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/B747/315 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/B747/315 Amdt 1 Wing Landing Gear Outer Cylinder 3/2007 Applicability: 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 2007-01-10 Amdt 39-14882. Note: Boeing Service Bulletins 747-32-2472 original issue, and 747-32-2131 Revision 2; or a later revision approved by the FAA, refer. Compliance: As specified in the Requirement document, with a revised effective date of 15 March 2007. This Amendment becomes effective on 15 March 2007. Background: This Directive requires inspection to determine whether the outer cylinder of the wing landing gear has certain part numbers, and replacement of the outer cylinder of the wing landing gear with a new, improved, or reworked part, if necessary. Fracture of an affected outer cylinder of a wing landing gear could result in collapse of the landing gear. Amendment 1 is issued in response to a new FAA AD, which requires, for certain aircraft, an additional one-time inspection to determine whether the outer cylinder has a certain other part number. For those aircraft, this Directive also requires replacement of the outer cylinder with a reworked or new improved part; as a result of identification of an additional unsafe part. David Villiers Delegate of the Civil Aviation Safety Authority 1 February 2007