>> david, what do you make of this assessment what richard and miles say, where do you stand? >> where i stand on it is there's nothing -- first of all it's established that there's no given yes or no. there's no black and white to this. but my best assessment is that there was a mechanical failure. there's a history of the oxygen tank in this particular model of aircraft that's failed before that's caused a rapid decompression -- well a break in the hull that would have caused a rapid decompression. this has happened before. it could have easily happened again. luckily, before it was happening on the ramp where it would have stopped at that point. there's history of another airplane where everyone on board the aircraft died of apoxia and one person stayed alive using medical oxygen and was able to make his way forward while the f-16s thought the aircraft was disabled followed this airplane and noticed someone was moving in the airplane. that person pulled the pilot out of the cockpit, got in the seat and was ready to navigate and