COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Beechcraft 50 (Twin Bonanza) Series Aeroplanes AD/BEECH 50/15 Elevator Trim Tab Hinge Beam 12/65 Applicability: All models. Requirement: Visually inspect the elevator trim tab hinge beam (P/N 50/610000/94) for cracking in the flange and web. Compliance: At intervals not exceeding 250 hours' time in service.