Delta Air Lines Flight 1080 was a scheduled flight notable for the incident that occurred on April 12, 1977 during the

San Diego San Diego ( , ; ) is a city on the Pacific Ocean coast of Southern California located immediately adjacent to the Mexico–United States border. With a 2020 population of 1,386,932, it is the List of United States cities by population, eigh ...

Los Angeles Los Angeles ( ; es, Los Ángeles, link=no , ), often referred to by its initials L.A., is the largest city in the state of California and the second most populous city in the United States after New York City, as well as one of the world' ...

leg of the flight. Unknown to the crew, the

Lockheed L-1011 The Lockheed L-1011 TriStar, also known as the L-1011 (pronounced "El-ten-eleven") and TriStar, is an American medium-to-long-range, wide-body trijet airliner built by the Lockheed Corporation. It was the third wide-body airliner to enter comme ...

's left

elevator An elevator or lift is a wire rope, cable-assisted, hydraulic cylinder-assisted, or roller-track assisted machine that vertically transports people or freight between floors, levels, or deck (building), decks of a building, watercraft, ...

had become stuck in a fully upwards position. This led to the aircraft pitching up aggressively and causing the aircraft to lose speed and nearly stall. The pitching force, unable to be overcome by fully pushing the control column down, was counteracted by reducing the thrust on the L-1011's wing engines but not the tail engine. The differential thrust, along with moving all the passengers as far forwards as possible in the cabin, pitched down the nose of the airliner and allowed the pilots to land the aircraft. An investigation found that the pressurization and depressurization of the L-1011 during flight cycles had caused water to be pushed inside a bearing, heavily corroding it and causing it to become jammed during a routine control surfaces check prior to takeoff. The FAA issued an emergency airworthiness directive instructing airlines to do a check of the bearing. This verification, however, was not sufficient to prevent takeoff with a jammed elevator; and a similar incident followed two months later. The FAA then made it mandatory for crews to inspect the elevators before each takeoff. As a result of the incidents, Lockheed redesigned the elevator systems to be redundant upon failure of the bearings, as well as adding a seal to the bearing and a deflector to reduce the amount of water contacting the part. Lockheed also modified the pilot's manual to improve the Pitch Axis Control Assist Procedures. The FAA further made it mandatory for pilots to be informed of these changes. For his skill in landing the crippled airplane, the captain, Jack McMahan, was awarded the FAA's Distinguished Service Award. The airplane was repaired and continued to fly for Delta until 1985. It was subsequently sold to American Trans Air, where it was registered with the tail number "N187AT". The airplane was scrapped in 2002.

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portrait of N707DA
the accident aircraft taking off Delta Air Lines accidents and incidents Accidents and incidents involving the Lockheed L-1011 Aviation accidents and incidents in California Aviation accidents and incidents in 1977 Aviation accidents and incidents in the United States in 1977 April 1977 events in the United States {{aviation-accident-stub

See also

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