COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Beechcraft 300 Series Aeroplanes AD/BEECH 300/2 Wing Fatigue Life Limitation 11/91 Applicability: All models. Requirement: For aircraft serial number FA-2 to FA-190 inclusive: (a) Modify the lower forward wing spar attachment fittings by installing Beech Kit No. 101-4050, and (b) Retire from service the wing centre and outer section main spar lower cap assemblies, including the attachment fittings. Note: FAA AD 91-12-10 and Section 4-00-00 of the Beech 300 Service Maintenance Manual refers. Compliance: For Requirement paragraph (a): For Model 300 LW aeroplanes, prior to exceeding 8300 hours component time in service; and for Model 300 aeroplanes, prior to exceeding 9000 hours component time in service. For Requirement paragraph (b): Before exceeding 15 000 hours component time in service. Background: This AD requires the installation of cold-expanded bushes into the wing attachment lugs, to improve their fatigue characteristics. The unmodified lugs failed well short of the interim 15 000 hour life when fatigue tested. Beech is conducting further tests on the modified lugs with a view to extending the fatigue life beyond 15 000 hours. This requirement is based upon a Country-of-Origin FAA Airworthiness Directive and fatigue tests carried out by the manufacturer.