No one knows what set him off. But apparently on March 27th Pilot Captian Clayton F. Osbon lost his head completely. Although most of his ranting was incoherent, a lot of it appeared to be religious in nature. The flight was supposed to be traveling from New York to Las Vegas. However, Captain Osbon stated in the middle of the flight '"we're not going to vegas' because of its 'sins' and used the radio to admonish air traffic controllers to 'be quiet." - Source: NY Times National Issue 4/3/2012 issue, business section, p. B7. 

O_o 

You think that's nuts? ... heh! It's not over yet!

He blew his top when the frightened flight crew asked for a backup pilot to take over. Then, when the backup pilot took over and the crew locked Mr. Osbon out of the cockpit, he started screaming about "Jesus" "September 11" "bombs" "Israel" "Iran" and "Iraq." A flight attendant tried to calm him down... with no success. 

He shrieked at the passengers "EVERYBODY START SAYING THE LORD'S PRAYER!" and kept screaming that "They [its unclear who he was talking about] are going to take us down!" He was also kicking the locked cockpit door.

Eventually three male passengers wrestled the berserk captain to the ground and restrained him.  

Point: Religious nuts shouldn't fly planes - muslim nuts or christian nuts!

News Report on Crazy Pilot