theory of the lithium batteries or a mechanical failure, the pilot would have been turning and and going to subang near kuala lumpur. that's their maintenance base. if the severity of the event, if he underestimated the severity of the event, geez, we're not going to make it where we're headed to beijing, let's turn around and go back to the mate nance base. they're not going to go back to kuala lumpur if they're not thinking it's a severe emergency. >> would that not have necessitated a mayday call or would that not be the sort of thing that rises to a mayday call? >> it definitely would have been. whenever you're going off course like that it does -- it would also the acar system would have sent an emergency message, something is happening here, throttles are back, diving down to 12,000 feet. when they made the turn the acar system was already disabled. >> the person of bad intention would have wanted to turn off a transponder but there would be