Report: Jet May Have Broken Apart

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Report: Jet May Have Broken Apart

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Updated 7:18 AM ET February 8, 2000

By MATTHEW FORDAHL, AP Science Writer

LOS ANGELES (AP) - Radar data shows a piece of Alaska Airlines Flight 261 may have broken off seconds before the plane plunged into the Pacific Ocean, according to published reports.

The Los Angeles Times and The Washington Post, both citing anonymous sources, reported today that the object - without the markings of an aircraft - appeared to be buffeted by winds as it fell, indicating that it could be part of an aerodynamic surface such as a wing or tail.

But the papers said it was too early to say what exactly the image depicts or whether it could have been part of the stabilizer, the section of the plane the crew indicated was malfunctioning.

National Transportation Safety Board investigators have not determined the cause of the crash but are focusing on the stabilizer.

Meanwhile, concern over the safety of MD-80-series aircraft like the Alaska Airlines MD-83 that crashed Jan. 31 may be leading pilots to become overly cautious about testing their planes' rear stabilizers.

In the week since the crash that killed 88 people, three U.S. jetliners have returned to their gates because of stabilizer problems. Airline officials said Monday at least two of the incidents probably can be traced to pilots inadvertently overheating the motors by repeatedly testing the equipment.

"It may be that some pilots are being overly cautious and are running through their checks several more times than they typically do," said Jack Evans, an Alaska Airlines spokesman.

The horizontal stabilizer is a moveable, 40-foot wing mounted high on the aircraft's tail. It guides the up-and-down motion of the plane during flight, and is controlled by two motors that turn a jackscrew, similar to the mechanism that controls garage door openers.

During a flight, the motors force more than 100 adjustments, slightly changing the pitch as the airliner uses fuel and as other conditions shift.

On the ground, the motors can last up to 90 seconds before overheating and shutting down. It is usually not a problem in flight because of the cold temperatures in the atmosphere.

After shutting down, the motors should become operative again after cooling down for several minutes, said John Thom, spokesman for Boeing, which bought McDonnell Douglas, maker of the MD-80 series planes, in 1997.

"We are getting the word out there (to pilots) to make sure you give enough time for these motors to cool down if you do go through the check again," Evans said.

Another, apparently unrelated, incident involving an Alaska Airlines jetliner occurred Monday night when an MD-80 made an emergency landing at San Francisco International Airport moments after takeoff after sparks were seen flying from an engine.

It was not clear early today what caused the problems with the plane that had come from Puerto Vallarta, Mexico, stopped in San Francisco, then headed on to Seattle - the same flight path as Flight 261.

No injuries were reported in the incident, and passengers traveling to Seattle were put on another plane.

On Saturday, an Alaska Airlines MD-83 jet returned to the airport in Reno, Nev., minutes after taking off for Seattle. The NTSB is investigating, but the airline said it was probably caused by an overheated stabilizer motor.

On Thursday, an Alaska MD-80 taxiing toward the runway in Seattle experienced "intermittent problems" with the stabilizer motor. After returning to the gate, the parts were swapped out and the plane took off without incident.

An American Airlines MD-83 flight out of Phoenix returned to the gate last week with a stabilizer problem, but investigators said it may have been caused by a faulty control switch in the cockpit.

"There's usually an increase in reports of concerns by pilots about similar conditions after an accident," said Mitch Barker, an FAA spokesman in Seattle. "It just raises the visibility and everyone's sensitivity to the possibility."

Added Steve Roach, a pilot union official who flew MD-80s for three years: "You don't change your procedures, but guys tend to focus a little bit more on the systems involved."

Pete Harkovitch, who was a passenger on the jet that had to return to Reno, said he will avoid MD-80s until investigators figure out what happened to Flight 261.

"I was terrified," said the 42-year-old Fairbanks, Alaska, resident, who flies two to three times a month. "It was too close to the other accident that killed so many innocent people. If MD-80s look like they're trouble-free, then I'll go back on them, but if I had to fly tomorrow, I'd take something else."

-- Gerry Rivers (grivers@caponi.123), February 08, 2000


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