AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/ECUREUIL/59 Amdt 3 and issues the following 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.
Eurocopter AS 350 (Ecureuil) Series Helicopters
AD/ECUREUIL/59
Amdt 4
Tail Rotor Hub Pitch Change Bearings 13/2002
Applicability: AS 350 helicopters versions B, BA, B1, B2, B3, BB and D fitted with tail rotor pitch change plate, P/N’s 350A33-2004-00/-01/-02/-03/-05 or 350A33-2009-00/-01, and not incorporating Mod 076551 or Eurocopter AS 350 Service Bulletin No.
65.00.38R1.
Requirement: 1. Check the rotational torque of the tail rotor pitch change plate bearing in accordance with paragraph 2.B (1) of Eurocopter Alert Service Bulletin (ASB) No. 05.00.29 Revision 3.
2. Carry out the axial play, friction point and brinelling check in accordance with paragraph 2.B (2) of Eurocopter Alert Service Bulletin (ASB) No. 05.00.29 Revision 3.
3. Before installation of a spare pitch change plate assembly carry out the requirement s of paragraphs 2.B 1 and 2.B 2 of Eurocopter Alert Service Bulletin (ASB) No. 05.00.29 Revision 3.
4. Disposition of components subject to the inspections as required by Items 1 - 3 of this Directive shall be in accordance with paragraph 2.B 3 of Eurocopter Alert Service Bulletin (ASB) No. 05.00.29 Revision 3.
Note 1: DGAC AD 1999-085-076(A) R3 refers.
Note 2: Incorporation of Eurocopter Service Bulletin AS 350 65.00.38.P5 constitutes terminating action for this Directive.
Compliance: 1. Unless previously accomplished within 10 flying hours after 31 October 2002.
2. At intervals not to exceed 50 flying hours from the previous check (without exceeding 6 months between two checks).
3. Prior to installation of a tail rotor pitch change plate assembly or a tail rotor gearbox assembly.
4. During compliance with Requirements 1, 2, or 3, as applicable.
The compliance times of Amendment 3 of this Directive remain unchanged by this issue.
Eurocopter AS 350 (Ecureuil) Series Helicopters
AD/ECUREUIL/59 (continued)
This Amendment becomes effective on 26 December 2002.
Background: In service reports have revealed deterioration of the tail rotor hub pitch change plate bearing which could have to the seizure of the bearing and loss of control of the aircraft. This Directive introduces measures to check for correct rotational torque, and regular maintenance checks to ensure the integrity of the assembly.
Amendment 1 was issued to correct Compliance Statement 2 to reflect the DGAC repetitive inspection requirements and to include the more stringent compliance requirements of DGAC 1999-085-076(A) R1 dated 14 May 1999.
Amendment 2 provides terminating action for this Directive and adds reference to disposition of components subject to the required inspections.
Amendment 2 of this Airworthiness Directive became effective on 15 June 2000.
Amendment 3 was been issued to reflect replacement of Eurocopter Service Bulletin No. 05.00.29 R2 with Eurocopter Alert Service Bulletin No. 05.00.29 Revision 3.
The Service Bulletin was updated to Alert status with no change to the technical content of the Service Bulletin.
Amendment 3 of this Airworthiness Directive became effective on 31 October 2002.
Amendment 4 of this Airworthiness Directive is raised to correct a typographical error in Amendment 3.
The original issue of this Airworthiness Directive became effective on 20 May 1999.
James Coyne
Delegate of the Civil Aviation Safety Authority 18 November 2002
The above AD is notified in the Commonwealth of Australia Gazette on 4 December 2002.
