What happened
On August 22, 2022, at approximately 23:20 UTC, an experimental Explorer aircraft, registration PT-ZYK, was performing a private night ferry flight from Campinas to Bragança Paulista, Brazil. Approximately 20 minutes into the flight, the engine suffered a loss of power and subsequently stopped. The pilot performed an emergency landing in a cultivation area at Fazenda Nova Esperança. The aircraft sustained substantial damage, but the pilot emerged uninjured.
The investigation
CENIPA investigators examined the aircraft's maintenance records, fuel logs, and flight data from the cockpit's Multi-function Display (MFD). The investigation revealed that the aircraft's engine, a Lycoming IO-360-A1A, had exceeded its recommended inspection intervals, having flown 146 hours since its last 100-hour inspection. Furthermore, maintenance logs for the airframe, engine, and propeller were found to be outdated.
Regarding fuel management, the investigation found a discrepancy between the pilot's estimated fuel consumption and the actual consumption. While the pilot calculated usage at 40 L/h, the manufacturer's manual indicated a cruise consumption of approximately 46.56 L/h. Data from the MFD showed a sudden drop in fuel pressure and engine RPM just before the failure. Additionally, the investigation noted that the pilot was unaware of a manufacturer service bulletin (SB-INP-002) which advised against using the "BOTH" position on the fuel selector to prevent engine starvation if one tank empties.
Findings
- Inadequate flight planning, as the pilot's fuel calculations did not account for the actual higher consumption rate, leaving insufficient reserves for night VFR requirements.
- Improper fuel selector configuration, as the selector remained in the "BOTH" position, which, combined with the fuel depletion, likely caused the engine failure.
- Maintenance record discrepancies, including outdated logs for the airframe, engine, and propeller.
- Lack of awareness regarding the manufacturer's service bulletin regarding fuel selector usage.