Transcript for The Last Words of the Pilot and Co-Pilot on Malaysia Airlines Flight 370
ocean, we turn to the latest on the search of the lives of the pilots. Even the words of the co-pilot, when he said good night. ABC's chief justice correspondent, Pierre Thomas, spoke to the experts today. Reporter: Tonight, Malaysian authorities are urgently studying the captain's at-home flight simulator for clues. It was reassembled. Reporter: Investigators want to know, did the captain seen here on a widely circulated youtube clip, appearing to show him going through airport security, practiced the maneuvers that the flight made beforehand. And today, we learned from Malaysian officials, the critical importance of that last radio transmission from the plane to air traffic control. All right, good night, said someone in the cockpit could only four words be used to unlock the case. Do you believe the person who said all right, good night, from the cockpit, was the pilot or co-pilot? Initial investigation indicated it was the co-pilot. Who spoke the last time. What have you found? Have you analyzed it for stress? That is part of our investigation. Reporter: Investigators will look for any hint of a change in demeanor. Speaking too fast, voice goes up. Your voice box restricts when you're stressed out. Things of that nature. Reporter: A stressful voice could provide clues that the pilot was forced to act against his will. Or that he was planning something awful. Pierre Thomas, ABC news, Washington.
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