AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/AS 355/52 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. Eurocopter AS 355 (Twin Ecureuil) Series Helicopters AD/AS 355/52 Amdt 1 TR Head Pitch Change Plate Bearing Spacer 13/2004 Applicability: AS 355 helicopters, versions E, F, F1, F2 and N, fitted with the tail rotor pitch change rotating plates, all part numbers, on which Eurocopter modification (Mod) 07 6554 has not been embodied. This Airworthiness Directive (AD) does not apply to post-mod 076550 pitch change plate assembly part number 350A33-2030-00. Requirement: 1. Identify the position of the spacer and the tail rotor pitch change rotating plate as per provisions of paragraph 2.B.1 of Eurocopter AS355 Alert Service Bulletin (ASB) 05.00.33 R1 dated 15 March 2004 or later revision approved by DGAC / EASA. 2. a. Monitor position of the spacer and the tail rotor pitch change rotating plate for alignment as per provisions of paragraph 2.B.2 of ASB 05.00.33 R1 or later revision approved by DGAC / EASA. The inspection detailed in requirement 2 may be performed by the pilot-in- command, in which case, a certification is to be made by entering AD/AS 355/52 Amdt 1 against the daily inspection certification on the maintenance release. A copy of this directive and of the requirement document must be carried in the helicopter. 2. b. If the paint index marks are aligned, embody Mod 076550 as per the provisions of paragraph 2.B.3 of ASB 05.00.33 R1 or later revision approved by DGAC / EASA. 2. c. If the paint index marks are mis-aligned, embody Mod 076550 as per the provisions of paragraph 2.B.4 of ASB 05.00.33 R1 or later revision approved by DGAC / EASA. Note 1: DGAC Airworthiness Directive F-2000-223-059 R1 as approved by EASA reference number 2004-9370 dated 7 September 2004 refers. Eurocopter AS 355 (Twin Ecureuil) Series Helicopters AD/AS 355/52 Amdt 1 (continued) Compliance: 1. Unless previously accomplished, at the latest within 10 flying hours after the effective date of this AD. 2.a. Daily, after the last flight of the day. 2.b. Not later than the next "T" basic inspection. 2.c. With-in 25 flying hours from detection of the misalignment. Note 2: Compliance to the original issue of AD/AS 355/52 is an acceptable alternate to this amendment and no further action is required. This Amendment becomes effective on 23 December 2004. Background: This amendment of the Airworthiness Directive reflects changes in the document referred to, in the original issue of the AD, namely revision 1 of Eurocopter AS 355 ASB 05.00.33 and revision 1 of DGAC AD F-2000-223-059. The changes are in the effectivity list and there is no difference in the technical contents. There have been reports of rotation of the bearing spacers in AS355 tail rotor. Such rotation indicates that the inner bearing race may be rotating on its shaft. Rotation may cause excessive wear and cut the rotating plate, which will cause deterioration and loss of pitch control of the tail rotor. The original issue of the directive addressed unsafe condition caused by the loss of pitch control of the tail rotor. The original issue of this airworthiness directive became effective on 14 June 2000. James Coyne Delegate of the Civil Aviation Safety Authority 8 November 2004 The above AD is notified in the Commonwealth of Australia Gazette on 1 December 2004.