COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 107 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Fuel Supply and Metering Equipment AD/FSM/30 Mixture Control Shaft Retention Screw 3/95 Applicability: Precision Airmotive Corporation Model HA-6 series carburettors as detailed in Precision Airmotive Corporation Mandatory Service Bulletin No. MSA-6. Requirement: Install retainer clip P/N 55-A239 in accordance with Precision Airmotive Corporation Mandatory Service Bulletin No. MSA-6 or Marvel Schebler Service Bulletin No. A1- 78. Note: FAA Airworthiness Directive 94-25-04 refers. Compliance: Effective 2 March 1995: Unless previously accomplished; prior to 31 December 1995. Background: This Directive has been issued to require the installation of a retainer clip to the mixture control assembly. The requirement follows advice that excessive wear on the mixture control shaft retention screw can result in the mixture shaft moving out of position and a resultant interruption to fuel flow.