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 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 b y the Continuin g Airworthiness Division ( AARDG ) , National Aircraft Certification Branch, Trans p ort Canada, Ottawa, tele p hone 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 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/ address.asp
2 4-0022 ( 01-2005 ) 1/2 No

. CF-2012-07 Issue Date 27 January 2012

Number: CF- 2012-07 Subject: Cockpit “Engine Fire, Check Fire De tect” Warning and “FUEL OFF” Handle Lights Failure to Reset Effective: 10 February 2012 Applicability: Bombardier Inc. DHC-8 aeroplane Models 400, 401 and 402, Serial Numbers 4001 through 4373. Compliance: As indicated below, unless already accomplished. Background: There have been engine fires on DHC-8 Series 400 aeroplanes, where the “ENGINE FIRE, CHECK FIRE DETECT” warning and “FUEL OFF” handle lights failed to reset and remained illuminated after the fire was extingui shed. An investigation has revealed that the existing engine fire/overheat detector assemblies “ A dvance Pneumatic Detectors (APD)” may fail to reset after ac tivation due to permanent deformation of the detector switch diaphragm after being exposed to high temperatures. This abnormal condition of a continued engine fire indication in the cockpit, after the actual fire has been extinguished, is misleadi ng and may influence the pilot’s decision to conduct a potentially hazardous “off-airport” landing, which is considered an unsafe condition that warrants mitigating action. To mitigate this potentially hazardous condition, Bombardier has issued multiple service bulletins (SBs) to replace all three affect ed APDs with new detector assemblies that are not susceptible to the subject diaphragm deformation when exposed to excessive heat. This Airworthiness Directive (AD) mandat es the incorporation of Bombardier SBs 84-26-08A, 84-26-09A and 84-26- 12A on the affected aeroplanes. Corrective Actions: Within 6000 flight hours or 30 months, whichever comes first, from the effective date of this AD, replace all three engine fire/overheat detector assemblies “APDs”, at both left and right hand side engine locations, as per the following instructions: Part I – Nacelle – Engine Primary Zone : Remove APD part number (P/N) 10-1098 and install APD P/N 10-1098-01, in accordance with Bombardier Aerospace SB 84-26-08 Rev. ‘A’, dated 12 May 2011, or later revisions approved by the Chief, C ontinuing Airworthiness, Transport Canada. Part II – Nacelle – Landing Gear Primary Zone : Remove APD P/N 10-1097 or 10-1097-01 and install APD P/N 10-1097-02, in accordance with Bombardier Aerospace SB 84-26-09 Rev. ‘A’, dated 12 May 2011, or later revisions approved by the Chief, C ontinuing Airworthiness, Transport Canada.No. N ° CF-2012-07 2/2

Part III – Propeller Engine Controller : Remove APD P/N 10-1096, 10-1096-01 or 10-1096-02 (introduced per SB 84-26-10A, with serial number of all numeric characte rs) and install APD P/N 10-1096-02 (with serial number of three alpha and four numeric charac ters), in accordance with Bombardier Aerospace SB 84-26-12 Rev.’A’, dated 13 Dece mber 2011, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada.
Authorization: For the Minister of Transport, Infrastructure and Communities 

### ORIGINAL SIGNED BY Derek Ferguson Chief, Continuing Airworthiness Contact: A.K. Durrani, Continuing Airworthiness, Ottawa, telephone 613-952-4357, facsimile 613-996-9178 or e-mail CAWWEBFeedback@tc.gc.ca or any Transport Canada Centre.