SpaceX Dragon 2 capsule destroyed in abort motor ground test

JF Mezei wrote on Sat, 4 May 2019
18:45:28 -0400:

fron:

https://youtu.be/s6a9Ct9O_nY

(NASA press conference on launch of cargo Dragon, they discussed Dragon
2 "anomaly".

"just prior, before we wanted to fire the Super Draco, there was an
anomaly and the vehicle was destroyed"

"anomaly occured during activation of the Super Draco system".

"we have no reason to believe tht there is an issue with the Super Draco
themselves", "those have gone thorugh about 600 tests".


I'm pretty sure several of us told you that right after the anomaly
happened.


The way I interpret the SpaceX spokesperson's words:

-The engines are not at issue.


You don't know that. "No reason to believe" does not mean "not". It
just means that like the COPVs it's a lower probability. But we're
not playing "guess the most probable thing". We're playing "what the
**** went wrong so we can prevent it from happening again, regardless
of how likely it was".


-use of word "system" points to when they "booted" the system, not when
they pressed the the big red button to get fuel to the engines.


Right conclusion but wrong reason. Your key is 'activation', not
'system'. And that still doesn't guarantee it wasn't a combustion
chamber failure. For example, you pressurize the propellant tanks and
a throttle valve fails. That puts propellant under pressure in the
combustion chamber.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn