Primary finding
Probable cause
The pilot/builder’s inadequate installation of a nosewheel steering component, which resulted in a shimmy and a loss of directional control during the takeoff roll.
Investigator assessment
Analysis narrative
During the takeoff roll, the nosewheel experienced a shimmy, and the pilot was unable to maintain directional control. The gyrocopter rolled onto its left side, exited the side of the runway, and came to rest in the grass. During the rollover, the main rotor mast sustained substantial damage. A postaccident examination of the gyrocopter revealed a loose bolt in the nose gear steering linkage, which allowed the nosewheel to shimmy. The pilot, who was also the builder, was testing the newly built gyrocopter.
Source record
Factual narrative
The pilot/builder was planning a short flight above the runway for the purpose of testing the newly built gyrocopter. During the takeoff roll, the nose wheel experienced a shimmy and the pilot was unable to maintain directional control. The gyrocopter rolled onto its left side and exited the side of the runway before coming to rest in the grass. During the rollover, the main rotor mast was substantially damaged. A postaccident examination of the gyrocopter revealed a loose bolt in the nose gear steering linkage which allowed the nose wheel to shimmy.