An airliner flew 150 miles past its destination because the two pilots were caught up in an argument with each other.
Controllers tried in vain to contact the Northwest Airlines crew to tell them they were approaching Minneapolis Airport, it emerged yesterday.
The Airbus, en route from San Diego with 144 passengers, passed over the city at 37,000ft on Wednesday.
Contact with controllers was not established until 14 minutes later, according to the National Transportation Safety Board, which is investigating the incident.
By that time, the plane was more than 100 miles away.
The pilots did not discover their mistake until an attendant in the cabin contacted them over the intercom.
They had lost communications with air traffic controllers for over an hour and flown 150 miles past Minneapolis before turning the plane round and landing safely.
The Federal Aviation Administration said the pilots, whose names have not been released, said they had become distracted by a conversation about airline policy and lost track of their location.
“It just doesn’t make any sense,” said Bill Voss, president of the Flight Safety Foundation in Alexandria, Virginia. “The pilots are saying they were involved in a heated conversation. Well, that was a very long conversation.”
Investigators were yesterday examining the plane’s cockpit voice recorder and flight data recorder.
Ben Berman, an airline pilot and former chief of major accident investigations at the safety board, said it becomes second nature for pilots to know when they need to begin landing preparations.
Investigators have not yet questioned the pilots and do not know whether it was possible they had fallen asleep.
They have both been suspended from flying while the airline holds an investigation.