COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Robinson R22 Series Helicopters AD/R22/46 MA-4-5 Carburettor 3/98 Applicability: All helicopters S/N 2571 through 2664 fitted with MA-4-5 carburettor and Carburettor Air Temperature (CAT) gauge P/N C604-6. Requirement: Unless previously carried out, replace the carburettor and CAT gauge in accordance with the requirements of Robinson R-22 Service Bulletin 82, dated 03 March 1997, and Robinson Helicopter Company Kit KI-114 Revision A, dated 6 March 1997. Note: FAA AD 97-25-05 Amdt 39-10228 refers. Compliance: Within 50 hours time in service from the effective date of this Directive. This directive become effective on the 26 February 1998. Background: Advice has been received that the mixture control could inadvertently be placed in the idle cut position during in-flight manual leaning of the fuel/air mixture. This would cause an engine in-flight shut down with subsequent loss of helicopter control. When the carburettor is changed a flight manual amendment will be required.