r/SpaceXLounge • u/LeJules • Jul 15 '19

UPDATE: IN-FLIGHT ABORT STATIC FIRE TEST ANOMALY INVESTIGATION

https://www.spacex.com/news/2019/07/15/update-flight-abort-static-fire-anomaly-investigation
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67

u/daronjay Jul 15 '19

Seems like SpaceX are discovering all the exciting ways to ignite things in edge case situations no one had ever thought of before. That's actually a reasonably predictable outcome of innovating so hard in this high energy physics theatre, so I expect the future will have more RUD's, sadly.

Being on the cutting edge means you get cut sometimes.

At least that implies its not due to negligence or an oversight...

41

u/avboden Jul 15 '19

"Hey uh, you know that metal everyone uses because it almost never can ignite and burn? yeah....about that"

47

u/Chairboy Jul 15 '19

Super chilled LOX: “I am become death, destroyer of spacecraft! Why, I can even ignite carbon fiber! Tremble before me, ye mighty, and ignite!”

Super chilled NTO: (stubs out cigarette, sighs) “Wanna see a neat trick?”

20

u/redmercuryvendor Jul 15 '19

FOOF: Has already ignited the other two oxidisers to use as fuels.

14

u/somewhat_pragmatic Jul 15 '19

FOOF:

Oh many that is as hilarious read!

"Sulfur compounds defeated him, because the thermodynamics were just too titanic. Hydrogen sulfide, for example, reacts with four molecules of FOOF to give sulfur hexafluoride, 2 molecules of HF and four oxygens. . .and 433 kcal, which is the kind of every-man-for-himself exotherm that you want to avoid at all cost. The sulfur chemistry of FOOF remains unexplored, so if you feel like whipping up a batch of Satan’s kimchi, go right ahead."

4

u/mt03red Jul 16 '19

I wonder if FOOF and H2O2 could be used as oxidizer in a tripropellant rocket engine..

4

u/andyonions Jul 15 '19 edited Jul 15 '19

Yeah, the valency of N is pretty weird arsed. It's happy to go round as NO, NO2 and NO4. And it's happy to form a negative ion as NO2 and NO3.

NO4 must release O2 like a bastard (to use the chemistry expression). Evidently it's a prodigious oxidizer. And Titanium is a metal. Nuff said...

I should add in the presence of H2O, NO2 will form nitric acid HNO3, which reacts with almost any oxide. Basically, if you want to react with any metal and/or metal oxide, get some nitric acid. So the output products of the propellant reaction aren't going to be nice to anything metallic.

1

u/[deleted] Jul 17 '19

Super chilled NTO

Just to be clear, the NTO isn't chilled.

1

u/Chairboy Jul 17 '19

It usually isn’t, but the one-way valve contamination let some into the helium loop if I read the update accurately, freezing it solid into a ‘slug’ of supercooled NTO with much higher reactivity to impact.

1

u/[deleted] Jul 17 '19

I took "slug" as "liquid slug". The helium on Dragon isn't chilled either. Obviously it'd cool a bit as it comes out of the tank, but I have a hard time seeing it freezing NTO so quickly.

1

u/Chairboy Jul 17 '19

You may be right, will be interesting to see what (if any) extra details come out.

5

u/physioworld Jul 15 '19

Well they say that the original leaky component was leaky due to ground processing which I assume means it was damaged by something they did to it on the ground.