What happened
On 12 December 1998, a Piper PA-28-181, registration G-BDSB, was involved in an accident during a private flight near Hungerford, Berkshire. After an initial successful landing on a grass strip, the pilot returned to the field approximately two hours later to perform a takeoff. Based on an assessment of the ground firmness and calculations using the aircraft flight manual and safety leaflets, the pilot determined that the 1,650-foot strip provided sufficient margins for the departure.
During the takeoff roll, the aircraft achieved full power and initially accelerated well, reaching 40 knots as planned. However, the aircraft then failed to accelerate further to the necessary rotation speed of 43 to 45 knots. As the end of the strip approached, the pilot rotated the aircraft. While the Piper PA-28-181 became airborne, it was unable to clear a hedge located at the field boundary. The aircraft struck the hedge and came to rest in an adjacent field, resulting in substantial damage to the nose landing gear, the tailplane, and the rear fuselage. There were no injuries to the pilot or the passenger.
The investigation
The investigation examined the takeoff performance and the condition of the airfield. It was noted that while the pilot had initially assessed the strip as firm, the surface at the latter part of the takeoff roll was found to be softer than the starting section. This change in surface condition was likely caused by a rain shower that had occurred during the two-hour interval when the pilot was away from the field.