WASHINGTON - Neither the pilots' conversations nor any background noises in the cockpit of American Airlines Flight 587 show any evidence that a terrorist attack or sabotage brought down the plane, the head of the National Transportation Safety Board said yesterday.

A complete transcript of the cockpit voice recorder, including background noises, showed no indication of a bomb or explosion, NTSB Chairwoman Marion Blakey said in an interview.

"You're seeing evidence that points in the direction of this having been an accident," Blakey said. "We continue not to have anything that points to terrorism. "

American Flight 587 plunged to the ground minutes after taking off from New York's Kennedy Airport on Nov. 12. The crash killed 265 people. Coming just two months after four commercial airplanes were hijacked, the crash initially raised fears of another terrorist attack.

Investigators are focusing on the tail of the Airbus A300-600, which sheared off before the crash. The plane hit turbulence from the Japan Air Lines 747 that took off before it, and the rudder showed sharp movements, but aviation experts say neither event should have been severe enough to break off the tail.

"Turbulence is significant," said John Clark, the NTSB's aviation safety director. "It's a player. But we don't see a huge vortex that just came along and knocked the tail off."

The Federal Aviation Administration has ordered inspections of the tail assembly of the French-built A300-600 and the A-310, which is made from the same nonmetallic composites. Blakey said no problems have been detected in any of the planes inspected so far.