AD/B737/311 Amdt 1 Main Wheel Well Electrical Connectors and Receptacles (Cth)

AIRWORTHINESS DIRECTIVE

On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/B737/311 and issues the following 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/B737/311 Amdt 1 Main Wheel Well Electrical
Connectors and Receptacles 2/2008 DM

Applicability:	Model 737-600, -700, -700C, -800 and -900 series aircraft, as identified in Boeing Special Attention Service Bulletin (SASB) 737-24-1169 Revision 1, dated 6 August 2007.
Requirement:	Action in accordance with the technical requirements of FAA AD 2007-23-10 Amdt 39-15256.
Compliance:	As specified in the Requirement document, with a revised effective date of 17 January 2008.
This Amendment becomes effective on 17 January 2008.
Background:	This Directive requires a detailed inspection of electrical connectors installed in the main wheel well to ensure that fillet sealant is installed on the inboard and outboard sides of the receptacles at the disconnect brackets.  Missing sealant around the receptacles could possibly result in corrosion damage, which could cause the loss of sufficient electrical bonding between the connectors and the disconnect bracket.  The loss of electrical bonding could result in loss of the shielding that protects the wire bundles from Electromagnetic Interference (EMI) and High Intensity Radiated Field (HIRF).  The loss of EMI and HIRF protection at those receptacles could possibly cause multiple electrical systems failure.  Those failures could result in the loss of several critical control systems that are necessary for safe flight.  In addition, a lightening strike could cause arcing in the fuel tank.
This Amendment corrects a typographical error in the Compliance Statement by changing the date from 17 January 2007 to 17 January 2008 and limits the applicability to aircraft listed in Revision 1 of the Boeing SASB.
The original issue of this Directive became effective on 17 January 2008.

Charles Lenarcic
Delegate of the Civil Aviation Safety Authority

19 December 2007