Da Vinci was somewhat obsessed with flying and conceptualized several different machines to do so over his years. In this tested design, the flying machine was lifted by a rotor powered by four men. It did not work because the body of the machine itself rotated in the opposite direction to the rotor.

Can Leonardo's ornithopter really fly?

Most of Leonardo's aeronautical designs were ornithopters, machines that employed flapping wings to generate both lift and propulsion. He sketched such flying machines with the pilot prone, standing vertically, using arms, using legs. ... Leonardo could never have overcome this basic fact of human physiology.

Why didnt Leonardo da Vinci's flying machine work?

He had written up designs for everything from bridges, to tank, to helicopters. Originally Da Vinci wished to emulate birds and bats, so he designed a contraption that would allow its wearer to flap their wings in order to create thrust. Da Vinci's design of a man-powered ornithopter.