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SpaceX Launch Failure Due To Timing Problem
FleaPlus writes "Private orbital spaceflight company SpaceX recently announced that last weekend's Falcon 1 rocket launch failure was caused by a collision between the first and second stage of their rocket. This was due to a timing problem, when their brand-new engine design produced residual thrust for 1.5 seconds longer than expected; they're currently working to fix the problem and launch again, perhaps as early as next month. In a recent interview with Wired, SpaceX CEO Elon Musk remarked on their efforts: "Optimism, pessimism, f-ck that; we're going to make it happen. As God is my bloody witness, I'm hell-bent on making it work.""
Silly me. And here I was thinking it was due to a crashing problem...
This guy's the limit!
As God is my bloody witness, I'm hell-bent on making it work.
Something tells me that perhaps he doesn't genuinely, really believe that God is his witness... :)
Is crushing a suspect's child's testicles illegal?
John Yoo: "No, [if] the President thinks he needs to do that."
Optimism, pessimism, f-ck that; we're going to make it happen. As God is my bloody witness, I'm hell-bent on making it work
Now that sounds like a man who gets things done.
Personally, I blame Newton.
Wow, it's like listening to Ahab rant about getting Moby-Dick. Hopefully this will have a better outcome.
"produced residual thrust for 1.5 seconds longer than expected" Cut back on the Viagra next time?
"Optimism, pessimism, f-ck that; we're going to make it happen. As God is my bloody witness, I'm hell-bent on making it work." I can't find a reference to that quote in the wired article or on google.
And I fully expect them to be a major player in the future of commercial space travel.
They've done some absolutely amazing things in the last couple of years on a budget that makes all the governments combined look pretty silly. They remind me of Reid Malenfant and his outfit (only a bit more realistic), and I don't think any issues that crop up during this test stage are going to slow them down for long.
Maybe the 21st century will see some serious space exploration after all, instead of all those 'feel good' missions. $/kg to orbit is the only significant number for the next two decades or so, once there is enough construction capability up there to start hauling stuff inbound it should get interesting indeed.
MP3 Search Engine
"Would you consider that a launch problem or a design problem?"
- Chris Knight
____
~ |rip/\/\aster /\/\onkey
Actually it's got a million and one uses. Torgo's Thespian Powder!
This comment is for entertainment purposes only. Any similarity to real insight or information is purely coincidental.
If NASA had that attitude, we never would have had a decade of stagnation after the first Shuttle accident. We'd have a moon colony by now. The problem is that the people at top too often see these kind of events as a signal to stop, where it really should be a sign that they're almost there. Remember when the Delta rocket flew and then fell over and burst into flames because of failed landing gear? LANDING GEAR! Something trivial to engineer (compared to the rest), and the project is shelved because of that failure. They should have kept going.
Argh. Enough of my ranting, you people get the idea. I just wish the pointy haired bosses did.
I hate to say this, but the CEO has an attitude problem.
He needs to do some reading up on the reviews of NASA after the two shuttle disasters. In both cases overconfidence, and management overruling/ignoring the views of engineers were found to be major factors.
If he keeps running "hell-bent" towards his goal he's never going to reach it.
If NASA had that attitude, we never would have had a decade of stagnation after the first Shuttle accident. We'd have a moon colony by now. The problem is that the people at top too often see these kind of events as a signal to stop, where it really should be a sign that they're almost there. Remember when the Delta rocket flew and then fell over and burst into flames because of failed landing gear? LANDING GEAR! Something trivial to engineer (compared to the rest), and the project is shelved because of that failure. They should have kept going.
Argh. Enough of my ranting, you people get the idea. I just wish the pointy haired bosses did.
if Musk et al. has an accident where someone dies, I bet the FAA and others will be introducing some delays in his schedule. And I'm sure they'll some public outcry that he's flying over people and putting them in jeopardy - whether or not it's true.
We've lost our sense of adventure, the acceptance of risk and, well, we've become a society that's so bent on being safe that we're afraid to take any warranted risks: we've become a society of pansies.
Did it have the mortal remains of any famous actors onboard?
From TFA
the ashes of 208 people, including astronaut Gordon Cooper and James Doohan, the actor who played Scotty in the original Star Trek television show
"Computers are useless. They can only give you answers." - Pablo Picasso
There was a DoD satellite and a NASA thingie on board when it failed.
Also there's plans to make deliveries to ISS once the shuttles are through.
"Computers are useless. They can only give you answers." - Pablo Picasso
I take it he's also going to kick Bishop Brennan up the arse as well for good measure?
Bottom stage detached, continued burning. Less mass against the thrust, it accelerated and pushed on the top stage (but not perfectly centered as it would when still attached).
I'm sure they do communicate, but after detaching that's gone.
Basically the thruster(s) dieseled - continued running for a moment after fuel/whatever was cut.
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
General Patton would have disagreed. He understood the problems faced by his "team" and inspired them to overcome incredible odds. Sometimes a little profanity can be inspiring, if not used gratuitously.
>>Would you like to work for such a man?
Yes, actually I would. Because that sort of man, and the people who work for him, are going to do great things! That's real passion, which is sadly lacking from most corporations. He's not just your average CEO coasting toward a golden parachute and a retirement filled with golf and tea parties -- he's trying to overcome incredible odds to get a vehicle into space.
I AM a Rocket Scientist.
