What happened
On August 10, 2023, a Piper Meridian departed Reichelsheim carrying a flight instructor and two students for a training flight involving circuit and landing practice to obtain an SET rating. Upon arriving at Kassel-Calden airport at 15:42, the crew performed two touch-and-go landings. Following these, the aircraft landed and taxied to a maintenance facility because a continuous audible warning from the gear warning horn had been occurring whenever the landing gear was retracted. This warning could not be silenced using the mute button due to a sensor malfunction.
After a maintenance check flight confirmed a fault in the torque sensor, the crew decided to perform additional circuit training before concluding the flight. The aircraft departed again at 17:37 and completed three circuits. During the third landing, performed with a 0-flaps configuration on runway 27, the aircraft touched down with the landing gear retracted. The impact caused heavy damage to the propeller and the underside of the fuselage. All three occupants remained uninjured.
The investigation
The BFU investigation focused on the sequence of events leading to the gear-up landing and the technical state of the aircraft's warning systems. The investigation examined the functionality of the gear warning horn and the impact of the previously identified torque sensor error. The investigation also reviewed the cockpit environment, specifically the workload during the final approach and the crew's familiarity with the persistent audible warning that had been active throughout the flight session.