What happened
The aircraft was preparing for flight when the pilot conducted his preflight inspection. During this process, the pilot failed to remove the control lock from the elevator. Consequently, the elevator remained locked throughout the takeoff roll, leaving no pitch control available to the pilot.
As the aircraft accelerated down the runway and reached flying speed, rotation was attempted. The aircraft became airborne; however, because the elevator was locked, its pitch angle continued to increase uncontrollably. The aircraft eventually decelerated past its critical angle of attack and stalled. It then descended out of control before crashing and burning.
The investigation
The investigation focused on the mechanical state of the aircraft at the time of the accident. Examination confirmed that the elevator control lock had not been removed prior to the flight. This physical obstruction prevented any pitch input from affecting the elevator surface during the critical takeoff phase.