Transport Transports Canada Canada TP 7245E



# AIRWORTHINESS DIRECTIVE

The following airworthiness directive (AD) may be applicable to an aircraft which our records indicate is registered in your na me. ADs are issued pursuant to Canadian Aviation Regulation (CAR) 521 Division X . Pursuant to CAR 605.84 and the further details of CAR Standard 625, Appendix H , the continuing airworthiness of a Canadian registered aircraft is contingent upon compliance with all applicable ADs. Failure to comply with the requirements of an AD may invalidat e the flight authorization of the aircraft. Alternative means of compliance shall be applied for in accordance with CAR 605.84 and the above-referenced Standard

. This AD has been issued b y the Continuin g Airworthiness Division ( AARDG ) , National Aircraft Certification Branch, Trans p ort Canada, Ottawa, tele p hone 613 952-4357. 

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TRANSPORT CANADA EMERGENCY AIRWORTHINESS DIRECTIVE PLEASE FORWARD IMMEDIATELY TO THE PERSON RESPONSIBLE FOR THE OPERATION AND MAINTENANCE OF YOUR AIRCRAFT

Pursuant to CAR 202.51 the registered owner of a Canadian aircraft shall, within seven days, notify the Minister in writing of any change of his or her name or address. To request a change of address, contact the Civil Aviation Communications Centre (AARC) at Place de Ville, Ottawa, Ontario K1A 0N8 , or 1-800-305-2059
, or www.tc.gc.ca/civilaviation/communications/centre/ address.asp

2 4-0022 ( 01-2005 ) 1/2 No

. CF-2011-17R1 Issue Date 19 December 2011

Number: CF-2011-17R1
Subject: Incorrect Assembly of Hydraulic Servo Actuators

Revision: Supersedes Airworthiness Directive CF-2011-17

Effective: 22 December 2011
Applicability: Bell Helicopter Textron Canada helicopters: Model 407, serial numbers 53000 through 53900, 53911 through 53999 and 54000 through 54081 equipped with servo actuators part number 206-076-062-105 or 206-076-062-107. Model 427, serial numbers 56001 through 56077, 58001 and 58002 equipped with servo actuators part number 206-076-062-109 or 206-076-062-111.
Compliance: As indicated below, unless already accomplished.
Background: Transport Canada was advised that a quality escape by a supplier has occurred and a number of Bell Helicopter hydraulic servo actuators may have a loose nut, shaft, and clevis assembly. The loose connection is due to improper lock washer installation. This discrepancy is not traceable or identifiable e xcept by inspection. A disconnect of the affected components may lead to loss of control of the helicopter. The original issue of this directive mandates inspections and rectification of the nut, shaft and clevis assembly for all affected component s identified when the directive was issued. Since the publication of the original issue of this directive, it has been discovered that additional servo actuator serial numbers may be affected. Therefor e, Revision one (R1) of this directive is issued to extend the cover age of the one-time inspection to all installed actuators. Those actuators al ready inspected according to the original issue of this directive are to be re-identified with the letter “V” at the end of the part number.

Corrective Actions: A. Before next flight perform a one-time visual inspection and the applicable rectifications on the hydraulic servo actuator, in accordance with the Accomplishment Instructions of the applicable Alert Serv ice Bulletin (ASB) listed below, or later revisions approved by the Chief, Conti nuing Airworthiness, Transport Canada:No. N ° CF-2011-17R1 2/2

Helicopter Model Alert Service Bulletin Date

407 407-11-96 Revision B 22 August 2011

427 427-11-35 Revision B 22 August 2011
Previous inspections and rect ifications carried out in accordance with the original issue of this directive meet the requirements of this paragraph.
B. For actuators which have already b een inspected and have incorporated the applicable rectifications in accordance with the original issue of this directive and those actuators that have met the require ments of paragraph A above, within the next 110 hours air time, re-identify the actuator data plate by adding the letter “V” at the end of the part number, in accordance with the applicable ASB listed in the above table.
A s of the effective date of this directive, servo actuators wi th part numbers listed in the applicability section of this directive shall not be installed on Bell Helicopter Textron Canada helicopter Models 407 and 427, unless the actuator complies with the requirements of this directive and is identif ied with the letter “V” after the part number.

Authorization: For the Minister of Transport, Infrastructure and Communities



### ORIGINAL SIGNED BY
Derek Ferguson Chief, Continuing Airworthiness

Contact: Mr. Bogdan Gajewski, Continuing Airworthiness, Ottawa, telephone 613-952-4357, facsimile 613-996-9178 or e-mail CAWWEBFeedback@tc.gc.ca or any Transport Canada Centre.