COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Bell Helicopter Textron Canada (BHTC) 407 Series Helicopters
AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/BELL 407/1 Amdt 4 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.
AD/BELL 407/1
Amdt 5
Never Exceed Speed Reduction 6/2001 DM
Applicability: All BHTC Model 407 helicopters.
Requirement: 1. Remove the copy of AD/BELL 407/1 Amdt 4 from the front of the Flight Limitations section of the Aircraft Flight Manual and advise all pilots of its removal.
2. Remove the Vne limitation placard and airspeed indicator redline limits which were installed in accordance with AD/BELL 407/1 Amdt 4.
3. Unless already accomplished, install an airspeed actuated pedal stop in accordance with BHTC Alert Service Bulletin (ASB) 407-99-33.
4. Unless already accomplished, Replace the Vne placards in accordance with ASB 407-99-33, remove the temporary instrument markings and install new airspeed limitations decals in accordance with Part II of ASB 407-99-33, and remove all Temporary Revisions to the AFM inserted by previous Directive amendments and insert Temporary Revision titled Vne Increase to 140 KIAS dated 17 December 1999.
Note 1: Requirements 3 and 4 were originally required by AD/BELL 407/1 Amdt 3 with a compliance time of 31 January 2001. As AD/BELL 407/1 Amdt 4 had an effective date of 11 January 2001, the compliance time of amendment 3 was never met.
Note 2: Transport Canada AD CF-2001-01R1 refers.
Compliance: Before 31 May 2001.
This Amendment becomes effective on 26 April 2001.
Background: Transport Canada had received three reports of Model 407 helicopter accidents in which the aft section of the tail boom was severed by the tail rotor. In two of the cases an unexpected right yaw, followed by a large left directional control input, were reported prior to the tail boom strike. The actions required by this Directive were to minimise the risk of a tail boom strike during flight; pending further engineering towards reinstatement of 140 KIAS Vne.
COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Amendment 1 mandated the technical provisions of ASB 407-99-27, and allowed an increased Vne of 130 KIAS up to 20 degrees C and 125 KIAS above 20 degrees C.
Amendment 2 allowed an increase in Vne to 130 KIAS above 20 degrees C, as a result of flight tests at elevated temperatures.
Amendment 3 required installation (before 31 January 2001) of a pedal stop which repositioned itself relative to airspeed, and so provided terminating action for the Directive.
Amendment 4 was prompted by an accident in which a helicopter flying at 140 knots was destroyed by suspected tail rotor strike to the tail boom. Pending further evaluation of the accident, to minimise the risk of a tail boom strike during flight, the never-exceed speed (Vne) is to be reduced.
Amendment 5 is issued in response to a revision of the related Transport Canada AD which removes the current Vne restriction imposed as a result of an accident. The accident investigation has revealed no data to confirm a tail rotor strike as the cause.
Amendment 4 of this Directive became effective on 12 January 2001. Amendment 3 of this Directive became effective on 18 May 2000.
The original issue of this Directive became effective on 20 May 1999.
David Alan Villiers
Delegate of the Civil Aviation Safety Authority 19 April 2001
The above AD is notified in the Commonwealth of Australia Gazette on 26 April 2001.
Overview
The Civil Aviation Regulations 1998, under Part 39 - 105 Civil Aviation Safety Authority Schedule of Airworthiness Directives, address safety concerns related to civil aviation operations within Australia. Enacted by the Commonwealth of Australia, these regulations aim to ensure that all aircraft meet specific airworthiness standards to safeguard passengers and crew. This particular legislative instrument, F2006B04624, pertains to Bell Helicopter Textron Canada (BHTC) 407 Series Helicopters and was introduced to address the identified risk of tail boom strikes during flight, following reports of accidents in which the aft section of the tail boom was severed by the tail rotor. The policy objective is to enhance flight safety by mandating corrective actions on the affected aircraft to mitigate the identified risks. The Civil Aviation Safety Authority, as the delegate, issues Airworthiness Directives to ensure compliance with these safety standards.
Scope and Application
The Civil Aviation Regulations 1998, under Part 39 - 105, mandate the Civil Aviation Safety Authority (CASA) to issue Airworthiness Directives (AD) to ensure aircraft safety. Specifically, the AD/BELL 407/1 Amdt 5 applies to all Bell Helicopter Textron Canada (BHTC) Model 407 helicopters registered in Australia, requiring certain modifications to prevent tail boom strikes by the tail rotor. This directive revokes the previous AD/BELL 407/1 Amdt 4, which had set a lower never-exceed speed (Vne) to mitigate risk, but has now been updated based on new findings. The AD requires the removal of the previous Vne limitation placards and airspeed indicator redline limits, and mandates the installation of an airspeed actuated pedal stop and new airspeed limitations decals. Additionally, pilots must be informed of these changes and any temporary revisions to the Aircraft Flight Manual must be updated accordingly. This directive must be complied with before 31 May 2001 and became effective on 26 April 2001, with its scope and application extending across all relevant helicopters within Australia, overseen by CASA as the regulatory body.
Key Provisions
The Civil Aviation Regulations 1998 (CAR 1998) under Part 39 - 105, specifically Amendment 5 to Airworthiness Directive (AD) AD/BELL 407/1, pertains to Bell Helicopter Textron Canada (BHTC) 407 Series Helicopters. This directive revokes the previous Amendment 4 and issues new requirements to address safety concerns. The AD applies to all BHTC Model 407 helicopters. It mandates the removal of the AD/BELL 407/1 Amdt 4 from the Flight Limitations section of the Aircraft Flight Manual and informs all pilots of its removal (Requirement 1). It also requires the removal of the Vne limitation placard and airspeed indicator redline limits installed in accordance with AD/BELL 407/1 Amdt 4 (Requirement 2). Additionally, the AD requires the installation of an airspeed actuated pedal stop if not already done, and the replacement of Vne placards and installation of new airspeed limitations decals in accordance with specific Bell Helicopter Textron Canada Alert Service Bulletin (ASB) 407-99-33 (Requirements 3 and 4). These actions are necessary to mitigate the risk of a tail boom strike during flight.
The obligations imposed by this AD on the operators and maintainers of BHTC Model 407 helicopters include ensuring that the specified modifications and updates to the Aircraft Flight Manual are implemented. This involves removing the previous AD and its associated markings, installing new components as per the ASB, and ensuring all temporary revisions inserted by previous directives are removed. Operators must also ensure that all pilots are informed of these changes and understand the new flight limitations. Compliance with these directives is crucial to maintaining the airworthiness of the aircraft and ensuring safe operation.
Failure to comply with the AD can result in significant safety risks, including the potential for structural failure during flight. While specific penalties for non-compliance are not detailed in the directive itself, non-compliance with Civil Aviation Regulations could lead to enforcement actions by the Civil Aviation Safety Authority (CASA). These actions may include fines, suspension of airworthiness certificates, or other regulatory penalties. Operators and maintainers are therefore strongly encouraged to adhere to the directives to avoid any legal or safety repercussions.