American Airlines Flight 625

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American Airlines Flight 625, a Boeing 727, crashed at St. Thomas, U.S. Virgin Islands on April 27, 1976.

The American Airlines Boeing 727 (Registration N1963), overran the departure end of Runway 9 when landing at the Harry S Truman airport. The aircraft struck an Instrument Landing System antenna, crashed through a chain link fence and travelled another 1,040 until stopped by a building, the aircraft was destroyed.

The airport at St. Thomas was notorious among pilots for its short (4,658 feet) runway. In fact the Boeing 727 was the heaviest aircraft type authorized to use it, and even then it was only authorized in one direction.

Ultimately, the NTSB attributed this crash to pilot error on the approach – for example the maximum flap setting of 40 degrees was never applied – meant that the aircraft's speed was 10 knots higher than Vref as it crossed the runway threshold. This combined with the fact that the aircraft 'floated' from the turbulent winds in the area meant that it was already 2,300 feet down the runway at the point of touchdown. The pilots were not fast to act on the brakes and then went full-throttle three seconds after touchdown, but were unable to reach take-off speed because the 727's engines are slow-responding, taking about 6.6 seconds to power up. After five seconds of waiting for power, and with only 700 feet of runway left, the pilot panicked, according to the report, and applied full brakes. However, he forgot to point the nose of the plane down, which would have significantly slowed the aircraft. Further, the pilot forgot to apply reverse engine thrust until immediately before impact. Ultimately, the aircraft ran off the end of the runway and into a Shell gas station, killing 37 (35 passengers and two flight attendants) of the 88 on board. Thirty-eight other passengers and crew were injured and one person on the ground was seriously injured. The probable cause was the captain's actions and his judgement in not being aware that when he touched down 2,300 feet into the 4,658-foot runway, he did not have enought distance to perform a go-around.

As a result of the crash, American Airlines ended all jet flights to St. Thomas, flying instead to St. Croix (where the runway is much longer) from which passengers could fly to St. Thomas using propeller-driven aircraft. Jet flights resumed when the runway was lengthened to 7,000 feet.