What happened
The pilot attempted a westerly departure from a 2,000-foot grass runway characterized by a 2 to 3 percent uphill slope. The pilot's personal criteria for such a departure required a wind from the west of at least 8 knots. During the takeoff roll, the aircraft's tail wheel engaged the top strand of a barbed wire fence. This caused the aircraft to collide with 35-foot pine trees located west of the airstrip. The pilot reported that engine power seemed insufficient to clear the trees, although there was no perceptible loss of power output felt or heard during the event.
The investigation
The engine was sent to the Teledyne Continental Motors factory for a teardown inspection conducted under FAA oversight. The inspection revealed no abnormal conditions within the core engine or its components.
Investigators noted that the aircraft's Pilot Owners Handbook (POH) requires operation in the restricted category when the aircraft exceeds 3,300 lbs or is equipped with special agricultural equipment. Performance data for the restricted category is limited; specifically, the POH contains a chart for "Takeoff Distance with Dispersal Equipment" that only accounts for sea level, standard atmospheric conditions, zero wind, a hard surface, and a level runway with 10 degrees of flaps. The POH also includes cautions regarding the adverse effects of soft runways and long grass, as well as the increased air distance over obstacles when agricultural equipment is installed.