SpaceX rocket: Explosion at Kennedy Space Center

[tionis]

They just lost a rocket:
SpaceX[/PLAIN] rocket: Explosion at Kennedy Space Center ahead of launch



[PLAIN]http://www.bbc.com/news/world-us-canada-37247077[/PLAIN]

 

[phinds]

Bummer.

 

[mfb]

The launch pad is still smoking. Current image (gets updated frequently). Several parts there got damaged and will need repair. The hydrazine of the satellite (which was on board already) also exploded, it is unclear if that was the first explosion (indicating a problem with the payload) or not (indicating a problem with either the rocket or the launch pad infrastructure). A problem with the payload would be the best case for SpaceX, as it would mean they just have to repair the launch pad and build a new rocket. A problem with the ground infrastructure is worse, then they have to find and fix that. And a problem with the rocket is the worst - that's what we had last year, which delayed everything by 6 months.

 

[berkeman]

So was that a previously used first stage? It sounds like it from the article, but I may be misreading it.

 

[mheslep]

The accident at the Cape introduces a more severe problem than how to repair / replace for the current launch. In connection with the earlier accident during boost, it suggests a possibly pathological problem with safety. SpaceX has Falcon Heavy and the *manned* Dragon on the table. Now, those systems can't responsibly be made operational until SpaceX identifies systematically what enabled an on the pad catastrophic accident and then retrofits the coming programs accordingly. Of what use are the various emergence escape measures for, say, Dragon for an on the pad failure.

 

[mfb]

It was a new first stage.
The previously flown stage was scheduled for a flight in mid October.

it suggests a possibly pathological problem with safety.

Does it? Unmanned rockets typically have a 5% loss rate (counting from a lauch attempt). SpaceX lost one Falcon 9 out of 28. Even if we include this mission (then we should also change the 5% but I don't know the number then), we have 2 out of 29 - above the average, but not significantly. If those missions would have been manned, the crew would have survived in both cases - in the first case the Dragon capsule survived the explosion even without an abort system, and in the second case the crew would not have been on board.

There were 312 manned launch attempts so far, two of them failed, the launch escape system rescued the crew in one of them (a Russian rocket that exploded on the launch pad). That makes one loss out of 312 crews - higher than what SpaceX would have delivered, although the difference is not significant of course.
There were also three landing attempts that ended fatally - one Space Shuttle, one Soyuz that crashed into the ground, and one Soyuz that lost its interior pressure while still in space. The last one killed 3 astronauts, to the only deaths in space so far.

Of course they will... of course they are investigating the explosions already to figure out what went wrong. Last time they had a good idea after just 2 days, and could reproduce it in their test stands after 2 days more. Then they spend several months improving everything and checking it over and over again.

 

[nsaspook]

Massive! Looks like it started just under the payload. You can see both of the towers smoking from the blast.

 

[russ_watters]

The launch pad is still smoking. Current image (gets updated frequently). Several parts there got damaged and will need repair. The hydrazine of the satellite (which was on board already) also exploded, it is unclear if that was the first explosion...

Isn't that the intact payload package falling off the rocket at the 12 second mark in the first video? Looks like a cook-off later for the payload package.

Reliability is a dicey thing for any new system and NASA had a lot of failures early-on. I'm not sure if that is as acceptable today though as it was 70 years ago when we were just trying to be first.

 

[mheslep]

Does it? Unmanned rockets typically have a 5% loss rate (counting from a lauch attempt).

Over what period? These two Falcon accidents are 13 months apart.

...There were 312 manned launch attempts so far, two of them failed, the launch escape system rescued the crew in one of them (a Russian rocket that exploded on the launch pad). That makes one loss out of 312 crews - higher than what SpaceX would have delivered, although the difference is not significant of course.
There were also three landing attempts that ended fatally - one Space Shuttle, one Soyuz that crashed into the ground, and one Soyuz that lost its interior pressure while still in space. The last one killed 3 astronauts, to the only deaths in space so far.

I count 21 fatalities due to accidents in a particular spacecraft design (including the three Americans in Apollo 1 due to the pure O2 atmosphere), regardless of the mission stage.

Of course they will... of course they are investigating the explosions already to figure out what went wrong. Last time they had a good idea after just 2 days, and could reproduce it in their test stands after 2 days more. Then they spend several months improving everything and checking it over and over again.

Finding a particular problem and and fixing it is necessary but insufficient for critical operations. For example, finding in the June 2015 accident that the mechanical support for the O2 tank was underrated for load was necessary but insufficient. They also have to determine what was flawed in their process and system design that allowed the mistake to happen in the first place; it is this latter issue which might/might not be pathological. With NASA in the Challenger days the report findings labeled the problem "go fever".

 

[1oldman2]

http://www.planetary.org/blogs/jason-davis/2016/20160901-falcon9-pad-explosion.html

The launch window for the Falcon 9 was scheduled to open at 3 a.m. EDT on Saturday, Sept. 3.
SpaceX regularly conducts a "static fire" test a couple days before launch, during which the
rocket remains held to the pad while the engines fire up for a few seconds. Today's accident
originated near the rocket's upper stage oxygen tank, which was being pressurized in
preparation for the firing. It remains unclear whether the accident was caused by the rocket, the
launch pad infrastructure or a combination of both.

 

[nsaspook]

This little bit of news on who pays.

https://twitter.com/pbdes

1. Peter B. de Selding ‏@pbdes 5h5 hours ago
   Spacecom insured Amos-6 for $285M in marine cargo market, not space insurance market. Launch +1 yr policy would kick in at rocket ignition.
   
   66 retweets47 likes
   
2. 
   https://pbs.twimg.com/profile_images/453570375889068032/ectA_OPy_bigger.jpeg Peter B. de Selding ‏@pbdes 5h5 hours ago
   SpaceX explosion didnt involve intentional ignition - E Musk said occurred during 2d stage fueling - & isn't covered by launch insurance.

http://www.cnbc.com/2016/09/01/when-a-rocket-blows-up-space-insurers-pay-for-it.html

 

[mheslep]

There's most always opportunity cost as well.

Zuckerburg's comment on the loss of his satellite suggests there is a larger loss than that of the hardware. Facebook stands to lose the promotion of their platform, for a period, into regions where that satellite would have put them. If someone else beats them to it, then Facebook forever loses being first into those areas.

 

[mheslep]

A NASA advisory committee warned about the safety hazards of SpaceX's fueling procedures, some time before this accident. The committee objected to the refueling procedure for manned missions.

Paywalled:
http://www.wsj.com/articles/nasa-ad...-about-spacex-rocket-fueling-plans-1477955860

In contrast to traditional procedures, SpaceX plans to seat it's astronauts first and then fuel. The order of events is made necessary by Spacex's use of supercooled LOX, which apparently has a short, use it or lose it time limit once loaded into the vehicle tanks, too short to allow astronaut seating post fueling.

I imagine this is going be a challenging problem to resolve, with supercooled fuels inherent to the Falcon design (or all SpaceX designs?). Supercooling improves density, enabling a greater fuel volume, supposedly one the innovations that enables the booster landings.