Airworthiness Directives; Lockheed Model L-1011-385 Series Airplanes

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 98-08-09 that was sent previously to all known U.S. owners and operators of certain Lockheed Model L- 1011-385 series airplanes by individual notices. This AD requires revision of the Airplane Flight Manual (AFM) to prohibit operation of the fuel boost pumps when fuel quantities are below certain levels, and to add new maintenance procedures for operating the airplane with an inoperative fuel boost pump assembly or with an inoperative flight station fuel quantity indicating system. This AD also requires the installation of a placard on the engineer's fuel panel to advise the maintenance crew that operation of the fuel boost pumps when less than 1,200 pounds of fuel are in the corresponding wing fuel tank is prohibited. This action is prompted by reports of internal electrical failures in the fuel boost pump of the wing fuel tanks that could result in either electrical arcing or localized overheating. The actions specified by this AD are intended to prevent such electrical arcing or overheating, which could breech the protective housing of the fuel boost pump and expose it to fuel vapors and fumes, and consequent potential fire or explosion in the wing fuel tank.