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SpaceX Comm/Facebook Satellite toast.
3

SpaceX Comm/Facebook Satellite toast.

RE: SpaceX Comm/Facebook Satellite toast.

At least this has nothing to do with the reuse of a returned booster. This is 'just' a normal rocket science failure. If their first reuse booster had exploded, then the repercussions might have derailed that aspect of their future plans.

Even still, the launch complex will be closed for months...

RE: SpaceX Comm/Facebook Satellite toast.

(OP)
Oh oh!! A much better video.

https://www.youtube.com/watch?v=_BgJEXQkjNQ

It's sooOO cool(hot?) to see all the paint facing the launch pad on the lightning diverters flashing into gas, then being sucked into the updraft caused by the bazillion kilocalorie fireball. Watch for it just after the big fireball.

Keith Cress
kcress - http://www.flaminsystems.com

RE: SpaceX Comm/Facebook Satellite toast.

From talking with some Space-X people a year or so ago, there were comments made that Musk was not very happy with the reliability of valves purchased from various manufacturers out there and while I have no direct knowledge of the current situation, the rumor at the time was that he was considering cutting-out the middleman and producing them himself as a way of getting better control of the quality. After all, when Space-X had the chance to purchase 3rd party rocket engines Musk opted to have them designed and built in-house.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: SpaceX Comm/Facebook Satellite toast.

Space is hard.

RE: SpaceX Comm/Facebook Satellite toast.

Chinese valves?

Mike McCann, PE, SE (WA)


RE: SpaceX Comm/Facebook Satellite toast.

Have you seen that the Chinese are going to start making jet engines for passenger planes?

Funny that we have been building rocket engines since the 60's, and we can't just follow an older engine design?

But this looked like it was above the engines, or maybe the last stage.

RE: SpaceX Comm/Facebook Satellite toast.

It's been stated to have been a failure during fuel transfer to the second stage.

RE: SpaceX Comm/Facebook Satellite toast.

Why do a static firing of the main (1st stage) with a second stage loaded? My son told me (dunno if true) that the payload spacecraft had been loaded as well...again why risk the payload for a static firing test? And why load propellants in 2nd stage?

Sheesh, risk management must not be a subject at SpaceX.

RE: SpaceX Comm/Facebook Satellite toast.

Then again, it may not be just SpaceX, since we can ask "why launch with solid rockets that have a history of partially burning thru their seals", and "why launch in cold weather when you have a history of ice buildup and subsequent breakup debris impacting the structure at launch" and "why launch without the repair kits for the reentry vehicle that you developed and included on the first few launches".

Space is hard enough without MBAs making the decisions.

RE: SpaceX Comm/Facebook Satellite toast.

Just a guess, but the payload is at the top, so it was placed on the rocket prior to it being moved into place. Maybe a crane issue?

It appears failure is an option, but not a choice. Then again we don't do these things because they are easy, but because they are hard (The last part?).

RE: SpaceX Comm/Facebook Satellite toast.

Star for btrueblood.

Static fire test results: positive for fire; is that a success to an MBA?

Risking the payload for a static test sounds colossally stupid on its face.

Mike Halloran
Pembroke Pines, FL, USA

RE: SpaceX Comm/Facebook Satellite toast.

An obvious attempt to save time... that failed.

Or...Overconfidence?

Mike McCann, PE, SE (WA)


RE: SpaceX Comm/Facebook Satellite toast.

Quote (btrueblood)

Why do a static firing of the main (1st stage) with a second stage loaded? My son told me (dunno if true) that the payload spacecraft had been loaded as well...again why risk the payload for a static firing test? And why load propellants in 2nd stage?

Sheesh, risk management must not be a subject at SpaceX.

(I'm definitely not a rocket engineer, just an enthusiast) I believe 2nd stage is integrated and fueled to test the fuel loading and associated hardware on the 2nd stage. As for the payload they recently got approved by their insurance to integrate the payload before the static fire which apparently saves them a day of work. Obviously that was a bad idea and I suspect they will be doing some re-evaluation of risk management to avoid one accident turning into many others.

I wonder if rushing to try to save days was a result of the failure of CRS-7 and trying to catch up to their launch schedule.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries
www.americanconcrete.com

RE: SpaceX Comm/Facebook Satellite toast.

The gap between simulation and reality is filled with chasms. The 787 is a poster child for that; model-based design and simulation still didn't keep the plane from having a multitude of problems that put the plane more than 2 years behind production release schedule.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers

RE: SpaceX Comm/Facebook Satellite toast.

Space is hard
Pushing the boundaries is harder
SpaceX is the first one to use sub-cooled LOX and chilled RP1.
They do this to get more fuel in the rocket; more fuel in the rocket works to defy the tyranny of the rocket equation. Everyone else (NASA, ULA, ESA, China, Russia as far as I can tell) uses LOX at boiling point, so there is a lot of experience there, but the experience is limited on LOX near the freezing point especially for high volume handling of the stuff. O2 melting/freezing point -361°F, Boiling/condensing point -297°F. That extra 64 degrees can make the difference in piping, hoses, valves, you name it.

As for why load the second stage, the static fire test is more than just a test of the first stage engines, it is a test of the entire launch procedure, so doing everything as if it were a real launch is part of the test. Their corrective actions during a launch is very limited due to the design of the booster, they want to launch on the first second of the window otherwise the too much LOX warms up and boils off and the RP1 will also warm up and spill out. Doing a full launch test during the static fire test proves out the other procedures so launch day goes smoother.

Good luck to SpaceX to finding the cause and the causes behind the cause.

Hydrae

RE: SpaceX Comm/Facebook Satellite toast.

(OP)
I'm guessing the fully stacked testing is expected to prove the engine thrust, fuel valves, pressure sensors, and the full launch vehicle's electrical connections are not vibrating apart. It's not expected to be a blow-up event like the much more hazardous launch is. Indeed it seems like the problem was completely unrelated to the vehicle and really a plumbing-to-the-vehicle issue. That's why I think the payload is present and will continue to be present in all future missions.

Looking at the initial explosion you can see, what probably is, a pipe fitting being launched up and away from the fueling connection area.
Note the two pieces in this frame.



I wonder if someone left a greasy fingerprint somewhere that the LOX took offense at.

Keith Cress
kcress - http://www.flaminsystems.com

RE: SpaceX Comm/Facebook Satellite toast.

So, is it too much of a weight penalty to put a capsule-lauch emergency booster on the satellite capsule for such a test?

If the static test is satisfactory, then you unbolt and remove the safety rocket before the real launch. Or leave it on the capsule to recover the satellite if the main rocket goes off at the real launch.

Or, after a few seconds of flight, use the thrust from the emergency rocket to add a few lbs of thrust while in flight. Then eject the empty safety rocket.

RE: SpaceX Comm/Facebook Satellite toast.

The fairing over the satellite isn't much more than a dome, designed to resist aerodynamic pressures only.
Attaching an escape tower on top of it (a la mercury capsule) would require substantial reinforcement of the fairing to allow it to support the weight of the satellite multiplied by the lift-off acceleration of the escape rockets. That will be many more times the load the fairing can handle without substantial reinforcement.
And then there's the matter of landing the escaped capsule safely...
This is complex and expensive enough that I think it's only been justified for capsules carrying humans.

STF

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