COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace (Scottish Aviation) Twin Pioneer Series Aeroplanes AD/SA-TP/18 Amdt 2 Applicability: All models. Bolts in Main Undercarriage, Wing Lift NK Struts and Tailplane Attachments Document: Scottish Aviation TNS No. 22, Issue 5. Compliance: As detailed in the requirement document.