Electrical problems forced emergency landing at O'Hare

An emergency landing at O'Hare International Airport last month, when an American Airlines flight veered off a runway, was caused by electrical system "anomalies," according to a preliminary report by the National Transportation Safety Board.

None of the 185 passengers or seven crew members on Flight 268 from Seattle to New York on Sept. 22 were injured when the captain, with the end of the runway approaching and the brakes not able to "perform well," deliberately steered the Boeing 757 off the left side of runway 22R and into the grass, resulting in minor damage to the landing gear, the report said.

When en route, the plane developed an electrical problem, and used the standby battery power, which has a life of approximately 30 minutes. About one hour and 40 minutes later, "the battery power was depleted at which time several cockpit electrical systems began to fail," the report says. The plane was over Western Michigan when the captain requested to turn around and land at O'Hare.

Because the public address and interphone systems no longer worked, a flight attendant slipped a note under the cockpit door to inform the flight crew of the communication problems, the report says. Parts of the flight control system also failed to work properly.

"The touchdown was smooth despite the control issues," but the plane's "thrust reversers and spoilers did not deploy," the report said. Braking problems led the captain to intentionally veer off the runway and into the grass.

The incident remains under investigation until a final report is completed.