NTSB scrutinizing Airbus mechanical problem

From Kathleen Koch
CNN Washington Bureau

WASHINGTON (CNN) -- Federal officials are looking into whether a mechanical problem discovered last week on a Federal Express Airbus A300 provides clues to the cause of the crash last November of an American Airlines Airbus A300 in New York.

National Transportation Safety Board spokesman Ted Lopatkiewicz said that during a routine maintenance check Friday at a Federal Express facility in Memphis, Tennessee, mechanics found the aircraft had a bent actuator rod. The rod is the part that moves the rudder.

Sources from the FAA and another government agency said they were looking for a possible link between the bent rod and the crash of American Airlines Flight 587 soon after takeoff November 12 from John F. Kennedy International Airport into a neighborhood in Rockaway, Queens.

The plane's tail and rudder, which were fished out of Jamaica Bay, have been scrutinized as possibly contributing to or causing the crash, which killed all 260 people on the plane and five people on the ground. The NTSB is still investigating its cause.

A team of NTSB and FAA investigators was heading to Memphis to examine the FedEx plane. Federal Express' fleet has 37 Airbus A300s, all five to seven years old.

One source involved in the investigation called the problem "very interesting," and Lopatkiewicz said a bent actuator rod is "unusual."

The NTSB expects to complete a report on the FedEx aircraft in the next few days.

Airbus spokesman David Venz said he was aware NTSB was investigating the problem, and a FedEx spokesman said Airbus has posted a full-time representative at the FedEx facility to supervise maintenance technicians.

Aviation analyst Jim McKenna said investigators would be interested in any unusual problem that cropped up with the rudder or hydraulic system but cautioned it was "too early to tell if this is a critical turn in the investigation."

FedEx says its mechanics completed FAA-mandated checks of the tail fin and rudders on its fleet of Airbus planes in November following the crash of Flight 587 and found nothing unusual.

Meanwhile, two A300 Airbus planes that were pulled off Caribbean and South American flight routes by American Airlines after the pilots reported tail control problems have been returned to regular service.

An airline spokesman said vibration was caused by engine surging and not the rudder.

Both times, crews reported "tail wag," where the back end of the plane moves from side to side, an American Airlines spokesman said.

The first incident of what the crew felt were control problems occurred January 17 as the Airbus was departing Miami for Caracas, Venezuela. The pilot returned to Miami.

When the same plane was used on its next flight to Caracas two days later, that crew also reported "tail wag," the spokesman said.

The Airbus was taken to an American Airlines' maintenance facility in Tulsa, Oklahoma, for testing.

When mechanics diagnosed the problem as engine vibration and changed the engine, the problem cleared up, the spokesman said. The Airbus will be returned to passenger service Tuesday, he said.

The second plane that had reports of tail wag took off January 25 from San Juan, Puerto Rico, to New York. Mechanics changed that engine, too. That Airbus resumed flying passengers over the weekend.

The first report of pilot problems with an Airbus after the crash came November 28, when the crew felt sideways movements after takeoff from Lima, Peru. The pilot returned the plane to Lima.

Investigators removed the yaw damper actuator from the Lima and the Caracas planes and sent them to an outside lab for testing, an NTSB official said.

The yaw damper is a computerized device intended to smooth out minor deflections in flight by controlling the plane's rudder.

The NTSB has said the yaw damper on the doomed American 587 flight in New York had to be re-set before the crew could push back from the gate the morning it crashed.

Pilots say there is normally no reason to expect failure of the yaw damper to imperil a flight.

However, an American Airlines Airbus preparing to land in Miami after a flight from Bogota, Colombia, on May 11, 1999, experienced control problems that were traced to the yaw damper.

An FAA report said that when the plane aborted the landing and flew over the airport, "the yaw deviations increased and became extreme." The plane landed safely.

The NTSB has said two wires in the yaw damper had been inadvertently reversed. The FAA issued a directive which appears to have corrected the problem.

-- CNN Producers Beth Lewandowski and Jim Polk contributed to this story.