Facts
The aircraft, a Piper PA-28-140 registered HB-PAP, was operated by Fluggruppe Seeland. The flight was a VFR training session with a student pilot and a flight instructor. The student, a German national born in 1938, had 90 total flight hours (73 on type). The instructor, a Swiss national born in 1980, held a CPL(A) with flight instructor rating and had 712 total hours (463 on type). The accident occurred on 4 March 2004 at 10:58 local time at Biel-Kappelen airfield, located about 7 km southeast of Biel. The runway was grass, 570 m long and 30 m wide, with a displaced threshold on runway 23. The weather was calm with wind from west-northwest at 1-2 knots, visibility around 15 km, temperature 3°C, dewpoint -4°C, and QNH 1026 hPa.
Sequence of Events
The student and instructor met at Grenchen airfield where the aircraft had been parked overnight. After briefing and external check, they departed Grenchen runway 25 at 10:35. Over Petersinsel, the student practiced simulated approaches. They then planned touch-and-go landings at Biel-Kappelen, the home base. On the first approach to runway 05, a go-around was performed. During the downwind leg, the wind sock indicated calm conditions. The instructor assisted the student with checks and manipulations.
The final approach was stable. The instructor completed the final check and turned off carburetor heat. Flaps were set to position 3 (40°). The aircraft touched down approximately 140 m after the runway threshold. Due to soft ground, deceleration was stronger than expected. The instructor ordered a go-around and set flaps to position 2 (25°). The student hesitated briefly, then advanced the throttle. The engine did not accelerate properly. Realizing the performance was insufficient, the instructor aborted the takeoff, retarded throttle and mixture, and began braking. However, the aircraft could not be stopped before the runway end. It crossed the adjacent main road; the instructor attempted to raise the nose using elevator, but the nose gear struck the road embankment. The aircraft came to rest 15 m beyond the road in a field with the nose wheel broken and propeller bent. Both pilots evacuated unhurt. The aircraft sustained damage to the nose gear, propeller, and parts of the engine cowling. Minor crop damage was also reported.
Investigation
The investigation found no technical defects that could have contributed to the accident. An engine run-up conducted on 8 May 2004 showed that the engine functioned correctly at idle and up to 1300 RPM, but during acceleration the report's sentence is incomplete and no further details are provided. The aircraft's mass and center of gravity were within limits. The runway condition was reported as soft due to moisture, and the instructor had anticipated the ground to be frozen based on a temperature of -1°C reported in the Grenchen ATIS at 09:50.
Cause
The accident was attributed to the aircraft overrunning the runway, caused by the late abort of takeoff after a too long landing during a touch-and-go. Contributing factors included delayed or insufficient engine performance restoration and poor assessment of the runway condition.