AD/B767/239 Electrical Power Ground Brackets (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 767 Series Aeroplanes

AD/B767/239 Electrical Power Ground Brackets 5/2008

Applicability:	Model 767-200, -300, -300F and -400ER series aeroplanes, as identified in Boeing Alert Service Bulletin (ASB) 767-24A0162, dated 30 May 2006.
Requirement:	Rework the existing ground stud bracket of the transformer rectifier units(TRU)/main battery charger (MBC), measure the resistance and install a new ground stud bracket of the TRUs by doing all the applicable actions specified in the Accomplishment Instructions of ASB 767-24A0162.
Later revisions of the above SB, approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-04-12, are considered acceptable for compliance with the equivalent Requirements of this Directive.
Note:  FAA AD 2008-04-12 Amdt 39-15384 refers.
Compliance:	Within 36 months after the effective date of this Directive.
This Airworthiness Directive becomes effective on 8 May 2008.
Background:	The work required by this Directive complements that already accomplished in accordance with AD/B767/203 (FAA AD 2004-23-14).  The additional work is required to prevent depletion of the main battery while in flight, resulting from the loss of both TRUs and the MBC, together with consequent loss of all DC power.  This loss of power could impact the safe flight and landing of the aeroplane due to the loss of function or malfunction of essential/critical systems and displays in the cockpit.

David Punshon
Delegate of the Civil Aviation Safety Authority

7 March 2008