Document ID: chunk:federal_register_of_legislation:F2007L02360:body:0
Version: federal_register_of_legislation:F2007L02360
Segment Type: other
Provision Reference: 
Character Range: 0–2849

AIRWORTHINESS DIRECTIVE
On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/BELL 206/161 and issues the following AD under subregulation 39.001(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.

Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters
AD/BELL 206/161 Amdt 1  Power Turbine RPM       9/2007
                        Steady State Operation

Applicability:  Bell Helicopter Textron Canada (BHTC) Model 206L-3 serial numbers 51001 through 51612, and 206L-4 helicopters serial numbers 52001 through 52313.

                Helicopters fitted with two 250-C20R engines as per Supplementary Type Certificate (STC) SR00036SE are excluded.
Requirement:       1. Insert the appropriate flight manual revisions, BHT-206L3-FM-1, Revision 6, dated 26 April 2005, or BHT-206L4-FM-1, Revision 6, dated 26 April 2005, or later Transport Canada approved revisions, into the rotorcraft flight manual and advise the pilot of this change.

                   2. Install the decal as per Alert Service Bulletin 206L-05-134, dated 8 June 2005, or later Transport Canada revisions.  It is permissible to locally manufacture the decal with white lettering on a black background, minimum 10 point font size.

                Note:  Transport Canada AD CF-2005-28R1 dated 14 June 2007 refers.
Compliance:     Within 30 calendar days after the effective date of this directive.
                This Amendment becomes effective on 30 August 2007.
Background:     Transport Canada has been advised of multiple reports of failure of the third stage turbine wheel used in both the Rolls-Royce 250-C30S and 250-C47B engines.  There have been eight in-flight failures reported.  Rolls-Royce has determined that detrimental vibrations can occur within a particular range of turbine speed as a potential contributing factor to these failures.  BHTC revised their rotorcraft flight manual and provided a decal to inform pilots to avoid steady state operations at these engine turbine speeds.

                This amendment excludes those helicopters incorporating STC SR00036SE from the AD with no change to the technical content.

   The original issue of this AD became effective 27 October 2005.

David Punshon
Delegate of the Civil Aviation Safety Authority

20 July 2007