accidents that give clues how this might have happened. and what occurs is you're flying your own course. you do have other waypoints, other alternates entered in but only safeties. for example, this if you can't get into beijing in this case, you would have to have something else entered in. here some earlier reports aid said that, no, no, the pilots entered waypoint, way off the course of beijing or their safety and they did that in advance, so that showed they had something nefarious in mind. but there was no evidence of that. there were just media reports and news reports coming out from various sources. and so what would happen is if you're communicating air traffic control ordinarily if you have an emergency, if something -- a rapid decompression in the plane, meaning your plane has burst is somewhere, literally like letting a leak out and you can't breathe, don't have oxygen, have to get your oxygen masks on, and also fit with the theory that another pilot had