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SpaceX Plans To Resume Launches In November (reuters.com)
An anonymous reader quotes a report from Reuters: SpaceX is aiming to resume flights in November following a launch pad fire that destroyed a Falcon 9 rocket and an Israeli communications satellite it was due to lift into orbit, the company's president said on Tuesday. The space services company suspended Falcon 9 flights while it investigates why the rocket burst into flames on Sept 1 as it was being fueled for a routine prelaunch test at Cape Canaveral Air Force Station in Florida. "We're anticipating being down for about three months, getting back to flight in the November timeframe," Gwynne Shotwell, president of Elon Musk's space company, said at a satellite industry conference in Paris. SpaceX previously said a nearly-completed second launch site in Florida, located at NASA's Kennedy Space Center (KSC), would be finished in November. The pad was last used to launch NASA's space shuttles five years ago.
Zero.
You seem awfully sure about that, there are .50 cal sniper rifles in civilian hands that can shoot through a window at 2500 meters.
There was a bang right before the explosion. What are the chances the rocket was shot at?
A bullet from a sniper rifle typically travels in excess of 1000 m/s, or about 3 times the speed of sound. So the "bang" would have come after the explosion.
There would have been two 'bangs' perceived by people at the site of the rocket, the sound of the bullet smacking into the rocket followed by the report of the rifle which could have been over two kilometres away if he was firing a .50 cal. Against a target the size of that rocket and with a fair idea of what the wind is like along the path of the bullet a good sniper could have made a 2000 m shot, possibly even a longer one. However, At 2000 m there is no guarantee the muzzle report would have been noticed at the site of the rocket, especially if the shooter made efforts to suppress the muzzle report. Having said all of this I think a sniper is the least likely suspect... Occam's razor...
The NASA spaceflight forum is up to about 136 *pages* of people debating theories on the subject. A lof of the more recent comments have focused on a particularity that only applies to SpaceX and not any other rocket in the world: their densified / superchilled LOX. The only other rockets to have ever used any sort of densified LOX have been the NK-33 variants, all of which have very short, very poor test/flight records - and their LOX wasn't as densified as SpaceX's. A unique risk of densified LOX is air liquefaction; it's colder than the boiling point of both oxygen and nitrogen - and nitrogen tends to boiloff first, or not form at all if the surface in contact with air isn't as cold as the densified LOX itself. You can see LOX forming straight from air by pouring liquid nitrogen into an uninsulated, thin-walled metal container (aka, a rocket) and letting it sit; droplets form on the side and slowly drip off.
Like is common with non-densified LOX, SpaceX has no insulation on its stages, apart from any frosts that form. And frosts do not form a rigid layer, nor are they a comparable insulation to foam. There is one type of propellant that has long faced challenges with air liquefaction: liquid hydrogen. And liquid hydrogen tanks are always insulated. In part it's to avoid the air liquefaction from drawing heat out of the hydrogen, but it's also in part for safety and to prevent liquid air from collecting in vents, in the interstage, etc and adding weight.
If there's LOX outside the tanks, that's a serious potential hazard. If there were leaked fuel vapours (for example, hydrazine from the payload, RP-1 from the stage, etc), or if it collected on top of an organic material on the strongback, or even with Falcon's paint itself, that's a major potential hazard for a serious, rapid deflagration.
Some of the other theories are internal. LOX contamination is a common one. Tank contamination is another. Another is failure of the COPV (the helium pressurant container). Another is a common bulkhead failure. I'm sure these things will all be debated endlessly until the actual investigation results come out.
It's neat to see the lengths people go to through to try to get data without access to the official investigation data. For example, they've brought in a seismologist who's been going over results from seismic stations in the area, looking at the S and P waves and what they could correspond to. Lots of people have been working on processing the video in different ways to try to bring out details. I myself am trying to get ahold of the raw video footage; I suspect it may have been interlaced as well as having a rolling shutter, but have been deinterlaced in all of the subsequent processing. If so, it may be possible to bring out a whole extra frame, plus limited details at sub-millisecond accuracy.
All just idle work of course; the real work is going on at SpaceX.
"I need swat, tactical, the guys with the flashlights on their guns, those guys with the big shield thingies"