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Engineering

The Quiet Battle Against Cavitation in Ship Propellers

Quick fact

During early submarine development, adding a seventh blade and skewing the propeller tips reduced cavitation enough to cut underwater noise dramatically – allowing detection ranges to shrink from kilometers to just hundreds of meters.

Why this is interesting

You've probably heard the rumble of a ship's engine – but what if the loudest noise isn't the engine, but the propeller silently boiling the water around it?