Airworthiness Directive · Amendment 39-15533 · Stabilizers
Viking Air Limited Model DHC-2 Series Airplanes
This AD applies to Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes, all serial numbers, certificated in any category.
We are superseding an existing airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued 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:
Unless already done, do the following:
(1) For airplanes with cracks that have been previously repaired with stop-drilled holes: Within the next 12 calendar months after December 15, 1992 (the compliance date retained from AD 92-24-02), replace the tailplane front spar following Bombardier de Havilland DHC-2 (Beaver) Service Bulletin 2/47 Revision C, revised September 4, 1992.
(2) For airplanes with lightening holes (without modification 2/466): Within the next 200 hours time-in-service (TIS) after December 15, 1992 (the compliance date retained from AD 92-24-02), visually inspect the front spar web in the area of the lightening holes for cracks between the pickup brackets.
(i) If cracks are found, before further flight, incorporate Modification 2/466: installation of tailplane front spar without lightening holes, following Bombardier de Havilland DHC-2 (Beaver) Service Bulletin 2/47 Revision C, revised September 4, 1992; or Viking DHC-2 Beaver Service Bulletin 2/47, Revision E, dated January 23, 2007.
(ii) If cracks are not found, within the next 24 calendar months after December 15, 1992 (the compliance date retained from AD 92-24-02), incorporate Modification 2/466: installation of tailplane front spar without lightening holes, following Bombardier de Havilland DHC-2 (Beaver) Service Bulletin 2/47 Revision C, revised September 4, 1992; or Viking DHC-2 Beaver Service Bulletin 2/47, Revision E, dated January 23, 2007.
Note 1: Modification 2/466, installation of tailplane front spar without lightening holes, is referenced in AD 92-24-02 and Bombardier de Havilland DHC-2 (Beaver) Service Bulletin 2/47 Revision C, revised September 4, 1992; and Viking DHC-2 Beaver Service Bulletin 2/47, Revision E, dated January 23, 2007. Accomplishment of AD 92-24-02 or this AD incorporates modification 2/466.
(3) For the following airplanes: Within the next 24 calendar months after December 15, 1992 (the compliance date retained from AD 92-24-02), do the following:
(i) For airplanes having serial numbers (S/Ns) 1 through 100: Install longer pick-up brackets (modification 2/436) following deHavilland Technical News Sheet B55, dated August 1, 1952.
Note 2: Modification 2/436 was incorporated at manufacture on airplanes beginning with S/N 101. Other airplanes may have incorporated this modification in the field.
(ii) For airplanes having S/N 1 through 317: Install a gusset plate on the rear face at each of the pick-up brackets (modification 2/758) following deHavilland Technical News Sheet B55, dated August 1, 1952.
Note 3: Modification 2/758 was incorporated at manufacture on airplanes beginning with S/N 318. Other airplanes may have incorporated this modification in the field.
(4) For all airplanes: Within 200 hours time-in-service (TIS) after July 23, 2008 (the effective date of this AD) and repetitively thereafter at intervals not to exceed every 24 months, remove the tailplane front spar pick-up brackets and do a fluorescent penetrant inspection of the tailplane front spar web for cracks in the area of the pick-up brackets following Appendix A of Viking DHC-2 Beaver Service Bulletin 2/47, Revision E, dated January 23, 2007.
(5) For all airplanes: If during any of the inspections required in paragraph (f)(4) of this AD cracks are found, before further flight, replace the tailplane front spar following Viking DHC-2 Beaver Service Bulletin 2/47, Revision E, dated January 23, 2007. The 24-month repetitive fluorescent penetrant inspection is still required.
Note 4: The replacement and modifications required by this AD do not terminate the 24-month repetitive fluorescent penetrant inspection required by paragraph (f)(4) of this AD.
(6) For all airplanes: If any cracks are found as a result of the inspections required by this AD, use the following contact information to report your results: Viking Air Limited, Technical Support, 9574 Hampden road, Sidney, British-Columbia, Canada, V8L 5V5; telephone: regional 250-656-7227, North America 1-800-0663-8444, or international 1-800-6727-6727; fax: 250-656-0673; e-mail: technical.support@vikingair.com.
Note 5: This AD differs from the MCAI and/or service information as follows: No differences.
