Airworthiness Directive · Amendment 39-19815 · Fuselage
De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes
This AD applies to De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Model DHC-8-401 and -402 airplanes, certificated in any category, serial numbers 4327, 4330, 4337, 4342, 4350, 4352, 4362, 4367, 4372, 4375, 4376, 4378, 4383, 4384, 4385, 4388, 4391, 4392, 4396, and 4397.
The FAA is adopting a new airworthiness directive (AD) for certain De Havilland Aircraft of Canada Limited Model DHC-8-401 and - 402 airplanes. This AD was prompted by a report that certain fuselages were delivered with nonconforming keel tension fittings and stringer end fittings. This AD requires a detailed visual inspection of stringer end fittings and keel fittings for loose or working fasteners, signs of wear, and corrosion, and repair if necessary; and a general visual inspection of the keel tension fitting and stringer end fittings, as applicable, and repairs and replacement of the keel and stringer end fittings if necessary. The FAA is issuing this AD to address the unsafe condition on these products.
Within 8,000 flight hours or 5 years after the effective date of this AD, whichever occurs first: Do a detailed visual inspection of the stringer end fittings and keel fittings at fuselage stations X373.15 and X428.50 for loose and working fasteners, signs of wear, and corrosion in accordance with paragraph 3.B. of the Accomplishment Instructions of De Havilland Aircraft of Canada Limited Service Bulletin 84-53-75, Revision A, dated August 2, 2019. If any loose or working fasteners, signs of wear, or corrosion are found during any inspection required by this paragraph, before further flight, repair using a method approved by the Manager, New York ACO Branch, FAA; or Transport Canada Civil Aviation (TCCA); or De Havilland Aircraft of Canada Limited's TCCA Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAO-authorized signature. Doing the actions specified in Bombardier Service Bulletin 84-53-66 does not constitute compliance with the actions specified in this paragraph.
Except for airplanes identified in paragraph (i) of this AD: Before accumulating 40,000 total flight cycles or within 12 months after the effective date of this AD, whichever occurs later, do the inspections specified in paragraphs (h)(1) and (2) of this AD.
(1) Do a general visual inspection of the keel tension fittings at fuselage stations X373.15 and X428.50 for non-conformance conditions (oversize, elongated, and off angle conditions) in accordance with paragraph 3.B. of the Accomplishment Instructions of Bombardier Service Bulletin 84-53-74, dated August 29, 2018. If any non-conformance condition is found, before further flight, replace the keel tension fittings at fuselage stations X373.15 and X428.50, including doing all applicable repairs, in accordance with paragraph 3.B. of the Accomplishment Instructions of Bombardier Service Bulletin 84-53-74, dated August 29, 2018; except where Bombardier Service Bulletin 84-53-74, dated August 29, 2018, specifies to contact Bombardier, before further flight, repair using a method approved by the Manager, New York ACO Branch, FAA; or TCCA; or De Havilland Aircraft of Canada Limited's TCCA DAO. If approved by the DAO, the approval must include the DAO-authorized signature.
(2) Do a general visual inspection of the stringer end fittings at fuselage stations X373.15 and X428.50 for non-conformance conditions (i.e., excessive depth Hi-Lite fastener hole chamfers and installation too close to the fillet radius), in accordance with paragraph 3.B. of the Accomplishment Instructions of Bombardier Service Bulletin 84-53-74, dated August 29, 2018. If any non-conformance condition is found, before further flight, replace the stringer end fittings at fuselage stations X373.15 and X428.50, including doing all applicable repairs and an eddy current or fluorescent dye penetrant inspection for cracks of all blended areas and fasteners, in accordance with paragraph 3.B. of the Accomplishment Instructions of Bombardier Service Bulletin 84-53-74, dated August 29, 2018; except where Bombardier Service Bulletin 84-53-74, dated August 29, 2018, specifies to contact Bombardier, before further flight, repair using a method approved by the Manager, New York ACO Branch, FAA; or TCCA; or De Havilland Aircraft of Canada Limited's TCCA DAO. If approved by the DAO, the approval must include the DAO-authorized signature.
For airplanes on which the actions specified in Bombardier Service Bulletin 84-53-69 have been accomplished prior to the effective date of this AD: Before accumulating 40,000 total flight cycles or within 12 months after the effective date of this AD, whichever occurs later, do a general visual inspection of the stringer end fittings at fuselage stations X373.15 and X428.50 for non-conformance conditions (i.e., excessive depth Hi-Lite fastener hole chamfers and installation too close to the fillet radius) in accordance with paragraph 3.B. of the Accomplishment Instructions of Bombardier Service Bulletin 84-53-74, dated August 29, 2018. If any non-conformance condition is found, before further flight, replace the stringer end fittings at fuselage stations X373.15 and X428.50, including doing all applicable repairs and an eddy current or fluorescent dye penetrant inspection for cracks of all blended areas and fasteners, in accordance with paragraph 3.B. of the Accomplishment Instructions of Bombardier Service Bulletin 84-53-74, dated August 29, 2018; except where Bombardier Service Bulletin 84-53-74, dated August 29, 2018, specifies to contact Bombardier, before further flight, repair using a method approved by the Manager, New York ACO Branch, FAA; or TCCA; or De Havilland Aircraft of Canada Limited's TCCA DAO. If approved by the DAO, the approval must include the DAO-authorized signature.
If, during any eddy current or fluorescent dye penetrant inspection required by paragraph (h)(2) or (i) of this AD, any cracking is found, before further flight, repair using a method approved by the Manager, New York ACO Branch, FAA; or TCCA; or De Havilland Aircraft of Canada Limited's TCCA DAO. If approved by the DAO, the approval must include the DAO-authorized signature.
