74-08-11 DEHAVILLAND: Amendment 39-1819. Applies to DHC-6 airplanes Serial Numbers 136 to 350 inclusive, 353, 356, 360 to 366 inclusive, and 368 certificated in all categories.
To prevent rivet failures in the side seat rail attachment structure of inward facing seats which are forward of the right-hand cabin door between Fuselage Stations 239.0 and 290.3, accomplish the following in accordance with de Havilland Service Bulletin No. 6/302, dated November 8, 1973:
1. For airplanes that presently have inward facing seats installed, within the next 200 hours in service after the effective date of this AD, unless already accomplished, inspect in accordance with the Accomplishment Instructions of the Service Bulletin, and alter, as necessary, in accordance with the Service Bulletin or in accordance with an approved equivalent alteration.
2. For future initial installation of inward facing seats, attachments must be in accordance with Details "A", "B", "C", and "D" of theService Bulletin, or approved equivalent attachments.
3. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 522(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to de Havilland Aircraft of Canada, Ltd., Attention: Product Support Department, Downsview, Ontario, Canada. These documents may also be examined at the Eastern Region, Engineering and Manufacturing Branch, Federal Building, J.F.K. International Airport, Jamaica, N.Y. 11430, and at the FAA headquarters, 800 Independence Avenue, S.W., Washington, D.C. A historical file on this AD which includes the incorporated material in full is maintained by the FAA at its headquarters in Washington, D.C., and at the Eastern Region.
4. Equivalent alterations and attachments must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region.
5. The compliance time may be increased by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region, upon receipt of substantiating data submitted through a local FAA maintenance inspector.
This amendment is effective April 18, 1974.