By Mike M. Ahlers
CNN
WASHINGTON (CNN) - A passenger flight from San Diego, California, to Minneapolis, Minnesota, overshot its destination airport by about 150 miles Wednesday, and federal investigators are looking into whether the pilots had become distracted, as they claimed, or perhaps fallen asleep.
[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2009/TRAVEL/10/23/airliner.fly.by/art.minneapolis.gi.jpg.jpg caption="An aerial view shows downtown Minneapolis."]
Air traffic controllers lost radio communication with the Northwest Airlines Airbus A320, carrying 147 passengers and an unknown number of crew, when it was flying at 37,000 feet, according to the National Transportation Safety Board. There was no communication with Flight 188 for more than an hour as it approached the airport, the board said.
When air traffic controllers finally made contact with the pilot, his answers were so vague that controllers feared the plane might have been hijacked, according to a source familiar with the incident.
The controllers in Minneapolis ordered the pilot to make a series of unnecessary maneuvers to convince them the pilots were in control of the flight, the source said, adding that fighter jets were poised in Madison, Wisconsin, but were never deployed.