COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Boeing 747 Series Aeroplanes AD/B747/218 Crew Rest Area Heat Exchanger 1/2000 Applicability: Model 747-400 series aircraft; as listed in Boeing Alert Service Bulletin 747- 53A2430. Requirement: Action in accordance with the technical requirements of FAA AD 99-22-09 Amdt 39- 11387. Compliance: As specified in the Requirement document with a revised effective date of 31 December 1999. This Airworthiness Directive becomes effective on 31 December 1999. Background: The FAA received a report of interference between insulation blankets adjacent to the heat exchangers and flight control cables. The actions required by this Directive are intended to prevent a reduction in maximum rudder and elevator surface deflection due to the separation of heat exchangers from the body frame, which could result in reduced control of the aircraft.