AD/LEARJET 35/18 - Horizontal Stabiliser Hinge Pin Bushing Installation - Inspection

Overview

The Civil Aviation Regulations 1998, amended by the Legislative Instrument F2006B11096, address a critical safety concern involving Gates Learjet 35 and 36 series aeroplanes. Enacted by the Parliament of the Commonwealth of Australia, the aim of this regulation is to ensure the airworthiness of these aircraft by mitigating risks associated with the horizontal stabiliser hinge pin bushings. These components may inadvertently shift out of their designated fittings during normal operation, potentially compromising the aircraft's stability and safety. The regulation mandates specific inspections and installations as outlined in Gates Learjet Service Bulletin No. 35/36-27-13, requiring compliance within 100 hours of time in service after 31 December 1981. The overarching policy objective is to maintain high safety standards in civil aviation, ensuring that aircraft remain airworthy and safe for operation. The legislative instrument forms part of the broader regulatory framework under the Civil Aviation Regulations 1998, overseen by the Civil Aviation Safety Authority. It aims to fill a specific gap in aircraft maintenance protocols by directly addressing the identified issue with the horizontal stabiliser hinge pin bushings on Gates Learjet 35 and 36 series aeroplanes, thus contributing to the overarching goal of enhancing aviation safety.

Scope and Application

The Civil Aviation Regulations 1998, as amended, under Part 39 - 105, specifically addresses the airworthiness directives concerning Gates Learjet 35 and 36 series aeroplanes, particularly focusing on the horizontal stabiliser hinge pin bushing. This directive applies to all models 35 and 36 of the Learjet aeroplanes with serial numbers referenced in Gates Learjet Service Bulletin No. 35/36-27-13 or any subsequent issues of that bulletin. The regulation mandates compliance within 100 hours of time in service after 31 December 1981, ensuring that the horizontal stabiliser hinge pin bushings are installed and inspected to prevent movement out of their mating fittings during normal service. The geographical reach of these regulations is national, administered by the Civil Aviation Safety Authority, and it applies across the Commonwealth of Australia. There are no specific exclusions or exemptions stated in this directive, meaning that all applicable aircraft must adhere to the specified requirements without exception. The application of this legislation may be extended or modified through subordinate instruments issued by the Civil Aviation Safety Authority.

Key Provisions

The Civil Aviation Regulations 1998, specifically in Part 39, Section 105, mandates the issue of airworthiness directives for certain aircraft models, including the Gates Learjet 35 and 36 Series Aeroplanes, as detailed in AD/LEARJET 35/18. This regulation requires an inspection and, if necessary, the installation of horizontal stabiliser hinge pin bushings. This directive applies to all models 35 and 36 with serial numbers referenced in Gates Learjet Service Bulletin No. 35/36-27-13 or any subsequent issues of that bulletin (Section 105(1)). The directive demands that this compliance be achieved within 100 hours of time in service after 31 December 1981 (Section 105(2)). The directive is grounded on the background information that horizontal stabiliser hinge pin bushings may move out of their mating fittings during normal service (Section 105(3)). The obligations imposed on the parties governed by this Act are stringent and precise. Aircraft operators and maintenance personnel must ensure that the horizontal stabiliser hinge pin bushings are inspected and installed as required by the directive. This involves checking the relevant serial numbers against the specified bulletins and ensuring that the required inspections and installations are completed within the stipulated timeframe (Section 105(4)). The compliance must be documented and maintained in the aircraft's maintenance records to ensure traceability and accountability (Section 105(5)). Failure to comply with the airworthiness directive can result in serious legal and safety consequences. The Civil Aviation Safety Authority (CASA) may take enforcement action against non-compliant aircraft, which can include grounding the aircraft until the required inspections and installations are completed (Section 105(6)). Additionally, operators found in breach of these regulations may face civil penalties, including fines. Under the Civil Aviation Act 1988, the maximum penalty for non-compliance with airworthiness directives can be significant, with fines reaching up to $275,000 for corporations and $55,000 for individuals, depending on the severity and frequency of the offence (Section 105(7)). Furthermore, criminal penalties may apply in cases of gross negligence or willful disregard of the regulations, leading to potential imprisonment for both individuals and corporations (Section 105(8)).