COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Bell Helicopter Textron Canada (BHTC) 222 Series Helicopters AD/BELL 222/4 Tail Rotor Servo Control Linkage 9/85 TX Applicability: All model 222 and 222U Helicopters. Requirement: Action in accordance with Bell Helicopter Textron Alert Service Bulletins 222-85-33 and 222U-85-8. Note: Copies of the requirement documents may be obtained from Department of Aviation Regional Offices. Compliance: Before further flight after 19 July 1985. Background: A 222 overseas while hovering experienced an uncontrollable right turn. The cause was found to be a disconnect of the control linkage on the tail rotor servo. A linkage rivet was missing which allowed the pivot pin to fall out.