What happened
On March 6, 2021, a Petrel 912i aircraft, registration LV-ITP, was conducting a recreational flight near Timbúes, Santa Fe, when the engine experienced a significant drop in revolutions per minute (RPM). The engine power decreased to approximately 1,200 RPM while the aircraft was at an altitude of 1,000 feet.
The pilot attempted several corrective measures, including an engine restart attempt and switching fuel tanks, but the engine failure persisted. Consequently, the pilot performed an emergency landing in a field containing soybean residue. There were no injuries to the two occupants and no damage to the aircraft.
The investigation
The investigation examined the aircraft's fuel system and the flight conditions leading up to the event. Post-incident inspections of the engine revealed no mechanical defects. Investigators verified that the fuel filter was clear of particles and confirmed that fuel flowed via gravity from the lines. Subsequent engine tests showed normal operation.
Data regarding fuel levels at the start of the flight indicated an asymmetrical distribution: approximately 15 liters were in the left tank and 5 liters in the right tank. Following the emergency landing, the left tank showed 13 liters remaining, while the right tank provided no readable indication of fuel level.
Findings
- The engine failure was likely caused by fuel starvation.
- The asymmetrical fuel load required careful monitoring of the fuel selector valve.
- The lack of a readable fuel level in the right tank contributed to the inability to monitor the fuel depletion in that specific tank.
- While the maintenance manual suggests running the engine for two minutes to purge air from the fuel lines after a fuel interruption, the flight manual lacks similar guidance for pilots facing air ingestion in the system.