AD/B727/99 Amdt 4 - No. 3 Cargo Door Frame (Cth)

AIRWORTHINESS DIRECTIVE On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/B727/99 Amdt 3 and issues the following AD under subregulation 39.001(1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Boeing 727 Series Aeroplanes AD/B727/99 Amdt 4 No. 3 Cargo Door Frame 8/2006

Applicability: Model 727-200 series aircraft, equipped with a No. 3 cargo door; as identified in Boeing Alert Service Bulletin 727-53A0169 Revision 2, or later FAA approved revision. Requirement: Action in accordance with the technical requirements of FAA AD 2006-13-01 Amdt 39-14653. Compliance: As specified in the Requirement document, with a revised effective date of 3 August 2006. This Amendment becomes effective on 3 August 2006. Background: There have been several reports of fatigue cracks occurring in the forward frame and fuselage skin of the No. 3 cargo door cut-out. Undetected cracking could eventually lead to failure of the frame and skin, and consequent rapid decompression.

Amendment 3 increased the area to be inspected, introduced additional inspections of repaired frames, and provided an improved modification for crack free frames, which terminated the repetitive inspection requirement.

Amendment 4 is issued in response to a new FAA AD, which was prompted by additional reports of cracking in the forward frame of the No. 3 cargo door cut-out. This Directive reduces the compliance time for initial inspections, adds an optional method of inspection for both the initial and repetitive inspections, and introduces inspections of an additional area. Additionally, this Directive clarifies that the previously optional structural modification is now required by other rulemaking (90-06-09, AD/B727/118 Amdt 1).