AD/B747/323 Amdt 1 Nose Wheel Well Top and Side Panel Webs and Stiffeners (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/B747/323 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 747 Series Aeroplanes

AD/B747/323 Amdt 1 Nose Wheel Well Top and Side
Panel Webs and Stiffeners 7/2005

Applicability:

All Model 747 series aircraft.

Requirement:

Action in accordance with the technical requirements of FAA AD 2005-09-02 Amdt 39-14070.

Note:  Boeing Alert Service Bulletins 747-53A2465 Revision 1, 747-53A2465 Revision 2, and 747-53A2465 Revision 4, or later FAA approved revisions, refer.

Compliance:

As specified in the Requirement document, with a revised effective date of 7 July 2005.

This Amendment becomes effective on 7 July 2005.

Background:

Fatigue cracks have been found in the nose wheel well side panel webs, top panel web, and side panel horizontal stiffener on seven aircraft with between 15,726 and 32,018 flight cycles.  In addition, a significant crack was found in the side panel web on Boeing’s 747-400 Fatigue Test Aircraft.

Amendment 1 is issued in response to a new FAA AD, which expands the area of inspection, adds a new secondary inspection if certain cracking is found, and reduces the intervals for the repetitive inspections.  The AD was prompted by a report of an in-flight decompression of a 747-100 series aircraft that had accumulated 27,241 total flight cycles.

David Villiers
Delegate of the Civil Aviation Safety Authority

26 May 2005