It was probably Orville Wright who first had the idea. He was the ideas brother, Wilbur the steady one. Their early work was in helping their father, a clergyman, printing his religious leaflets but then they printed their own information paper and got into selling the latest wonder, the bicycle.
Learning all they could about bicycle mechanisms laid fthe foundation for studying other forms of transport. Some aerodynamics were already known, but it was the death of one of the great glider pilots of the late nineteenth century, that engaged them in the study of flying and the design of flying machines via gliding experiments.
They then decided to educate themselves in the theory and state of the art of flying and this led to their own exploits.