COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace BAe 3100 (Jetstream) Series Aeroplanes AD/JETSTREAM/19 Cracking of MLG Cylinder Upper Attach Lug Applicability: As listed in the requirement document. Requirement: Action in accordance with British Aerospace SB 32-JA860812. Compliance: In accordance with the requirement document. 5/87 Background: During fatigue testing of the main landing gear a crack occurred in the cylinder near the upper toggle attachment lug.