COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Agusta A109 Series Helicopters AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/A109/29 Amdt 1 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. AD/A109/29 Amdt 2 Main Rotor Blades Tip Cap 2/2001 DM Applicability: Model A109C helicopters equipped with main rotor blades part number 709-0103-01 (all dash numbers) with serial numbers up to and including 1428, preceded by code A5 or EM. Requirement: Inspect in accordance with Agusta Bollettino Tecnico 109-106 Revision B, dated 21 December 2000. Note: ENAC AD 2000-571 refers. Compliance: Within 10 hours' time in service after 10 January 2001, unless already accomplished. Thereafter at intervals not to exceed 25 hours' time in service. This amendment becomes effective on 10 January 2001. Background: The manufacturer received several reports of cracking of the main rotor blade tip cap leading edge which caused a subsequent increase in the level of vibration. An investigation revealed extensive areas of debonding of the tip cap honeycomb core, which caused a pulsating effect on the tip cap and subsequent cracking. Amendment 1 reflected the latest revision of the Requirement document. Amendment 2 is issued in response to a new ENAC AD which mandates Revision B of the Requirement document. Amendment 1 of this Airworthiness Directive became effective on 14 October 1998. The original issue of this Airworthiness Directive became effective on 14 August 1998. Eugene Paul Holzapfel Delegate of the Civil Aviation Safety Authority 4 January 2001 The above AD is notified in the Commonwealth of Australia Gazette on 10 January 2001.