COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 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.
Eurocopter AS 355 (Twin Ecureuil) Series Helicopters
AD/AS 355/68 “TRW-SAMM” Main Servocontrols 10/2002
Applicability: AS 355 helicopters version F, F1, F2, and N equipped with “TRW-SAMM’ main servocontrols Part Number (P/N) SC 8042 or SC 8043 which underwent their last complete overhaul or repair since overhaul at “HAWKER PACIFIC AEROSPACE’, USA before March 1 2002.
Requirement: Remove the servocontrols and return them to “HAWKER PACIFIC AEROSPACE” for a check of the thread condition and application torque as required in Eurocopter AS 355 Alert Telex No. 67.00.23.
Note: DGAC 2002-315-069(A).
Compliance: 1. For servocontrols held as spares; prior to fitment to an aircraft.
2. For servocontrols that have been in service for less than 1000 flight hours since overhaul; within 550 flight hours or 3 October 2003, whichever comes first.
3. For servocontrols that have been in service between 1000 and 1300 flight hours since overhaul; prior to 1550 flight hours or 3 July 2003, whichever comes first.
4. For servocontrols that have been in service for more than 1300 flight hours since overhaul; within 250 flight hours or 3 March 2003 whichever comes first.
This Airworthiness Directive becomes effective on 3 October 2002.
Background: An incorrect torque loading was found to have been applied to the end fitting that attaches the servocontrol cylinder to the upper ball end fitting. The incorrect torque may lead to failure of the threads on the fitting, leading to separation of the upper-end fitting and result in loss of control of the helicopter.
James Coyne
Delegate of the Civil Aviation Safety Authority 23 August 2002
The above AD is notified in the Commonwealth of Australia Gazette on 11 September 2002.
Overview
The Civil Aviation Regulations 1998, as amended, address various aspects of civil aviation safety in Australia, and include provisions for Airworthiness Directives which are issued by the Civil Aviation Safety Authority (CASA) to address identified safety concerns. One such Airworthiness Directive (AD), specifically AD/AS 355/68, pertains to the Eurocopter AS 355 (Twin Ecureuil) Series Helicopters, particularly those equipped with “TRW-SAMM” main servocontrols. This AD was introduced to address a safety issue identified with the torque application on the servocontrols, which could potentially lead to thread failure and loss of control of the aircraft. The AD mandates specific actions to rectify the unsafe condition, including the removal and inspection of the affected servocontrols by a designated service provider. The objective of this AD is to ensure the continued airworthiness and safety of the affected aircraft by correcting the identified issue before it can result in any operational risk.
Scope and Application
The Airworthiness Directive (AD) set out in the Civil Aviation Regulations 1998 applies specifically to Eurocopter AS 355 (Twin Ecureuil) Series Helicopters, particularly those versions F, F1, F2, and N, which are equipped with "TRW-SAMM" main servocontrols Part Number (P/N) SC 8042 or SC 8043. These must have undergone their last complete overhaul or repair at "HAWKER PACIFIC AEROSPACE" in the USA before March 1, 2002. This AD mandates actions to rectify an identified unsafe condition, specifically related to the incorrect torque loading applied to the end fitting that attaches the servocontrol cylinder to the upper ball end fitting. This incorrect torque could potentially lead to thread failure, separation of the upper-end fitting, and resultant loss of control of the helicopter. The directive outlines specific compliance timelines based on the flight hours since overhaul, with stringent deadlines set to ensure the safety of the aircraft. The AD is applicable within the jurisdictional reach of the Commonwealth of Australia and is enforced by the Civil Aviation Safety Authority (CASA).
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105, contains the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, which includes AD/AS 355/68 for Eurocopter AS 355 (Twin Ecureuil) Series Helicopters. The AD mandates specific actions to rectify an unsafe condition identified in the “TRW-SAMM” main servocontrols of certain AS 355 helicopters. This AD applies to AS 355 helicopters versions F, F1, F2, and N that have “TRW-SAMM” main servocontrols with Part Numbers SC 8042 or SC 8043, which underwent their last complete overhaul or repair at “HAWKER PACIFIC AEROSPACE” before March 1, 2002 (section 1). The requirement outlined in this AD is to remove the affected servocontrols and return them to “HAWKER PACIFIC AEROSPACE” for a thorough check of the thread condition and application torque, as detailed in Eurocopter AS 355 Alert Telex No. 67.00.23 (section 2). The directive also includes compliance timelines based on the flight hours since overhaul, with specific deadlines set for each category of flight hours to ensure the safety of the helicopters (section 3).
The AD imposes specific obligations on the operators and maintainers of the affected helicopters. Operators must ensure that the identified servocontrols are either removed before being fitted to an aircraft if held as spares or are checked and potentially replaced before reaching specified flight hour thresholds. For servocontrols that have already been in service, the AD sets strict timelines based on the number of flight hours since overhaul, requiring that the checks and necessary actions be taken within the specified periods (section 3). Additionally, operators must ensure that all maintenance actions are carried out in accordance with the instructions provided by Eurocopter and CASA, and any modifications must be documented and logged appropriately (section 2).
Failure to comply with this Airworthiness Directive can result in significant safety risks, as the incorrect torque loading identified in the AD could lead to the failure of the threads on the fitting, potentially causing separation of the upper-end fitting and resulting in the loss of control of the helicopter. While the Civil Aviation Regulations 1998 do not explicitly outline specific penalties for non-compliance with Airworthiness Directives, non-compliance can lead to severe civil and criminal consequences, including fines and imprisonment under the Civil Aviation Act 1988. The maximum penalties for breaches of safety regulations in aviation can include substantial fines for corporations and imprisonment for individuals responsible for ensuring compliance.