Using of systematic techniques became gradually important in the progress of flight, it also became clear to aircraft inventors that testing their theories with human subjects was too perilous. Wind tunnels were the primary, original, and first tool of aeronautics to be developed. Inventors built models of their planes and placed them in tunnels through which air could be blown to reproduce flight. While wind tunnels did bring valued data and evidence that positively safer than human flight. The Wright Brothers used their studies, investigations, and theories of the principles of flight by stimulating the use of the wind tunnel.
