In article . com,
says...

On 2016-10-18 08:36, Jeff Findley wrote:

It does when it's an energetic solid oxidizer (can't get much more
energetic than solid oxygen) right next to a solid fuel (carbon fiber).

Ahh. I remember asking early one what could be combusting in the rocket
with LOX leaking and gotten no answer.

I takle it that carbon fibre even when encased in resin is highly
combustible ? is the resin/epoxy also combustible in contact with LOX ?

LOX makes just about anything combustible, but you still need an
ignition source. In this case, the solid oxygen being compressed (with
nowhere to go) inside the composite overwrap is suspected to be the
source of ignition. If it had stayed liquid (i.e. LOX) like on every
other Falcon 9 test firing and flight, it would not have ignited.

(reminder to self: make sure not to spill any LOX on my bicycle :-(

LOX spilled on anything combustible is bad. LOX on clothes will catch
fire. LOX soaked in asphalt is a contact explosive (make your launch
facilities out of concrete!).

Would fibre glass be less explosive or would the resin still provide the
combustible material that would yield the same result ?

Possibly, but fiberglass would be much weaker, and much heavier.

You do that and you have what is called a "contact explosive". The
increase in pressure would cause it to literally explode.


Would it be fair to assume that a breach in the metal coating inside the
tank would have exposed LOX to carbon ?

You're thinking about this all wrong. The helium tank is the COPV. So
the metal bit is containing the helium (else it would leak out of the
composite). The composite overwrap is in contact with the LOX *at all
times*, because the helium tanks are inside the LOX tank. This is
because if your helium tank is inside the LOX tank, it's colder, and can
therefore hold much more helium at its rated pressure than a tank that
is exposed to ambient temperatures (i.e. outside the LOX tank).

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.