FAILURE: SpaceX Falcon I Launch III - August 2

[Ronsmytheiii]

The design is fine, the implementation is bad

What in your opinion is the best way to fix the problem?  Would the mentioned ullage motors help/hinder the design?

[Dalon]

The Russians had some go bad on the Soyuz SM.
 I don't know where Spacex buys their pyro bolts but sice they are going for low cost they might have used a Russian supplier for them and got some from the same bad batch.

Somewhere on the SpaceX site it mentions that they use an industry standard explosive bolt that has never caused a mission failure.

I've never been happy with the concept of explosive bolts because they definitely are a single point of failure.  Still, one cannot argue with success, explosive bolts have historically functioned to an extreme level of reliability. 

One reason these bolts are so reliable is that they are typically dual firing.  Two independent charges per bolt, with each charge wired to a different firing circuit to provide a very high level of redundancy.

[aero313]

The design is fine, the implementation is bad

What in your opinion is the best way to fix the problem?  Would the mentioned ullage motors help/hinder the design?

The BEST way to fix the problem is to find out what the real problem is before speculating about a fix.

[Dalon]

From the SpaceX site.

Regarding F1 separation:

"Stage separation occurs via dual initiated separation bolts and a pneumatic pusher system. All components are space qualified and have flown before on other launch vehicles."
http://www.spacex.com/falcon1.php

Regarding the pyros on the F9

"Moreover, the stage separation bolts are all dual initiated, fully space qualified and have a zero failure track record in prior launch vehicles."

They seem to have removed this wording from the active page, but it is still in Google's cache:
http://64.233.169.104/search?q=cache:bkgUxkWGqbYJ:www.spacex.com/falcon9.php+site:spacex.com

[pm1823]

I don't know where Spacex buys their pyro bolts but sice they are going for low cost they might have used a Russian supplier for them and got some from the same bad batch.

LOL. His grenades are of wrong system . (с) White Sun of the Desert

[Rocket Girl]

When the first attempt was aborted , I was certain that the launch would be delayed (several days or weeks).  I was shocked to discover that a second attempt was made within minutes of the first abort.   I find it difficult to believe that a methodical examination was made.  The decision to launch a second time so soon was irresponsible.

Safety is paramount.   A delay to ensure nothing was damaged that could cause harm is crucial.  A delay to ensure that “all systems are go” is also crucial.   

My concern isn’t “why” the failure happened.  My concern is the actions of Space X last night. Had the launch been a success or a failure, an investigation would have proven that SpaceX is a responsible, reputable aerospace company. 

I want SpaceX to have great success,  I wish them the best in the future.

[rdale]

I find it difficult to believe that a methodical examination was made.  The decision to launch a second time so soon was irresponsible.

That's quite an accusation... What evidence do you have that a methodical examination was NOT made? How have you connected the first abort with the mission failure?

[Dalon]

When the first attempt was aborted , I was certain that the launch would be delayed (several days or weeks).  I was shocked to discover that a second attempt was made within minutes of the first abort.   I find it difficult to believe that a methodical examination was made.  The decision to launch a second time so soon was irresponsible.

Safety is paramount.   A delay to ensure nothing was damaged that could cause harm is crucial.  A delay to ensure that “all systems are go” is also crucial.   

My concern isn’t “why” the failure happened.  My concern is the actions of Space X last night. Had the launch been a success or a failure, an investigation would have proven that SpaceX is a responsible, reputable aerospace company. 

I want SpaceX to have great success,  I wish them the best in the future.

So your contention is that Any abort for any reason should require a complete stand down and re-evaluation of every single system component?

Do you get your car engine tuned up every time you have a flat tire?  The point being, a small anomaly doesn't always require a complete stand down. 

As things stand now, it is entirely possible that the reason for the initial abort may have had absolutely nothing to do with the mechanism of failure.   All I read of the first abort was that one of 180 criteria was <1% under nominal.

If I had to guess, I'd say it's unlikely that the mechanism of failure was in any way impacted by the initial abort.  I could be wrong, but that would be my guess.

