COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Aermacchi - Lockheed AL 60 Series Aeroplanes AD/AL 60/11 Engine Mounting Plates - Inspection and Modification Applicability: All models not incorporating Modification MB-L-001. 2/75 Requirement: 1. Inspect the engine mounting plates for cracks using a Dye Penetrant Technique in accordance with Aermacchi Lockheed Service Bulletin No. SB-L-0003. 2. Modify the engine mounting plates in accordance with Aermacchi Lockheed Modification Bulletin No. MB-L-0001. Compliance: For para. 1 - Within 10 hours' time in service after 20 January 1975 and thereafter at intervals not exceeding 100 hours' time in service until modified. For para. 2 - Before achieving 1200 hours total time in service.