What happened
On July 10, 2016, a Diamond DA 40 NG was conducting a training flight for an instrument rating when it was involved in an accident near Merenberg. The flight, which began in Egelsbach, was intended to include ILS approaches at Siegerland Airport. However, due to parachute jumping activities in the approach sector, the crew diverted to perform airwork exercises south of the airport.
During this diversion, the flight instructor decided to conduct simulated engine failure landing exercises. During the second attempt, the instructor took control of the aircraft. As the aircraft descended toward a grain field, the pilot applied full power to initiate a go-around. However, the decision to apply power was made too late. The aircraft entered the tall crops at a low speed, causing the landing gear to strike high vegetation before the aircraft made a hard impact. The aircraft sustained heavy damage, including a broken fuselage near the tail and broken landing gear, but there were no injuries to the flight instructor or the student.
The investigation
The BFU examined the FADEC (Full Authority Digital Engine Control) data, which provided a high-resolution record of engine parameters. The data confirmed that the engine responded correctly to the power input, with increases in manifold pressure, common rail pressure, and propeller RPM recorded immediately after the power lever was moved to 99%. The investigation also reviewed the training organization's manuals and the student's training records.
Findings
- The primary cause of the accident was that the decision to initiate the go-around was made too late during the simulated engine failure exercise.
- The chosen landing site featured rising terrain and tall vegetation, which interfered with the landing gear.
- The simulated engine failure exercise was not a part of the approved training curriculum or the specific mission syllabus.
- The flight was conducted under VFR conditions despite being part of an instrument rating course, and the student had not filed an IFR flight plan as instructed.
- The flight instructor's decision to perform unauthorized training maneuvers contributed to the occurrence.