Leonardo da Vinci proposed a double hull to make ships more resistant to leaks and damage.
A double-hull design places an inner hull inside an outer hull, creating a protected space between them. If the outer skin is breached, the inner hull can remain watertight. Leonardo included related shipbuilding ideas among his engineering studies, applying geometry and structural thinking to naval design.
The concept is often connected with Leonardo’s work on military and commercial vessels. His notebooks contain many ship sketches, including hull forms, paddle mechanisms, and methods for improving maneuverability. Not every drawing represents a complete buildable vessel, so individual proposals should not be treated as tested ships.
Modern tankers use double hulls to reduce pollution after collisions or groundings, but their engineering is far more complex than Leonardo’s Renaissance sketches. The underlying principle is the same: separate the external surface from a second watertight barrier.