Are you sure that is not a submerging U-boat?
Looks fantastic.
Good news!: It's only 18 inches long….
Bad news!: It's only 18 inches long….
Consequently
any wave is substantial at 72nd scale - That said built with care to completely seal from the rear of the skull cap bridge forwards, it is remarkably seaworthy - The furthest I tend to let it go away from me is 75-ish yards, it's at that range that it occurs to you that sea grey and normal eyesight are not a good combination for keeping the boat under observation, let alone under control, especially on grey overcast days when the water reflects the sky to camouflage the boat almost perfectly.
I do have a 1/36 scale S-11 boat that I'm renovating/refurbing, and there's also an Italeri 1/35 S-Boot kit wing it's way to me. You could say I quite like the S-Boot design…