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-2/49 Pilots Seat Backs - Inspection and Modification 7/84 Applicability: All models with individual pilots sliding seat units - P/N NBC-010-H-001 (LH) and P/N NBC-010-H-002 (RH) or NBC-012-H-001, not embodying mod. NB/M/1217. Document: Britten Norman SB No. BN2/SB163. Compliance: INSPECT: Prior to the issue of the next maintenance release after 31 July 1984 and thereafter at each issue of a new maintenance release. MODIFY: Before 30 November 1984. Background: Some individual seat units, installed in the flight compartment, have been affected by distortion and fracture at the attachment of the folding back to the seat frame.