An Alaska Airlines MD-80 was forced to turn around and make an emergency landing in Seattle this morning after the pilot reported problems with the plane's horizontal stabilizer in flight.
A separate problem delayed a Juneau flight for at least five hours today.
Alaska Flight 288 took off at 8:02 a.m. from Seattle-Tacoma International Airport, heading for Los Angeles with 51 people on board. Shortly after takeoff, the pilot reported a problem with the plane's trim, the adjustments in flight direction made by the horizontal stabilizer and vertical fin on the aircraft's tail, airport spokesman Bob Parker said.
Alaska spokesman Jack Evans said the fault was in the stabilizer's motor, which turns a jackscrew that causes the wings on the tail to move. A secondary jackscrew motor functioned correctly, Evans said.
Failure of both motors could freeze the stabilizer in place, though Evans said a pilot could still land safely if that were the case.
The plane made a successful landing at Sea-Tac shortly before 9 a.m. There were no injuries reported, Parker said.
A failure in the horizontal stabilizer's jackscrew has been implicated in the Jan. 31 crash of an Alaska MD-80 off the California coast, which killed 88 people. In that case, the jackscrew itself was found to be stripped -- a far worse situation than a stabilizer that is simply frozen.
On Aug. 3, Alaska pulled 17 of its MD-80 aircraft out of service to check the horizontal stabilizer mechanisms after it was discovered that an Alaska-made tool that measures stress on the jackscrew could give inaccurate readings if improperly used. No problems were found and the planes were returned to service.
Evans did not know whether the MD-80 that made the emergency landing Thursday was one of those inspected last week, but said that the motor problem was unrelated to the inspections.
The Juneau incident involved Flight 176, which could not leave the Juneau Airport at 6 a.m. today because of technical difficulties with its fire suppression equipment, Evans said.
About 130 passengers were stranded in Juneau.
``They got an indicator light in the cockpit that showed the equipment wasn't functioning properly,'' Evans said.
``It's a lot more complicated than a home fire alarm. It's connected to everything, and, until it's fixed, they don't know how long it will take to fix it,'' he said. Parts were being flown in.
``They are still trouble-shooting,'' confirmed airport manager Allan Heese shortly after 11 a.m. today. ``There are a few people sitting around, but everybody seems calm.''
Alaska Airlines flights out of Juneau in August are typically full, and once a plane stacks up here, ``It affects many, many people all over our system,'' Evans said.