proper know-how, testing and procedures this could be avoided, but it looks like simply flying Falcon 1 is cheaper than testing. I hope that Falcon make it to the orbit before costumers loose their patience.
Loosing Falcon 9 would be bigger upset so I don't expect to see it flying before 2010.  

[George CA]

Local radio news in LA claiming the second stage suffered a structural collapse and is currently space debris.