Were US subs Diesel-electric powered?

[Sailor Steve]

Okay! Here's the rundown from Conway's All The World's Fighting Ships: 1906-1921 and 1922-1946:

'S' Class, Elco type (S-1, S-18 - S-41): BS diesels plus electric motors.

'S' Class, Lake type (S-2): BS diesels plus electric motors.

'S' Class, Navy Yard type (S-3 - S-17): NSLE, MAN or BS diesels plus electric motors.

'S' Class, 2nd group (S-42 - S-47): BS diesels plus electric motors.

Barracuda class: diesels plus electric motors.

Argonaut: diesels plus electric motors.

Narwhal class: diesels plus electric motors.

Dolphin: diesels plus electric motors.

Cachalot class: diesels plus electric motors.

Porpoise class: diesel-electric plus electric motors.

Shark class: diesel-electric plus electric motors.

Perch class: diesel-electric plus electric motors.

Salmon class: diesels (composite drive) plus electric motors.

Sargo class: diesels (composite drive) plus electric motors.

Seadragon class: diesel-electric plus electric motors.

Gato, Balao and Tench classes: diesel-electric plus electric motors.



So the Porpoise class were the first to have diesel-electric drives. The Salmon and Sargo classes reverted to direct-drive diesel because of rising fears of leaks disabling the electrical systems. The Seadragon group of the Sargo class went back to diesel-electric, and they stayed with that system afterwards.

Conway's isn't clear as to what is meant by (composite drive), so I can't explain that; I just copied it as they have it.

I also can't verify the information with another source, but the editor for the United States ships section was Norman Friedman, so it's almost certainly correct.

So there it is.

[JSF]

On Gatos the wheel shaft was connected to emotor via geared housing. On Balaos and Tench the shaft was directly off the emotor. This was done to further quiet underwater noise. In addition Balao and Tench used 5 blade low cavitation wheels. Gato 4 blade.