Overview

The Civil Aviation Regulations 1998 (Cth), specifically Part 39 - 105, introduced Airworthiness Directives to ensure the safety and airworthiness of aircraft. One such directive, AD/LEARJET 35/22, concerns the Gates Learjet 35 and 36 series aeroplanes, addressing the issue of insufficient aileron trim tab balance weight. This directive was enacted to mitigate the risk of flutter due to potential disconnects in the trim tab system, thereby preventing any adverse safety outcomes. The Civil Aviation Safety Authority, as the enacting body, aims to uphold stringent safety standards for all civil aviation operations within Australia. This legislative instrument underscores the importance of regular and mandatory modifications to critical aircraft components to ensure continued compliance with safety regulations and to protect the public from potential hazards.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, governs the airworthiness directives concerning various aircraft models, including the Gates Learjet 35 and 36 Series Aeroplanes. The directive AD/LEARJET 35/22 pertains to the replacement of the aileron trim tab balance weight for specific model Learjets identified by their serial numbers as listed in the Requirement Document. The directive mandates compliance within 600 hours of time in service after 31 December 1984 or upon the next aileron or trim tab removal or rebalance, whichever comes first. This regulation applies to all aircraft falling under the specified model and serial number criteria, aiming to address a design deficiency identified by the manufacturer that could potentially lead to aileron flutter due to inadequate balance weight. The directive references FAA AD 84-19-06 for additional context and ensures that all affected aircraft meet the necessary safety standards to prevent operational risks.

Key Provisions

The Civil Aviation Regulations 1998, under Part 39 - 105, establish specific Airworthiness Directives (AD) to ensure the safety of aircraft operations. Section AD/LEARJET 35/22 pertains to the replacement of the aileron trim tab balance weight for Gates Learjet 35 and 36 series aeroplanes. This directive applies to all model Learjets with serial numbers listed in the Requirement Document, specifically Gates Learjet AMK 83-3 (Section 1). The directive references FAA AD 84-19-06, issued on 12 December 1984, which highlights the necessity for this modification due to the identified insufficiency of the aileron trim tab balance weight in meeting failsafe design requirements. The objective is to prevent potential flutter if there is a disconnect in the trim tab system. Operators of Gates Learjet 35 and 36 series aeroplanes must comply with this directive by replacing the aileron trim tab balance weight within 600 hours of time in service after 31 December 1984, or at the next aileron/trim tab removal or rebalance, whichever comes first (Section 2). This requirement ensures that the aircraft maintain the necessary safety standards to prevent flutter, which could compromise the aircraft's stability and safety during flight. Failure to comply with the directive may result in serious safety implications. The Civil Aviation Safety Authority (CASA) enforces stringent measures to ensure adherence to AD/LEARJET 35/22. Non-compliance can lead to significant penalties, including fines and potential grounding of the aircraft until the required modifications are completed. In extreme cases, non-compliance might result in legal action against the operator, further underscoring the importance of adhering to these safety directives. The consequences of not addressing this directive can be severe, potentially leading to unsafe flight conditions and endangering lives.