COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Cessna 210 Series Aeroplanes AD/CESSNA 210/50 Amdt 1 Engine and Turbocharger Installation - Checks and Modification 10/81 Applicability: Model P210N series with S/Nos. P21000001 to P21000690 not incorporating Cessna Service Kit No. SK210-98B. Document: 1. CESSNA SIL No. SE 81-35 and Supplement No. 1 or 2. FAA AD 81-15-05, Amendment No. 39-4168. Compliance: Within 200 hours time in service after 31 October, 1981. Background: This directive was originally issued to reduce the possibility of engine overheating and detonation caused by excessively lean mixtures during high power operation. It has been amended to increase the range of serial numbers of affected aircraft and to further reduce the possibility of detonation by additional modifications. Climb performance is also improved as the result of these modifications.