COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Pitts S-1 and S-2 Series Aeroplanes AD/PITTS S-2/2 Aileron Inter-Connect Tube - Modification 8/73 Applicability: Model S-2A with S/Nos. 2001 to 2025. Document: Pitts SB No. 5; Supplement No. 1. Compliance: Before 30 September 1973 unless already accomplished.