COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace BAe 146 Series Aeroplanes AD/BAe 146/13 Additional Elevator Mass Balance 8/89 DM Applicability: Series 100, 100A, 200 and 200A with serial numbers listed in the Requirement Document. Requirement: Action in accordance with BAe S.B. 55-7-00955D. Compliance: Prior to 30 November 1989. Background: This modification introduces additional mass balance forward of the elevator hinge line to assist in damping control column oscillations.