What happened
On April 17, 2020, a Piper PA25-235, registration HK638, was performing an agricultural repositioning flight in Orocué, Casanare. After completing several spraying missions, the pilot intended to ferry the aircraft from the Minpro airstrip to the El Recreo airfield.
During the takeoff from runway 23, the aircraft initially climbed to approximately 300 feet AGL. While executing a steep left turn, the aircraft experienced a loss of airspeed and lift, leading to an aerodynamic stall. The aircraft subsequently lost altitude and impacted the terrain near Finca Providencia. The impact caused substantial structural damage to the aircraft, including the destruction of the left wing and the separation of the engine from the firewall. The two occupants were ejected from the aircraft upon impact; the pilot sustained minor injuries, while a ground assistant on board suffered serious injuries.
The investigation
The GRIAA investigation focused on the flight sequence, aircraft configuration, and operational oversight. Investigators examined the aircraft's weight and balance, noting that the center of gravity (CG) was outside of the permitted aft limit. The investigation also reviewed the presence of an unauthorized occupant and the takeoff environmental conditions, specifically noting a tailwind during the departure.
Findings
- The primary cause of the accident was loss of control in flight following an aerodynamic stall triggered by low airspeed during a steep turn, combined with power reduction and flap retraction during the initial climb.
- The aircraft was operated with a center of gravity exceeding the aft limit, a condition caused by the presence of an additional person in the cockpit.
- The aircraft was operated in violation of its design limitations, as it was carrying an extra occupant in a single-seat configuration.
- The takeoff was performed with a tailwind.
- The operator demonstrated deficient risk management regarding the planning and execution of the flight operations.
Safety action
- The operator was advised to update training manuals to strictly prohibit carrying more than one occupant in single-seat aircraft.
- Recommendations were made to strengthen operational policies regarding weight and balance calculations and aerodynamic principles, such as stall prevention and ground effect.
- The operator was encouraged to formalize a dedicated Safety Management Department within its organizational structure.