AD/B747/225 - Thrust Reverser Deactivation Pins (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES

Boeing 747 Series Aeroplanes

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.

AD/B747/225 Thrust Reverser Deactivation Pins 6/2000

Applicability: Model 747-400 series aircraft powered by PW4000 series engines.

Requirement: Replace the deactivation pin, pin bushing in the aft cascade mounting ring, and insert flange on each thrust reverser half with new improved components in accordance with Boeing Alert Service Bulletin 747-78A2165 Revision 1 dated May 13, 1999.

Note: FAA AD 99-26-02 Amdt 39-11462 refers.

Compliance: Unless previously carried out, within 18 months time in service from the effective date of this Airworthiness Directive.

This Airworthiness Directive becomes effective on 15 June 2000.

Background: Partial deployment of deactivated thrust reversers has occurred during landing. Actions mandated by this Directive are intended to prevent failure of the thrust reverser deactivation pins, which could result in an in-flight deployment of the thrust reverser. Should this occur controllability of the aircraft will be reduced.