[jimvela]

Do you get your car engine tuned up every time you have a flat tire?  The point being, a small anomaly doesn't always require a complete stand down. 

True, but if you get a flat tire you at least look over that wheel/tire.  If, for example, you find that the outside edge of the tire was all chewed up, you probably want to at least check for alignment or other problems.

Her point is that the first abort lit the engine briefly.  Lots of things can go wrong with a shutdown of a lit engine- including things that could be induced by the shock of engine start.

Being able to quick turn from an abort at engine start is impressive as all hell.  Needing to do so regularly is not.

As things stand now, it is entirely possible that the reason for the initial abort may have had absolutely nothing to do with the mechanism of failure.   All I read of the first abort was that one of 180 criteria was <1% under nominal.

Quite true.  Lets see what SpaceX reports as the root cause(s)

If I had to guess, I'd say it's unlikely that the mechanism of failure was in any way impacted by the initial abort.  I could be wrong, but that would be my guess.

Fair enough.  The 2nd launch flew to staging with a start/abort engine after a quick turn, then had a staging incident which caused slosh.  Possibly corrected in the 3rd LV.

The 3rd LV flew to staging with a start/abort engine after a quick turn, then had a staging incident which most of us have seen nothing of and don't know what happened.

Note that staging happens in both failures, but so does an engine lit abort followed by quick turnaround, followed by launch.  See two things that are common between both failures?

It will be interesting to see what SpaceX find.

[hop]

All I read of the first abort was that one of 180 criteria was <1% under nominal.

First of all, I agree that we have know way of knowing if this specific decision was justified or not. It certainly could have been.

However, it still raises some questions in my mind:
If the limit can be raised in a few minutes, how detailed was the analysis that went into setting it in the first place ?

This value being close to the limit should either have been within existing test experience, or outside it.

If it frequently came close to the limit in testing, then the analysis should have been done, and the limit raised before launch. Especially given the short time it took to conclude that raising it was safe. While it's great that F1 can start/abort, it's a pretty violent event, and seems like something you'd rather avoid.

If it normally stayed far away from the limit, then that would suggest that reaching it might have been out of character, and a stand-down would be warranted even if the value itself appears safe. When your hardware talks, you should listen.

OTOH, it's possible that the value was clearly related to some particular environmental condition at the launch, not commonly encountered in testing. E.g. difference in temperature between launch site and test stand.

[bigdog]

Anyone know how they execute the separation?  I mean does the second stage avionics do all the work or is there a box on the first stage that's commanded to fire the sep system by the computer on the second?

[Rocket Girl]

My crystal ball doesn’t work, never has, never will.  I never said that the first abort was the cause of the failure.  I don’t know what happened.  SpaceX will revue the data and discover the cause in due time.

SpaceX’s (falcon‘s) track record isn’t great.  A “complete stand down” would have been prudent under the circumstances. 

[AresWatcher]

SpaceX’s (falcon‘s) track record isn’t great.  A “complete stand down” would have been prudent under the circumstances. 

Incorrect.

The cause of the first abort was due to a turbopump being one percent out of spec, breaching their version of LCC. That is actually a very right LCC, and they may have lauched without issue.

The failure was to do with the separation of the first and second stages.

A standdown due to the first scrub is very unlikely to have made any difference on this same vehicle.

The decision to recycle was based on their own proceedure, and unless you are claiming to know the vehicle better than the engineers who designed such a proceedure....well

[rolfkap]

OTOH, it's possible that the value was clearly related to some particular environmental condition at the launch, not commonly encountered in testing. E.g. difference in temperature between launch site and test stand.

Well, they did a hot fire of the stage at the end of June, conditions should be pretty similar.  Shutting down for these things means one of these:

1) Hardware does not act the same every time.
2) Limits are set too tightly.
3) Instrumentation is not precise enough.

#1 would be bad, but I'm guessing it is more of a combination of 2 and 3.  I would have thought the abort on flight 2 would have lead to a review of go/no-go limits, but maybe not.  They obviously are convinced of the robustness of the Merlin.

--Rolf

[yinzer]

The cause of the first abort was due to a turbopump being one percent out of spec, breaching their version of LCC. That is actually a very right LCC, and they may have lauched without issue.

