AD 95-22-07 Airworthiness Directives; de Havilland DHC-6 Series Airplanes

Models named: DHC-6-1, DHC-6-100, DHC-6-200, DHC-6- 300. Read the applicability below — it usually turns on serial or part numbers too.

Models DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6- 300 airplanes (serial numbers 3 through 820), certificated in any category, that do not have Modifications 6/1890, 6/1891, and 6/1892 incorporated on all four horizontal stabilizer fittings in accordance with the ACCOMPLISHMENT INSTRUCTIONS section of de Havilland Service Bulletin (SB) No. 6/513, dated October 25, 1991. Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (e) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Required as indicated, unless already accomplished. To prevent separation of the horizontal stabilizer from the airplane caused by a cracked attachment fitting, and subsequent loss of control of the airplane, accomplish the following: (a) For airplanes without Modification Nos. 6/1808 and 6/1809 incorporated, accomplish the following: (1) Within the next 50 hours time-in-service (TIS) after the effective date of this AD or 800 hours TIS after the last inspection required by superseded AD 83-26-05, whichever occurs later, and thereafter at intervals not to exceed 800 hours TIS, inspect the horizontal stabilizer forward and rear attachment fittings for cracks in accordance with de Havilland SB No. 6/438, Revision D, dated March 28, 1986. (2) If any cracks are found, prior to further flight, replace the cracked fitting with a serviceable fitting, part number (P/N) C6TPM1049-27 (forward fitting) or P/N C6TPM1050-27 (rear fitting), and incorporate Modifications 6/1890, 6/1891, and 6/1892 at each replacement fitting location in accordance with and as specified in de Havilland SB No. 6/513, dated October 25, 1991. Accomplishing these modifications terminates the repetitive inspection requirement of this AD. (b) For airplanes that have Modifications 6/1808 and 6/1809 incorporated, accomplish the following: (1) Within the next 400 hours TIS after the effective date of this AD, and thereafter at intervals not to exceed 800 hours TIS until the modifications required by paragraph (b)(3) of this AD are incorporated, inspect the rivets attaching the fittings to the horizontal stabilizer forward and rear spars for looseness in accordance with the III. ACCOMPLISHMENT INSTRUCTIONS A. INSPECTION section of de Havilland SB No. 6/513, dated October 25, 1991. (2) If rivets are found loose, prior to further flight, incorporate Modifications 6/1890, 6/1891, and 6/1892 in accordance with the ACCOMPLISHMENT INSTRUCTIONS section of de Havilland SB No. 6/513, dated October 25, 1991. (3) Within the next 2,400 hours TIS after the effective date of this AD, unless already accomplished as required by paragraph (b)(2) of this AD, incorporate Modifications 6/1890, 6/1891, and 6/1892 on all four horizontal stabilizer fittings in accordance with the ACCOMPLISHMENT INSTRUCTIONS section of de Havilland SB No. 6/513, dated October 25, 1991. (c) Incorporating Modifications 6/1890, 6/1891, and 6/1892 on all four horizontal stabilizer fittings in accordance with the ACCOMPLISHMENT INSTRUCTIONS section of de Havilland SB No. 6/513, dated October 25, 1991, is considered terminating action for the repetitive inspection requirements of this AD. (d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. (e) An alternative method of compliance or adjustment of the initial or repetitive compliance times that provides an equivalent level of safety may be approved by the Manager, New York Aircraft Certification Office (ACO), FAA, 10 Fifth Street, 3rd Floor, Valley Stream, New York 11581. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, New York ACO. Note 2: Information concerning the existence of approved alternative methods of [[Page 55189]] compliance with this AD, if any, may be obtained from the New York ACO. Note 3: Alternative methods of compliance approved in accordance with AD 83-26-05 or AD 86-15-08 (both superseded by this action) are not considered approved as alternative methods of compliance with this AD. (f) The inspections required by this AD shall be done in accordance with de Havilland Service Bulletin No. 6/438, Revision D, dated March 28, 1986. The modifications required by this AD shall be done in accordance with de Havilland Service Bulletin No. 6/513, dated October 25, 1991. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from de Havilland, Inc., 123 Garratt Boulevard, Downsview, Ontario M3K 1Y5 Canada. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., 7th Floor, suite 700, Washington, DC. (g) This amendment (39-9415) supersedes AD 83-26-05, Amendment 39-4793, and AD 86-15-08, Amendment 39-5362. (h) This amendment (39-9415) becomes effective on December 27, 1995. Issued in Kansas City, Missouri, on October 18, 1995. Michael Gallagher, Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. 95-26403 Filed 10-27-95; 8:45 am] BILLING CODE 4910-13-U