AD/BEECH 90/51 - Elevator Control System - Inspection and Modification

Overview

The Civil Aviation Regulations 1998 (Cth) were enacted to regulate the safety and operational standards of civil aviation in Australia, addressing the need for a cohesive regulatory framework that ensures the safety of aircraft, passengers, and crew. This legislative instrument, specifically Part 39 - 105, focuses on the Civil Aviation Safety Authority’s Schedule of Airworthiness Directives, which mandates specific safety measures for particular aircraft models. In this instance, AD/BEECH 90/51 pertains to the Beechcraft 90 and 65-90 (King Air) series aeroplanes, aiming to prevent potential failures in the elevator control system. The policy objective is to ensure that the identified aircraft meet the required safety standards by conducting necessary inspections and modifications, thereby mitigating the risk of in-flight incidents. Compliance with these directives is mandatory, with specific deadlines set for the inspections and modifications to be completed.

Scope and Application

The Civil Aviation Regulations 1998, as amended, under Part 39 - 105 Civil Aviation Safety Authority, specifically within the Schedule of Airworthiness Directives, addresses the maintenance and safety requirements for Beechcraft 90 and 65-90 (King Air) series aeroplanes. This particular legislative instrument, AD/BEECH 90/51, is applicable to all models with serial numbers LJ-114 to LJ-705 and LW-1 to LW-141 equipped with a Beechcraft H-14 autopilot, except those that have incorporated Beech Mod. Kit No. 90-9067-15 or later approved revisions. The directive aims to prevent potential elevator cable failures by mandating a thorough inspection and, where necessary, modification of the elevator control system. Compliance with these regulations is mandatory before further flight and before a specified date of 1 September 1978, ensuring that all affected aircraft meet the outlined safety standards.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, mandate a series of safety directives for Beechcraft 90 and 65-90 (King Air) Series aeroplanes. The focus of these regulations is on the elevator control system, with the directive AD/BEECH 90/51 (section 1) providing detailed requirements for inspection and possible modifications (section 2). This directive applies to all models with serial numbers LJ-114 to LJ-705 and LW-1 to LW-141 equipped with a Beechcraft H-14 autopilot, excluding those that have already incorporated Beech Mod. Kit No. 90-9067-15 or later approved revisions (section 3). To ensure compliance, operators must perform a series of inspections and modifications on the elevator control system. Firstly, the aft fuselage belly access door must be opened to locate the autopilot elevator servo bellcrank at FS 319.00 (section 4). The length of the bellcrank is then measured; if it is 10 inches or less, no further action is required. However, if the bellcrank measures 13.5 inches or larger, a visual inspection of the primary elevator control cable, the pulley bracket at FS 340.00, the autopilot servo cable, and the autopilot bellcrank must be conducted to check for any signs of rubbing or damage (section 5). If rubbing is noted without damage, the autopilot servo cable should be disconnected and removed, and a placard indicating "Autopilot inoperative" should be installed in plain view of the pilot (section 6). If fraying or other damage is observed, the elevator cable must be replaced, any other damaged parts must be repaired or replaced, and the steps in section 6 must be followed (section 7). Additionally, if not previously completed, the servo mount of any H-14 elevator autopilot servo with a 13.5 inch or larger bellcrank must be modified in accordance with Beech Modification Kit No. 90-9067-15 or later approved revision, and the "Autopilot inoperative" placard should be removed (section 8). Operators are required to ensure these inspections and modifications are completed before any further flight and before 1 September 1978 (section 9). Failure to comply with these directives can result in safety risks, including the potential for elevator control failure, which could lead to serious accidents. Under the Civil Aviation Act 1988, any breaches of these regulations may result in significant penalties. For instance, serious breaches can lead to civil penalties of up to $1.65 million for corporations and $330,000 for individuals, as well as potential criminal charges. Operators found to be in breach of these directives may also face additional consequences such as grounding of the aircraft, revocation of airworthiness certificates, and legal action from affected parties.