Transport i lotnictwo · 31.10.1996

Airworthiness Directives; Jetstream Model 4101 Airplanes

This document revises an earlier proposed airworthiness directive (AD), applicable to certain Jetstream Model 4101 series airplanes, that would have required a high frequency eddy current (HFEC) inspection to detect cracks of the boundary angle and joint angle of the rear pressure bulkhead, and repair, if necessary. That action also proposed to require modification of the rear pressure bulkhead of the fuselage. That proposal was prompted by a report of fatigue cracking in the rear pressure bulkhead of the fuselage. This action revises the proposed rule by referencing a new service bulletin that includes new technical procedures for accomplishing the HFEC inspection, and removing airplanes having certain constructor numbers. The actions specified by this proposed AD are intended to prevent such fatigue cracking, which could result in reduced structural integrity of the fuselage and, consequently, lead to the rapid decompression of the pressurized area of the airplane.