Accident Sequence
On the day of the accident, a personnel transfer flight was departing from Formosa-El Picú Airport at approximately 1550 local time. The aircraft carried four passengers and three crew members. Witnesses observed the aircraft accelerate along the runway for about 800 meters, but it only gained slight altitude a few meters before the runway end. It then struck a runway end marker, the perimeter wire fence, and a telephone pole. The aircraft contacted the ground twice before demolishing another wire fence and coming to rest against a small hill. A fire erupted upon impact.
Casualties
Six of the seven occupants were killed instantaneously. The copilot, Captain Alberto Manuel González, suffered serious injuries and died several months later from burns sustained in the accident.
Aircraft and Operator
The aircraft was owned and operated by the Dirección Nacional de Aviación Civil (DINACIA).
Official Findings
The investigation determined the probable cause to be the aircraft's inability to reach takeoff speed after an 800-meter ground run. This resulted from:
- Insufficient driving power for the operation, attributed to a reduction in power in one or both engines due to premature ignition and detonation caused by the use of spark plugs inappropriate for the engine type.
- A probable reduction in engine revolutions per minute during the takeoff run, following unnoticed slipping of the propeller controls.
- The aircraft being overloaded relative to its maximum authorized takeoff weight.
- Contributing to the accident were the weather conditions in relation to the characteristics of the runway, as indicated by the circumstances of the operation.