AD/HS 748/15 - Nose Landing Gear Jack Support Beam

Overview

The Civil Aviation Regulations 1998, which were enacted by the Parliament of Australia, are designed to ensure the safety and regulation of civil aviation within the country. Specifically, Part 39 - 105 of these Regulations, which pertains to the Civil Aviation Safety Authority Schedule of Airworthiness Directives, addresses issues related to the airworthiness of aircraft through specific directives. One such directive, AD/HS 748/15, pertains to the British Aerospace (Hawker Siddeley) HS 748 Series Aeroplanes and mandates the retirement of the nose landing gear jack support beam for these aircraft. This directive was introduced to address the problem of cracks in the nose landing gear jack support beam, which, if left unaddressed, could potentially lead to failure of the nose landing gear. The policy objective of this directive is to enhance aviation safety by ensuring that all applicable aircraft meet the necessary safety standards before a specified number of landings. Compliance with this directive ensures that the risk of in-flight failure is mitigated, thereby protecting both passengers and crew.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, pertains to the Civil Aviation Safety Authority's schedule of airworthiness directives, which govern the safe operation of aircraft within Australia. The regulations apply to all HS748 aircraft pre-modification 1472, mandating the retirement of the Main Landing Gear Jack Support Beam P/N 48 D 11498 due to reported cracks that could potentially lead to the failure of the nose landing gear. This directive ensures that such aircraft comply with safety standards by retiring the specified beam before reaching a certain number of landings, depending on whether the aircraft is pre- or post-modification 684. The directive extends to aircraft recently imported into Australia and references UK regulations and British Aerospace service bulletins to ensure international compliance and safety standards are met. The scope of the legislation is geographically and operationally focused on ensuring the safety of aircraft within Australian airspace. It encompasses all relevant HS748 aircraft, mandating specific maintenance actions to prevent potential safety hazards. The application of the directive is contingent on the number of landings the aircraft has accumulated, with different thresholds for pre- and post-modification 684 aircraft. The directive does not specify any exclusions or exemptions, thereby applying uniformly to all affected aircraft. This regulation is part of a broader framework that may be extended or further defined through subordinate instruments, ensuring ongoing safety and compliance within the aviation sector.

Key Provisions

The Civil Aviation Regulations 1998, specifically under PART 39 - 105, issue an Airworthiness Directive (AD) concerning the British Aerospace (Hawker Siddeley) HS 748 Series Aeroplanes. The directive, AD/HS 748/15, addresses the nose landing gear jack support beam, identified as P/N 48 D 11498 (section 5/95). This directive applies to all HS 748 aircraft pre-modification 1472. The primary requirement is to retire the main landing gear jack support beam before reaching a specified number of landings, contingent on whether the aircraft has undergone modification 684. For aircraft pre-modification 684, retirement is mandated before 900 landings, whereas for those post-modification 684, the requirement is before 3000 landings. The directive references the CAA(UK) AD 004-02-89 and British Aerospace Mandatory Service Bulletin 53/55 for further details. Modification 1472, as embodied in Service Bulletin 53/28, nullifies the need for compliance with this AD. The obligations under this directive involve ensuring the aircraft's main landing gear jack support beam is retired within the stipulated landings, depending on whether the aircraft has been modified. Operators must track the number of landings to comply with the retirement requirements. They must also ensure that the modifications, if any, are correctly implemented, particularly modification 1472, which supersedes the need for compliance with this specific AD. Adherence to the referenced service bulletins and CAA(UK) directives is also mandatory, as they provide the technical and procedural guidance necessary for compliance. Breach of this directive could lead to serious safety implications, as cracks in the nose landing gear jack support beam could result in the inability to extend or retract the nose landing gear, potentially leading to accidents. Although the Civil Aviation Regulations 1998 do not specify explicit penalties for non-compliance with this directive, failure to adhere to airworthiness directives generally can result in severe consequences, including the grounding of the aircraft, administrative penalties, and potential criminal charges if the non-compliance leads to accidents or loss of life. Operators must, therefore, ensure strict compliance to avoid such dire outcomes.