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. Propellers – Variable Pitch - Hartzell AD/PHZL/73 Discrepant "Y" Shank Propellers 8/2001 Applicability: All Hartzell "Y" shank propellers, ( )HC-( )( )Y( )-( ) as listed by serial number in Table 1. The subject propellers were overhauled by Brothers Aero Service Company, Inc (BASCO) in the USA from November 1996 to October 1998 inclusive. Table 1 - Affected Hub Serial Numbers 121, 251, 715, 1111, 1387, 1661, 2383, 2479, 2883, 3059, 3343, 3479, 3717, 3890, 3990, 4690, and 5523 AM911 AN1309, AN2773, AN2826, AN2828, and AN3883 AU42, AU696, AU814, AU992, AU1226, AU1290, AU1416, AU2641, AU2643, AU2658, AU2699, AU2847, AU7186E, AU8364A, AU8418A and AU12997 BP344, BP715, BP1276, BP1772, BP2121, BP3811, BP3763, BP3978, BP5674, BP6126, BP6194, BP7141, BP7297, BP7513, BP8199, BP8708, and BP9586 CH6190 & CH19251 CJ52, CJ54, CJ419, and CJ649 DA1404 and DA1418 DG101 DJ4431, DJ4449, DJ9521A, DJ10407A, DJ11249A, DJ11880A, and DJ11881A DN3775 DV11 and DV12 FH307 P560 Requirement: If an affected propeller is installed and it has not been overhauled since 1 November 1998, replace it with a serviceable propeller of the same type, or overhaul it in accordance with manufacturer's approved maintenance data, or inspect the propeller in accordance with FAA AD 2001-07-03, Required Actions. Note: FAA AD 2001-07-03(Corrected) refers. Propellers – Variable Pitch - Hartzell AD/PHZL/73 (Continued) Compliance: Within 10 flying hours after the effective date of this Airworthiness Directive. This Airworthiness Directive becomes effective on 9 August 2001. Background: This AD is prompted by advice from the FAA that a US repair organisation released a number of discrepant Hartzell "Y" shank propellers into service. The discrepancies identified by the FAA could lead to propeller failure and subsequent loss of an aircraft. The action prescribed in this AD will ensure no discrepant propellers remain in service on Australian registered aircraft. Eugene Paul Holzapfel Delegate of the Civil Aviation Safety Authority 2 July 2001 The above AD is notified in the Commonwealth of Australia Gazette on 11 July 2001.