Talk-Polywell.org

I do have to say it doesn't look like a fuel or LOX ignition. The detonation is near-instantaneous and is nearly 50 feet across in one frame (1/30th of a second). Kerosene doesn't burn that color, and LOX would need something to burn, which, given the steel construction and sparse umbilicals, I just don't see a source.

However, what it could easily be, is one of the abort explosives detonating prematurely. One of the early comments said that a "catastrophic abort had occurred after an anomaly." If someone leaned on the big, red button by accident...

1:11 (frame 3) 1:11 (frame 4) Given that the fairing is 5m across, that fireball is nearly 15m tall and 10m wide in less than 1/30th of a second. And with a pure yellow-white fire like that, it's not a ruptured pressure tank, or kerosene burning in air. You don't see that color again until the kerosene spraying from the first stage covers an area over a hundred meters wide and you finally get a fuel/air mix that allows fast, hot combustion.

The initial explosion seems to have a single origin. Doesn't the flight termination system involve line charges along the tanks?

The FTS charges are normally not meant to cause an explosion but to "unzip" the rocket releasing the fuel.
The source of the explosion seems to be near the LOX tank of the second stage, but I dont think it is the tank itself. Even if there was a leak, something needs to spark the explosion. Maybe some freak electric failure? The stage is venting LOX at that spot where the explosion started...

It sure looked to me as if it could be a destruct charge.

Recalling flight termination tests I've been involved with, I can say NASA is real persnickety about them. Testing the flight termination system (FTS) is part of of preflight, and it is a "hold your breath" time. In our case we were just dealing with a couple of small pyro cable-cutters, but we had no replacements and a false trigger would have meant a huge delay. For destruct charges, it means smoking debris.

We had to prove the FTS could be triggered by radio, and also by a couple of self-destruct conditions in our onboard software. That had to be done with the pyros in place, but we could disconnect them and have shorting plugs across them. For the tests we could substitute a light bulb for the pyro. But after verifying that the destruct signals got thru, we had to connect the pyros up and verify continuity. With destruct charges, all that needs to be done remotely. The design needs to err on the side of being a reliable destruct mechanism, with no chance the disconnect-and-short safeties will prevent destruction when needed.

If the FTS tests were underway when this happened, I expect a pretty short investigation, but either a procedure change or FTS re-design.

If it did not occur during an FTS test, this could take a while. But pure O2 and LOX are serious explosive hazards. LOX and about anything combustible make an explosive that can blow up mountains (LOX and sawdust or flour have been used this way so that if a charge failed to go off, it would be rendered safe by evaporating off the oxygen). LOX and bagels literally can move mountains!

your quadcopter looks like a big old florida bug to me.

But the color of the flame is interesting , nitrogen tetroxide and mono methyl hydrazine? AKA satellite fuel


note if you click on the gear in youtube you can slow the video to 1/4 spped and see a bunch of stuff shooting away as the explosion occurs.

I concede that Florida bugs are big enough to fly around with .50 cals.


(From nasaspaceflight.com thread.)

Ah, but it turns out this was NOT an explosion. Apparently this was a "fast fire". I'm sure this will also be couched as an "unscheduled disassembly". Glad we cleared that up!

LA Times: "Elon Musk says fireball on launchpad was 'not an explosion' ... Musk also says SpaceX's Dragon capsule would have withstood the flames that destroyed the Amos 6 satellite.

It turns out this "fast fire" is just one thing that went wrong for Musk today.

Is he a drinking man? He may need a stiff one when he gets home.

http://www.bloomberg.com/news/articles/ ... illion-day

I don't picture the loss of personal wealth meaning much to Musk except as it relates to being a tool to aid him in changing the world. I think what his companies can do for humanity is probably all that matters to him. After all, doesn't he work every waking hour? How could he possibly have time to spend his money?

DeltaV wrote:I concede that Florida bugs are big enough to fly around with .50 cals.


(From nasaspaceflight.com thread.)

X = vapor backlit by explosion?

Tom Ligon wrote:Ah, but it turns out this was NOT an explosion. Apparently this was a "fast fire".

It's actually quite important from an investigative point of view.
If they already clarified that it was a fast fire than its more possible that the cause of failure was due to an unprotected electronic part (or a static electricity build up or a mechanical friction) that set up an unexpected spark, similar to what normally happens in an hyperbaric chamber explosion.

Tom Ligon wrote:If it did not occur during an FTS test, this could take a while. But pure O2 and LOX are serious explosive hazards. LOX and about anything combustible make an explosive that can blow up mountains (LOX and sawdust or flour have been used this way so that if a charge failed to go off, it would be rendered safe by evaporating off the oxygen). LOX and bagels literally can move mountains!

But what was the fuel involved? Based on the speed of the initial fire it had to be something that would mix with air or O2 before the ignition hit.

Was SpaceX rocket hit by a drone? Shock claims Elon Musk’s Falcon 9 was 'attacked'

Commenting on the YouTube video, Scott Keller wrote: “One person said it was a bug. Someone else a bird.

“Hard to accept those two as explanations. Too fast and not close to the camera.”

Rantin Wraithy wrote: “That’s a big f****** bird. And round too. I didn’t think ostriches could fly.”

http://www.dailystar.co.uk/news/latest- ... 9-attacked

simple enough to figure out, If you have another camera view and its not there its a bug. If it is there then you can figure out range, bearing , size and speed.

https://www.youtube.com/watch?v=Ye0EOENUw0c
This video syncs the sound and the explosion. It also pinpoint the point of start of the fire.
my favorite quote so far
Don't worry guys, it only blew up something important and then fell on something expensive.