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Elon Musk Asks Twitter For Help In Finding Cause of SpaceX Explosion (gizmodo.com)
On September 1, SpaceX's Falcon 9 rocket exploded on the launch pad at Cape Canaveral, Florida, and destroyed the AMOS-6 satellite that belonged to Facebook, which was going to be used to beam internet to developing parts of the world. Since the cause for the explosion has yet to be solved, SpaceX CEO Elon Musk is asking for help via Twitter. Slashdot reader Thelasko writes: Elon Musk stated on Twitter last night, "Still working on the Falcon fireball investigation. Turning out to be the most difficult and complex failure we have ever had in 14 years." He went on to say, "Important to note that this happened during a routine filling operation. Engines were not on and there was no apparent heat source." Other Tweets mention a "bang" sound before the fire, and that SpaceX "have not ruled out" the possibility that something struck the rocket.
At least one possible explanation.
Proof:
https://www.youtube.com/watch?...
+0 Meh
If you look at the published video on YouTube of the explosion and go frame by frame, there are two events. The first is a bright flash that lasts a few frames and appears much larger than it actually is because it is both saturating the camera and illuminating the condensation clouds. You can see the illumination effect clearly in the first frame the flash appears as there are distinct shadows in the clouds. It's unclear to me whether this triggering event is electrical or chemical in nature, but I'm not an expert. Three observations can be made, however: (1) it is bright enough to cause lens flare in the camera which allows pinpointing its source despite the saturation (look for the X, carefully find its center -- you can do that very accurately -- and then back up a handful of frames; see that triangle thingy with a thin tail? That's what failed.) Then, (2) the initial flash is small and is followed almost immediately by a medium sized flash, and in turn that releases the fireball. Then, (3) the condensation clouds aren't moved by the explosion for about 12 frames until the fireball really starts to form, suggesting that the earlier flashes marked the release of lots of energy that may have been primarily radiation (light) rather than heat because they didn't expand the air enough for me to think of them as explosions. The video is 60 FPS, and the initial flash forms within one frame, so that's only 17 ms. The consdensation clouds don't start moving for 200 ms from the main explosion.
So we have one event that's exceedingly hot that triggers a second that's also exceedingly hot, that releases enough LOX to start the fireball. I'm thinking static discharge from the LOX filling.
One thing I don't understand, though, is that if you watch the fireball in slow motion, as the lower front heads toward the ground, there are seemingly waves passing through it. What are those? Additional shock fronts from tertiary explosions?
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
That's quite a strawman. Nobody thinks government "can't do anything right." The government has obviously done many things right. But can free enterprise do some things better? And better yet, can they do those things on their own dime? We'll see.
We don't have a state-run media we have a media-run state.
Inside LOX tank their are anti slosh baffles made out aluminum which are welded to the inside of the tank. During fueling those welds will be under thermal stress, if one of the welds gave out it would expose Al metal to the LOX then BOOM. The tank material itself reacted with the Pure O2.
It's the nature of the beast when dealing with LOX tanks. 1st)It would be wise to let the tank sit with a pressurized with a couple of psi of O2 for several weeks building up a thicker ceramic AlO2 layer. 2nd) implement a staged cool down procedure before filling tank with cryonic oxygen to reduce stress on welds..