Accident Sequence
Flight 870, a scheduled domestic cargo flight from Bogotá-El Dorado International Airport to Barranquilla-Soledad Airport, took off from runway 30 at 0315 hours local time. Witnesses reported the aircraft appeared to lift off with difficulty opposite the control tower. After reaching the airport boundary, the crew announced their intention to return and land. The control tower queried the reason but received no reply. Tower personnel noted that during takeoff, engine noise was louder than usual, as if more than one engine was overspeeding. As the aircraft initiated a turn, a sudden flash was observed, and visual contact was lost. Shortly thereafter, the aircraft struck trees 400 meters from the "San Ramón" property, in a field belonging to the "Laguna Vieja" estate, between the roads leading to Funza and Engativá. The aircraft was destroyed by impact forces and a post-crash fire. Both pilots were killed.
Investigation Findings
The official investigation determined the probable cause to be a material failure: fatigue failure of a number of teeth of the pinion of the governor control unit. This caused the unit to jam against the rack in the "up" position, setting it for maximum rpm and resulting in engine overspeed. This was consistent with the dome ring being at maximum low pitch setting, indicating high rpm and a runaway propeller during takeoff.
A contributing factor was considered to be faulty supervision by the company. The company had briefed the pilot-in-command to conduct a night flight when he was not qualified for DC-4s, as he was still undergoing training for conversion to L-759 aircraft.