Accident Sequence
During the takeoff roll, the airplane used approximately half of the 8,602-foot runway. After becoming airborne, the aircraft pitched nose-down briefly over the runway during the initial climb. The pilot radioed that he was experiencing a problem with the elevator, which required 'full back pressure' to keep the nose up, and that he was returning to land. After maneuvering around the airport, the aircraft pitched 70 to 80 degrees nose-down and dove into terrain off the approach end of the runway.
Examination Findings
Examination of the wreckage revealed that the bolt securing the elevator trim tab pushrod to the actuator was missing. The pushrod had become wedged inside the elevator, resulting in an extreme tab-up (nose-down) condition.
Maintenance and Preflight Reports
The aircraft had undergone an annual inspection two days and five flight hours earlier. The inspecting mechanic (IA) reported that no maintenance was performed on the trim tab system and that he was certain the bolt was properly safetied. Another pilot who flew the aircraft on the day of the accident reported that he found the pushrod to be secure during his preflight inspection.
According to the 402B Pilot Operating Handbook, the aircraft should have required about 1,200 feet for the takeoff ground roll.