I would guess that the bending and twisting pressures of swelling and crashing water, rather dwarfs the potential forces the cylinders can drag through air in a

I would guess that the bending and twisting pressures of swelling and crashing water, rather dwarfs the potential forces the cylinders can drag through air in a storm, especially while they are not spinning. And I'd guess they would be engineered to break off, before harming the hull if that could be a threat.