COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Bell Helicopter Textron 47 (All Variants) Series Helicopters AD/BELL 47/77 Amdt 1 Tail Rotor Hub Bolts 10/86 Applicability: Models 47B, 47B3, 47D, 47D-1, 47G, 47G-2 and 47H-1. Document: Bell SB No. 47-76-1. Kawasaki-Bell S.B. No. KSB-Bell 341. Compliance: Before 1 March 1976. For Kawasaki-Bell: Prior to issue of Certificate of Airworthiness. Background: The existing tail rotor hub bolts have been subject to failure due to fatigue. This Directive has been amended to include Kawasaki- Bell Helicopters.