Airworthiness Directive · Amendment 39-19857 · Fuel
De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes
Superseded. A later AD replaced this one: AD 2022-23-01. Comply with the one in force.
This AD applies to De Havilland Aircraft of Canada Limited Model DHC-8-400, -401, and -402 airplanes, certificated in any category, manufacturer serial numbers 4001, 4003, and subsequent.
The FAA is adopting a new airworthiness directive (AD) for certain De Havilland Aircraft of Canada Limited Model DHC-8-400 series airplanes. This AD was prompted by reports of wear on fuel couplings, bonding springs, and sleeves as well as fuel tube end ferrules and fuel component end ferrules. This AD requires repetitive inspections of certain parts for discrepancies that meet specified criteria, and replacement as necessary; repetitive inspections of certain parts for damage and wear, and rework of parts; and electrical bonding checks of certain couplings. This AD also requires revising the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations. For certain airplanes, this AD allows a modification that would terminate the repetitive inspections. The FAA is issuing this AD to address the unsafe condition on these products.
For airplanes having serial numbers 4001 and 4003 through 4575 inclusive that, as of the effective date of this AD, have not done the actions specified in Bombardier Service Bulletin 84-28-21: At the applicable times specified in paragraph (g)(1) or (2) of this AD, do the actions specified in paragraphs (h)(1) and (2) of this AD.
(1) For all airplanes except those identified in paragraph (g)(2) of this AD: Within 6,000 flight hours or 36 months, whichever occurs first after the effective date of this AD.
(2) For airplanes with an original airworthiness certificate or original export certificate of airworthiness issued on or after the effective date of this AD: Within 6,000 flight hours or 36 months, whichever occurs first after the date of issuance of the original airworthiness certificate or the date of issuance of the original export certificate of airworthiness.
For airplanes having serial numbers 4001 and 4003 through 4575 inclusive that, as of the effective date of this AD, have not done the actions specified in Bombardier Service Bulletin 84-28-21: At the applicable times specified in paragraph (g)(1) or (2) of this AD, do the actions specified in paragraphs (h)(1) and (2) of this AD. Repeat the actions thereafter at intervals not to exceed 6,000 flight hours or 36 months, whichever occurs first.
(1) Do a detailed inspection of the clamshell coupling bonding wires, fuel couplings, and associated sleeves for discrepancies that meet specified criteria, as identified in, and in accordance with paragraph 3.B., “Procedure,” of the Accomplishment Instructions of Bombardier Service Bulletin 84-28-20, Revision D, dated November 23, 2018. If any conditions are found meeting the criteria specified in Bombardier Service Bulletin 84-28-20, Revision D, dated November 23, 2018, before further flight, replace affected parts with new couplings and sleeves of the same part number, in accordance with paragraph 3.B., “Procedure,” of the Accomplishment Instructions of Bombardier Service Bulletin 84-28-20, Revision D, dated November 23, 2018.
(2) Do a detailed inspection of the fuel tube end ferrules, fuel component end ferrules, and ferrule O-ring flanges for damage and wear, and rework (repair, replace, or blend, as applicable) the parts, in accordance with paragraph 3.B., “Procedure,” of the Accomplishment Instructions of Bombardier Service Bulletin 84-28-20, Revision D, dated November 23, 2018.
For airplanes having serial numbers 4001 and 4003 through 4575 inclusive: Doing a detailed inspection of the fuel tube end ferrules, fuel component end ferrules, and ferrule O-ring flanges for damage and wear, and reworking (repair, replace, or blend, as applicable) the parts; and doing a retrofit (structural rework) of the fuel couplings, isolators, and structural provisions, in accordance with paragraph 3.B., “Procedure,” of the Accomplishment Instructions of Bombardier Service Bulletin 84-28-21, Revision C, dated July 13, 2018, terminates the inspections specified in paragraphs (h)(1) and (2) of this AD.
For airplanes having serial numbers 4001, 4003 through 4489 inclusive, and 4491 through 4575 inclusive that, as of the effective date of this AD, have done the actions specified in Bombardier Service Bulletin 84-28-21, Revision A, dated September 29, 2017; and airplanes having serial numbers 4576 through 4581 inclusive: Within 6,000 flight hours or 36 months after the effective date of this AD, whichever occurs first, do the actions specified in paragraph (j)(1) or (2) of this AD.
(1) Accomplish electrical bonding checks of all threaded couplings on the inboard vent lines in the left and right wings, in accordance with paragraph 3.B., “Procedure,” of the Accomplishment Instructions of Bombardier Service Bulletin 84-28-26, Revision A, dated November 29, 2018.
(2) Do a detailed inspection of the fuel tube end ferrules, fuel component end ferrules, and ferrule O-ring flanges for damage and wear, and rework (repair, replace, or blend, as applicable) the parts; and a retrofit (structural rework) of the fuel couplings, isolators, and structural provisions in accordance with paragraph 3.B., “Procedure,” of the Accomplishment Instructions of Bombardier Service Bulletin 84-28-21, Revision C, dated July 13, 2018.
Within 30 days after the effective date of this AD, revise the existing maintenance or inspection program, as applicable, to incorporate the information specified in Q400 Dash 8 (Bombardier) Temporary Revision ALI-0192, dated April 24, 2018; and Q400 Dash 8 (Bombardier) Temporary Revision ALI-0193, dated April 24, 2018. Except as specified in paragraph (l) of this AD, the initial compliance time for doing the tasks in Q400 Dash 8 (Bombardier) Temporary Revision ALI-0192, dated April 24, 2018, is at the time specified in Q400 Dash 8 (Bombardier) Temporary Revision ALI-0192, dated April 24, 2018, or within 30 days after the effective date of this AD, whichever occurs later.
The initial compliance time for task 284000-419 is at the time specified in paragraph (l)(1) or (2) of this AD, as applicable, or within 30 days after the effective date of this AD, whichever occurs later.
(1) For airplanes having serial numbers 4001 and 4003 through 4575, inclusive: Within 18,000 flight hours or 108 months, whichever occurs first, after the earliest date of embodiment of Bombardier Service Bulletin 84-28-21 on the airplane.
(2) For airplanes having serial numbers 4576 and subsequent: Within 18,000 flight hours or 108 months, whichever occurs first, from the date of issuance of the original airworthiness certificate or original export certificate of airworthiness.
After the existing maintenance or inspection program has been revised as required by paragraph (k) of this AD, no alternative actions (e.g., inspections), intervals, or CDCCLs may be used unless the actions, intervals, and CDCCLs are approved as an alternative method of compliance (AMOC) in accordance with the procedures specified in paragraph (p)(1) of this AD.
Although Bombardier Service Bulletin 84-28-20, Revision D, dated November 23, 2018, specifies to submit certain information to the manufacturer, this AD does not include that requirement.
