Leonardo da Vinci proposed a double hull to make a ship’s structure more resistant to damage.
A double hull places an inner and outer hull around a ship, creating a protective space between them. Leonardo’s maritime studies included ideas for improving ship safety and strength through layered construction. The concept anticipated a principle later used in shipbuilding, especially where protection against puncture or leakage was important.
Leonardo’s notebooks contain many naval designs, including boats, paddle mechanisms, and systems for working underwater. His double-hull idea was a design proposal rather than a documented shipbuilding project completed by him. Modern double-hull ships are engineered with materials, compartments, and structural calculations far beyond Renaissance practice.
The concept is sometimes associated only with modern oil tankers, but double hulls have broader uses. They can provide an additional barrier and help contain a leak after outer-shell damage. Leonardo’s proposal is notable because it shows him applying layered structural protection to naval engineering centuries before the feature became common in modern ships.