Washington (CNN) -- The Northwest Airlines pilot who overflew his destination in October -- and now is fighting to regain his pilot's license -- was contrite and apologetic soon after the incident, documents released Wednesday show.
"There's no good excuse," Capt. Timothy B. Cheney told National Transportation Safety Board investigators four days after the event. "I let my guard down," he said. "I wish I could explain why."
Cheney, 53, and First Officer Richard I. Cole told investigators they had not fallen asleep, as originally had been suspected, but rather had become distracted by an airline scheduling system on their laptop computers and "got deeper and deeper into it."
When a flight attendant called the cockpit to ask when they would land, the pilots realized that not only were they a half-hour late for the scheduled prelanding deceleration, they also were about 150 miles beyond the Minneapolis, Minnesota, airport where they were supposed to land.
Cheney, an experienced pilot with about 20,000 hours of flying time, told investigators he was "blown away" that he had been distracted for so long, saying that in 24 years of flying, "I've never, ever, been in this situation."
He acknowledged putting his 144 passengers "at risk," and said he was embarrassed, the safety board report says. "You'll never know how sorry I am," it quotes him as saying.
The crew of Northwest Flight 188 was out of radio contact with radio controllers for 77 minutes during the October 21 flight from San Diego, California, according to the Federal Aviation Administration. During that time, air traffic controllers and the airline's dispatchers made numerous efforts to contact the plane by radio and through text messaging devices.
When the flight attendant called him, Cheney said, he looked at an onboard display and saw no flight plan, then looked at a navigation display and and saw Duluth, Minnesota, to the left and Eau Claire, Wisconsin, ahead to the right.
After Cole contacted controllers, Cheney told passengers the airport was "taking arrivals from the east; we should be on the ground 25-28 minutes," but did not explain the situation.
Cheney told Cole: "They'll find out on the ground."
The report gives new details of the incident, but also raises new questions, including ones about the pilots' actions in the wake of their mistake.
First Officer Cole told the safety board that after the pilots discovered their error, he noticed several messages on a display instructing the crew to "contact ATC [Air Traffic Control]." Cole said he then "inadvertently" pushed the "delete all" button, erasing all the dispatch messages.
Neither pilot could remember what happened to the cockpit paperwork, the report says. "Both stated they believed the Northwest chief pilot who met the aircraft may have taken possession of it," it says.
But in a separate document, Northwest Chief Pilot Todd Luebke said he saw no signs of the paperwork.
"I don't know if the crew retained them or due to their distraught state discarded them as we normally do on domestic, uneventful flights," Luebke wrote.
Uninvolved pilots contacted by CNN said the cockpit paperwork typically consists of dispatching orders, aircraft and cargo weights, passenger counts and other information that likely would not be relevant in an investigation of this sort.
But the safety board report suggests the paperwork could have given clues as to whether the first officer had completed certain tasks, including a fuel calculation routinely performed after take-off.
The report dashed hopes that the cockpit voice recorder would shed light on the event.
The voice recorder contains about one minute of audio recorded while the plane was in the air, the safety board said. The rest of the half-hour recording was taped over while the plane sat on the ground.
Luebke said he could not enter the cockpit and pull the recorder's power until law enforcement officials in the cockpit had finished interviewing the pilots about the incident.
"In retrospect, a delay in having contact with the crew plays a large role in how we perform our duties," his statement reads, saying the delay prevented him from killing the voice recorder's power "in a timely fashion."
Six days after the flight, the Federal Aviation Agency revoked Cheney's and Cole's pilot's licenses. Both have appealed the revocation to the National Transportation Safety Board.
The FAA said the pilots' lack of awareness that they had overflown the Minneapolis airport was "completely unacceptable" and "put your passengers and your crew in serious jeopardy."
The safety board report says both pilots passed a field breathalyzer test, and later that day passed drug and alcohol tests administered by their company.
One airline pilot contacted by CNN said the event has shaken veteran pilots, who fear they may be capable of similar mistakes.
But, he said, "It's one thing to be distracted for three minutes. It's another thing to be distracted for so long that you overfly your destination. I'm having a hard time with that."