What happened
On December 19, 2006, a Piper PA3-220T was conducting a local training flight at Friedrichshafen Airport with a flight instructor and two students on board. Following an initial landing and a subsequent go-around, the crew attempted a third approach to complete the landing sequence. During this final approach, the aircraft climbed again, prompting the instructor to initiate a go-around procedure.
While at a very low altitude and low airspeed, the aircraft veered to the right. The aircraft crossed a taxiway and headed toward an aircraft hangar. The aircraft eventually touched down with a leftward bank and a sliding motion. Upon impact, the left main landing gear collapsed, causing the left wing and left propeller to make contact with the ground. The aircraft came to a stop on a grass strip between the taxiway and the paved area in front of a building. There were no injuries to the occupants, but the aircraft sustained heavy damage.
The investigation
The BFU examined the aircraft's performance and mechanical condition following the incident. During post-accident testing, investigators observed that when the right engine was tested with the fuel mixture and propeller controls set to the "high" position, the engine began to sputter, the RPM dropped below 1000, and the engine eventually stalled. However, the engine operated normally when the mixture was set to a half-retarded position or when the electric fuel pump was set to "low."
Additionally, the investigation revealed that the aircraft had experienced two previous aborted takeoffs on November 24 and December 3, 2006, because the right engine failed to produce sufficient takeoff power. A maintenance check at a repair shop had previously identified that the right engine was running too rich in the mid-power range, and this finding had been communicated to the operator. No records indicated that any corrective actions had been performed on the engine following that discovery.