Updated Thursday, December 6, 2012 at 06:50 AM
Investigators looking into why a United Airlines 787 jet made an emergency landing Tuesday found that one of the plane’s six electrical generators failed, Boeing said Wednesday.
The failure likely caused the multiple system-error messages in the cockpit that prompted the pilot to declare an emergency and land in New Orleans.
But Boeing spokeswoman Lori Gunter said “the multiple redundancies built into the 787 ensured that the airplane remained powered.”
The generator that failed was one of four used to start the engines and also to provide electrical power to different airplane systems in flight. Each generator provides about 250 kilowatts of power.
The other two generators are primarily for use on the ground, but can be backup power sources in flight.
United Flight 1146, which took off from Houston en route to Newark, N.J., landed safely with 174 passengers and 10 crew members aboard.
Coming into New Orleans the pilot told air traffic controllers that the plane had “an electrical malfunction” and asked that the firefighters lined up for the emergency landing take a close look at the electronics bay behind the wing.
In 2010, an electrical short on a 787 test flight caused a serious fire in the electronics bay. However, inspection of the United plane’s electronics bay after landing revealed no signs of arcing and no fire.
The airplane, the latest of three Dreamliners United is flying, was delivered to the airline Nov. 20.
It remains on the ground in New Orleans as United and Boeing engineering teams continue to troubleshoot the incident.
United last month became the first U.S. airline to fly the Dreamliner.
Gunter said the generator will be replaced, additional checks completed and the airplane returned to service.
“There is no firm estimate for when this is expected to be complete but it should not take long,” she said in an email.
Dominic Gates: (206) 464-2963 or email@example.com