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             Another important milestone in aviation, was the understanding of aerodynamics. Sir George Cayley, a British theorist, was acclaimed as the father of aerodynamics. He established a solid foundation of aerodynamic principles that were essential to the success of other pioneers. In 1875, Thomas Moy created a large model that had twin 12ft propellers with 6 blades each! Interestingly enough these blades could be adjusted to produce maximum thrust under certain conditions, an early recognition of the need for changing blade pitch. .

             The most influential aviation pioneers were the Wright brothers. They had concluded that a propeller was simply a whirling wing, but didn't have the appropriate information to consult when comprehending the fundamental principles of blade shape. This dilemma made designing the propeller one of the Wright brothers most challenging problems. Despite the lack of previous information to consult, the brothers were able to learn, through investigation and trial/error, that large propeller diameters would produce high thrust for a given power input. The brothers also determined that high torque produced by large, slow turning blades adversely affected the flying qualities (p-factor). On their first aircraft, they utilized 8 ½ ft propellers installed behind the wind to minimize airflow disturbance, incorporated counter-rotating propellers to eliminate the problems associated with torque, and gained thrust efficiency by reducing the blades' rotational speed using a chain and sprocket transmission. The Wright brother's propeller was 66% efficient which was much higher that any other propeller of the time. .

             These advancements led to the development of the first generation of well-designed propellers. One of the first designs was the "Integrale", developed by Lucien Chauviere, the world's first industry standard propeller manufacturer. By 1910, the number of propeller producers multiplied, and numerous advancements were made.