totm nov 2023 SpaceX Discussion Thread

[RCgothic]

My puzzle is that an engine would need to run LOX rich for quite a while to fall catastrophically. Surely they could just... turn the engine off? Which begs the question why didn't they?

Also whilst it's probably worth trying, low lox levels in the tank for a static fire probably wouldn't be sufficient to replicate the long duration and high G environment that may be causing harmonic vibration issues in flight in the ground.

[GuessingEveryDay]

Crew-10 delayed

[darthgently]

3 hours ago, RCgothic said:

 

My puzzle is that an engine would need to run LOX rich for quite a while to fall catastrophically. Surely they could just... turn the engine off? Which begs the question why didn't they?

 

The remaining engines not shutting off really is a puzzler.  But that assumes the software has a totally clear idea of what was happening back in the engine bay.  If it assumed some vectoring engines were still operating the goal may have been to regain attitude, keep chugging, and get the debris field out into the mid Atlantic instead of in the islands.

 It broke one of my KSP rules:  never thrust in the wrong direction.  My kOS scripts typically taper the throttle as attitude error goes up as a safety net.  No throttle, or just enough for vectoring steerage, if error is greater than 20 degrees or so on ascent.  This code typically only kicks in when I’m doing something new but it allows me to keep playing and testing for awhile rather than crashing and starting over.  Anyway, the point is that I’m not sure why they didn’t shut the remaining engines off, or at least throttle them down when pointed in the wrong direction.  They may have made it well past the islands, even doing endos, if they only throttled up when pointed down range with a positive pitch and tapered throttle down when not.  And maybe the engines were on for an reason but the software was confused about the attitude and available control authority

[tater]

 

[Exoscientist]

 
 Repeated engineering failures stem from the top. What SpaceX needs to do first is hire a true  Chief Engineer. Then follow standard industry practice of doing full-up(all engines), full mission duration, full thrust static tests.

  Bob Clark

[AckSed]

What is a true Chief Engineer?

Do they have aerospace experience?

Are they a respected expert in their field?

Do they have at least ten years of working at a rocket company?

Are they experienced with a high-pressure environment as they work with a team to push boundaries?

And are they also sensible and know when not to push the boundaries?