What happened
The pilot was conducting an aerial application operation using a narrow gravel road approximately 20 feet wide. During the takeoff roll, the aircraft suddenly swerved to the right and departed the roadway, entering a ditch located beside the road. The impact resulted in substantial damage to the airframe.
The investigation
Post-accident examination of the aircraft revealed no evidence of mechanical failure regarding the landing gear or braking system. Specifically, inspection of the wheels and brakes showed no signs of grabbing or overheating that would explain the uncommanded rightward movement.
The aircraft was equipped with spray booms positioned approximately 2 feet 1 inch above the bottom of the wheels. The takeoff environment included tall grass, roughly 3 feet in height, lining the sides of the road, as well as the adjacent ditches. These obstacles likely interacted with the spray equipment or the lower fuselage during the deviation.
Findings
The pilot initially believed that the right main wheel had become locked, causing the swerve. However, this hypothesis was contradicted by the physical evidence. The takeoff was attempted heading north into a wind from the northwest at 5 knots, gusting to 7 knots. While the wind conditions were light, the combination of a narrow runway, tall vegetation, and spray boom clearance issues contributed to the loss of directional control.
Safety message
Pilots conducting aerial application operations on unpaved strips should be aware of the potential for spray booms or fuselage components to interact with tall grass or uneven terrain during takeoff. Ensuring adequate lateral clearance from obstacles is critical when operating in confined spaces.