U.S. airlines completing inspections of Airbus A300s

Focus is on planes' tails after crash of jet in N.Y.

November 22, 2001|By COX NEWS SERVICE

ATLANTA - U.S. airlines flying Airbus A300s are finishing inspections of the planes' tails after the deadly Nov. 12 crash of American Airlines Flight 587 in New York, but some aerospace experts say those inspections might be too superficial to reveal hidden damage.

"Surface inspections are incomplete at best," said Ronald M. Barrett, an aerospace engineer at Auburn University who specializes in composite materials. "To detect internal damage, you need more than a simple surface inspection."

Parts torn from plane

The 27-foot tail fin, known as a horizontal stabilizer, and rudder were apparently torn from the plane after it twice encountered choppy air behind a much heavier Japan Airlines Boeing 747-400.

The Airbus crashed in a residential Queens neighborhood 18 seconds after the second bout of turbulence, killing all 260 people aboard and five on the ground.

Like many modern airliners, the A300's horizontal stabilizer and rudder were made from composites.

FAA deadline of Dec. 2

The Federal Aviation Administration's directive gave U.S. A300 operators until Dec. 2 to visually inspect tails and five more days to report findings.

"It may be possible to detect indications of possible failure modes that could result in separation of the vertical stabilizer from the airplane," the FAA said in the order covering more than 90 U.S.-registered A300s.

The agency said those indications could range from cracked paint to surface distortions.

"No one has seen any significant problems with the visual inspections," FAA spokesman Les Dorr said.

But Barrett said more advanced tests such as X-rays, ultrasounds and infrared imaging are required. And even those tests aren't foolproof.

"There's a certain amount of interpretation in analyzing the results," Barrett said.

Michael Hunt, an aerospace engineer and composite material expert in Savannah, Ga., said composites are lighter, stronger and more durable than metal. But the material gives few if any indications of problems before failure.

"It's an all-or-nothing material," he said. "Metal usually cracks or discolors before it breaks. Composites don't."

According to published reports, the National Transportation Safety Board also is exploring how American Airlines pilots are trained to use rudder controls to recover from "upsets" such as those that could result from severe wake turbulence.

The plane's flight data recorder showed the rudder swung several times, left and right, before the accident.

The swings corresponded to rudder pedal movements in the cockpit, investigators said.

United Parcel Service said it expects to finish inspecting its 18 A300s by the end of the week.

"We haven't found any problems so far," said Travis Spalding, a UPS spokesman.

Ed Coleman, a spokesman for FedEx, the largest operator of the U.S. A300, said the Memphis-based company is in the process of inspecting its 37 aircraft.

"Inspections are continuing," he said. "We're communicating closely with the FAA."

American is the only U.S. passenger carrier that flies A300s, and it has 34. More than 400 of the planes are flying worldwide.

The same jet involved in last week's crash flew through severe turbulence in 1994 that injured 47 people.

But the plane soon returned to service, and it underwent a regularly scheduled major mechanical overhaul in 1999.

The plane also had a problem with one of six fasteners in the vertical tail when it was built, but the composite part was repaired in 1988.

Dorr said visual inspections were a prudent first step.

"We're not ruling out any additional safety actions," he said. "We wanted to get a feel for the state of the materials in the fleet."

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