Overview
On 21 September 2008 at 1545 UTC, a Reims Cessna F152, registration G-BLZE, collided with a hedge at the end of a grass runway at Farway Common Airfield, Devon. The aircraft was on a private flight with one pilot and one passenger. Neither occupant was injured. The aircraft sustained damage to its wings, engine, and nose.
History of the Flight
The pilot, aged 31 and holding a Private Pilot’s Licence with 135 total hours (130 on type), was conducting a cross-country flight with multiple legs. Having departed Redhill, he landed at Manston and Bembridge, where the aircraft was refueled to full, and then arrived at Farway Common. This was the pilot’s first visit to the unlicensed airfield, which has two 550 m grass runways (10/28 and 18/36). The landing on Runway 10 was uneventful.
Approximately half an hour later, the pilot and passenger prepared for departure back to Redhill. The previously light easterly wind had become calm, so the pilot elected to depart from Runway 10. Pre-takeoff engine run-up checks were normal. During the takeoff roll, the aircraft accelerated to about 40 to 45 KIAS, but the pilot decided to abort the takeoff, believing he would not reach the normal rotate speed of 50 KIAS and achieve a safe climb. The aircraft came to a safe stop. While attempting to vacate the runway, full power was insufficient to start taxiing; the pilot and passenger pushed the aircraft off the runway to clear it for a landing aircraft. The pilot suspected a brake might have been stuck, which pushing the aircraft seemed to free. He then spoke with the airfield operator, who recommended a takeoff from Runway 28 as it was downhill and the wind was calm.
The pilot applied full power while holding the brakes for the takeoff from Runway 28, with flaps set to 10°. The engine sounded normal, and the aircraft accelerated to 45 KIAS but would not accelerate further. Again, the pilot aborted the takeoff. According to a witness, the abort occurred about 150 to 200 m from the runway end. The pilot reported that one brake did not appear to be working, and he could not stop the aircraft before it struck the hedge. The right wing fuel tank began leaking, but no fire ensued.
Aircraft and Pilot Information
The aircraft was a 1979 Reims Cessna F152 powered by one Lycoming O-235-L2C piston engine. Its maximum takeoff weight was 758 kg; at the time of the accident, the weight was approximately 736 kg. The commander held a Private Pilot’s Licence and was 31 years old. His total flying experience was 135 hours, of which 130 were on type, with 9 hours in the last 90 days and 7 hours in the last 28 days.
Takeoff Performance
At the time of the accident, the temperature was 18°C and pressure altitude was 474 feet. The aircraft’s Flight Manual lists takeoff ground roll as 252 m and distance to 50 ft as 466 m for a paved, level, dry runway with zero wind, flaps 10°, and full throttle prior to brake release. For a dry grass runway, the manual states distances should be increased by 15% (ground roll: 290 m; to 50 ft: 504 m). The CAA’s Safety Sense Leaflet 7 recommends a 1.33 safety factor for single-engine aircraft with unfactored data, giving a ground roll of 386 m and distance to 50 ft of 670 m. A more conservative estimate, adding 20% for grass up to 20 cm length, results in a ground roll of 459 m and takeoff distance to 50 ft of 744 m (including the 1.33 factor). The runway length was 550 m.
Discussion
Based on the manufacturer’s data, a safe takeoff within 550 m would have been achievable, assuming the aircraft and engine were in good condition. However, effects of grass runway surface condition are difficult to predict; applying the CAA’s conservative estimates indicated a safe takeoff may not have been possible. Within the distance available, the aircraft should have been able to accelerate to 50 KIAS, but the reason for the airspeed staying at 45 KIAS could not be explained. A slightly stuck brake may have reduced acceleration. At the abort point, insufficient runway likely remained for a safe stop, and the downslope would have increased braking distance.
Probable Cause
The investigation did not state a probable cause.