What happened
On June 4, 2021, a Diamond DA 42NG, registration EC-MNP, operated by Flight Training Europe (FTE), was performing a training flight at Jerez La Parra Airport. During the second asymmetric circuit, the instructor decided to perform an unplanned "short approach" maneuver, simulating a complete engine failure by reducing power to idle while in the downwind leg.
As the aircraft transitioned toward the runway, the pilot used a significant left bank angle to correct the aircraft's alignment with the runway. The aircraft touched down at 13:40 local time with a high descent rate of approximately -930 fpm and a steep left bank angle of 24-27 degrees. This unstable touchdown caused the left main gear axle to fracture due to an instantaneous lateral overload for which the gear was not designed.
The left wheel detached and struck the left flap, while the aircraft continued to slide along the runway for 540 meters, supported by the fractured trailing arm. The excursion caused the left propeller to strike the pavement and triggered a small fire in the dry vegetation near the runway edge, likely caused by sparks from the metal structure scraping the asphalt. The two occupants, an instructor and a student, were uninjured and evacuated the aircraft on their own.
The investigation
The CIAIAC investigation examined flight data from the aircraft's Garmin 1000 GPS, airport surveillance footage, and maintenance records. Investigators analyzed the aircraft's flight path, noting that the aircraft was significantly misaligned with the runway centerline during the final stages of the approach. The investigation also reviewed the instructor's decision-making process and the student's control inputs, specifically the use of aileron rather than rudder to correct the lateral drift.
Findings
- The primary cause of the accident was the incorrect execution of the approach, which resulted in the aircraft touching down with an excessive left bank angle and a high descent rate.
- The instructor decided to perform an unplanned maneuver that was not part of the scheduled training lesson.
- The instructor failed to provide effective supervision of the maneuver and did not instruct a "go-around" (go-around/motor y al aire) when the aircraft's alignment became critical.
- The student attempted to correct the lateral displacement using aileron input rather than rudder, contributing to the unstable touchdown.
- The left main gear axle failed due to lateral overstress during the unstable landing.