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/B747/338 Station 488 Frame Web 2/2006 Applicability: Model 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, 747SR, and 747SP series aircraft; as listed in Boeing Alert Service Bulletin 747-53A2508 original issue, dated 19 August 2004, or later FAA approved revision. Requirement: Action in accordance with the technical requirements of FAA AD 2005-22-06 Amdt 39-14350. Compliance: As specified in the Requirement document, with a revised effective date of 16 February 2006. This Airworthiness Directive becomes effective on 16 February 2006. Background: The FAA received reports of cracking at the upper aft corner of the cutout for main entry door number 1 in the station 488 frame web. Undetected cracking could result in failure of the frame and lead to rapid decompression of the aircraft. David Villiers Delegate of the Civil Aviation Safety Authority 21 December 2005