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. BAe Systems (Operations) Jetstream 4100 Series Aeroplanes AD/J4100/26 Propellers - Propeller Speed 5/2009 Warning System - Installation Applicability: Jetstream Aircraft Ltd, British Aerospace Regional Aircraft Ltd, British Aerospace (Operations) Ltd and British Aerospace (Commercial Aircraft) Ltd Jetstream 4100 aircraft, all models, all serial numbers. Requirement: 1. Replace the existing Propeller Limitations Placard in the cockpit in accordance with BAE Systems (Operations) Ltd Service Bulletin (SB) J41-11-027 and ensure that the AFM contains General Amendment G12 and Advance Amendment Bulletin No. 13. 2. Install a Propeller Speed Warning System (modification JM41674) in accordance with Section 2 of BAE Systems (Operations) Ltd ACIB J41-61-014 and ensure that the AFM contains Particular Amendment P111. 3. Remove the placard and AFM Advance Amendment Bulletin No. 13 as introduced by Requirement 1 of this AD. The use of later approved revisions of the referenced documents is acceptable for compliance with the requirements of this AD. Note: EASA AD 2009-0038 dated 18 February 2009 refers. Compliance: For Requirement 1 - Within 30 days after the effective date of this AD, unless previously accomplished. For Requirement 2 - Within the next 6 months after the effective date of this AD. For Requirement 3 - After modification of an aircraft as Detailed in Requirement 2 of this AD. This Airworthiness Directive becomes effective on 7 May 2009. Background: During ground manoeuvring, prolonged operation with either engine in the restricted range between 82% and 90% RPM will result in damage to the propeller assembly that could eventually result in the release of a propeller blade. BAE Systems has now developed a Propeller Speed Warning System, embodiment of which will allow taxiing with the condition lever at TAXI, through the introduction of a revised Flight Manual Limitation. This AD requires the installation of a Propeller Speed Warning System. James Coyne Delegate of the Civil Aviation Safety Authority 27 March 2009