Mackerel Class Specifications

Lead Boat: SS-204, U.S.S. Mackerel
Length: 243′ 1″
Beam: 22′ 1″
Draft: 14′ 6″ (Surface trim)
Displacement: 825 tons (surfaced); 1179 tons (submerged)
Speed: 16 knots (surfaced); 11 knots (submerged)
Diving Depth: 250′ (test depth)
Range: 6,500 miles
Crew: 4 officers, 33 enlisted
Deck Gun: 1-3″/50-calibre
Torpedoes: 4-21″ torpedo tubes (bow), 2-21″ torpedo tubes (stern), 12 torpedoes
Engines: 2-850 hp main engines, 1-60 kw auxiliary
Motors: 2-750 hp