COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Cessna 150, F150, 152 & F152 Series Aeroplanes AD/CESSNA 150/30 Amdt 1 Exhaust Heat Exchanger 3/79 Applicability: Models: 152 with S/Nos 15279406 to 15282919. A152 with S/No. A1520735 to A1520845, fitted with a KMR Industries P/N 1-1000 exhaust system, either bearing S/No. 1 to 3999 or having an "R" prefix or suffix on any Serial No. Requirement: Action in accordance with Cessna SL No. SE 78-71. Compliance: Before further flight after 22 January 1979 and thereafter at intervals not exceeding 50 hours time in service until paragraph "B" of Cessna SL No. SE 78-71 is complied with. Note: Compliance with the previous issue of this Directive does NOT constitute compliance with this issue of the Directive.