COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Bell UH-1 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/UH-1/16 Main Rotor Mast P/N 204-011-450-001 & -005 10/2000 DM Applicability: Models UH-1A, UH-1B, UH-1E, UH-1F, UH-1H, UH-1L, UH-1P, and HH-1K, TH- 1F, TH-1L, and Southwest Florida Aviation SW204, SW204HP, SW205, and SW205A-1 helicopters with a main rotor mast assembly part number 204-011-450- 001 or -005 installed. Requirement: Remove the main rotor mast assembly from service. Replace with a serviceable mast assembly that is neither a 204-011-450-001 nor a -005. Note: FAA AD 2000-15-21 refers. Compliance: Within 25 hours time in service after 30 August 2000. This Airworthiness Directive becomes effective on 30 August 2000. Background: The FAA received a report of a BHTI-manufactured Model UH-1B accident that was attributed to fatigue failure of a thin-walled mast installed on the helicopter. Steve Swift Delegate of the Civil Aviation Safety Authority 24 August 2000 The above AD is notified in the Commonwealth of Australia Gazette on 30 August 2000.