this story has turned into not how did the plane crash, but why. the prosecutor was very clear, sean. he said that the pilot had a reason for moving that button, the button that turns the plane into descent mode, landing mode if you will. he said it's not clear why he did that but we know the reason was ultimately to destroy the plane. now, we're trying to find out more about the co-pilot, andreas lubitz. there are contradictions in the stories that have been coming out so far that he loved his job. but a friend's mother says he took a rather long time-out in the midst of his training because he either burned out or some reports even say had a blackout. authorities have said he had no known links to terrorism. now, as far as investigators know and believe he killed 149 people, caused all their families immeasurable grief and has left hundreds of french mountain police with the painful task of collecting body parts and personal effects in fairly treacherous conditions all must