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Tail fin to be removed for crash clues
By BILL ADAIR, Times Staff Writer WASHINGTON -- Airbus and American Airlines plan to remove the tail fin from an A300 jetliner involved in a dramatic 1997 incident over West Palm Beach to look for clues about last November's crash of American Flight 587 in New York. National Transportation Safety Board investigators recently discovered that the pilots in the incident five years ago made alternating rudder movements that put strong air loads on the tail fin. They want to examine the fin to see if it has damage that was not detected by inspections after the incident. Alternating rudder movements have been a major focus of the investigation of Flight 587. The A300 crashed in Rockaway Beach, N.Y., killing 265, after its tail fin snapped off. The NTSB has said the rudder moved in both directions just before the tail broke, but investigators have not determined whether the movements were caused by the pilots or a malfunction. Two weeks ago, the safety board asked the Federal Aviation Administration to warn airline pilots that alternating rudder movements can put strong loads on a fin that could make it break off. This week, Airbus and American employees plan to remove the fin, which is made from a composite material called carbon fiber reinforced plastic. They will use a newly developed ultrasound inspection to see if the 1997 incident caused any interior damage. Airbus spokesman Clay McConnell said the fin was inspected after the May 1997 incident and no problems were found. He said the inspection will provide "an added measure of safety and a means of validating the measures already taken." Airbus expects that no problems will be found, McConnell said. Because American Airlines does not have any mechanics who are skilled at removing a tail fin -- the 27-foot structure is usually not removed from the fuselage -- Airbus is sending a team of engineers from its headquarters in Toulouse, France. NTSB investigators will take part in the examination to look for any evidence that might help them explain what happened to Flight 587. The removal and testing of the fin is unusual and will keep the plane out of service for as much as two weeks. American, which has 34 A300s, said there should be no schedule disruption from the tests. By coincidence, the plane -- known as "070" -- last week was in an American hangar in Tulsa, Okla., when the decision was made to remove its tail. The plane was undergoing another examination, prompted by the November crash, in which mechanics removed and inspected a bolt that held the tail to the fuselage. No problems were found. American spokesman John Hotard said NTSB investigators "requested the special test because the amount of stress on the tail was similar to that which 587 is believed to have experienced." The test will be done in Tulsa later this week. But Hotard said that American "has no reason to believe that 070 was damaged." When the NTSB investigated the West Palm Beach incident in 1997, the board concluded that the pilots stalled the plane and nearly lost control as they tried to recover. But in the past few weeks, as investigators took a closer look at the flight data, they discovered the pilots made strong alternating rudder movements. The rudder is the moveable vertical panel on the tail fin. Pilots of big jets primarily use it when landing in a strong crosswind or if they have an engine failure. Occasionally, they also use it to level the wings after the plane has suddenly rolled to one side. In the 1997 incident, the American Airlines flight from Boston to Miami was at 16,000 feet near West Palm Beach when the pilot reduced power to descend to land, according to an NTSB report. The plane was slowed so much that it began to stall, a condition when there is not enough air crossing the wings to keep the plane aloft. In the cockpit, the pilot felt the stickshaker, which loudly rattles the controls to warn that the plane is about to stall. The pilot then took a rapid series of actions to regain control of the plane, turning the wheel and pushing on the left and right rudder pedals. The aircraft gyrated for about 34 seconds, injuring a flight attendant and a passenger. The pilot finally recovered control at about 13,000 feet, told air traffic controllers he was declaring an emergency and landed in Miami. The NTSB blamed the pilots, saying they failed to maintain sufficient airspeed and failed to use proper stall recovery techniques. The plane, an A300 that was slightly newer than the plane involved in the 587 crash, was inspected shortly after the incident and no tail fin problems were found. And no problems have been reported since then, Airbus and American said Monday. American uses the A300 on longer routes such as New York to the Caribbean.
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