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 ma y invalidate 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 by the Continuing Airworthiness Division (AARDG), National Aircraft Certification Branch, Transport Can ada, Ottawa, telephone 613 952-4357. URGENT URGENT URGENT URGENT URGENT URGENT URGENT URGENT URGENT


### 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 Communicat ions Centre (AARC) at Place de Ville, Ottawa, Ontario K1A 0N8 , or 1-800-305-2059 , or www.tc.gc.ca/civilaviation/communications/centre/ addr ess.asp
2 4-0022 ( 01-2005 ) 1/2 No

. CF-2011-44R1 Issue Date 1 February 2012

Number: CF-2011-44R1 Subject: Main Rotor Blade
Effective: Upon Receipt
Revision: Supersedes Airworthiness Directive CF-2011-44 Applicability: Bell Helicopter Textron Canada M odels 206L, L-1, L-3 and L-4 helicopters equipped with a main rotor blade part numbe r 206-015-001-107, -109, -111, -115, -117, -119 or -121. Compliance: As indicated below, unless already accomplished. Background: An investigation into a Model 206L-1 accident has revealed that a main rotor blade has fractured as a result of fatigue. This Airwor thiness Directive (AD) was originally issued with the understanding that the fatigue crack may occur if the following conditions are present: residual stress in the blade’s spar and a significant void in the adhesive between the inertia weight and the spar, between st ations 100 and 145. The presence of a crack in the spar could lead to the total failure of the blade and the loss of the helicopter. Subsequent investigation into a second acci dent on a Model 206L helicopter has led to the following conclusions:

• Presently, there is no reliable inspecti on method to detect the crack on the blade before blade failure, and

• To insure continued airworthiness, a reduc ed life limit is necessary, irrespective of the size of an adhesive void.
Revision R1 of this AD introduces a life limit of 1400 hours air time on all affected main rotor blades regardless of previous inspections performed.
Corrective Actions: Part I – Verification Before next flight from the effective date of this AD, verify the part number and the serial number of each main rotor blade to determine if the blade is affected by this AD, in accordance with the Accomplishment Instruct ions Part I of the Bell Alert Service Bulletin (ASB) 206L-09-159 Rev. A dated 13 November 2009, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada.No. N ° CF-2011-44R1 2/2

Part II – Introduction of a lower life limit From the effective date of this AD, all affect ed main rotor blades are subject to a life limit of 1400 hours air time. Consequently, all affe cted main rotor blades must be removed from service prior to the accumulation of 1400 hours air time. For those main rotor blades that are already at or above 1400 hours air ti me, remove the blades from service before next flight.
Authorization: For the Minister of Transport, Infrastructure and Communities


### ORIGINAL SIGNED BY Derek Ferguson Chief, Continuing Airworthiness
Contact: 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.