Uplock

The left brake line, strut actuator and uplock actuator temperature measurements rose significantly, 20 to 30 degrees in five minutes. ❋ Unknown (2003)

At 7: 53, as we were passing over California, we've identified that a fourth left brake line strut actuator and uplock actuator temperature measurements rose significantly. ❋ Unknown (2003)

The left uplock assembly, upper attachment bolt, nut and cotter pin assembly used to mount the left main landing gear to the structure were installed, but did not engage the uplock assembly. ❋ Unknown (2010)

During its investigation the NTSB determined the aircraft underwent extensive maintenance that included the removal, replacement and visual inspection of the left and right main landing gear uplock assemblies. ❋ Unknown (2010)

As a result the uplock assembly pivoted about to the lower bolt. ❋ Unknown (2010)

Since the upper attachment bolt did not engage the uplock assembly, the left main landing gear remained in the up-and-locked position, and did not respond to pilot commands to lower before landing. ❋ Unknown (2010)

NTSB's investigation revealed that the mechanic who replaced the left uplock assembly had not completed uplock assembly work previously, received no on-the-job training for the task and was not supervised during the procedure. ❋ Unknown (2010)

The NTSB's investigation revealed that post-maintenance inspections were not adequate to detect mis-rigging of the uplock assembly. ❋ Unknown (2010)

Cowlings are secure, oil is present at the proper level, all the control surfaces move in the right direction, inspection ports are all closed with fasteners in, gear is lubricated and the uplock springs are working, and so on. ❋ Unknown (2008)