Bamboo Dragonflies and Italians in China? Finch's helicopter sketches provided inspiration for the invention of modern helicopters and pointed out the correct thinking direction. They are recognized as the starting point of the history of helicopter development.

Bamboo dragonfly, also known as flying spin, is a strange invention of our ancestors. Some people think that bamboo dragonfly, a folk toy, was produced in China in 400 BC.

/kloc-at the end of 0/9, in Milan Library, Italy, people discovered Da? An imaginary helicopter map drawn by Finch in 1475. Da? Finch said that his invention only provided a helicopter power plant, not a working plane. But westerners say that this is the earliest blueprint for helicopter design.