take down an aircraft over 30,000 feet. this plane itself was over 30,000 in sinai. i don't know if a terrorist group that has the capability to do that. that is a serious piece of equipment with some people that had a lot of training. you can't just roll something out and take a plane like that down at that altitude if you're a terror group. >> so just to explain for our viewers a surface-to-air missile that you put over your shoulder. >> can't do it. >> rpg. >> not enough. >> mary, the plane dropped off the radar 23 minutes into the flight well after takeoff, does that timing give you any clue about whether or not it was a mechanical issue or something else? >> well, unfortunately the timing puts it squarely into either camp. it could squarely be in mechanical issue. i can name several crashs that have a signature like that. tw-800 for one it was a few minutes into the flight, gotten up to -- it wasn't as high as this but then a catastrophic explosion in the fuel tank brought it down. also the loss of a structural member, loss of a tail like american airlines 587 of the