Airworthiness Directives; Boeing Model 737-600, -700, and -800 Series Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 737-600, -700, and -800 series airplanes. This AD requires doing a general visual inspection for sealant at the interface of the upper spar fittings, strut side skins, and the fittings of the thrust reverser strut fairing on the engine struts; and applying an injection seal or silicone sponge rubber with fillet seal if necessary. This AD is prompted by a report that an injection seal in the engine strut area may not have been properly completed or installed during production. We are issuing this AD to prevent flammable fluid (such as fuel or hydraulic fluid) from leaking onto a hot engine exhaust nozzle or into the engine core fire zone, and consequently causing an uncontrolled fire or explosion.