American Airlines Mechanic Accused of Plane Sabotage May Have Ties to Terrorists, U.S. Says

Mr. Dunham asked for Mr. Alani to be released on $200,000 bail raised by relatives and American Airlines co-workers, but Judge McAliley said Mr. Alani was a flight risk and might be a danger to the community, according to The A.P.

On July 17, the day of the flight, Mr. Alani tampered with the air data module system on Flight 2834 from Miami to Nassau in the Bahamas, investigators said in court documents. The system, located in a compartment beneath the cockpit and near the nose landing gear, keeps track of an aircraft’s speed and pitch as well as other critical flight data.

As the Boeing 737-800 was approaching the departure runway and powering up its engines, the crew got an error message and aborted the takeoff, according to the documents.

Security camera footage showed that Mr. Alani had used a piece of foam to obstruct the module system, investigators said. They said it was unusual for Mr. Alani, who normally worked in a hangar for disabled aircraft, to be in the area of the plane.

A pitot tube, used to determine airspeed, a measurement vital to controlling the plane, was also loose, investigators said. Ice buildup in a pitot tube’s intake led to the 2009 crash of Air France Flight 447 over the Atlantic.

Two days after the July flight, American Airlines’ corporate security reported the suspected sabotage to the F.B.I., according to court records.

The TWU-IAM Association, which represents 30,000 of the airline’s employees in union negotiations, said in a statement on Sept. 6, the day after Mr. Alani’s arrest, that “any conduct that jeopardizes that safety is not tolerated or condoned by the leadership or members of our organizations.”