English: A 3-view line drawing of the Sikorsky H-6A and HOS-1.
Date
Source
Handbook [of] Erection and Maintenance Instructions: USAF Series H-6A; Navy Model HOS-1 Helicopters, AN 01-230HC-2, 1950, vi. Provided by the National Museum of the United States Air Force, Dayton, Ohio.
Author
US Military
Licensing
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