What happened
On October 17, 2013, an Evektor Eurostar EV 97 SL ultralight aircraft was engaged in a cross-country flight from Worms to Marl. After refueling in Marl, the pilot began the return flight to Worms but decided to perform a precautionary landing at the Koblenz-Winningen airfield due to a perceived loss of engine power. Witnesses observed the aircraft approaching the airfield with an unusually deep, low-pitched engine sound.
Upon landing, the pilot conducted an oil check, which revealed no defects. Following a discussion with the airfield's maintenance association regarding potential carburetor icing, the pilot decided to continue the flight. At 16:43, the aircraft departed from runway 24. Shortly after takeoff, as the aircraft reached approximately 200 feet above the ground and entered a right-hand turn, the pilot radioed that the engine was experiencing power issues. The aircraft subsequently stalled over the right wing and plummeted nearly vertically into an allotment garden area adjacent to the airfield. The impact caused a post-crash fire that destroyed the aircraft. Two fatalities were recorded.
The investigation
The BFU investigation examined the aircraft's maintenance history, the pilot's experience, and the engine's performance. The aircraft had recently undergone a 100-hour inspection and a propeller replacement. Investigators also reviewed the manufacturer's operating manual, which specifically warns that Rotax 912 UL engines are not certified for general aviation and that pilots must be prepared for potential engine failures. The investigation also noted the meteorological conditions, which included light drizzle and wind gusts of up and to 25 knots at the time of the second departure.
Findings
- The aircraft experienced a loss of engine power during the initial climb phase.
- Witnesses reported a slow takeoff roll and an unsteady engine running sound.
- The pilot had noted power issues during the previous landing and had considered carburetor icing as a possibility.
- The aircraft's engine was destroyed by the post-crash fire, preventing a detailed mechanical analysis of the power loss.