Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 727 and 727C series airplanes. This proposal would require one-time inspections of the exterior body skin located at the forward corners of the mid-galley door hinge cutouts to detect cracking, and corrective actions, if necessary. This proposal also would require modification of the body skin of the mid-galley door hinge cutouts. This proposal is prompted by a report indicating that, during fatigue testing on a Boeing Model 727 series airplane, a crack was found in the body skin at the lower forward corners of the mid-galley door hinge cutouts due to cabin pressurization cycles. The actions specified by the proposed AD are intended to prevent such fatigue cracking of the body skin, which could result in reduced structural integrity of the fuselage and consequent loss of cabin pressurization.