Cessna 177 N2112Q accident near Palm Springs, California

Probable cause

The failure of a shaft seal at the nose gear retraction/extension actuator, which resulted in a loss of hydraulic fluid and a main landing gear collapse during landing.

NTSB analysis

The pilot reported that during the takeoff initial climb, after the landing gear was retracted, the landing gear's hydraulic pump electric motor continued to run, even though the landing gear appeared to be fully retracted, as viewed in the landing gear mirror. The pilot then attempted to extend the landing gear normally, but the landing gear would not indicate down and locked. Subsequently, for over an hour, the pilot attempted to manually extend the landing gear, using the emergency manual gear extension hand pump, but he could see in the mirror that the landing gear was only partially extended. During the subsequent emergency landing, the main landing gear collapsed and the airplane skidded to a stop on the runway. The right stabilator sustained substantial damage.

A postaccident examination revealed that the landing gear system was empty of hydraulic fluid. After the system was serviced with hydraulic fluid and operated, a leak was found at the nose gear actuator due to the failure of a shaft seal. The tests revealed that the landing gear extension process could not be completed, and the manual landing gear pump did not have sufficient fluid remaining to extend all three landing gear. The airplane logbooks revealed no records of service to the nose gear actuator and shaft seal and each were the original manufactured parts.

Text from the NTSB. Open the NTSB docket for GAA16CA074 for the full record.