AD 91-05-13

91-05-13 BOEING OF CANADA, LTD., DE HAVILLAND DIVISION: Amendment 39- 6910. Docket No. 90-NM-243-AD.

Applicability: de Havilland Model DHC-7 series airplanes, Serial Numbers 3 through 36, inclusive, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent possible malfunction of the wing flight spoilers, accomplish the following:

A. Within 180 days after the effective date of this AD, replace the outboard (Modification Nos. 7/1927 and 7/1951) and inboard (Modification Nos. 7/1928 and 7/1952), right and left wing flight spoilers spigot fittings, in accordance with the Accomplishment Instructions in de Havilland Service Bulletins 7-27-25, Revision B, and 7-27-26, Revision B, both dated January 28, 1983.

B. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, New York Aircraft Certification Office (ACO), ANE-170, FAA, New England Region.

NOTE: The request should be submitted directly to the Manager, New York ACO, ANE-170, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Manager, New York ACO, ANE-170.

C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.

All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Boeing of Canada, Ltd., de Havilland Division, Garratt Boulevard, Downsview, Ontario M3K 1YK, Canada. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington; or at the FAA, New England Region, New York Aircraft Certification Office, 181 South Franklin Avenue, Valley Stream, New York.

Thisamendment (39-6910, AD 91-05-13) becomes effective on March 29, 1991.