Avianca Flight 870

Avianca Flight 870 (flight number: AV870, callsign: AVIANCA 870) was a scheduled cargo flight operated by Avianca from Bogotá Airport to Barranquilla Airport. On this flight, on 22 September 1966, the Douglas DC-4-1009 aircraft being used had to turn back to the departure airport shortly after takeoff due to engine problems, but in doing so collided with trees and crashed. Both pilots on board were killed in the accident.

Accident sequence

The DC-4 was to operate a nighttime scheduled cargo flight from Bogotá to Barranquilla. The pilots received clearance to take off from runway 30. The aircraft lifted off at 3:15. Eyewitnesses reported that the aircraft gained altitude only with difficulty after takeoff. As the aircraft approached the outer boundary of the airport grounds, the pilots requested clearance to return for an emergency landing. The air traffic controller received no answer to the question of why the pilots wanted to turn back. The air traffic controllers later stated on record that the engine noise of the aircraft after takeoff had been louder than usual. From this they concluded that more than one engine of the aircraft must have oversped. While the aircraft was flying a turn to return to the departure airport, the air traffic controllers had noticed a sudden flash of light and then lost visual contact with the aircraft. Shortly afterwards, the aircraft had clipped some trees and then crashed into a field that lay between the connecting roads to Funza and Engativá. The aircraft was completely destroyed by the impact and the fire that broke out immediately afterwards. Both pilots were killed.

Accident investigation

During the inspection of the accident site, it was found that the aircraft had first struck a tree with such force that it had been almost uprooted. The wreckage was scattered about 150 metres around the location of the main wreckage. The accident was assessed as not survivable.

The cause of the accident was determined to be a fatigue-related material failure of several pinions of the torque regulator on engine No. 2, which then oversped. The pilots were unable to control the engine power or to feather the propeller. Almost simultaneously, engine No. 1 failed as a result of a suddenly erupting engine fire. Since the aircraft was loaded up to the limit of the maximum takeoff weight, it was not possible to maintain altitude using the remaining engine power, so that the loss of altitude and the crash were unavoidable.

The airline was blamed for having used on the flight an inadequately trained captain who was not licensed at all for night flights on the Douglas DC-4.