AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (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/B747/395 Fuselage Stringer 11 Longeron 10/2009 between Station 2598 to 2607 Applicability: All Model 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, -400, -400D, -400F, 747SR and 747SP series aircraft. Requirement: Action in accordance with the technical requirements of FAA AD 2009-12-08 Amdt 39-15931. Note: Boeing Service Bulletin 747-53A2703 Revision 1, or later FAA approved revision, refers. Compliance: As specified in the Requirement document, with a revised effective date of 24 September 2009. This Airworthiness Directive becomes effective on 24 September 2009. Background: The FAA received a report of a crack in the fuselage right-side Stringer 11 longeron horizontal flange, adjacent to the horizontal stabiliser pivot bulkhead, during a routine maintenance inspection. Such fatigue cracking, unless detected and corrected, could propagate and cause damage to the adjacent horizontal stabiliser pivot bulkhead. This damage could result in loss of structural integrity and consequent inability of the bulkhead to carry flight loads. David Villiers Delegate of the Civil Aviation Safety Authority 12 August 2009