The one percent is irrelevant.  Setting redlines and aborting when you exceed them is standard practice.  Running close enough to the redlines that you regularly exceed them and have to abort is not standard practice.

SpaceX claimed that they were going to do things very differently than the rest of the rocket industry, and cut out a bunch of expensive stuff that wasn't needed but was only done out of conservatism and paranoia.  They have since gone zero-for-three.

Maybe standard rocket industry practice makes sense after all, or maybe SpaceX is doing something uniquely wrong (letting Elon Musk make technical decisions, perhaps?).  It's hard to say.

[rsnellenberger]

I think one Saturn I had it's interstage stay attached to the second stage but it still managed to achieve orbit.

That was the Saturn V launch for Skylab -- IIRC, there was some speculation that debris from the insulation and/or solar panel that were lost might have played a role.

[Dalon]

SpaceX claimed that they were going to do things very differently than the rest of the rocket industry, and cut out a bunch of expensive stuff that wasn't needed but was only done out of conservatism and paranoia.  They have since gone zero-for-three.

Maybe standard rocket industry practice makes sense after all, or maybe SpaceX is doing something uniquely wrong (letting Elon Musk make technical decisions, perhaps?).  It's hard to say.

While it is certainly true that SpaceX has suffered three launch failures, there is zero evidence that these failures have been caused by SpaceX's "better - cheaper - vertical development" methodology.

As has been pointed out by any number of commentators, many of the current breed of commercial launchers suffered similar losses in their early development.  These launchers had gold plated government contracts and funding that in constant dollars greatly exceeded all of SpaceX's expenditures.  The fact remains that that rockets tend to fail until each of their systems are tested in real flight conditions.

I contend that SpaceX's failures have not been because of their "better - cheaper - vertical development" philosophy.  I believe their failures are simply a result of their updating the launch business to current state of the art.  The breaking of new ground is often risky, in rocket science, especially so.  We all know that the smallest of issues can easily doom an entire mission.   SpaceX may now have experienced all of their show-stoppers, they may be on track to deliver their promises.  Then again, it may take another launch or three for them to reach that goal.

You seem to suggest that it is now impossible for SpaceX to deliver on their "Better, Cheaper" goal.  I really don't see how you arrive at this conclusion.  Whenever they achieve reliability, whether it is the next launch, or three launches from now, as long as they do achieve reliability, they should be able to deliver on their promises.

If they end up with a system that has spotty reliability, you may end up being correct.  If however, they are following the prototypical rocket development path of working out the kinks towards the deployment of a highly reliable system, they your contention will be entirely wrong.

History is clearly on the side of SpaceX's merely working through all the show stoppers towards a reliable system, but only time will tell. 

[Seattle Dave]

Reading through this thread everyone seems to be under the impression that launching rockets is easy and a new company like SpaceX should be on the moon by now. 

That's a very strange comment coming from a respected member of this site. I see a few people, as in about three people, thinking this is really bad news for the companies future. I don't see anyone claiming it's easy.

How that is "everyone".......?

[patmamu]

Been reading threw the thread and I tend to agree that it is to be expected Space X will blow up a few rockets. It happens and the computer scientist have yet to simulate Murphy. The only thing I am confused about is why Space X continues to send up live missions instead of boiler plate missions. I would think that if Space X keeps blowing up missions it would become hard to secure insurence on future missions, Insurers are ardly friendly forgiving types. I think Space X should work out the kinks and get a couple of orbitals before they send another mission up on a still unproven rocket. Any way best of luck to Space X and it should be interesting to find out what exactly went wrong.

[pippin]

If they end up with a system that has spotty reliability, you may end up being correct.  If however, they are following the prototypical rocket development path of working out the kinks towards the deployment of a highly reliable system, they your contention will be entirely wrong.

If, however, they are following the prototypical rocket development path of working out the kinks towards the deployment of a highly reliable system, they may end up with a typical rocket industry cost structure in the process.
Which will let you somewhere in between "they will fail" and "they will blow everybody else out of the market".
Which was at least my point here (albeit it obviously has been perceived differently).