Summary
We propose to adopt a new airworthiness directive (AD) for certain Cessna Aircraft Company (Cessna) Models 172R and 172S. This proposed AD would require you to inspect the fuel return line assembly for chafing; replace the fuel return line assembly if chafing is found; and inspect the clearance between the fuel return line assembly and both the right steering tube assembly and the airplane structure, adjusting as necessary. This proposed AD results from reports of chafed fuel return line assemblies, which were caused by the fuel return line assembly rubbing against the right steering tube assembly during full rudder pedal actuation. We are proposing this AD to detect and correct chafing of the fuel return line assembly, which could result in fuel leaking under the floor and fuel vapors entering the cabin. This condition could lead to fire under the floor or in the cabin area.