On July 24, 1986, a Schweizer G164A (registration N8379) operated by Cameron Wischer was involved in an aviation accident near Grandin, ND. Investigators recorded the probable cause as: The pilot's failure to maintain directional control during takeoff due to soft runway conditions and contact with vegetation. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
An agricultural aircraft experienced a loss of directional control during takeoff from a sod strip with soft center conditions, resulting in a cartwheel incident.
What happened
The pilot was attempting to initiate a takeoff from a sod runway measuring 2600 feet by 50 feet. The aircraft was loaded with a full fuel capacity of 36 gallons and an additional 160 gallons of M22 fungicide. Conditions on the airfield were compromised by recent rains, which left the center portion of the runway notably soft.
As the pilot began the takeoff roll along the right side of the runway, the right wing and the attached spray boom made contact with tall grain stalks growing along the edge of the strip. This interaction caused the aircraft to spin around and slide sideways. The left wing tip subsequently dug into the ground, leading the aircraft to cartwheel.
The investigation
The physical evidence indicated that the soft surface conditions contributed to the loss of control. The contact with vegetation on the right side initiated the uncommanded rotation and lateral movement.
Probable cause
The pilot's failure to maintain directional control during takeoff due to soft runway conditions and contact with vegetation.