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49 minutes ago, CastleKSide said:

I think there is a substantive difference between uncrewed test flights developing a new vehicle and operation flights of a commercial airliner after approval. 

This. One is a thing where large numbers of passengers are guaranteed to be involved, whereas the other is a proof-of-concept test series where explosions are guaranteed to be involved. It is expected that an airliner should be able to fly for umptillion hours with no incidents, just as it’s expected that SNs will go foof.  
 

Inspiration4 should be carefully observed and regulated. 
DearMoon should be carefully observed and regulated. 
 

But the SN tests should be given a decent amount of leeway as they are, after all, tests, and everything I’ve seen thus far points to SpaceX exercising due diligence with existing safety precautions. We know something’s gonna go boom, they know something’s gonna go boom, but apparently the FAA is all like “you never said anything was gonna go boom!”

And speaking of booms, I predict that there will be no booms tomorrow. In fact, I guaran-ding-dang-diddly-durn-tee it.

Because I’m going to sleep through it. -_-

or it’ll just scrub anyway...

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It's not the oversight I have an issue with. Obviously there needs to be a regulator. And the fact Space X breached the terms of its launch license for SN8 should be expected to have consequences.

But...

A basic level of timeliness ought to be expected. Everyone knew before Friday that a scrub would likely mean a backup day of Monday. This wasn't hard to predict.

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40 minutes ago, RealKerbal3x said:

 

what.

Well, I suppose I didn’t really need to sleep tonight anyway. Still, flying so early in the window would be quite unprecedented, wouldn’t it?

Edited by RyanRising
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6 hours ago, CatastrophicFailure said:

This. One is a thing where large numbers of passengers are guaranteed to be involved, whereas the other is a proof-of-concept test series where explosions are guaranteed to be involved. It is expected that an airliner should be able to fly for umptillion hours with no incidents, just as it’s expected that SNs will go foof.  
 

Inspiration4 should be carefully observed and regulated. 
DearMoon should be carefully observed and regulated. 
 

But the SN tests should be given a decent amount of leeway as they are, after all, tests, and everything I’ve seen thus far points to SpaceX exercising due diligence with existing safety precautions. We know something’s gonna go boom, they know something’s gonna go boom, but apparently the FAA is all like “you never said anything was gonna go boom!”

And speaking of booms, I predict that there will be no booms tomorrow. In fact, I guaran-ding-dang-diddly-durn-tee it.

Because I’m going to sleep through it. -_-

or it’ll just scrub anyway...

From memory of the news reports I saw months ago, the story with the 737 crashes from the last few years was that Boeing told the FAA that they had taken certain precautions to ensure that single angle of attack sensors wouldn't cause problems even if the sensors failed, and the FAA took Boeing at its word.   However during the investigation into those crashes FAA discovered that Boeing hadn't taken done that.  Hence the fuss about the FAA under-regulating the industry.  (Note that is from memory of news reports, so I've probably got some details wrong, but hopefully the gist is right).

Now with SpaceX and Starship, I'm guessing/hoping that they are checking that SpaceX has appropriately calculated the blast effects and taken appropriate precautions in case the Starship explodes on the pad or 5 seconds after liftoff,  or if one or more flaps seizes up during decent, and SpaceX loses control.

 

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One of the Raptors was definitely burning fuel-rich again...could this have been a smaller part of a more significant problem leading to the RUD?

Edited by Lewie
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11 minutes ago, Lewie said:

One of the Raptors was definitely burning fuel-rich again...could this have been a smaller part of a more significant problem leading to the RUD?

This looked less fuel-rich and more engine-rich.

That pipe with the little silver wrap around it is the manifold that takes cold liquid methane from the turbopump outlet and pipes it into the regenerative cooling channels. It is the highest-pressure point on the fuel side of the engine.

I'm not sure if that's what was burning or if that's just where the flames ended up swirling. But it's definitely off-nominal. And you can see that they switch to the LOX tank view almost immediately.

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Obviously I am not a rocket scientist (although reasonable minds may differ) so I could only guess...

...but if I had to wildly speculate based solely on Elon's tweets and the available footage, I would say that Engine 2 had some sort of ground debris damage or a burn-through affecting the cold fuel manifold at the CH4 turbopump outlet. This started an external fire. Engine 2 is the second engine to shut down, so the fire continued for quite some time (you can see this later in the video, from another angle). They were having video issues and so we do not see Engine 2 shut down. As SN11 crosses 1 km altitude, we have a split-second shot of Engine 1 beginning to ignite, and then it freezes.

Because Elon says that Engine 2 "didn't reach operating chamber pressure during landing burn", I suspect this means Engines 1 and 3 did reach full chamber pressure, but Engine 2's turbopump failed catastrophically at startup due to the fire damage and fragged the other two engines. Falcon 9's octaweb includes frag shields between engines, but there are no shields between engines on Starship. Losing the other two engines would have resulted in the system immediately realizing it couldn't land and triggering the FTS.

The poor video was probably just the result of fog and no other issues.

2 minutes ago, RCgothic said:

This is cool for free-flight missions:

Huh. The Dragon docking port is androgynous so I would have expected that free-flight missions would still retain the port for contingency.

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