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 737 Series Aeroplanes AD/B737/353 Stringer Tie Clips 5/2009 DM Applicability: All Boeing Model 737-100, -200, -200C, -300, -400 and -500 series aircraft, as identified in Boeing special attention service bulletin 737-53-1268 dated 25 August 2006. Requirement: Action in accordance with the technical requirements of FAA AD 2009-04-15 Amdt 39-15821. Note: Boeing special attention service bulletin 737-53-1268, dated 25 August 2006, or later FAA approved revision, refers. Corrective actions (repairs or repeat inspections) that are approved on an FAA form 8100-9 and approved by the Manager, Seattle Aircraft Certification Office or delegate, as an Alternative Method of Compliance (AMOC) to the requirements of FAA AD 2009-04-15, or later revision, may be carried out without the need to obtain an exclusion from CASA from this Directive. Compliance: As specified in the requirement document. This Airworthiness Directive becomes effective on 2 April 2009. Background: This AD results from a report of several cracked stringer tie clips. The AD is issued to detect and correct multiple adjacent cracked stringer tie clips and damaged skin and frames, which could lead to the skin and frame structure developing cracks, with subsequent structural failure and decompression. David Villiers Delegate of the Civil Aviation Safety Authority 10 March 2009