Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 727-100, - 100C, and -200 series airplanes. For certain airplanes, this proposal would require a one-time inspection of certain fuselage circumferential skin joints to determine the type of fasteners installed, and replacement of any aluminum fasteners with steel fasteners, if necessary; or modification of certain fuselage circumferential skin joints; as applicable. For certain other airplanes, this proposal would also require repetitive inspections to detect corrosion, sealant deterioration, cracking, or disbonding; repair, if necessary; and modification of certain fuselage circumferential skin joints. This proposal is prompted by reports of corrosion between the body skins and cold-bonded doublers at the fuselage circumferential skin joints. The actions specified by the proposed AD are intended to prevent delamination of the cold-bonded doublers, which could result in corrosion of the body skins and doublers, and consequent reduced structural capability of the fuselage circumferential skin joints.