Shortly after taking off from RAF Syerston the pilot noticed that the engine was not running at maximum speed and, as the aircraft climbed through 200 ft, it began running roughly with its speed decreasing. The pilot reduced the power setting, which resulted in the engine running smoothly for a short while, but when increased power was demanded to initiate a climb and return to RAF Syerston, the engine again began to run roughly and failed to respond to throttle inputs. The pilot carried out a forced landing in a crop field which resulted in the collapse of the nose landing gear and damage to the lower fuselage and wing mounts. In the absence of any identifiable technical defect, it was considered that fuel vapour locking, caused by the use of un-insulated fuel lines within the engine compartment, had caused the loss of power.
Published 10 December 2014