SpaceX says helium loading issue caused accident, seeks 2016 return to flight | Hacker News Reader

SpaceX says helium loading issue caused accident, seeks 2016 return to flight

arstechnica.com

66 pointsgvb22 comments

Does anyone know of any good reading on the type of insurance policy SpaceX might have for their launches? Or what type of entity would insure it?

At little old (2002) but just what you are looking for: https://www.faa.gov/about/office_org/headquarters_offices/as...

"issues with handling helium, rather than a design issue with the rocket itself"

I don't know if I would be so quick to declare "rather", but it would mean that they can baby the helium tanks to avoid any design issues for now.

Depends on how you define things. The fact that a gas car will have issues with very cold fuel or fuel outside an octane rating range is not a design flaw. But it is a thing you need to know.

You could say they learned something new about the rocket's exact "needs" and performance envelope, but you could also say that this sensitivity is something that should call for a design rev. Answer is likely yes and yes.

Thus their focus on Raptor, and the ITS using methane and LOX with "hot" O2 and methane to pressurise the propellant tanks.

One it look at it as "avoiding problems with the COPV immersed in cryogenic O2" or "replacing COPV problem with hot gaseous oxidiser problems".

I hope SpaceX learn the important design lessons in develoment and test flights, rather then six flights into their colonisation effort.

Could this explain the loud bang we heard before the rocket exploded?

Boeing sniper nearby, possibly Illuminati.

The solution involves Kevlar armor around all the fuel tanks.

So was it thermal shock?

Formation of oxygen ice crystals around carbon fibers of helium tank, rupturing fibers.

I don't follow /r/spacex so I found this to be a great summary. A little more detail (without going to /r/spacex and wading through threads there) is in a comment (which itself is summarizing theories from /r/spacex) at ars:

http://arstechnica.com/science/2016/10/spacex-says-it-remain...

They don't call it rocket science for nothing. Seems like rocketry is full of issues like that.

I remember reading a bit on the thrusters developed for I think the Apollo program. They had problems a little fuel/oxidizer dribble out of the valves as they were turning on and off. Under some conditions layers of frozen fuel/oxidizer would form on the nozzle. Once enough built up it would explode and shatter the nozzle.

short on -> off -> short on -> off -> long on-> bang

The solution was to carefully avoid those conditions.

No wonder they want to get rid of helium in the new rocket. It's such a pain to work with.

This is what seems to matter most... Company still needs to find "exact" root cause, but ready to resume rocket tests.

They need to figure that out, and they need to do it before they lose another payload on the pad.

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