On March 18, 1989, a Cessna 177RG (registration N52634) was involved in an aviation accident near Rockford, IL. Investigators recorded the probable cause as: THE INADEQUATE SERVICING OF THE HYDRAULIC FLUID BY MAINTENANCE PERSONNEL AND THE PILOT'S FAILURE TO EXTEND THE LANDING GEAR MANUALLY. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During rollout of a full stop landing, the main landing gear collapsed. The hydraulic power pack unit had been recently replaced; this was the second flight and landing since replacement. The hydraulic reservoir was slightly less than half full. Gear operation could not be obtained in a functional test at that fluid level; normal function was restored after servicing to capacity.
Incident Description
During the rollout of a full stop landing, the main landing gear collapsed. The hydraulic power pack unit had been replaced recently. This was only the second flight and second landing since the replacement of the unit.
Hydraulic System Condition
The hydraulic reservoir was observed to be slightly less than half full. A functional test of the landing gear system with the fluid level at that state could not obtain gear operation. After the reservoir was serviced to its operating capacity, normal gear function was achieved.
Outcome
The collapse of the main landing gear occurred during the landing rollout. No further details on the extent of damage or any other consequences are available from the source.