COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Bell Helicopter Textron 412 Series Helicopters AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (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/BELL 412/42 Main Hydraulic Servo Actuator Rod End Lock Washer 9/2001 DM Applicability: Model 412, 412EP and 412CF helicopters incorporating hydraulic servo actuator, part number 41000470, serial numbers with "HR' prefix up to and including 10010. Requirement: 1. Inspect the tab on the rod end locking washer of each hydraulic servo actuator for bending and twisting in accordance with "Accomplishment Instructions", Paragraph 2.A of Bell Helicopter Textron, Inc Service Bulletin 412-00-105 or 412CF-00-12, as applicable. 2. Replace P/No NAS513-6 lock washer with P/No NAS513K6C locking device in accordance with "Accomplishment Instructions", Paragraph 2.B of Bell Helicopter Textron, Inc Service Bulletin 412-00-105 or 412CF-00-12, as applicable. Note: FAA AD 2001-08-04 refers Compliance: 1. Within 25 flight hours after the effective date of this Airworthiness Directive. 2. Within 100 flight hours after the effective date of this Airworthiness Directive or at next actuator overhaul, whichever occurs first. This Airworthiness Directive becomes effective on 25 July 2001. Background: This Directive is prompted by reports of damaged main hydraulic actuator rod end lock washers which can result in rod end disengagement from the actuator and potential for loss of control of the main rotor. James Coyne Delegate of the Civil Aviation Safety Authority 18 July 2001 The above AD is notified in the Commonwealth of Australia Gazette on 25 July 2001.