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/59 Main Wing Lower Skin and Lower Front Spar Structure Applicability: All Jetstream Series 3100 aircraft. 9/93 Requirement: Action in accordance with British Aerospace Jetstream Mandatory Service Bulletin 57-JA 921203. Note: UK CAA AD 014-05-93 refers. Compliance: As specified in the Requirement Document, with a completion date of 19 February 1994 for Accomplishment Instructions Parts 1 and 2 of the Requirement Document. Background: Reports of exfoliation corrosion damage of the lower main skin at bolts which attach the skin to the front spar structure between Stations 36 and 40, LH and RH.