Airworthiness Directive · Amendment 39-21963 · Wing structure
Viking Air Limited (Type Certificate Previously Held by Bombardier Inc.) Airplanes
This AD applies to Viking Air Limited (type certificate previously held by Bombardier Inc.) Model DHC-3 airplanes, all serial numbers, certificated in any category, with a wing strut assembly part number (P/N) C3W100 (all dash numbers) installed.
The FAA is adopting a new airworthiness directive (AD) for Viking Air Limited (type certificate previously held by Bombardier Inc.) Model DHC-3 airplanes with a certain wing strut assembly installed. 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 identifies the unsafe condition as fatigue damage of the wing struts. This AD requires a bolt hole eddy current inspection of the lug plate holes, a visual and fluorescent dye penetrant inspection of the lug fittings, and a visual and eddy current surface scan inspection of the wing strut assemblies. This unsafe condition could lead to failure of the wing strut, which could result in an in- flight breakup of the wing. The FAA is issuing this AD to address the unsafe condition on these products.
(1) For airplanes that have not been modified with Supplemental Type Certificate (STC) SA00438NY: Before each wing strut assembly P/N C3W100 accumulates 20,000 hours total time-in-service (TIS) or within 30 days after the effective date of this AD, whichever occurs later, remove the wing strut assembly P/N C3W100 from service and replace with a new (zero hours TIS) part. Thereafter, remove each wing strut assembly P/N C3W100 from service and replace with a new (zero hours TIS) part before accumulating 20,000 hours total TIS.
(2) For airplanes with a wing strut assembly P/N C3W100 with more than 2,500 hours total TIS on the effective date of this AD, regardless of whether the airplane has been modified with STC SA00438NY: Within 30 days after the effective date of this AD, inspect the wing strut assembly and attachment hardware for cracks, corrosion, and damage, in accordance with the Accomplishment Instructions in Viking DHC-3 Otter Alert Service Bulletin No. V3/0011, Revision NC, dated November 26, 2019, except you are not required to contact Viking.
(3) For all affected airplanes: Within 30 days after completing the inspection required by paragraph (g)(2) of this AD or within 30 days after the effective date of this AD, whichever occurs later, report the results of the inspection to Viking using the inspection reply form in Viking DHC-3 Otter Alert Service Bulletin No. V3/0011, Revision NC, dated November 26, 2019.
