COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 107 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Radio Communication and Navigation Equipment AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive AD/RAD/68 Amdt 2. AD/RAD/68 Amdt 2 Mode C Transponder Altitude Checks 6/2000 Requirement: CANCELLED. Background: This Directive was based on United States Federal Aviation Administration (FAA) AD 99-23-22R1. The FAA AD was rescinded with effect 20 April 2000 as the FAA has determined that repetitive tests are unnecessary and they increase component wear. 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.