COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Beechcraft 77 (Skipper) Series Aeroplanes AD/BEECH 77/2 Rudder and Rudder Trim Tab 4/80 Applicability: All model 77 with S/Nos. WA-1 to WA-76. Requirement: Action in accordance with Beechcraft SI No. 1116. Compliance: Within 25 hours' time in service after 11 march 1980. Background: There is a possibility of water accumulating in the rudder and/or trim tab.