AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/B767/89 and issues the following AD under subregulation 39.1 (1) of CAR 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/B767/89 Amdt 1 Thrust Reverser Control System Operational Checks 11/2002 Applicability: All Boeing 767 series aeroplanes powered by Pratt and Whitney JTD9D-7R4 series engines, or General Electric CF6-80A series engines, incorporating Boeing Service Bulletin 767-78-0061 Revision 4 or 767-78-0060 Revision 4 respectively. Requirement: 1. Carry out a functional test of the thrust reverser synch- lock system that satisfies the intent of the test specified in FAA AD 94-16-03 paragraph (e). 2. Repeat Requirement 1 functional test. 3. a. If any discrepancy is found during any functional test required by Requirement 1 or 2, correct the discrepancy in accordance with approved maintenance data; OR b. Operate the aeroplane in accordance with the conditions and limitations of the Minimum Equipment List (MEL), applicable to the registration mark of the aeroplane, provided the MEL only approves dispatch with: 1. no more than one thrust reverser on the aeroplane inoperative; and ii. no synch- lock on the aeroplane is in an unlocked position; and iii. the thrust reverser is deactivated in accordance with approved maintenance data. c. If the aeroplane is operated in accordance with Requirement 3 (b), correct the discrepancies found as required by Requirement 3(a). d. Repeat the functional test required by Requirement 1 or 2, as applicable, after correction of the discrepancies under Requirement 3(c). e. Carry out Requirement 3(a) if any functional test carried out under Requirement 3 (d) was unsuccessful. Note: FAA AD 94-16-03 Amdt 39-8993 refers and supersedes FAA AD 92-03-03. Boeing 767 Series Aeroplanes AD/B767/89 Amdt 1 (continued) Compliance: For Requirement 1: Unless previously accomplished, within 4000 hours time in service since installation of the thrust reverser synch-lock required by AD/B767/63 amdt 3, or within 4000 hours time in service from the last functional test of the synch- lock system, whichever occurs later. For Requirement 2: At intervals not exceeding 4000 hours time in service. For Requirement 3 (a) or (b): Prior to further flight. For Requirement 3 (c): Within 10 days after thrust reverser deactivation. For Requirement 3 (d) and (e): Prior to further flight. This Airworthiness Directive becomes effective on 31 October 2002. Background: This amendment to the Directive includes numerous editorial changes that include changes to the structure of the requirements and compliance sections. These changes have no affect on the original technical requirements of this Directive. However, it should be noted that the MEL relief provisions have been modified to better amplify the requirements in this regard. The repetitive function tests of the thrust reverser additional locking system required by this Directive was previously addressed by Requirement 3 of AD/B767/63 Amdt 2. This action separates the requirements for the thrust reverser in order to provide ease of maintenance control. The actions specified in this amendment, and the original Directive, are intended to prevent possible discrepancies in the thrust reverser system that can result in an inadvertent in- flight deployment. James Coyne Delegate of the Civil Aviation Safety Authority 30 August 2002 The above AD is notified in the Commonwealth of Australia Gazette on 9 October 2002.