Incident Overview
During a night landing, the aircraft touched down with its landing gear only partially extended. The pilot reported that he typically dims all panel lights during night flights to enhance his night vision. While attempting to increase the brightness of the landing gear indicator light by turning a knob counterclockwise, he inadvertently pressed a "press and test" knob. This action caused a false indication that the gear was down and locked.
Post-Accident Examination
After the incident, mechanics inspected the aircraft and noted that the circuit breaker for the landing gear had popped out. They reset the circuit breaker and placed the aircraft on jacks to cycle the landing gear. The gear operated normally through multiple cycles, and no anomalies or mechanical malfunctions were detected.
Pilot Actions
The pilot stated that the accidental depression of the test knob occurred during his effort to illuminate the gear indicator light. The false indication led him to believe the gear was properly extended and locked, resulting in the landing with the gear not fully deployed.