Wright Brothers' Invention of 1903 Propeller and Genesis of Modern Propeller Theory

Abstract

During the summers of 1900, 1901, and 1902, the Wright Brothers developed, tested, and implemented, on the sands of Kitty Hawk, one of the most critical components of heavier-than-air, powered flight, that is, three-axis control. Only the assembly of a propulsion system remained to complete the world’s first successful heavier-thanair flying machine. The greatest challenge in designing and developing the propulsion system, which included an engine and transmission, was the invention of an efficient propeller. To develop the first aerial propeller, the brothers researched momentum and blade-element theory used to explain marine propeller performance. This paper discusses the fusion of momentum and blade-element theories required to invent the aerial propeller, the misconceptions of early aviators such as Langley and Maxim, and the contributions to propeller design provided by Rankine, Froude, and Drzewiecki. Also summarized are the results of the static tests the Wrights conducted on their first full-sized propeller. Additionally, the calculated performance for their 1903 propeller is quantified and summarized for the major components including thrust, drag, torque, throwdown, forward velocity, gross speed, and true slip. The paper provides the derivation of the 66% efficiency estimate for the 1903 propeller.