Overview
The Civil Aviation Safety Authority (CASA) issued Airworthiness Directive (AD) AD/ECUREUIL/59 Amdt 4 in 2002, revoking Amendment 3 of the directive and introducing measures to address the issue of deterioration in the tail rotor hub pitch change plate bearing of Eurocopter AS 350 (Ecureuil) Series Helicopters. This deterioration could lead to the seizure of the bearing, resulting in a loss of control of the aircraft. The AD mandates specific checks on the rotational torque and axial play of the tail rotor pitch change plate bearing, in accordance with Eurocopter Alert Service Bulletin (ASB) No. 05.00.29 Revision 3. Additionally, it requires the implementation of these checks at specified intervals, prior to the installation of new assemblies, and during compliance with other maintenance requirements. The policy objective behind this AD is to enhance aviation safety by ensuring the integrity and proper functioning of critical helicopter components, thus mitigating the risk of in-service failures.
Scope and Application
The Airworthiness Directive AD/ECUREUIL/59 Amdt 4 applies to specific versions of the Eurocopter AS 350 (Ecureuil) Series Helicopters, namely those fitted with tail rotor pitch change plate P/N’s 350A33-2004-00/-01/-02/-03/-05 or 350A33-2009-00/-01, and which do not incorporate modification 076551 or Eurocopter AS 350 Service Bulletin No. 65.00.38R1. This AD is issued under subregulation 39.1 (1) of the Civil Aviation Regulations 1998 (CAR 1998) and mandates specific actions to address an unsafe condition related to the tail rotor hub pitch change bearing. The requirements include checking the rotational torque, axial play, friction point, and brinelling of the bearing, as well as the disposition of components post-inspection, all in accordance with Eurocopter Alert Service Bulletin (ASB) No. 05.00.29 Revision 3. The directive stipulates compliance intervals and conditions, such as checks within 10 flying hours after 31 October 2002, at intervals not exceeding 50 flying hours, and before installing a new pitch change plate assembly. The AD is applicable across the Commonwealth of Australia and is notified in the Commonwealth of Australia Gazette.
Key Provisions
The main operative sections of this Airworthiness Directive (AD) concern the specific requirements and compliance times for inspections and actions related to the tail rotor hub pitch change bearings of certain Eurocopter AS 350 (Ecureuil) Series Helicopters (section 1). The directive mandates checks on the rotational torque of the tail rotor pitch change plate bearing (section 1(1)), axial play, friction point, and brinelling checks (section 1(2)), and pre-installation checks of spare pitch change plate assemblies (section 1(3)). It also stipulates the disposition of components following the inspections (section 1(4)). The applicability section (section 2) details which aircraft are subject to the directive, specifically those AS 350 helicopters fitted with certain tail rotor pitch change plate parts and not incorporating specific modifications. The compliance section (section 3) outlines the timing for these checks, including an initial check within 10 flying hours after 31 October 2002, subsequent checks at intervals not exceeding 50 flying hours or 6 months, and checks prior to the installation of a new tail rotor pitch change plate assembly or tail rotor gearbox assembly.
The obligations imposed by this AD require helicopter operators and maintainers to perform the specified inspections and checks as per the requirements outlined in the directive. These include ensuring the rotational torque and axial play are within acceptable limits, carrying out brinelling checks, and following the proper disposition of any components that do not meet the required standards. The directive also requires compliance with Eurocopter Alert Service Bulletin (ASB) No. 05.00.29 Revision 3 for the detailed inspection procedures. The AD applies to specific versions of the Eurocopter AS 350 series helicopters, and operators must ensure their aircraft meet the criteria listed in the applicability section to comply with the directive.
Failure to comply with the AD may result in serious safety risks, including the potential seizure of the tail rotor hub pitch change bearing, leading to a loss of control of the aircraft. While the AD itself does not explicitly state penalties for non-compliance, breaches of airworthiness directives can lead to enforcement actions under the Civil Aviation Regulations 1998 (CAR 1998). These may include administrative penalties, such as fines, and potentially more severe consequences if non-compliance results in an aircraft being operated in an unsafe condition. The exact penalties would be determined based on the specific circumstances of the non-compliance and any resulting safety incidents.