What happened
On March 19, 2016, a Robin DR 400/180 R, registration HB-EQN, was performing an annual internal check flight at Schaffhausen airfield (LSPF). The flight, conducted by a pilot accompanied by an instructor, involved a specific training program including touch-and-go landings and a full-stop landing maneuver.
During the third approach for a touch-and-go, the aircraft touched down slightly past the predetermined touchdown point. Following this, the instructor reduced engine power to initiate a planned full-stop landing exercise. On the final approach, the aircraft was flying higher and faster than intended, resulting in a touchdown approximately 250 meters before the end of the runway.
Upon touchdown, the pilot applied the wheel brakes; however, due to the smooth surface of the runway's plastic reinforcement plates, the braking effectiveness was limited. To gain more rolling distance, the instructor directed the aircraft toward the right side of the runway. The aircraft exited the paved surface, crossed a farm track, and traveled approximately 30 meters onto soft agricultural land before coming to a halt. During the excursion, the nose gear sank into the soft ground, causing the propeller to strike the earth and the engine to stall.
The investigation
The investigation focused on the flight parameters during the landing sequence and the effectiveness of the braking action on the specific runway surface. Investigators examined the aircraft's performance and the environmental conditions at the time of the incident.
Findings
- The primary cause of the overrun was that the aircraft approached the runway with excessive height and speed.
- The use of wheel brakes provided insufficient deceleration due to the smooth texture of the plastic mats installed on the runway to prevent gear sinking.
- There were no evidence of pre-existing technical malfunctions that contributed to the event.
Safety action
The crew sustained light injuries, and the aircraft suffered damage to the nose gear and propeller.