Incident Overview
A pilot experienced a loss of control during takeoff when the seat slid backward after takeoff power was applied. The airplane had a secondary friction lock designed to prevent seat movement, but it only halted the slide momentarily before the seat continued moving aft. The pilot responded by reducing power, but the airplane began to drift left. Unable to reach the rudder pedals, the pilot could not correct the deviation.
Sequence of Events
As the airplane continued to drift left, it departed the left side of the runway. After leaving the runway surface, the airplane executed a turn of approximately 270 degrees. During this maneuver, the right main landing gear collapsed. The incident ended with the airplane coming to rest off the runway.
Damage
The right main landing gear collapsed during the ground excursion. Additional damage may have occurred, but the report does not specify details beyond the gear collapse.
Probable Cause
The report does not state a probable cause for the incident.