What happened
On March 9, 2019, a Douglas DC-3, registration HK2494, was performing a non-scheduled passenger flight from San José del Guaviare to Villavicencio. During the cruise phase at approximately 8,500 feet, the aircraft experienced a failure of the number one engine.
Following the engine failure, the propeller on the left engine failed to feather, remaining in a high-pitch position. This created significant drag and prevented the crew from maintaining the minimum controllable airspeed (Vmca). As the aircraft lost altitude, the pilot attempted to locate a nearby landing site and decided to perform an emergency landing at the La Rinconada airstrip. During the approach, the aircraft lost further altitude and collided with the terrain approximately 0.35 NM from the runway. The impact resulted in a post-crash fire that destroyed 85% of the aircraft. All 14 occupants (three crew members and 11 passengers) sustained fatal injuries.
The investigation
The GRIAA investigation focused on the mechanical failure of the engine and the propeller feathering system. Investigators examined the lubrication system of the number one engine, noting an abundant oil leak during flight. The investigation also reviewed maintenance records, finding discrepancies regarding the pressure line for the propeller feathering system and a lack of documentation for the most recent 50-hour Phase A service.
Furthermore, the investigators analyzed the operator's safety management systems, noting the absence of an approved SMS and a lack of real-time flight tracking capabilities. Radar data confirmed that while the aircraft's speed remained relatively constant at an average of 85 knots, the altitude decreased continuously until the moment of impact.