error. in fact, a ten-year study by boeing shows nearly two-third of aircraft losses are due to human factors. even without the wreckage, investigators should be interviewing everyone who touched that plane. those who loaded food. pilots who flew this jet on earlier flight. maintenance records. cargo handlers. in fact, it was improperly stored cargo that led to a fire which brought down a value jet in the florida everglades. >> so we need to keep an open mind. continue the search, find the wreckage, find those black boxes and begin to solve this mystery. >> reporter: those two black boxes, which record the pilot's voices and data from the plane can be critical. after nearly two years, those black boxes from air france 244 were recovered from the bottom of the atlantic by a mini sub. they show a sensor malfunction followed by pilot error led to the deadly crash. the boxes will tell us what happened, but sometimes not why. that was the what happens with the crash off long island. it was an explosion.