What happened
On 1 October 2000, a Piper PA-28-181, registration G-BOXY, was being operated by a flying club for a trial lesson at Netherthorpe Airfield in Nottinghamshire. The flight was carrying a pilot and three passengers. During the takeoff roll on Runway 24, the pilot utilized a 10° flap setting. While the aircraft initially appeared to accelerate normally, the pilot reported a perceived loss of power shortly after becoming airborne, which prevented the aircraft from climbing.
As the aircraft approached the perimeter hedge, the pilot pitched the nose up to attempt to clear the obstacle. This maneuver triggered the stall warning and caused the right wing to drop. Recognizing that the aircraft lacked the necessary performance to continue the climb, the pilot closed the throttle and performed a controlled landing in a nearby field of sugar beet. The aircraft sustained no fatalities or injuries, though it suffered minor damage to a nosewheel spat.
The investigation
Investigators examined the engine and conducted a post-incident flight test, which confirmed the engine was functioning normally and performing according to published figures. Analysis of a video recording made by a passenger further supported this, as the audio frequency spectrum showed that engine RPM remained constant from the start of the takeoff roll until the stall warning occurred.
Because the occupants were not weighed prior to departure, investigators used post-event data to estimate a total occupant weight of approximately 355 kg. Combined with an estimated fuel load of 65 kg and the aircraft's empty weight, the estimated takeoff weight was 1,140 kg, which was near the maximum allowable limit of 1,160 kg.
Calculations revealed that the required takeoff distance for the conditions—accounting for the grass surface, the 1.9% upslope, and CAA-recommended safety factors—exceeded the 488 metres of available runway. Specifically, even using more optimistic figures, the required ground roll was estimated to be between 512 and 587 metres.
Findings
- The primary cause of the incident was insufficient runway length to safely complete the takeoff under the prevailing conditions.
- The pilot used a 10° flap setting, for which no specific performance data was provided in the Pilot's Operating Handbook, rather than the recommended 25° for short-field operations.
- There was no evidence of engine malfunction or power loss.
- The aircraft was operating near its maximum takeoff weight.
- The flying club lacked formal written guidance regarding the application of performance safety factors or preferred flap settings for its members.
Safety action
- The CAA is encouraged to prompt flying clubs to establish and implement written policies regarding the use of recommended performance factors and to provide clear guidance to instructors and members.