What happened
On May 8, 2019, a Piper PA-28-161, registration PR-NPA, departed from Goiânia, Goiás, for a cross-country training flight intended to end in Juiz de Fora, Minas Gerais. The flight was being conducted by a flight instructor supervising a student pilot. During the first leg of the flight, the instructor decided to deviate from the original flight plan, bypassing a planned stop in Uberlândia to proceed directly to the final destination.
Approximately five and a half hours into the flight, the engine failed for the first time. The crew managed to restart the engine and decided to divert to São João Del Rei, Minas Gerais. However, during the approach to this new destination, the engine suffered successive failures. Unable to maintain engine operation, the crew performed a forced landing in a field of low vegetation. During the impact, the aircraft overturned, resulting in substantial damage to the airframe. Both occupants emerged uninjured.
The investigation
CENIPA investigators determined that the primary cause of the engine failure was fuel exhaustion. Although the flight plan estimated a fuel endurance of six hours, the aircraft's Pilot's Operating Handbook (POH) indicated a maximum endurance of approximately five hours and 27 minutes at 75% power. Post-accident inspection confirmed that while the fuel tanks were intact, no fuel remained in the tanks or engine components.
The investigation also examined the crew's decision-making and flight planning. The instructor had changed the flight plan without updated meteorological information for the destination. Furthermore, when the first engine failure occurred, the instructor mistakenly believed the issue was a mechanical failure rather than a lack of fuel. The investigation noted that the crew encountered instrument meteorological conditions (IMC) and that the destination airport had been closed for visual operations due to weather.
Findings
- The engine failure was caused by the exhaustion of fuel in the aircraft's tanks.
- Inadequate flight planning and a failure to properly evaluate aircraft performance and endurance parameters.
- Inadequate assessment of meteorological conditions following the change in flight plan.
- Deficiencies in the instructor's training, specifically regarding the ability to analyze and respond to operational changes and aircraft performance.
- An organizational safety culture characterized by informal procedures, such as the frequent omission of pre-flight briefings.