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 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. Boeing 737 Series Aeroplanes AD/B737/218 Windshield Wipers 13/2003 Applicability: Model 737-400 and -500 series aeroplanes, as listed in Boeing Alert Service Bulletin (ASB) 737-30A1052, dated 12 October 2000 and Model 737-600, -700 and -800 series aeroplanes, as listed in Boeing ASB 737-30A1049, dated 1 June 2000. Requirement: Either: Modify the wiring to the left and right windshield wiper motors in the flight compartment (including changing certain wire bundles, reducing the windshield wiper blade force to between 3.5 and 4.5 pounds, and doing an operational test of the windshield wiper system), in accordance with ASB 737-30A1052 (for Model 737-400 and -500 series aeroplanes); or ASB 737-30A1049 (for Model 737-600, -700 and -800 series aeroplanes); as applicable, or, For Model 737-600, -700, and -800 series aeroplanes - Replace the left and right windshield wiper motor/converters in the flight compartment (including increasing the blade force of the windshield wipers to between 6.5 and 7.5 pounds; and doing an operational test of the windshield wiper system), in accordance with Boeing Service Bulletin (SB) 737-30-1054, Revision 1, dated 6 March 2003. Replacement of the left and right windshield wiper motor/converters accomplished prior to the effective date of this Directive in accordance with SB 737-30-1054, dated 9 May 2002, is considered acceptable for compliance with this Directive. For Model 737-400 and -500 series aeroplanes equipped with brushless windshield wiper motor/converters - Replace the left and right windshield wiper motor/converters in the flight compartment (including increasing the blade force of the windshield wipers to between 6.5 and 7.5 pounds; and doing an operational test of the windshield wiper system), in accordance with Boeing SB 737-30-1055, Revision 1, dated 6 March 2003. Boeing 737 Series Aeroplanes AD/B737/218 (continued) Replacement of the left and right windshield wiper motor/converters accomplished prior to the effective date of this Directive in accordance with SB 737-30-1055, dated 14 November 2002, is considered acceptable for compliance with this Directive. Note: FAA AD 2003-20-13 Amdt 39-13331 refers. Compliance: Before 27 November 2006. This Airworthiness Directive becomes effective on 25 December 2003. Background: This Directive requires either modification of the wiring to the windshield wiper motors in the flight compartment or replacement of those windshield wiper motor/converters with new motor/converters. This action is necessary to prevent a reduction in flight crew visibility due to stalled wiper motors during heavy precipitation and a period of substantial crew workload, which could result in damage to the aeroplane structure together with injury to flight crew or passengers during final approach for landing. Jim Coyne Delegate of the Civil Aviation Safety Authority 14 November 2003 The above AD is notified in the Commonwealth of Australia Gazette on 3 December 2003.