American plans for an eight-inch-gun cruiser submarine

Did the United States plan cruiser submarines with eight-inch guns and a seaplane?

Yes, plans existed, but none were built; the concept added complexity without solving the weaknesses of surface gun combat.

The proposal extended the same treaty-era logic that produced other large gun-armed submarines: surface scouting and cruiser-like firepower on a submersible hull. The combination magnified complexity without overcoming the practical weaknesses of fighting on the surface, which makes its cancellation look fortunate.