Incident Overview
A pilot conducted an intentional gear-up landing after numerous attempts to extend the landing gear were unsuccessful. The landing was performed with only the left main landing gear retracted, as the pilot was unable to lower it.
Investigation Findings
Examination of the aircraft revealed that a small steel nut had jammed the left main landing gear door unlatching mechanism. The nut was found in a position that prevented the landing gear and doors from actuating properly.
Possible Origin of the Stray Nut
The stray nut could have been thrown into the wheel well by the tire while the aircraft was on the parking ramp, taxiway, or runway. It may also have been inadvertently left in the wheel well during previous maintenance activities. The nut likely fell into the jamming position after the gear was retracted on the incident flight.
Conclusion
This occurrence is considered an isolated incident. The landing gear system was rendered inoperable due to the presence of the stray nut in a critical mechanism.