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. Dornier 328 Series Aeroplanes AD/DO 328/4 De-icing/Anti-icing Fluids 1/2006 TX Applicability: Dornier 328-100 series aeroplanes. Requirement: Unless previously accomplished insert Dornier 328 All Operators Telefax No. AOT-328-00-022 Revision 1 dated 7 November 2003 or later LBA approved revision into the Aeroplane Flight Manual and advise the Flight Crew to operate the aeroplane accordingly until further notice. Note: LBA AD D-2004-007 EASA Approval No. 2004-48 dated 8 January 2004 refers. Compliance: Before further flight. This Airworthiness Directive becomes effective on 28 November 2005. Background: Testing of undiluted de/anti-icing fluids (Type II and IV fluids, based on propylene glycol) has shown that some of the fluid remains on wing, aileron and flap surfaces during the takeoff run, rotation and during initial climb out. This causes a temporary decrease in lift, increase in drag and can lead to reduced controllability of the aeroplane. James Coyne Delegate of the Civil Aviation Safety Authority 22 November 2005