Summary
We propose to adopt a new airworthiness directive (AD) for all Model 757 airplanes. This proposed AD would require changing the lower fixed leading edge panel assemblies immediately outboard of the nacelles at slats 4 and 7. This proposed AD results from reports of Model 757 airplanes in service that have drain holes and unsealed panel assemblies in the fixed leading edge adjacent to the inboard end of slats 4 and 7 that are too close to the hot portion of the engines. We are proposing this AD to prevent fuel leaking onto an engine and a consequent fire.