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/B717/18 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 717 Series Aeroplanes AD/B717/18 Amdt 1 Passenger Oxygen Release System 9/2009 Applicability: McDonnell Douglas Model 717-200 aeroplanes, as identified in Boeing Alert Service Bulletin (ASB) 717-35A0003, Revision 1, dated 7 June 2005. Requirement: Replace the relay in the passenger oxygen release system in the forward cabin with a new relay and test for proper operation in accordance with the Accomplishment Instructions of ASB 717-35A0003, Revision 1. Replacements and tests accomplished before the effective date of this Directive in accordance with ASB 717-35A0003, dated 19 November 2004, are acceptable for compliance with Directive. Later revisions of the ASB 717-35A0003, Revision 1, approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2005-16-08, are considered acceptable for compliance with the equivalent Requirements of this Directive. Modifying the aircraft in accordance with either Boeing Service Bulletin (SB) 717-35-0004 original issue dated 10 January 2006 or Revision 1, dated 3 May 2006, as applicable by aircraft group identified in the SB, is optional terminating action for the repetitive inspections. Note 1: SB 717-35-0004 Revision 1 requires more work to be accomplished on Group 2 and 3 aeroplanes. Note 2: FAA AD 2005-16-08 Amdt 39-14213 refers. Compliance: For Group 1 aeroplanes, as identified in the ASB - Within six months after the effective date of the original issue of this Directive and thereafter at intervals not to exceed 3,100 flight cycles, until the aircraft is modified in accordance with SB 717-35-0004 or Revision 1, as applicable. For Group 2 aeroplanes, as identified in the ASB - Before the accumulation of 3,100 total flight cycles, or within six months after the effective date of the original issue of this Directive, whichever is later, and thereafter at intervals not to exceed 3,100 flight cycles, until the aircraft is modified in accordance with SB 717-35-0004 or Revision 1, as applicable. This Amendment becomes effective on 27 August 2009. Background: The FAA has received reports of a failed relay in the passenger oxygen release system, which could result in the oxygen masks failing to deploy and deliver oxygen to the passengers in the event of a rapid decompression or cabin depressurization. The original issue of this Directive required the repetitive replacing and testing a relay in the passenger oxygen release system in the forward cabin. This Amendment continues the repetitive inspection requirements but introduces an optional termination action to the repetitive inspections. The original issue of this Directive became effective on 29 September 2005. James Coyne Delegate of the Civil Aviation Safety Authority 30 June 2009