What happened
On June 19, 2013, a Piper PA 46-310P Malibu departed from Rottweil-Zepfenhan for a flight to Augsburg. During the flight, after passing Ulm, the pilot experienced engine roughness and power fluctuations, which appeared to be caused by insufficient fuel supply. To rectify this, the pilot switched the electric auxiliary fuel pump to the "High" position, which restored normal engine operation.
During the final approach to runway 07 at Augsburg, the pilot attempted to increase engine power but the engine failed to respond. Due to the low altitude, the pilot initiated an emergency landing. During the descent, the aircraft's right wing struck a wooden pole, and the plane subsequently struck several trees before impacting the ground. The impact resulted in one person seriously injured and significant damage to the aircraft and local property.
The investigation
The BFU examined the aircraft's engine components, including the fuel pump, fuel metering unit, and manifold. While the engine-driven pump showed some leakage, investigators determined this was a result of the crash itself. Testing on a similar aircraft confirmed that running the engine at power settings while the auxiliary pump is in the "High" position causes the engine to fail to maintain RPM.
The investigation also reviewed the pilot's credentials and training. The pilot held a valid PPL(A) but lacked the specific type rating for the PA 46. Furthermore, the pilot had only approximately one hour of flight time in this specific piston-engine model. The investigation noted that the pilot had received a brief orientation on engine operation from the aircraft owner the previous day, but this was insufficient to ensure full familiarity with the complex fuel system.
Findings
- The primary cause of the accident was the mismanagement of the auxiliary fuel pump, which the pilot left in the "High" position after the initial engine issue.
- According to the Pilot’s Operating Handbook, using the "High" setting during normal engine operation causes excessive fuel pressure and an overly rich mixture, preventing the engine from producing power.
- The pilot's lack of a type rating and limited experience in the PA 46 contributed to the error.
- The pilot failed to switch the pump back to the "Low" position to ensure continuous, stable fuel supply during the approach.