The pilot reported that during the takeoff initial climb, after the landing gear was retracted, the landing gear’s hydraulic pump electric motor continued to run, even though the landing gear appeared to be fully retracted, as viewed in the landing gear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.
He then attempted to extend the landing gear normally, but the landing gear would not indicate down and locked. Subsequently, for over an hour, he 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 at the airport in Palm Springs, California, the main landing gear collapsed and the Cessna 177 skidded to a stop on the runway. The right stabilator sustained substantial damage.
A post-accident 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.
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 Identification: GAA16CA074
This November 2015 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.