COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES FLS Aerospace OA7 Optica Series Aeroplanes AD/OPTICA/1 Flying Control System Bellcrank Assemblies 2/94 Applicability: Model OA7 Optica aircraft up to and including constructors number OA7-021. Requirement: 1. Inspect in accordance with FLS Aerospace Service Bulletin B2/MSB/1. 2. Incorporate modification Kit Set B2/MKS/MSB/1 Note: UK CAA AD 015-08-93 refers. Compliance: 1. At or before the next 50 hour inspection after 3 February 1994, and thereafter at each 50 hour inspection until modification Kit Set B2/MKS/MSB/1 is incorporated. 2. Unless already accomplished, prior to 3 February 1995. Background: There have been several instances, after minimal system operation, of the failure of the bonding of the bearing shells to the space tubes used in the bellcrank assemblies. The bearing shells are then able to work free of the bushes at either end of the bellcranks.