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Leonardo da Vinci (1452-1519)

In 2020, a University of Maryland engineering team designed and tested the technology underlying da Vinci’s hovering device. The result was Crimson Spin, an unmanned quadcopter drone that actually flew on several brief journeys.

Issue: 03-2023By Joseph Noronha

What place can someone born in 1452 have in an aviation Hall of Fame, considering that the first powered flight happened only in 1903? As Dane Cook said, “Every great thing starts with an idea.” And Leonardo da Vinci, world famous for paintings like the “Mona Lisa” and “The Last Supper”, was certainly not lacking in ideas – ideas about aviation that were centuries ahead of his time. Long before the first person could take to the skies, theories about how this might be practically achieved germinated in his fertile mind.

Leonardo da Vinci was born on April 15, 1452, in the hill town of Vinci, Central Italy. Till the nineteenth century, he was generally regarded only as a painter. However, he was also an astronomer, sculptor, geologist, mathematician, botanist, inventor, engineer, architect and musician. All this came to light only after 1800, and not from any surviving works, but from his long-lost notebooks concerning science and technology. Thousands of pages of writings and drawings, today referred to as “Leonardo’s codices”, reveal that he was an intellectual and technical genius as well as an inspired inventor. Among his many pursuits was a quest for the possibility of human flight. It dominated his attention from the late 1480s to the mid-1490s.

When Leonardo da Vinci was employed by the Milanese royal court to work on military technology, he became fascinated by the potential value of reconnaissance from the air. So fascinated, that he produced more than 35,000 words and 500 sketches dealing with the properties of air, bird flight and flying machines. Although these studies are distributed throughout his codices, there is one work devoted almost entirely to the subject. “Codex on the Flight of Birds” c. 1505, now held at the Royal Library of Turin, comprises 18 folios. It has a detailed examination of avian flight, noting for the first time that the centre of gravity of a flying bird does not coincide with its centre of pressure. There are scores of pages analysing the motion of the wings of bats and birds whilst in straight flight, in turns, while gliding etc. He explained the behaviour of birds as they ascend against the wind and arrived at the basic concept of a stall. Long before Newton defined gravity, Leonardo hinted at the action of this mysterious force. His observations of gliding flight by birds led him to the basic principles of how a mechanical device that emulated bird flight would need to be balanced using wings and tail-plane. He noted the crucial importance of lightweight structures, even though the technology of the day had no such possibilities. He actually constructed a number of potential flying devices and attempted to launch some of them from a hill near Florence, but without success.

One design was what is now called an ornithopter – a flying machine operated by flapping mechanical wings like a bird. Leonardo da Vinci’s ornithopter resembled a giant bat, with a wingspan of over 33 feet, and a frame of pine covered with raw silk to create a light but sturdy membrane. The pilot would lie face down and spin cranks connected to a rod-and-pulley system with both hands and feet while using a head piece for steering a small rudder. The contraption was remarkable for how the entire human body would be used to maximise the power generated by the lone pilot. However, as da Vinci himself would probably have realised, while the flying machine may have been capable of flying through the air, no human body could have generated enough power to get it off the ground.

Similarly, da Vinci’s proposed hovering device closely resembles a rudimentary helicopter, 400 years before such craft began to appear. It was to be built of wood, reeds and taffeta. He envisioned a spring, wound by crank turners, building up and storing energy. That stored energy could be released in a quick unwinding burst, spinning the screw rotor: “A small model can be made of paper with a spring like metal shaft that after having been released, after having been twisted, causes the screw to spin up into the air.” While Leonardo’s design was aerodynamically sound, he lacked the modern materials necessary to build a lightweight and durable blade. He described its helical screw as being made of linen, with the pores stopped up by starch – a rather impractical proposition. However, in 2020, a University of Maryland engineering team designed and tested the technology underlying da Vinci’s hovering device. They added a modified screw system to a modern drone. The result was Crimson Spin, an unmanned quadcopter drone that actually flew on several brief journeys.

Leonardo da Vinci died at Clos Lucé, France, on May 2, 1519. All in all, he was perhaps one of the most fascinating people history has ever known.