Airworthiness Directives; Boeing Model 737-100, -200, -300, -400, and -500 Series Airplanes; and Model 727-100 and -200 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 737-100, -200, -300, -400, and -500 series airplanes; and Model 727-100 and -200 series airplanes. This amendment requires a one-time inspection to determine the presence and condition of the breather plug in each fuel tank boost pump; and either installation of a new plug or replacement of the boost pump with a new or serviceable pump, if necessary. This amendment is prompted by a report that breather plugs were missing from fuel tank boost pumps. The actions specified by this AD are intended to prevent possible ignition of fuel vapor in the fuel tank boost pump, which could result in a fuel tank explosion in the event of a boost pump internal failure.