COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Maule M-4 Series Aeroplanes AD/ML-M4/12 Bucket Seats Retention - Inspection 10/78 Applicability: All model M-4-180C with S/Nos. 3001C to 3004C; All model M-4-220C with S/Nos. 2044C to 2060C. Document: Maule SL No. 21. Compliance: Within 25 hours time in service after 20 September 1978.