What happened
Following takeoff, the pilot determined that the landing gear was failing to retract properly. Believing that the gear remained in the down and locked position, the pilot decided to continue the flight to the destination airport.
During the landing phase, the aircraft touched down and rolled on the main landing gear wheels. As the aircraft proceeded along the runway, the nose landing gear lowered onto the surface. Upon contact with the runway, all three landing gear assemblies retracted.
The investigation
A post-accident examination of the aircraft revealed that the landing gear retraction motor had separated from its rear bulkhead attachment. Investigators found that the rivets of the component had fractured in the contact surface plane. The observed deformation and smeared features were consistent with overstress, though the specific timing of when this overstress event occurred could not be determined.