Event Description
During cruise flight, the pilot heard and felt a 'thud' and detected an odor of 'hydraulic fluid burning.' The pilot diverted to an airport for landing. Attempts to lower the landing gear using both normal and emergency procedures were unsuccessful. When the airplane touched down on the runway, the landing gear collapsed, and the airplane veered left and struck a taxiway light.
Examination Findings
Post-incident examination revealed that the landing gear would not function. The landing gear hydraulic system was found depleted of fluid, and a hydraulic line on the nose gear actuator was found separated from its swedge fitting. Examination of the line revealed no evidence of abnormal wear.
Previous Occurrences
A review of Service Difficulty Reports on file with the Federal Aviation Administration for Cessna 172RGs revealed one similar event reported in 2001 in which a hydraulic line on the nose gear actuator was found separated from its swedge fitting.