What happened
On September 23, 2020, an AT-3 R100, registration SP-TPE, departed from Warsaw Babice Airport (EPBC) for a scheduled training flight. The crew consisted of an instructor and a student pilot. Approximately 30 minutes into the flight, the crew received a "check fuel pressure" warning, as the fuel pressure indications dropped nearly to zero.
Upon activating the electric fuel pump, the pressure readings returned to normal levels. The crew declared an emergency with Flight Information Service (FIS) and initiated a return to the airfield. During the approach to the airport, the crew briefly deactivated the electric pump for approximately 10 seconds to test the system; during this interval, the pressure readings remained within normal parameters.
The investigation
The investigation focused on the mechanical performance of the fuel system during the period of the pressure drop. The PKBWL examined the functionality of the engine-driven fuel pump and the response of the electrical fuel pump during the emergency procedure.
Findings
- The primary cause of the incident was the malfunctioning of the engine-driven fuel pump.
- No contributing circumstances were identified for this occurrence.