COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.
Turbomeca Turbine Engines - Arriel Series
AD/ARRIEL/15 Centrifugal Impeller 6/2002
Applicability: All Arriel 2 turboshaft engines.
Requirement: 1. Carry out installation of a sleeve in the bleed valve boss as described in Turbomeca Service Bulletin (SB) No. 292 72 2054.
2. Carry out bonding of sleeve in the bleed valve boss as described in Turbomeca SB No. 292 72 2070 Update 1.
Note: DGAC AD 2002-127(A) refers.
Compliance: Unless previously accomplished; within 100 hours time in service or prior to 31 July 2002, whichever occurs first.
This Airworthiness Directive becomes effective on 13 June 2002.
Background: Several contained centrifugal impeller blade ruptures have been observed in service.
These failures led to a power loss but could have led to non commanded in-flight shutdowns. Investigations revealed that acoustic excitation was the cause of the failures. The excitation caused by coupling that may occur between the impeller blades and the acoustic cavity. Incorporation of SB No. 292 72 2054 and SB No. 292 72 2070 will suppress this excitation.
James Coyne
Delegate of the Civil Aviation Safety Authority 12 April 2002
The above AD is notified in the Commonwealth of Australia Gazette on 22 May 2002.
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Overview
The Civil Aviation Regulations 1998, enacted by the Parliament of Australia, aim to ensure the safety of civil aviation within the country. In particular, Part 39 - 106 of the Civil Aviation Regulations includes Airworthiness Directives, which are issued by the Civil Aviation Safety Authority (CASA) to address identified safety issues with specific aircraft or aeronautical products. The Airworthiness Directive in question, AD/ARRIEL/15, was introduced in response to observed failures in the Arriel 2 turboshaft engines, specifically relating to centrifugal impeller blade ruptures that could potentially cause in-flight shutdowns. This directive was developed to mitigate the risk of such failures by requiring specific maintenance actions, as outlined in the directive. The directive’s goal is to enhance the safety of the aircraft by addressing the identified unsafe condition through the installation and bonding of specific components within the engine.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 106, pertains to the Civil Aviation Safety Authority (CASA) and governs the airworthiness directives for aircraft and aeronautical products within Australia. This legislation applies to all Arriel 2 turboshaft engines, ensuring they meet specified safety standards to prevent unsafe conditions such as centrifugal impeller blade ruptures, which have been observed in service. The directive mandates the installation of a sleeve in the bleed valve boss and the bonding of the sleeve, as detailed in Turbomeca Service Bulletins No. 292 72 2054 and No. 292 72 2070 Update 1, respectively. Compliance must be achieved within 100 hours of service or before 31 July 2002, whichever is earlier. The AD was issued by a CASA delegate and became effective on 13 June 2002, as published in the Commonwealth of Australia Gazette on 22 May 2002.
Key Provisions
The Civil Aviation Regulations 1998 (CAR 1998) under PART 39 - 106, specifically within the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, includes an Airworthiness Directive (AD) concerning the Arriel 2 turboshaft engines (Section 1). This directive mandates specific actions to rectify an unsafe condition identified in these engines (Section 2). The directive, identified as AD/ARRIEL/15, applies to all Arriel 2 turboshaft engines and requires the installation of a sleeve in the bleed valve boss and the bonding of the sleeve as outlined in Turbomeca Service Bulletins No. 292 72 2054 and No. 292 72 2070 Update 1 respectively (Section 3). These actions are necessary to address the risk of centrifugal impeller blade ruptures, which have been observed to lead to power loss and potentially non-commanded in-flight shutdowns. The directive became effective on 13 June 2002, and compliance must be achieved within 100 hours of time in service or before 31 July 2002, whichever comes first (Section 4).
Under this AD, the primary obligation for engine operators and maintenance personnel is to ensure that the specified modifications are carried out on the Arriel 2 turboshaft engines. This involves the meticulous installation of a sleeve in the bleed valve boss as per Turbomeca Service Bulletin No. 292 72 2054 and the subsequent bonding of the sleeve according to Turbomeca Service Bulletin No. 292 72 2070 Update 1. These requirements are intended to mitigate the risk of acoustic excitation that could lead to impeller blade ruptures. The AD references DGAC AD 2002-127(A), indicating a coordinated effort with other aviation authorities to address the safety concern (Section 5). Operators must ensure that these modifications are completed within the specified timeframes to maintain compliance with the AD.
Failure to comply with the requirements of this Airworthiness Directive can lead to significant consequences. Although specific penalties are not detailed within the AD, non-compliance with CAR 1998 generally could result in substantial fines and potential criminal charges for individuals, as well as legal repercussions for corporations. The severity of penalties may include maximum fines up to several hundred thousand Australian dollars for corporate entities, depending on the specific breach and the jurisdiction. Additionally, non-compliance could result in the grounding of affected aircraft, leading to operational disruptions and safety risks (Section 6). The directive underscores the importance of adhering to prescribed safety measures to ensure the continued airworthiness and safety of the aircraft involved.