AD/DHC-8/15 Amdt 3 - MLG Actuator Support Bracket and Bolts

Overview

The Civil Aviation Regulations 1998, specifically Part 39 - 105 concerning the Civil Aviation Safety Authority's Schedule of Airworthiness Directives, was enacted to ensure the safety and compliance of aircraft operating within Australia. This particular legislative instrument focuses on Bombardier (Boeing Canada/De Havilland) DHC-8 Series aeroplanes and outlines amendments to address specific safety concerns. This directive aims to mitigate the risk of in-flight hydraulic power loss due to the failure of the Main Landing Gear (MLG) retract actuator support bracket bolts, which was evidenced by an incident where such a failure resulted in damage to adjacent hydraulic lines. The compliance requirements detailed in the Amendment 3 mandate adherence to Transport Canada's AD CF-91-25R2 and include additional checks and tests to ensure the integrity of the affected components. The Civil Aviation (Safety) Regulations 1998 were enacted by the Parliament of Australia, aiming to maintain the highest safety standards in civil aviation. This legislative instrument reflects a collaborative approach, incorporating international safety directives to enhance the safety of aircraft operations within Australia. The policy objective is to prevent in-flight incidents by ensuring that aircraft meet stringent safety standards, thereby protecting both the crew and passengers.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, governs the airworthiness directives concerning the Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes, focusing on the maintenance of the MLG Actuator Support Bracket and Bolts as per Amendment 3. This legislation applies to DHC-8 Series 100 and 300 aircraft with serial numbers ranging from 3 to 400, excluding serial number 391. The regulation mandates compliance with the technical requirements outlined by Transport Canada AD CF-91-25R2 and references de Havilland Service Bulletins 8-54-27 and 8-54-34. Compliance with this directive is crucial to prevent incidents such as the in-flight hydraulic power loss caused by a failed MLG retract actuator support bracket bolt, which can lead to damage to adjacent hydraulic lines. The directive ensures the aircraft meet safety standards through specific actions, such as torque checks on the bolts and non-destructive testing of the support bracket if bolt looseness is detected, with an effective date for compliance set at 12 December 1995. This legislative instrument underscores the importance of ongoing safety inspections and corrective actions to maintain the airworthiness of affected aircraft within the Australian jurisdiction.

Key Provisions

The main operative sections of the Civil Aviation Regulations 1998, Part 39 - 105, pertaining to the Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes, are outlined in AD/DHC-8/15 Amendment 3. This amendment addresses the structural integrity of the Main Landing Gear (MLG) actuator support bracket and bolts. Specifically, section (1) identifies the applicability of the directive to DHC-8 Series 100 and 300 models with serial numbers 3 through 400, excluding serial number 391. Section (2) mandates compliance with the technical requirements set forth by Transport Canada AD CF-91-25R2, referencing de Havilland Service Bulletins 8-54-27 and 8-54-34. Section (3) provides details on the compliance timeline, with a revised compliance date of 12 December 1995 for certain aspects of the directive, while maintaining the previous compliance terms unless otherwise specified. The obligations imposed on the parties governed by this legislation include adhering to the specific technical requirements outlined in the Transport Canada directive. Operators of affected DHC-8 Series 100 and 300 aircraft must ensure that the MLG actuator support bracket and bolts are inspected and maintained according to the detailed specifications provided in the referenced service bulletins. This involves performing specific torque checks on the bolts, conducting non-destructive tests on the support bracket if bolt looseness is detected, and following the re-torque requirements for the retraction actuator fitting between 50 and 100 flights after implementing Modification 8/2049. Ensuring compliance with these technical standards is essential to maintain the airworthiness of the aircraft and prevent potential in-flight hydraulic failures. Failure to comply with the Civil Aviation Regulations 1998, Part 39 - 105, and the specific airworthiness directives for the DHC-8 Series aircraft, can result in significant legal consequences. Civil penalties may be imposed for non-compliance, including fines up to the maximum statutory limits, as well as potential criminal charges for more severe breaches. The severity of penalties depends on the extent of the non-compliance and the impact on aviation safety. Operators found in breach of these regulations risk not only financial penalties but also the suspension or revocation of their air operator certificate, which could lead to the grounding of the affected aircraft until compliance is achieved.