Airworthiness Directive · Amendment 39-18077 · Flight controls
Viking Air Limited Airplanes
This AD applies to Viking Air Limited Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes, all serial numbers, certificated in any category.
We are adopting a new airworthiness directive (AD) for Viking Air Limited Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes. This AD results from mandatory continuing airworthiness information (MCAI) issued by the aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as failed locknuts on the horizontal stabilizer attach bracket. We are issuing this AD to require actions to address the unsafe condition on these products.
Unless already done, do the following actions in paragraphs (f)(1) and (f)(2).
(1) Within the next 50 hours time-in-service after February 18, 2015 (the effective date of this AD), inspect the six locknuts of the horizontal stabilizer attach brackets to determine their type following the Accomplishment Instructions in Viking Alert Service Bulletin No. V2/0007, Revision `NC', dated April 29, 2013.
(2) If during the inspection required in paragraph (f)(1) of this AD any of the installed locknuts is of the part number (P/N) MS21042 type, before further flight, remove the locknut and replace with a new P/N MS21044 type locknut following the Accomplishment Instructions in Viking Alert Service Bulletin No. V2/0007, Revision `NC', dated April 29, 2013.
(3) After February 18, 2015 (the effective date of this AD), do not install P/N MS21042 type locknuts on the horizontal stabilizer attach bracket.
