Primary finding
Probable cause
The pilot’s failure to detect the tripped landing gear motor circuit breaker, which prevented the gear from fully locking in the down position, and subsequent collapse during landing.
Investigator assessment
Analysis narrative
The pilot of the retractable gear airplane reported that, while conducting a practice instrument approach, he felt the gear go down and thought that he saw three green landing gear lights, and no gear unsafe indicator light. The main landing gear touched down and the nose dropped down lower than normal. The propeller struck the ground and the left main gear collapsed. The airplane received substantial damage to the left aileron. According to the pilot, a mechanic discovered the landing gear motor circuit breaker had popped, which disabled the landing gear from fully extending and lock in the down position and disabled the warning light system. Once the circuit breaker was reset, the landing gear functioned normally.