Akron's 12 helium cells supplied about 183 tons of gross lift at normal fill, but the 109-ton structure left roughly 73 tons for fuel, ballast, crew, supplies, aircraft, and their support equipment. Its quoted cruising speed was about 43 knots, with a nominal 9,190-nautical-mile range, while maximum speed was about 73 knots. Three longitudinal keels carried walkways, control wiring, 110 fuel tanks, 44 water-ballast bags, and eight separate engine rooms. Mounting the engines internally made in-flight maintenance possible and was safer because helium would not carry an engine fire through the hull as hydrogen could. Shafts drove external propellers that could swivel or reverse thrust for maneuvering, though their airflow and vibration affected the aft control position. Two Akron propellers were replaced in 1933 with adjustable three-bladed metal units, a design later used as standard equipment aboard Macon.
Chapter · 1:19:37-1:36:47
Akron's structure, lift, and endurance tradeoffs
Three internal keels, maintainable engines, swiveling propellers, and a carefully divided lift budget made Akron a ship-like structure built inside a lifting envelope.