AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/EC 135/5 Amdt 2 and issues the following AD under subregulation 39.1 (1) of CASR 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 EC 135 Series Helicopters
AD/EC 135/5
Amdt 3
Main Rotor Drive Torque Struts 10/2003 DM
Applicability: All Model EC135 helicopters.
Requirement: Action in accordance with Eurocopter Deutschland Alert Service Bulletin ECD 135- 63A-002 Revision 4.
Note 1: Installation of titanium torque struts constitutes terminating action for the Requirements of this Directive.
Note 2: LBA AD 2001-107/3 refers.
Compliance: 1. As of the effective date of this Directive, a life limit of 500 flight hours applies for aluminium torque struts.
2. Aluminium torque struts that have exceeded the 500 flight hour life limit at the effective date of this Directive, are to be replaced with new torque struts within 100 flight hours after 13 August 2003, unless already accomplished. If affected, during this 100 flight hour transition period aluminium torque struts are to be inspected daily before the first flight of the day.
3. Use of aluminium torque struts is permitted only until 31 December 2004.
If no externally mounted hoist is installed, and if the before the first flight of the day inspection is required to be performed by the pilot, this Directive shall be entered on the Maintenance Release as maintenance required. The required visual inspection may be performed and certified by the Pilot in Command who has been trained to do the inspection by an appropriately qualified person. In this case, a copy of the Requirement document and this Directive are to be carried in the aircraft.
This Amendment becomes effective on 13 August 2003.
Background: During flight a helicopter encountered a thump-like sound, which was later followed by unusual vibrations. After the subsequent precautionary landing, it was discovered that the attachment between the tensile stress-loaded torque strut located on the right hand side of the main transmission and the fuselage structure, had ruptured. This Directive requires a visual inspection for cracking and a change of installation side of the torque struts, and eventual strut replacement.
Eurocopter EC 135 Series Helicopters
AD/EC 135/5 Amdt 3 (continued)
Amendment 1 corrected a drafting error, which significantly reduced the impact of the Directive.
Amendment 2 introduced new torque struts, which are not subject to a life limit. Installation of the new torque struts constitutes optional terminating action to the requirements of this Directive.
Amendment 3 is issued in response to revision of the related LBA AD, which introduces Revision 4 of the Requirement document.
Amendment 2 of this Airworthiness Directive became effective on 4 September 2002. Amendment 1 of this Airworthiness Directive became effective on 6 April 2001.
The original issue of this Airworthiness Directive became effective on 26 March 2001.
David Villiers
Delegate of the Civil Aviation Safety Authority 7 August 2003
The above AD is notified in the Commonwealth of Australia Gazette on 13 August 2003.
Overview
The Civil Aviation Safety Authority (CASA) introduced the Airworthiness Directive (AD) AD/EC 135/5 Amdt 3 for Eurocopter EC 135 Series Helicopters on 13 August 2003. This legislative instrument was enacted to address a specific safety issue identified in the Eurocopter EC 135 helicopters, particularly concerning the main rotor drive torque struts. The problem arose from a reported incident where a helicopter experienced a significant issue with the torque strut attachment, leading to a rupture and subsequent safety concerns. The primary objective of this AD is to ensure the airworthiness and safety of all Model EC135 helicopters by mandating a series of inspections, replacements, and operational restrictions regarding the torque struts. The directive aims to prevent similar incidents by enforcing a life limit on aluminium torque struts and requiring their replacement or inspection under certain conditions.
Scope and Application
The Airworthiness Directive (AD) AD/EC 135/5 Amdt 3 applies specifically to all Eurocopter EC 135 series helicopters, addressing the safety concern of torque struts in the main rotor drive system. This AD is issued under the Civil Aviation Safety Authority (CASA) and mandates corrective actions to mitigate the risk of torque strut failure, which could lead to significant structural damage and compromise the safety of the aircraft during flight. The AD is applicable nationwide across the Commonwealth of Australia and applies to all operators of the specified helicopter models. The directive mandates that operators replace aluminium torque struts that have exceeded a life limit of 500 flight hours with new torque struts within a specified timeframe, and prohibits the use of aluminium torque struts after 31 December 2004. The directive also stipulates specific inspection protocols for torque struts that have not yet reached the replacement threshold, requiring a daily visual inspection before the first flight of the day. The AD can be extended or further specified through subordinate instruments, ensuring that any updates or clarifications can be efficiently implemented to maintain the highest safety standards.
Key Provisions
The Airworthiness Directive (AD) AD/EC 135/5 Amdt 3, issued by the Civil Aviation Safety Authority (CASA) under subregulation 39.1 (1) of the Civil Aviation Safety Regulations 1998, mandates specific actions for Eurocopter EC 135 Series Helicopters, particularly concerning the main rotor drive torque struts. The directive applies to all Model EC135 helicopters and requires compliance with the Eurocopter Deutschland Alert Service Bulletin ECD 135-63A-002 Revision 4. The directive stipulates that torque struts should be replaced with titanium ones, which terminates the requirement of this directive. Additionally, the directive references LBA AD 2001-107/3.
The AD imposes specific obligations on the parties governed by it. It mandates a life limit of 500 flight hours for aluminium torque struts. For struts that have exceeded this limit as of the directive's effective date, they must be replaced within 100 flight hours after 13 August 2003. If the helicopter is affected and requires the inspection, it must be conducted daily before the first flight of the day. Furthermore, the use of aluminium torque struts is only permitted until 31 December 2004. If no externally mounted hoist is installed and the inspection is performed by the pilot, the directive must be entered on the Maintenance Release as maintenance required. The pilot must be trained by a qualified person, and a copy of the requirement document and the directive must be carried in the aircraft.
Non-compliance with the AD AD/EC 135/5 Amdt 3 may result in civil or criminal consequences. The specific offences, penalties, or consequences for breaching this directive are not explicitly stated in the text. However, general provisions under the Civil Aviation Safety Regulations 1998 may apply, which can include fines and imprisonment. The severity of the penalties can vary depending on the nature and extent of the non-compliance. It is important for the parties governed by the AD to adhere to the specified requirements to avoid any legal repercussions.