What happened
On August 30, 2021, a Cessna TU206G, registration HK1833, was conducting an air ambulance mission between Puerto Inírida and Villavicencio, Colombia. The flight was transporting a patient and an accompanying person, along with a medical crew consisting of a pilot and a nurse.
While approaching runway 23 at Vanguardia Aerodrome (SKVV) at an altitude of 2,200 feet, the aircraft experienced a sudden loss of engine power, with RPM dropping to 1,400. The pilot attempted standard emergency procedures, including switching fuel tanks and adjusting mixture and fuel pump settings, but the engine failed to respond. Consequently, the pilot executed a controlled forced landing in an unprepared, muddy field approximately 4 nautical miles from the runway.
The impact caused substantial damage to the aircraft, specifically to the nose landing gear, the propeller blades, and the cargo pod. While the pilot sustained minor injuries, the other four occupants remained uninjured and evacuated the aircraft safely.
The investigation
The GRIAA investigation focused on the sudden engine failure and the maintenance history of the powerplant. Investigators examined the engine's ignition system, turbocharger, lubrication, and fuel systems.
During the inspection of the TSIO-520-M engine, investigators discovered that the fuel pump and fuel distributor currently installed did not match the components recorded during the engine's last overhaul. The investigation found a lack of traceability regarding the removal and installation of these specific components. While the aircraft's overall maintenance complied with manufacturer requirements and the aircraft was airworthy, the lack of documentation for these parts created significant uncertainty regarding their installation conditions.
Findings
- The primary cause of the incident was the forced landing in an unprepared field following a loss of engine power.
- The loss of power was likely caused by deficiencies within the engine's fuel system, specifically involving the fuel pump and fuel distributor.
- A critical lack of traceability existed for the installation of engine components, as the parts found during inspection did not align with the engine's overhaul records.
- The pilot effectively executed emergency procedures and managed a controlled descent, minimizing the severity of the impact.
Safety action
- The operator was advised to strengthen its Maintenance Quality Control procedures to ensure strict recording and updating of component control documentation, specifically guaranteeing traceability for the removal and installation of engine components.