Overview

The Civil Aviation Regulations 1998 (CAR 1998) are a key piece of Australian legislation governing civil aviation safety, enacted by the Commonwealth of Australia. One specific Airworthiness Directive issued under these regulations is AD/CL-600/57, which pertains to the Bombardier (Canadair) CL-600 (Challenger) Series Aeroplanes, particularly those equipped with a horizontal stabilizer trim actuator (HSTA). This directive was introduced to address safety concerns identified in the HSTA, specifically the need to prevent failure of key components through the implementation of a life limit. The directive was issued by the Civil Aviation Safety Authority (CASA) and became effective on 11 July 2002, aiming to ensure that aircraft maintain their airworthiness and safety standards by mandating specific maintenance actions. The policy objective is to mitigate the risk of unsafe conditions that could arise from the failure of the HSTA by requiring timely revisions to maintenance schedules and replacement of the actuators under specified conditions.

Scope and Application

The Civil Aviation Regulations 1998 (CAR 1998), specifically Part 39 - 105, under the authority of the Civil Aviation Safety Authority (CASA), encompasses Airworthiness Directives (AD) which are binding on the operators of certain aircraft within Australia. The particular AD/CL-600/57 pertains to Bombardier (Canadair) CL-600 (Challenger) Series Aeroplanes, more specifically the CL-600-2B19 Canadair Regional Jet (CRJ) aircraft that are equipped with a horizontal stabilizer trim actuator (HSTA) with either part number 601R92305-1 or 601R92305-3. This AD is intended to address safety concerns identified through endurance testing of the HSTA, which revealed a need for a life limit to prevent the failure of critical components within the actuator. The requirements outlined in the AD include revising the approved maintenance schedule to include Temporary Revision (TR) No. 2B-816 dated 28 November 2001 and replacing the horizontal stabilizer trim actuator under specified conditions. Compliance with these requirements must be achieved within stipulated timeframes, which vary depending on the operational hours of the HSTA. The directive applies nationally within Australia and is enforced by CASA, with its effective date being 11 July 2002.

Key Provisions

The Civil Aviation Regulations 1998, Part 39 – 105, presents a specific Airworthiness Directive (AD) for Bombardier (Canadair) CL-600 (Challenger) Series Aeroplanes. This directive, AD/CL-600/57, is concerned with the horizontal stabilizer trim actuator (HSTA) and its critical role in the safe operation of the aircraft. The directive applies to CL-600-2B19 Canadair Regional Jet (CRJ) aircraft fitted with either the horizontal stabilizer trim actuator Part Number (PN) 601R92305-1 or PN 601R92305-3. The AD mandates specific actions to rectify identified unsafe conditions related to the HSTA. The primary requirements outlined in the AD are twofold. Firstly, operators must revise their approved maintenance schedules to incorporate Temporary Revision (TR) No. 2B-816 dated 28 November 2001, which is found in Part 2 of the Maintenance Requirements Manual, Appendix B – Limitations. This revision is essential to ensure that the maintenance schedule aligns with the new safety measures. Secondly, the AD requires the replacement of the horizontal stabilizer trim actuator. This replacement is imperative to prevent the failure of key components within the HSTA, which has been identified through endurance testing. Compliance with the AD is governed by specific timelines. For the maintenance schedule update, compliance must be achieved within 14 days from the effective date of the directive, which is 11 July 2002. Regarding the replacement of the HSTA, operators must act before the actuator reaches 19,200 hours of time in service (TIS). For actuators exceeding this threshold and those expected to exceed it within 500 hours TIS from the effective date of the directive, the replacement must occur within 500 hours TIS. Failure to adhere to these requirements can result in significant safety risks and potential non-compliance with aviation regulations. Failure to comply with the provisions of this AD may lead to serious consequences. The AD is legally binding, and non-compliance can result in enforcement actions by the Civil Aviation Safety Authority (CASA). This can include directives to address the non-compliance, financial penalties, or even grounding of the aircraft until the required actions are completed. The severity of the penalties depends on the nature and extent of the non-compliance, but the overarching aim is to ensure the highest standards of aviation safety are maintained.