Many of us are familiar with Leonardo Da Vinci the artist. His contributions to the culture are seemingly endless. The Last Supper and Mona Lisa are some of the most famous paintings the world over. He was also a sculptor, engineer, geometer, anatomist, and architect. He was also an inventor.
Recently, a couple of teams of engineers decided to test whether or not Leonardo Da Vinci was as brilliant as everyone thought. They decided to take two of his designs, build them and see if they would work. The two designs decided upon were: A glider, and an 80 ft weapon similar to a crossbow but firing spherical projectiles. Each team was limited in the time and materials they had to use to construct their projects.
The glider was designed by two aeronautic engineers and built in a barn. They were adamant about keeping true to the design laid out by Da Vinci and only using materials available to him in that period of time. Their glider was actually taken from two drawings: one of the main body of the glider and one of the tail piece.
In their initial tests, they first built a small model of their initial design to see if it would work. It turned out ok, so they proceeded with the big model. While building the large model, they ran into somewhat of a problem. As the wing was designed, at least as they were able to tell, there was canvas only covering the top of the wing. It was aerodynamically unsound. It would not generate the lift needed to allow the invention to work. They spent some time consulting with a Da Vinci scholar and together they made an astounding discovery. They were probably the first people to discover that Leonardo understood basic aerodynamics and had designed the wing with canvas on both sides, creating the inequality in pressure needed to create lift.
Nearing completion, they invited in their test pilot to take a look. She was the world hang-gliding champion. After initial inspection, she was extremely excited about it, but gave one stipulation…they had to implement some kind of system to allow her to control the glider. It became a tug of war. The engineers refused to consider it because it was outside of the designs set forth by Da Vinci. She refused to fly it, preferring to keep her neck unbroken.
When everything seemed to fail, their scholar found another discovery. A tiny drawing in one of Leonardo’s notebooks depicted a basic system using weight as a control device. Although it was inverted, they felt that it fell within they were keeping true to the inventor and added a similar (only they right side up) control system to the glider.
They tested it on a windy fall day on a hill familiar to their test pilot. With leads on the front and wings of the glider, they began to test gliding down the hill. Once she got the feel of the glider, the tests went beautifully. As they proceeded, they removed the leads used to help guide the glider. Once in real control, the pilot found that the simplistic control system (using the shifting of her body weight to bend the wing) worked amazingly well. It was a success. 500 years before the Wright Brothers flew at Kitty Hawk, Da Vinci had designed a working aerodynamic flying machine.
The second project undertaken was to build something between an arbalest and a catapult. Leonardo Da Vinci drew it as an 80 foot war machine, utilizing a crossbow type design like the arbalest, but launching, not arrows or spears, but a large spherical stone. It was to be used to defend a castle, launching the shot at advancing troops.
The second team was slightly larger than the first. The crew included engineers, metal workers, wood workers, etc. When designing the project, they decided to keep with the “spirit” of the machine that Da Vinci had drawn, but use their modern understanding of physics and technology to make it better.
First, they hacked off approximately 20 feet. They saw the extra footage as unnecessary. Instead of using single beams of wood to make the arms of the massive bow, they decided to make them lighter and springier using a laminate technique. They would use a more solid core, but use springier wood glued in layers on the outside, thus, theoretically, making it shoot farther. They were expecting a range much farther than what Da Vinci had estimated. For safety reasons, they used an electric crank to draw the rope back.
Their production went fairly smoothly with minimal setbacks from measuring errors. They were fairly confident that the machine would even exceed their expectations. The morning of their test drew nigh. The massive machine was transported to a nearby weapons testing facility and assembled. As it turned out…they were dead wrong. The machine was barely able to send the stone flying 40 feet. Much less than the 150-200 they were estimating.
What had happened? They were not sure. They had a few weeks to try again and they decided to go back as much as possible, to Da Vinci’s design. Amid high stress, frayed nerves and problems with finding the right supplies they slogged forward. Even when they got the lumber, the trees were problematic, warped and knotted. They did what they could with what they had and tried it again.
The second attempt with a design closer to Da Vinci’s was much more successful. They started with the machine at one quarter strength. The new design fired the missile twice as far as the first attempt using the modern design. They increased the strength. It went farther. At half strength it fired nearly 100 feet. Then it cracked. Before they could test it at full strength, it cracked, probably due to the poor materials. They were heartbroken at what happened, but were pleased with the results they got before then.
Later the head engineer saw that Da Vinci was unsure of his own design and had designed the war machine with removable sections of the bow arms, thus allowing the tension to be adjusted as needed until it could be perfected.
In short, they failed when they changed the design. They succeeded more the closer they got to the true design. It just goes to show, you can’t improve on genius.
Note: This article originally appeared in two separate parts. Here they are combined.