AD FAA-2010-0547

We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 757 airplanes. This AD was prompted by reports of fuel leaking from the front spar of the wing through the slat track housing. This AD requires a detailed inspection of the inboard and outboard main slat track downstop assemblies and a torque application to the main track downstop assembly nuts of slat numbers 1 through 10, excluding the outboard track of slats 1 and 10; a detailed inspection of all slat track housings for foreign object debris (FOD) and visible damage; and corrective actions if necessary. We are issuing this AD to detect and correct incorrectly installed main slat track downstop assemblies, which, when the slat is retracted, could cause a puncture in the slat track housing and lead to a fuel leak and potential fire.