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 name. 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 by the Continuing Airworthiness Division (AARDG), National Aircraft Certification Branch, Transport Canada, 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 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 

24-0022 (01-2005)

1/1 No.

CF-2011-22

Issue Date 

13 July 2011 

Number: CF-2011-22 

Subject: Electrical – AC Generator Rotor Band Failure 

Effective: 28 July 2011 

Applicability: Bombardier Inc. DHC-8 Aeroplane, Models 400, 401, and 402, Serial Numbers 4001 

through 4338 with Honeywell AC Generator part number 1152218-4 or 1152218-5 

installed. 

Compliance: As indicated below, unless already accomplished. 

Background: There have been several reports of AC Generator failures in-service. The root cause has 

been attributed to an incomplete fusion in the weld joint of the AC Generator rotor band 

assembly. If not rectified, the rotor band may fail allowing the rotor windings to come in 

contact with the generator housing. The resulting debris could contaminate and 

potentially block the engine oil scavenge system, leading to loss of oil pressure and an 

in-flight shutdown of the engine. 

Bombardier has issued Service Bulletin (SB) 84-24-45 to inspect, rebuild if necessary 

and re-identify the affected AC generators to a new part number (P/N) 1152218-6 unit in 

order to rectify the problem and ensure integrity of the affected units. 

Corrective 

Actions: 

Within 6000 hours air time or 3 years after the effective date of this directive, whichever 

occurs first, inspect and re-identify the affected left and right AC generators in 

accordance with Bombardier Service Bulletin 84-24-45, dated 13 January 2011, or later 

revisions approved by the Chief, Continuing Airworthiness, Transport Canada. 

Upon installation of AC Generator P/N 1152218-6 on the aeroplane, it is not permissible 

to replace it with AC Generator P/Ns 1152218-5, 1152218-4 or 1152218-3. 

Authorization: For the Minister of Transport, Infrastructure and Communities 

ORIGINAL SIGNED BY

Derek Ferguson 

Chief, Continuing Airworthiness 

Contact: Mr. Robin Lau, Continuing Airworthiness, Ottawa, telephone 613-952-4357, facsimile 

613-996-9178 or email CAWWEBFeedback@tc.gc.caor any Transport Canada Centre.