Traditionally, no, they wouldn't be timed individually. That's kind of a silly thing if you asked me.
Typically you should wait until the first stage stop accelerating the rocket before dropping it. A sensor typically detects that condition and initiates seperation. To be safe, it may wait a beat or two before taking action to make sure the booster isn't just "chuffing". Or the sensor could have just been faulty, initiating seperation too soon.
If the booster begins accelerating again (as in blows up) or gives a last burst of unexpected glory, that's just bad design or manufacturing issue. If it's a solid-fuel booster, that could happen from time to time, but if the motor is liquid fueled it should just cut off fuel and be done with it.
Now, you could put the stages on their own timers, but there are risks. Usually the problem is a failed booster, and the timer on the upper stage fires with the rocket pointing the wrong way.
Good objection, but airlines are a little different from space travel for several reasons :
- First, even though there have been a lot of airlines accidents, the numbers are pretty low compared to the number of flights per day. Notice also that the first accident was on 1922, 8 years after the first commercial flight. I think that space travel has a much higher accident/flight ratio. (I admit i don't have numbers to prove it : Wikipedia says that about 4% of people who went to space died inflight, but that includes early flights so it's not exactly the same thing.)
- Second, plane flights were useful to people from the beginning : you could get from point A to point B in much less time than train or boat. Space travel has no such thing : it's a leisure activity. You won't miss a business opportunity if you don't try it.
I think it shows the kind of incredible resolve it takes to do rocket science. I think it's the same resolve the Apollo program had, and I think it's infectious. It's one thing to be balls to the wall but have no demonstrative ability to execute, but remember that Flight 2 actually did make it up there. And that NASA and the US Government have enough confidence in their ability to give them major contracts. For those invoking the Ahab thing, I just don't see that. 5-1 odds they nail it in Flight 4.
according to the interview they have "12 flights ahead of us"
Actually, that's basically what happened. The Kestrel engine on the second stage ignited, and the exhaust from it pushed the first stage away. The problem is that the second stage is designed to have the exhaust expanding into the vacuum of space, and having the first stage right there meant that the exhaust was contained within (or perhaps I should say, was redirected by) the interstage. Normally, the first stage and second stage are pneumatically pushed apart just before the second stage fires.
The exhaust was only in contact with the second stage for a very short period of time, but that was sufficient to "roast" the second stage enough to cause failure, either due to direct thermal effects or the forces created by the expanding exhaust (or to a combination of those factors).
By the way, the nozzle of the Kestrel engine is radiatively cooled. Before the sloshing doomed flight two, it was cool (figuratively only!) to see the bell glowing brightly. Some people watching with me thought it was failing until I explained that it's supposed to look like that. ;)
While I agree that a certain amount of enthusiasm is necessary for a grand undertaking such as this, it is entirely too easy for a manager to be too enthusiastic, ignoring or minimizing serious issues for the sake of maintaining forward progress.
James R. Chiles, in his book Inviting Disaster spends an entire chapter ("Doubtless") on this. He shows time and again how overconfident managers willingly blinded themselves to serious flaws in their programs, and were then surprised when those same flaws came to endanger human life and property.
If I was an investor in SpaceX, I would be asking some very hard questions right now. I would certainly not be accepting Musk's characterization of this issue as a "quirk" or "small problem". SpaceX has had three real launches, in addition to innumerable hours of simulator and modeling time. Why was a serious issue like this not caught earlier? What other mission ending issues are there with the rocket? How confident are the working engineers' answers to the above two questions?
SpaceX is not NASA. They don't have the luxury of an unlimited budget and governmental mandate. As such, their margin for error is correspondingly slimmer, and the board's tolerance for daredevilry should be correspondingly lower.
We all know what to do, but we don't know how to get re-elected once we have done it
Yes, the events are synchronized. Main engine cut-off occurs 1.5 seconds before the stage separation pyros fire.
When engine cut-off occurs, valves close to shut off fuel from the pumps. However, there is still fuel left in the lines that finishes burning resulting in a little residual thrust. In their previous test flight, this finished within that 1.5 seconds. However, this launch used a new engine design.
The previous engine design was ablatively cooled. This means the engine nozzle is kept from melting by small amounts of material continuously burning off and carrying heat away. It's pretty analogous to sweating. The newer Merlin 1C is regeneratively cooled, which increases the performance and efficiency of the engine by running the cold fuel through small pipes that surround the engine nozzle for cooling.
These cooling channels means there's more volume of fuel left in the system at cut-off, and the burn ends up being slightly longer. Musk has stated that this didn't show up as a problem on the test stand because of the pressure difference at sea level versus the near vaccuum where staging occured. 14.7 psi across a half-meter or so rocket nozzle amounts to a few thousand pounds of thrust. However, if you watch the test videos they've published, there's noticeably more flame after cutoff in the regenerative version, so I'm frankly kind of surprised they didn't increase their timing margin.
The end result was that the 1st stage bumped back into the 2nd stage after separation, and then got toasted by and deflected flame back at the 2nd stage, apparently seriously damaging it.
I have to nitpick one of Musk's other statements. He claimed that the performance of the first stage was picture perfect. However, while the engine appeared to perform great, it seems the avionics could have done at least slightly better. The video shows a back and forth rolling motion that is probably due to the torque created as the fuel swirls through those cooling channels. Ideally the control system would have been able to account for that smoothly.