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 39.001(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. Propellers - Variable Pitch - Hamilton Standard AD/PHS/25 Propeller Blade Corrosion 8/2009 Applicability: Hamilton Sundstrand Propellers model 568F propellers with blades, part numbers (P/Ns) R815505R2, R815505R3, R815505R4, R815505S2, and R815505S3, that have a serial number (SN) listed in Table 1 of this AD, installed. Table 1 - Affected Propeller Blades by SN 31 259 1510 2299 2470 20010732 33 265 1515 2300 2473 20010917 34 277 1803 2383 2492 20020568 37 278 1813 2459 2510 40 403 1823 2460 2535 43 747 1834 2462 2577 105 1007 1917 2464 2625 230 1031 2072 2469 20010731 Note 1: These propellers are installed on, but not limited to, ATR-GIE Avions de Transport Regional ATR-42-400 and -500, ATR72-210A, -500, and Construcciones Aeronauticas, S.A. C-295 aeroplanes. Requirement: Remove from service blades, P/Ns R815505R2, R815505R3, R815505R4, R815505S2, and R815505S3 that have a SN listed in Table 1 of this AD. Note 2: FAA AD 2009-07-06 Amdt 39-15865 dated 20 March 2009 refers. Compliance: Within 30 days after the effective date of this AD, unless previously accomplished. This Airworthiness Directive becomes effective on 30 July 2009. Background: This AD results from reports of blades with corrosion pits in the tulip area of the blades. The issuing of this AD is intended to prevent cracks from developing in the tulip area of the blade, which could result in separation of the blade and loss of aeroplane control. James Coyne Delegate of the Civil Aviation Safety Authority 16 June 2009