Federal regulators are investigating how an American Airlines jet bound for Paris lost a panel from its belly shortly after taking off from Dallas-Fort Worth International Airport before continuing on across the Atlantic.
Part of the Federal Aviation Administration's probe centers on whether the pilot should have turned back, an FAA spokesman said.
Airline officials say the pilot thought the loud noises during the flight last month were due to cargo shifting, and in an internal memo they defended the crew.
A flight attendant on the April 20 trip said there was "a loud shaking noise from the belly of the plane." A few minutes later, there was another noise that "sounded like an explosion," the attendant said in an e-mail, according to Dallas television station WFAA.
When the Boeing 767 landed safely in Paris after the nine-hour flight, ground crews discovered a panel allowing access to an air conditioner was missing. The panel was part of the jet's outer skin and measured several square feet.
An American spokesman said the air conditioner area is separate from the cargo area and the pressurized cabin.
FAA spokesman Roland Herwig said the agency had launched an investigation. Asked whether that would include questioning the pilot's decision to keep flying, he replied, "Of course."
In a statement, the airline said it was also investigating the incident and wouldn't comment further. The company declined to identify the pilot. The pilots' union had no immediate comment.
Officials in the airline's flight department told pilots in a memo obtained by The Associated Press that the captain "did exactly what we want our captains to do."
"There was no way this crew could have known this panel had departed," said the memo from Jim Kaiser, American's manager of flight operations quality control, and Chuck Harman, the airline's fleet captain for Boeing 757 and 767 planes. "If they had known, they obviously would have returned" to DFW Airport.
According to the memo, no cockpit warning lights came on, and the pilot also spoke to a maintenance technician in Fort Worth.
Kaiser and Harman, who are both pilots, said while pictures of the hole in the fuselage "are very dramatic," the passengers were never in danger.
The incident on the Paris-bound flight occurred only a week after American canceled about 3,300 flights while it grounded its fleet of MD-80 jets to inspect electrical wiring.
