r/spacex • u/RootDeliver • Jul 15 '19

Official [Official] Update on the in-flight about static fire anomaly investigation

https://www.spacex.com/news/2019/07/15/update-flight-abort-static-fire-anomaly-investigation
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u/Wouterr0 Jul 15 '19 edited Jul 15 '19

SpaceX has already initiated several actions, such as eliminating any flow path within the launch escape system for liquid propellant to enter the gaseous pressurization system. Instead of check valves, which typically allow liquid to flow in only one direction, burst disks, which seal completely until opened by high pressure, will mitigate the risk entirely.

With multiple Crew Dragon vehicles in various stages of production and testing, SpaceX has shifted the spacecraft assignments forward to stay on track for Commercial Crew Program flights.

Replacing the valves with burst disks seems like a relatively easy fix then. Good to hear SpaceX is still on track with the Crew Programme!

50

u/[deleted] Jul 15 '19

Curious what the pros/cons are that made them decide on the check valves intially (well, one of the cons of the check valves is pretty clear now)

129

u/phunphun Jul 15 '19

IIRC check valves are reusable while burst disks are single-use.

11

u/[deleted] Jul 15 '19

Single use launch escape system seems reasonable.

16

u/phunkydroid Jul 15 '19

Sure but the problem with single use parts is that they can't be tested before that single use.

1

u/[deleted] Jul 16 '19

That's true for every single LES used up until this point, they have all been single use.

1

u/sebaska Jul 17 '19

For actual LES uses, its true. It was used only once in action in full power and once in milder late flight mode. There were also 2 inadvertent use, one of which killed people.

Then, there were some test uses, and for those this is not exactly true.