. >> bill vaz of the flight safety foundation and two test pilots joined us in an a330 simulator to recreatet happened in the final crucial moments. >> the auto pilot disconnects? >> yes. let's see how that looks. there's a warning. the aircraft is now in my control. i have to fly it manually. >> reporter: all of a sudden the computers are not in charge. cedric bonin, just 32 years old, is. at this point captain bonin makes his first mistake. he should have kept the plane flying. he shouldn't have changed anything, but instead he pulled the nose of the plane up. >> a dramatic pitch up. >> reporter: raising the nose is the wrong thing to do and can cause the airplane to fall out of the sky. it's the most baffling minute of the flight. the plane's stall warning goes off. >> stall, stall. >> reporter: but no one seems to pay any attention. >> stall, stall. >> it sounded for a total of 54 sng seconds, which is a long time. >> on the black box, bonin says i don't have control of the airplane at all. by now the other co-pilot is calling for the captain. where is he, he asks? is he coming? is he ke

. >> bill vaz joined us in i flight simulator to recreate what happened. >> what did he do? he fuld the nose up? >> a fairly dramatic up. >> it's precisely the wrong thing to do. it can cause the plane to start falling out of the sky. the stall warning goes off. >> it keeps saying, what's happening? they call for the captain six times. >> reporter: we don't know why it took him more than a minute to return to the cockpit, but two sources tell abc news that he was traveling socially with an off-duty air france flight attendant. were the two together? if the floot is distracted because he's traveling with somebody, potentially, isn't that part of the investigation? >> i don't think it could be an explanation of accident. >> reporter: in the cockpit, the captain finds a scene of utter confusion. what's happening, he asks? >> i don't know what's happening squrs one of the co-pilots. within seconds, the plane is plummeting, 120 miles an hour, nose up. though he still thinks his instruments are wrong. he asks, am i going down now? confusion turned into chaos with both pilots tryin