COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Pilatus Britten-Norman BN-2 Series Aeroplanes AD/BN-2/15 Tail Plane Front Spar Attachment - Inspection NK Applicability: All models not incorporating Mod. No. NB/M/404. Document: Britten-Norman SB No. BN-2/SB.27. Compliance: Within 100 hours time in service after 29 May 1970 and thereafter at intervals not exceeding 100 hours time in service.