Of all the inventions Leonardo da Vinci created, the war machines demonstrate his desire to impress his patrons with new military strategies. For example, in the naval tank, he proposed to equip an armed boat with a new type of devastating 'circular multiple bombard', a system of 16 cannons mounted on a rotating platform. The cannons would fire simultaneously to prevent the boat from shifting from its course.

Da Vinci also designed a tank, a heavy vehicle shaped like a tortoise with cannons all around it. Some people had thought of moving it with sails, but da Vinci devised a system of gears moved by cranks worked by eight crew inside. He had even thought of using horses inside instead of men, but the risk of animals panicking inside such a tight, noisy space made him change his mind.

Da Vinci was also interested in flying and there were two different periods in which he studied flying machines. In the first, he designed his machines to fly using the strength of a man. The second featured those that used the power of wind, such as the hang glider he designed. This contraption also had a rudder that allowed the pilot to regulate the flight.