What happened
On September 30, 2016, a Cessna 2/08B, registration HK3804, operated by Llanera de Aviación S.A., was performing a scheduled air taxi flight from Olaya Herrera Airport (SKMD) to Juradó (SKJU). The aircraft was carrying two crew members and nine passengers, including an infant.
Shortly after departing at 11:58 HL, the aircraft began a climb following a prescribed route toward Cerro El Volador. Approximately six minutes into the flight, the aircraft experienced a loss of altitude. Unable to maintain its climb, the pilot attempted an emergency landing in the mountainous region of Vereda El Barcino, near San Antonio de Prado. The impact destroyed the aircraft. The accident resulted in four fatalities, including the co-pilot and an infant, and seven serious injuries among the remaining occupants.
The investigation
The GRIAA investigation examined several hypotheses to explain the loss of performance, including engine failure, propeller malfunction, or aerodynamic loss of lift due to weight. While the engine and propeller were found to be functional upon inspection, the investigation was reopened later to analyze a propeller spinner recovered from the site and new fuel procurement documentation.
Investigators identified significant discrepancies in the aircraft's weight and balance records. The crew used an incorrect empty weight for their calculations, underestimating the actual basic empty weight by 157 lbs. Furthermore, the crew failed to account for the weight of the cargo on board. The investigation also noted inconsistencies in fuel logging from previous flights and a lack of oversight regarding passenger and cargo reporting by the operator.
Findings
- The aircraft was operating near its maximum takeoff weight.
- Inaccurate weight and balance calculations were performed by the crew, specifically regarding the aircraft's empty weight and the weight of the cargo.
- The pilot failed to properly review the weight and balance manifest prepared by the co-pilot.
- The operator lacked sufficient oversight to ensure that passenger and cargo counts were accurately reported to the main base.
- Environmental factors, including high temperature (27ºC) and a tailwind, necessitated precise performance planning that was not fully executed.
- The investigation could not definitively confirm a mechanical cause, leaving the ultimate cause of the loss of climb capability as indeterminate.