AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/B727/97 Amdt 3 and issues the following AD under subregulation 39.1 (1) of CAR 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 727 Series Aeroplanes AD/B727/97 Amdt 4 Supplementary Structural Integrity 10/2002 Applicability: All Model 727 series aircraft. Requirement: Incorporate the requirements of Boeing 727 Supplemental Structural Inspection Document (SSID) No. D6-48040-1 Volumes 1 and 2, Revision H, dated June 1994, into the aircraft system of maintenance, and inspect in accordance with the technical requirements of FAA AD 98-11-03 R1 Amdt 39-10983. Compliance: As specified in the Requirement documents. Where there are differences between the FAA AD and Revision H of the SSID, the FAA AD prevails. This Amendment becomes effective on 3 October 2002. Background: The Supplemental Structural Inspection Document has been produced to ensure the continued structural integrity of older model 727 aircraft and, by follow- up action, maintain the continuing airworthiness of the Boeing 727 fleet. Amendment 2 reflected the revision status of the SSID. Amendment 3 expanded applicability and required additional and expanded inspections, and repair of cracked structure. Amendment 4 is issued in response to a revision of the related FAA AD which corrects the requirements of the current FAA AD by allowing operators not to change their programs if they determine that the existing inspections are effective for the new or affected SSI. Amendment 3 of this Airworthiness Directive became effective on 10 September 1998. Amendment 2 of this Airworthiness Directive became effective on 24 October 1985. Boeing 727 Series Aeroplanes AD/B727/97 Amdt 4 (continued) The original issue of this Airworthiness Directive became effective on 31 January 1984. David Alan Villiers Delegate of the Civil Aviation Safety Authority 22 August 2002 The above AD is notified in the Commonwealth of Australia Gazette on 11 September 2002.