Airworthiness Directives; Cessna Aircraft Company Model 172R Airplanes

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 97-12-06, which was sent previously to known U.S. owners and operators of certain Cessna Aircraft Company (Cessna) Model 172R airplanes. This AD requires checking the clearance between both the gascolator and cowling area and the tailpipe and cowling area, and modifying these areas immediately if any evidence of rubbing at either location is found or modifying the gascolator to cowling area within a certain time period if no evidence of rubbing at either location is found. This AD results from an occurrence of fuel loss on a Cessna Model 172R airplane, which was severe enough to force an emergency landing. Investigation of the occurrence reveals that the cowling knocked the gascolator drain valve off the gascolator. The actions specified by this AD are intended to prevent the cowling from rubbing against the gascolator drain valve or the tailpipe, which could result in fuel loss and engine stoppage.