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-2/52 Amdt 1 Elevator Mass Balance Weights 5/89 Applicability: All models that do not have modification NB/M/990 embodied. Requirement: Action in accordance with Pilatus Britten-Norman SB BN2/SB113 Issue 3. Compliance: Prior to the issue of the next Maintenance Release after 18 May 1989. Background: This amendment extends the applicability to aircraft manufactured after the issue of Issue 2 of the SB.