Overview

The Airworthiness Directive F2006B08775, enacted in 2003, was introduced by the Civil Aviation Safety Authority (CASA) to address safety concerns identified with the main landing gear brace strut actuators in Eurocopter SA 360 and SA 365 (Dauphin) Series Helicopters. This directive was issued following an in-flight incident where a brace strut actuator failed due to severe corrosion of the nut securing the end-fitting to the actuator body. The policy objective of this AD is to mitigate the risk of similar incidents by mandating specific maintenance actions based on the aircraft's operational environment and the duration since the actuator's installation. This legislation aims to ensure the continued airworthiness of the specified helicopter models by requiring timely inspections and repairs of the landing gear brace strut actuators.

Scope and Application

This Airworthiness Directive issued by the Civil Aviation Safety Authority (CASA) applies specifically to Eurocopter SA 360 and SA 365 (Dauphin) Series helicopters, namely versions N, N1, N2, and N3, which are equipped with a particular type of main landing gear brace strut actuator, identified by the part number 19570-XXX. The directive is necessitated by a reported in-flight incident involving the failure of a brace strut actuator due to severe corrosion of the nut securing the end-fitting to the actuator body. The scope of the AD mandates corrective actions to address this safety concern, with specific timelines for compliance depending on the duration the actuators have been installed and the atmospheric conditions in which the aircraft have been operated. The directive sets out detailed requirements that align with the instructions provided in Eurocopter Alert Service Bulletin No. 32.00.10, and references the corresponding DGAC AD 2003-321(A). Compliance is jurisdictional within the Commonwealth of Australia, and the AD is effective from 10 September 2003.

Key Provisions

The Airworthiness Directive (AD) issued under subregulation 39.1(1) of the Civil Aviation Safety Regulations 1998 (CASR 1998) mandates specific actions to be taken for Eurocopter SA 365 (Dauphin) series helicopters, particularly those equipped with certain main landing gear brace strut actuators (section 1). The AD requires adherence to the instructions outlined in the requirement section, which stipulates that the action must be performed in the conditions and within the timeframes mentioned in the compliance section (section 2). The directive applies to model AS 365 helicopters, versions N, N1, N2, and N3, fitted with the specified main landing gear brace strut actuator P/N 19570-XXX (section 3). The AD necessitates compliance with paragraph 2.B of Eurocopter Alert Service Bulletin No. 32.00.10, which addresses the issue of severe corrosion of the nut securing the end-fitting to the actuator body, as evidenced by a reported in-flight incident (section 4). The compliance timelines are contingent upon the duration the actuator has been installed and the environmental conditions in which the aircraft has been operated. For instance, for actuators installed for more than six years in tropical, humid, or salt-laden atmospheric conditions, the action must be completed within 30 days of the effective date of the directive. For those installed for more than six years in normal climatic conditions or for more than four but less than six years in harsh conditions, the action must be taken within three months. Actuators installed for six years in normal conditions must be addressed upon reaching that duration, and those installed for four years in harsh conditions must be addressed upon reaching that duration (section 5). Additionally, any previously held spare actuators must be inspected before installation (section 6). Operators of the affected aircraft are required to follow the specified maintenance and inspection procedures to ensure the safety and airworthiness of the helicopters (section 7). The AD mandates timely and thorough compliance with the prescribed actions to mitigate the risk of in-flight incidents caused by the identified unsafe condition (section 8). Failure to comply with the AD may result in non-compliance with civil aviation safety regulations, potentially leading to enforcement actions by the Civil Aviation Safety Authority (CASA) (section 9). The specific penalties for non-compliance are not detailed in the AD but may include administrative, civil, or criminal penalties as outlined in the applicable aviation safety legislation (section 10).