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 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. Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters AD/BELL 206/156 Tail Rotor Blade 2/2005 TX Applicability: Model 206A, 206B, and 206L helicopters equipped with tail rotor blade part number 206-016-201-131, serial numbers CS-4820 through CS-4845. Requirement: Part A. Identification of Affected Tail Rotor Blades Verify if the aircraft is equipped with tail rotor blades identified in the "Blades Affected" section of Bell Helicopter Alert Service Bulletin (ASB) 206-04-101 or 206L-04-131, as applicable. If the aircraft is equipped with an affected blade, enter the part number and serial number into the technical record. If not equipped, indicate in the record that the aircraft is not equipped with blades affected by this Directive. Part B. Check for Tail Rotor Doubler De-bonding Until blade replacement, check the affected blades in accordance with Part I of ASB 206-04-101 or 206L-04-131, as applicable, or later Transport Canada approved revision. Part C. Replacement of the Blades Replace all affected blades in accordance with Part II of ASB 206-04-101 or 206L- 04-131, as applicable, or later Transport Canada approved revision. Note: Transport Canada AD CF-2004-25 refers. Compliance: For Part A: Before further flight after 30 December 2004. For Part B: Daily, until blade replacement. For Part C: Within 100 hours time in service after 30 December 2004, or before 31 January 2005, whichever occurs first. Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters AD/BELL 206/156 (continued) This Airworthiness Directive becomes effective on 30 December 2004. Background: An inadequate surface preparation on a limited number of blades resulted in two reported instances of blade root de-bonding. To ensure blade integrity, all suspected blades are to be checked daily until removed from service. James Coyne Delegate of the Civil Aviation Safety Authority 23 December 2004 The above AD is notified in the Commonwealth of Australia Gazette on 24 December 2004.