What happened
The pilot reported observing frost on the wings prior to departure but determined it was not significant enough to warrant concern. He proceeded with takeoff from a 2500-foot airstrip carrying a load consisting of paraquat and water. Conditions included a slight tailwind. During the ground roll, the aircraft failed to accelerate as expected because the engine did not appear to be developing full power. In an attempt to reduce weight, the pilot actuated the dump handle to release part of the cargo. Despite this action, the aircraft struck a 5-foot bank near the end of the runway.
The investigation
A post-accident examination of the airframe and engine revealed no pre-crash mechanical malfunctions or failures, with the exception of considerable lead deposits on the lower spark plugs. Notably, the engine operated normally during subsequent run-up checks. Investigators found that the propeller control lever was positioned less than halfway from the high pitch setting.
Findings
The pilot stated he had exercised the propeller control several times before takeoff but indicated he may have mistakenly left it in a high pitch, low RPM position. This configuration prevented the engine from producing the necessary power for a safe departure with the loaded aircraft.
fuel exhaustion is not the cause; rather, the critical factor was improper propeller setting. The aircraft type involved was a single-engine piston aircraft. No injuries were reported in this incident.