That's not as fun as actually being in the sub and controlling it. It's like a CV set way points and let it go. How would you control the torpedoes? Would the subs hunt in "wolf packs" or would the just be off doing their own thing.
Launch a seaplane from a submarine...?
I know there was a Russian or Japanese 'aircraft carrier' submarine but Im pretty sure it never left the drawing board.
The Japanese did that, i only believe once tho. They were off the coast of Oregon i believe, they lunched a biplane with incendiary bombs. They intended to start huge forest fires, hoping that it would delay the US from attacking them. But it was a "successful" mission in part of the plane lunched and was recovered, but the forest fires they intending on starting was a bust.
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I would like to see a battle ship before a submarine.