Leonardo da Vinci designed a double hull to help protect ships from leaks after hull damage.
His ship designs included an inner and outer hull separated by a space. The basic idea was that if the outer shell were breached, the inner hull could remain watertight, reducing the chance that the vessel would immediately fill with water. This is an early example of a damage-control principle later used in shipbuilding.
Leonardo did not invent the modern tanker double hull in its present industrial form. His Renaissance sketches explored the concept as part of a broader interest in naval engineering, buoyancy, pumps, and waterproof construction. Modern double-hull vessels use carefully engineered compartments, structural members, and materials that differ from Leonardo’s proposals.
The design is often overlooked beside Leonardo’s flying machines, yet it shows his attention to safety as well as movement. A double hull also connects with a question readers commonly ask about naval design: a second shell can provide both structural protection and a barrier against flooding, depending on how the spaces are arranged.