AD/B737/349 Windshield Wiper Motors (Cth)

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.

Boeing 737 Series Aeroplanes

AD/B737/349 Windshield Wiper Motors 1/2009

Applicability:	Model 737 aeroplanes as follows:
Model 737-400 and -500 series aeroplanes as identified in Boeing Alert Service Bulletin (ASB) 737-30A1059, dated 10 September 2007.
Model 737-600, -700, -700C, -800 and -900 series aeroplanes as identified in Boeing Service Bulletin (SB) 737-30A1057, Revision 1, dated 31 October 2007.
Requirement:	1.    Inspect to determine the part number and serial number of the windshield wiper motors for the pilot's and first officer's windshields, and do all applicable corrective actions, by accomplishing all of the applicable actions specified in the Accomplishment Instructions of ASB 737-30A1059, (for Model 737-400 and -500 series aeroplanes); or SB 737-30A1057, Revision 1 (for Model 737-600, -700, -700C, -800 and -900 series aeroplanes); as applicable.
A review of aeroplane maintenance records is acceptable in lieu of the Requirement 1 inspection if the part number and serial number of the windshield wiper motors can be conclusively determined from that review.
Following the inspection or records review, as applicable, for any windshield wiper motor that is found not to be affected by the requirements of this Directive, re-identifying the part number is not required.
Note 1:  ASB 737-30A1059 and SB 737-30A1057, Revision 1, refer to Rosemount Aerospace SB 2313M-347/2313M-348-30-01, dated 30 June 2006, as an additional source of service information for determining whether the windshield wiper motor (identified in the Rosemount SB as the "power module'') has been previously replaced and for changing the part number.
Note 2:  Appendix A of SB 2313M-347/2313M-348-30-01 identifies an incorrect serial number for Model Number 2313M-348-3.  Serial number M252 should be M0252.
Note 3:  SB 2313M-347/2313M- 348-30-01 specifies marking affected parts with an approved opaque material per BAC5307, classification RO, with an approved permanent marking material; however, for the purposes of this Directive, any permanent method of part marking is acceptable.

For Model 737-400, -500, -600, -700 and -800 series aeroplanes:  Accomplishing the modification of the wiring to the windshield wiper motors required by AD/B737/218 (paragraph (b) of FAA AD 2003-20-13) is acceptable for compliance with the Requirement 1 of this Directive, provided that no Rosemount Aerospace windshield wiper motor having part number (P/N) 2313M-347-3 or P/N 2313M-348-3 (P/N 2313M347-3 or P/N 2313M348-3) has been installed.
For Model 737-600, -700, -700C, -800 and -900 series aeroplanes:  Actions accomplished before the effective date of this Directive in accordance with ASB 737-30A1057, dated 6 October 2006, are acceptable for compliance with the Requirement 1; provided that the wiper motor serial number was legible for inspection purposes and the operational test specified in Step 3 in Work Packages 2 and 3 of the Accomplishment Instructions of ASB 737-30A1057, Revision 1, was completed.
2.    Rosemount Aerospace windshield wiper motors having P/N 2313M-347-3 or P/N 2313M-348-3 (P/N 2313M347-3 or P/N 2313M348-3) may not be installed on any aeroplane as a replacement spare.
Later revisions of the above SB(s), approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-24-05, are considered acceptable for compliance with the equivalent Requirements of this Directive.
Note 4:  FAA AD 2008-24-05 Amdt 39-15745 refers.
Compliance:	For Requirement 1 - Within 60 months after the effective date of this Directive.
For Requirement 2 - As of the effective date of this Directive.
This Airworthiness Directive becomes effective on 15 January 2009.
Background:	This Directive requires an inspection to determine the part and serial numbers of the windshield wiper motors for the pilot's and first officer's windshields together with the accomplishing of applicable corrective actions.  This Directive results from two reports that the left and right windshield wipers stopped working in flight.  The Directive is issued to prevent failure of the windshield wipers in wet weather, which could result in decreased visibility for the flightcrew.

James Coyne
Delegate of the Civil Aviation Safety Authority

27 November 2008