AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/APU/17 and issues the following AD under subregulation 39.1 (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. Auxiliary Power Units AD/APU/17 Amdt 1 Saphir 20 Model 095 Female Quill Shaft Cycles Since New 1/2005 Applicability: Microturbo Auxiliary Power Unit (APU) Saphir 20, model 095, installed on Super Puma 332 L2 helicopters. Requirement: 1. Remove from service female quill shaft reference 095-40-193-01. 2. Do not install female quill shaft reference 095-40-193-01 that has accumulated 460 cycles since new (CSN) or more. Note 1: All Saphir 20 model 095 APUs are currently equipped with this female quill shaft. Note 2: DGAC Airworthiness Directive F-2004-177 R1 dated 24 November 2004 as approved by EASA reference 2004-11120 dated 17 November 2004 refers. Compliance: 1. Before accumulating 460 CSN. Female quill shafts that have accumulated 460 CSN or more on the effective date of this Directive are to be removed before 10 additional cycles. 2. As of the effective date of this Airworthiness Directive. This Amendment becomes effective on 20 January 2005. Background: A case of rupture of the female quill shaft, which links the accessory gearbox to the gas generator, was discovered in service. The rupture of the female quill shaft may result in generator over speed followed by an uncontained burst. This Airworthiness Directive is an interim measure to address an unsafe condition till determination of root causes of the failure of female quill shaft is made and final solution is found out. Auxiliary Power Units AD/APU/17 Amdt 1 (continued) Revision 1 of this AD reduces the applicability to Super Puma 332 L2 helicopters. The original issue of this AD became effective on 24 November 2004. James Coyne Delegate of the Civil Aviation Safety Authority 3 December 2004 The above AD is notified in the Commonwealth of Australia Gazette on 22 December 2004.