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 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 747 Series Aeroplanes AD/B747/276 Thrust Reverser Modifications and Tests 7/2002 Applicability: Model 747-200 and 300 series aeroplanes powered by General Electric Model CF6- 80C2 series engines with Power Management Control engine controls. Requirement: 1. Install an actuation system lock bracket and fastening hardware to each thrust reverser in accordance with the Accomplishment Instructions of Lockheed Martin Service Bulletin 78-1007, Revision 1, dated 18 March, 1997, or Middle River Aircraft Systems Service Bulletin 78-1007, Revision 2, dated 10 March, 1998. 2. Install an actuation system lock (also called an electro- mechanical lock or electro-mechanical brake) on each thrust reverser in accordance with the Accomplishment Instructions of Lockheed Martin Service Bulletin 78-1020, Revision 2, dated 20 March, 1997, or Middle River Aircraft Systems Service Bulletin 78-1020, Revision 3, dated 16 March, 1998. 3. Carry out thrust reverser wiring modifications of the wings, strut, and fuselage, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-78-2144, Revision 1, dated 11 April, 1996. 4. Carry out a functional test to detect discrepancies of the centre drive unit (CDU) cone brake and actuation system lock on each thrust reverser, in accordance with Appendix 1 of FAA AD 2000-15-04 amendment 39-11833. 5. Correct any discrepancy detected when carrying out the requirements of Requirement 4, and repeat the functional test of that repair, in accordance with the procedures described in approved maintenance data. 6. Repeat Requirement 4 functional tests. Note: FAA AD 2000-15-04 amendment 39-11833 refers that supersedes FAA AD 99- 15-08 amendment 39-11227 that supersedes FAA AD 95-06-01 amendment 39-9171. Boeing 747 Series Aeroplanes AD/B747/276 (continued) Compliance: For Requirements 1, 2 and 3: Prior to issue of a Certificate of Airworthiness. For Requirement 4: Within 1,000 hours time- in-service after accomplishment of Requirement 1, 2 and 3. For Requirement 5: Prior to further flight. For Requirement 6: At intervals not exceeding 1,000 hours time- in-service. This Airworthiness Directive becomes effective on 11 July 2002. Background: This Directive has been prompted as a result of a safety review of the thrust reverser systems on B747 aeroplane, and requires installation of modifications and repetitive functiona l tests of the system to ensure the integrity of the fail- safe features of the thrust reverser system to prevent the possibility of inadvertent in- flight deployment. James Coyne Delegate of the Civil Aviation Safety Authority 3 June 2002 The above AD is notified in the Commonwealth of Australia Gazette on 19 June 2002.