What happened
On 16 September 2012, a pilot was operating an amateur-built Pottier P 180 S at Aachen-Merzbrück airport for a scheduled annual inspection. The aircraft had been parked outdoors under a cover for approximately six weeks following a previous flight from Switzerland in August.
Prior to the flight, the pilot performed maintenance by replacing spark plugs and conducted a standard pre-flight inspection, which included a visual fuel check and draining fuel from the drain valve. After starting the engine and verifying all engine parameters, the aircraft departed from runway 26 at 14:50 local time.
The initial climb to approximately 400 ft proceeded without incident. However, as the pilot attempted to retract the flaps, the engine suffered a total failure. The pilot immediately initiated an emergency landing procedure, maneuvering the aircraft toward a field located between a highway and the airfield. During the turn, the pilot notified the tower controller of the engine failure and the intended emergency landing. The aircraft struck a roadside embankment before sliding 14 meters across a field, resulting in the aircraft being heavily damaged and the pilot suffering serious injuries.
The investigation
The BFU examined the wreckage and the circumstances surrounding the flight. Investigators noted that the aircraft's fuel pumps were still operational upon arrival at the crash site. The investigation also reviewed the pilot's credentials, noting a valid PPL-A and ultralight license, as well as the aircraft's maintenance history, including a recent annual inspection completed in July 2012.
Physical examination of the Pottier P 180 S revealed significant structural damage, including a broken propeller blade, a downward-bent engine mount, and a fractured fuselage behind the wings. The landing gear was also severely impacted, with the nose gear torn off and the main gear deformed.