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.

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 Communica tions 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

24-0022 (01-2005) 1/2 No

. CF-2010-18
Issue Date 16 June 2010

Number: CF- 2010-18

Subject: Rudder Travel Limiter

− Return Springs Failure

Effective: 7 July 2010

Applicability: Bombardier Inc. Models: CL-600-2C10, serial number 10003 and subsequent CL-600-2D15 and CL-600-2D24, serial number 15001 and subsequent

Compliance: As indicated below.

Background: Rudder Travel Limiter (RTL) return sp ring, part number (P/N) E0650-069-2750S, failed prior to completion of the required enduranc e test. In addition, the replacement RTL return spring, P/N 670-93465-1 (see Note) was found to be susceptible to chafing on the primary actuator, which could also result in eventual dormant spring failure. There are two return springs in the RTL and if bot h springs failed, a subsequent mechanical disconnect of the RTL components would result in an unannunciated failure of the RTL. This, in turn, would permit an increase of rudder authority beyond normal structural limits and, in the event of a strong rudder inpu t, controllability of the aeroplane could be affected.

Note: RTL return springs, P/N 670-93465-1, were installed in production aeroplanes serial number 10266 (CL-600-2C10) and 15182 (CL-600-2D24) respectively and were introduced in-service by Service Bulletin (SB) 670BA-27-047. SB 670BA-27-047 has since been s uperseded by SB 670BA-27-055.

This directive mandates repetitive visual inspection of the RTL return springs and primary actuator, with replacem ent of parts as necessary.

Corrective Actions: Part I: Initial Inspection

A. For each aeroplane with 4000 or less hours ai r time at the effective date of this directive, inspect and replace, if requi red, the RTL return springs and primary actuator before the aeroplane has accumulated 6000 hours air time, in accordance with the Accomplishment Instructions in Bombardier Aerospace SB 670BA-27-055, dated 11 May 2010 or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada.

B. For each aeroplane with more than 4000 hours ai r time at the effective date of this directive, inspect and replace, if requi red, the RTL return springs and primary actuator within 2000 hours air time after the effective date of this directive, in accordance with the Accomplishment Inst ructions in Bombardier Aerospace SB 670BA-27-055, dated 11 May 2010 or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada.No. N ° CF-2010-18 2/2

Part II: Repetitive Inspection Within 6000 hours air time after the previous inspection (or component replacement, if applicable), inspect the RTL return springs and primary actuator in accordance with the Accomplishment Instructions in Bom bardier Aerospace SB 670BA-27-055, dated 11 May 2010 or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada.

Authorization: For Minister of Transport, In frastructure and Communities



### ORIGINAL SIGNED BY

Robin Lau for Derek Ferguson Chief, Continuing Airworthiness

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