Yes, but... As I understand it, aluminum in LOX very much tends not to
catch fire absent significant heat and/or a mechanical impact or tear
that exposes unoxidized aluminum directly to LOX.
Which brings us back to, where'd the initial energy for that heat or
impact or tear (or for whatever sequence of events led to the visible
explosion) come from in the first place?
A rag or other flammable foreign object inside the LOX system seems one
plausible candidate for the initial energy in this accident.
An internal LOX leak rendering some internal stage component (or rag or
other flammable foreign object) flammable/explosive also may have a
place on this list.
Ditto an external LOX leak rendering some external stage or tower
component flammable/explosive.
A mechanical failure in the high-pressure HE system is of course an
obvious candidate. (Note it wouldn't have to be an actual pressure
vessel - overpressurizing a propellant tank aside, a loose or broken He
plumbing line could whip around at high enough velocity to produce
significant impact damage.)
Just for completeness, a range-safety explosive charge could also
provide the initial energy.
Have I missed anything?
Leaving aside of course the apparently
near-impossible-due-to-extremely-sparse-data question of evaluating
relative probabilities among these possible source of initial energy.
Henry
On 9/11/2016 3:04 PM, Evan Daniel wrote:
Couldn't a fire that started internal to the LOX tank / plumbing
behave similarly? Those Al-Li alloys are flammable in LOX, right?
Evan Daniel
On Sun, Sep 11, 2016 at 5:49 PM, Jake Anderson
<dmarc-noreply@xxxxxxxxxxxxx> wrote:
On 12/09/16 06:36, Henry Spencer wrote:
Still an already brittle composite is going to get more brittle at cryo
On Sun, 11 Sep 2016, Keith Henson wrote:
I wonder what the loading sequence is? The thermal stress would be
awful on a sphere where half was a room temperature and the other half
was at LOX temp.
The usual sequence for helium bottles inside cryo tanks is to load the
helium last and unload it first. Most materials get stronger at low
temperatures, and of course gases are denser when cold, so you can get a lot
more helium in if you fill cold bottles with cold helium.
Henry
temps.
It looks like it goes from nothing to about 1.5x the diameter of the rocket
in 1 frame (at 60fps) then it seems to be just fuel + oxidiser burning to
me.
Weather its those specific tanks or something else my money is on something
small and high pressure letting go.
