AD/HS 125/130 Amdt 1 - Engine and Flight Data Monitoring

Overview

The Civil Aviation Regulations 1998, enacted by the Commonwealth of Australia, include specific directives to ensure the safety of civil aviation, particularly within Part 39 - 105. One such directive, AD/HS 125/130 Amendment 1, targets the British Aerospace BAe 125 Series Aeroplanes equipped with certain AlliedSignal TFE731-3 series engines. The primary objective of this legislation is to mitigate the risk of uncontained engine failures, which have been identified as a significant safety hazard. The policy objective is to mandate specific modifications to the Airplane Flight Manual and enforce rigorous monitoring and maintenance protocols to enhance the safety standards of these aircraft, ensuring compliance with international standards and mitigating potential catastrophic outcomes. The directive was issued by the Civil Aviation Safety Authority and came into effect on 14 September 1994. It was introduced to address incidents of uncontained failure in the low pressure turbine discs of AlliedSignal TFE731-3 engines, which posed severe risks to flight safety. The regulation requires amendments to the Airplane Flight Manual to incorporate stricter limitations and monitoring requirements as outlined by the Federal Aviation Administration's Airworthiness Directive 94-07-03. This includes specific actions for calculating data and taking corrective measures based on FAA AD 94-07-03, as well as compliance with the Civil Aviation Order 106, which provides a terminating action for the requirements set forth in this directive.

Scope and Application

The Civil Aviation Safety Authority (CASA) regulations, specifically Part 39 - 105 of the Civil Aviation Regulations 1998, pertain to the airworthiness directives for British Aerospace BAe 125 Series Aeroplanes. This legislation applies to BAe 125 series aircraft equipped with AlliedSignal TFE731-3 series engines that do not incorporate the AlliedSignal Service Bulletin TFE731-72-3502. The regulation requires specific amendments to the Airplane Flight Manual (AFM) to align with the Federal Aviation Administration (FAA) Airworthiness Directive (AD) 94-07-03, which mandates changes to the Limitation Section of the AFM, calculation of recorded data, and specific actions post engine shut down. Compliance with these directives is mandatory for the continued airworthiness of the specified aircraft. The directive became effective on 14 September 1994 and requires compliance before further flight unless the specified actions have already been completed. The regulation's jurisdictional reach is national, as it is a Commonwealth instrument, applying uniformly across Australia. There are no stated exclusions or exemptions in the directive itself, but the applicability is limited to the specified aircraft and engine configurations. Subordinate instruments may further extend or clarify the application of this directive.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, includes the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives. This regulation details the requirements for ensuring the airworthiness of British Aerospace BAe 125 series aeroplanes fitted with AlliedSignal TFE731-3 series engines that do not incorporate the AlliedSignal Service Bulletin TFE731-72-3502 (Section 1). The directive mandates several actions to maintain the airworthiness of these aircraft, including amending the Airplane Flight Manual (AFM) to reflect certain requirements from the Federal Aviation Administration (FAA) Airworthiness Directive (AD) 94-07-03, as well as calculating and taking specific actions regarding engine data and monitoring (Section 1). The obligations under this directive are clear and detailed. Operators of BAe 125 series aircraft with the specified engines must amend their AFM by incorporating the FAA AD 94-07-03 amendments, specifically paragraphs (a), (1), (2), (3), and (4), and insert AFM amendment A/125-700B/12 (Section 1.1). Furthermore, operators must calculate data recorded in accordance with FAA AD 94-07-03, paragraph (b), (1), and take specific actions as outlined in FAA AD 94-07-03, paragraphs (b), (2), and (c) (Sections 1.2 to 1.4). These actions are crucial to ensure the safety and compliance of the aircraft with international airworthiness standards. Failure to comply with these requirements can result in serious consequences. Operators must ensure compliance with these directives effective from 14 September 1994, and any required actions must be completed before further flight (Section 1). The directive was initially issued in September 1992 in response to uncontained failures of the AlliedSignal TFE731-3 first stage low pressure turbine discs, and has since been amended to address additional safety concerns, including the need for low pressure rotor lock-up verification during engine start and detection of rubbing noises after engine shutdown (Section 2). The background information highlights the critical nature of these directives in preventing potential catastrophic failures and ensuring the safety of the aircraft and its occupants.