Regulacje i polityka gospodarcza · 25/09/2002

Airworthiness Directives; Boeing Model 747 Series Airplanes

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 747 series airplanes. This proposal would require an initial inspection to identify all H-11 steel bolts on the outer chord of the body station (BS) 2360 aft pressure bulkhead between stringers 12L and 12R; follow- on repetitive inspections to identify all remaining H-11 steel bolts on the entire outer chord of the BS 2360 aft pressure bulkhead; and follow-on and corrective actions, if necessary. This proposal also would require eventual replacement of all H-11 steel bolts with Inconel bolts. This action is necessary to prevent broken bolts, which could result in progressive failure of the remaining bolts and consequent structural damage and rapid depressurization of the airplane. This action is intended to address the identified unsafe condition.