COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Fokker F100 (F28 Mk 100) 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/F100/42 Landing Gear Locking Mechanism 6/2000 Applicability: Model F28 Mk 100 series aircraft. Requirement: Inspect the main landing gear downlock actuator in accordance with the Accomplishment Instructions in Fokker Service Bulletin SBF100-32-094 Revision 1. Note: RLD AD 94-163(A) refers. Compliance: Unless previously carried out, within 6 calendar months from the effective date of this Airworthiness Directive. This Airworthiness Directive becomes effective on 15 June 2000. Background: The manufacturer has advised that a Fokker 100 experienced a main undercarriage collapse during landing. Subsequent investigation confirmed that no undercarriage component had failed but extreme inward side-load conditions during the landing caused the lock toggle link to be pulled out of the overcentre position resulting in a main gear collapse. Eugene Paul Holzapfel Delegate of the Civil Aviation Safety Authority 2 May 2000 The above AD is notified in the Commonwealth of Australia Gazette on 17 May 2000.