Airworthiness Directive · Amendment 39-16729 · Fuel
Bombardier, Inc. Model DHC-8-400 Series Airplanes
This AD applies to Bombardier, Inc. Model DHC-8-400, -401, and -402 airplanes, certificated in any category; with serial numbers (S/N) 4003, 4004, 4006, and 4008 through 4205 inclusive.
We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
For airplanes having S/Ns 4003, 4004, 4006, and 4008 through 4118 inclusive: Within 6,000 flight hours after the effective date of this AD, incorporate the modifications required in paragraphs (g)(1), (g)(2), and (g)(3) of this AD, as applicable.
(1) Incorporate Bombardier Modsum 4-126330, “Fuel Tank System Design Left and Right Side (SFAR 88) Retrofit,” by doing all the applicable actions in the Accomplishment Instructions of Bombardier Service Bulletin 84-57-09, Revision B, dated September 3, 2008.
(2) Incorporate Bombardier Modsum 4-126366, “Fuel Tank System and Fuel Indication—Wiring Identification, Segregation and Installation (High Level Sensor and Fuel Quantity Indication)—Retrofit,” by doing all the applicable actions in the Accomplishment Instructions of Bombardier Service Bulletin 84-28-04, Revision B, dated October 21, 2009.
(3) For airplanes on which Bombardier Modsum 4-302000, “Standard Option—APU Installation,” has been installed: Incorporate Bombardier Modsum 4-901425, “Fuel Feed to APU—Replacement of Couplings in Center Wing Left Side—SFAR 88,” by doing all the applicable actions in the Accomplishment Instructions of Bombardier Service Bulletin 84-28-05, dated June 28, 2006.
(h) For airplanes having S/Ns 4003, 4004, 4006, and 4008 through 4118 inclusive, do Bombardier Fuel System Limitation (FSL) Task 284000-417 (Functional Check of the Fuel Tank Components and Plumbing Lines for Electrical Bonding) contained in Section 4-1, Fuel System Limitations, of Part 2—Airworthiness Limitation Items, Revision 5, dated April 21, 2010, of Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1-84-7, at the applicable times specified in paragraphs (h)(1) and (h)(2) of this AD. Where the task specifies contacting Bombardier for technical assistance, this AD requires repairs/rework actions in accordance with a method approved by the Manager, New York Aircraft Certification Office (ACO), FAA, or Transport Canada Civil Aviation (TCCA) (or its delegated agent).
(1) Except as provided in paragraphs (h)(1)(i) and (h)(1)(ii) of this AD, for airplanes that have incorporated either Bombardier Modsum 4-126330 or 4-901425 prior to the effective date of this AD: Do Bombardier Task 284000-417 in Section 4-1, Fuel System Limitations, of Part 2—Airworthiness Limitation Items, Revision 5, dated April 21, 2010, of Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1-84-7, within 6,000 flight hours after the effective date of this AD.
(i) Airplanes on which Bombardier Task 284000-417 in Section 4-1, Fuel System Limitations, of Part 2—Airworthiness Limitation Items, Revision 5, dated April 21, 2010, of Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1-84-7, was successfully completed after incorporation of Bombardier Modsum 4-126330 or 4-901425 do not need to comply with the requirements of paragraph (h) of this AD.
(ii) Airplanes on which Bombardier Modsum 4-126330 or 4-901425 was incorporated during manufacturing of the airplane do not need to comply with the requirements of paragraph (h) of this AD.
(2) For airplanes on which neither Bombardier Modsum 4-126330 nor 4-901425 were incorporated before the effective date of this AD: Do Bombardier Task 284000-417 in Section 4-1, Fuel System Limitations, of Part 2—Airworthiness Limitation Items, Revision 5, dated April 21, 2010, of Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1-84-7, upon completion of the incorporation of Bombardier Modsum 4-126330 and, if applicable, Bombardier Modsum 4-901425.
(i) For airplanes having S/N 4003, 4004, 4006, and 4008 through 4118 inclusive, on which the date of issuance of the original Canadian standard airworthiness certificate or the date of issuance of the original Canadian export certificate of airworthiness is before September 21, 2005: Within 6,000 flight hours after the effective date of this AD, incorporate Bombardier Modsum 4-126370, “Fuel Tank System—Enhance Protective Covering for Electrical Cable Assembly,” by doing all the applicable actions in the Accomplishment Instructions of Bombardier Service Bulletin 84-28-03, Revision C, dated May 15, 2009.
For airplanes having S/Ns 4003, 4004, 4006, and 4008 through 4118 inclusive, on which the date of issuance of the original Canadian standard airworthiness certificate or the date of issuance of the original Canadian export certificate of airworthiness is on or after September 21, 2005: Within 12,000 flight hours after the effective date of this AD, incorporate Bombardier Modsum 4-126370, “Fuel Tank System—Enhance Protective Covering for Electrical Cable Assembly,” by doing all the applicable actions in the Accomplishment Instructions of Bombardier Service Bulletin 84-28-03, Revision C, dated May 15, 2009.
For airplanes having S/N 4119 through 4205 inclusive: Within 6,000 flight hours after the effective date of this AD, incorporate Bombardier Modsum 4-113580, “Fuel Indication—High Level Sensor—Application of Sealant to Exposed End of Sensor Terminal Block Screws—Special Inspection and Rectification,” by doing all the applicable actions in the Accomplishment Instructions of Bombardier Service Bulletin 84-28-07, dated August 1, 2008.
Incorporation of Bombardier Modsum 4-126330 prior to the effective date of this AD according to the instructions contained in Bombardier Service Bulletin 84-57-09, Revision A, dated March 19, 2007, meets the requirements of paragraph (g)(1) of this AD.
(m) Incorporation of Bombardier Modsum 4-126366 prior to the effective date of this AD according to the instructions contained in Bombardier Service Bulletin 84-28-04, dated June 29, 2006; or Revision A, dated November 15, 2006; meets the requirements of paragraph (g)(2) of this AD.
(n) Incorporation of Bombardier Modsum 4-126370 prior to the effective date of this AD according to instructions contained in Bombardier Service Bulletin 84-28-03, Revision B, dated October 18, 2006, meets the requirements of paragraphs (i) and (j) of this AD.
Note 1: This AD differs from the MCAI and/or service information as follows: The MCAI specifies to do Bombardier Task 284000-417 in Section 4-1, Fuel System Limitations, of Part 2—Airworthiness Limitation Items, Revision 5, dated April 21, 2010, of Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1-84-7, but does not specify what to do if the functional check finds that measured resistance exceeds the specified values. This AD requires contacting the Manager, New York ACO, FAA, or TCCA (or its delegated agent) for repair/rework instructions.
