Occurrence
On 20 June 2015 at 12:00 local time, a privately operated Cessna 172P (registration HB-CIE) departed from Thun airfield (LSZW) for a flight to Freiburg im Breisgau (EDTF). The pilot, a Luxembourg citizen born in 1970, was accompanied by one passenger. During the takeoff roll, the pilot became uneasy because the aircraft's acceleration did not match his recollection from recent check flights. Approximately halfway down the runway, he doubted the aircraft would become airborne and reduced power to abort the takeoff. By that time, the aircraft had already lifted off to about one meter above the ground. The stall warning then sounded. Convinced that a safe takeoff was no longer possible, the pilot fully rejected the takeoff. The aircraft settled back onto the runway but could not be stopped on the remaining pavement. It avoided a metal barrier in the overrun area, crossed an adjacent tank track, and came to rest in tall grass a few meters beyond.
Aircraft and Pilot Information
The aircraft was a F172P (Cessna 172P) owned and operated by Motorfluggruppe Thun, based in Thun. The pilot held a Private Pilot License (Aeroplane) with 273 flight hours total, including 170 hours on the accident type. He had flown only 2 hours in the previous 90 days, all on type. Prior to the accident flight, he had completed three check flights with an instructor on 28 May and 9 June 2015, all flown at partial load (two occupants and little fuel). The instructor assessed his performance as good. For the accident flight, the pilot fully fueled the aircraft and loaded it with baggage for a two-week trip to Norway. He believed the takeoff distance under the prevailing conditions—dry runway—would be sufficient.
Investigation Findings
Post-accident examination found no technical limitations or malfunctions with the aircraft. The pilot reported that maintenance had been performed on the aircraft just before his flight, which made him more attentive to engine performance during the takeoff. He noted the engine tachometer indicated slightly over 2300 rpm throughout the takeoff roll. The investigation considered that, given the weather conditions, a light tailwind component could not be ruled out, though no precise measurement was available.