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An Encyclopedia of the History of Technology part 65

An Encyclopedia of the History of Technology part 65. This one of a kind encyclopedia presents the entire field of technology from rudimentary agricultural tools to communication satellites in this first of its kind reference source. Following an introduction that discusses basic tools, devices, and mechanisms, the chapters are grouped into five parts that provide detailed information on materials, power and engineering, transportation, communication and calculation, and technology and society, revealing how different technologies have together evolved to produce enormous changes in the course of history | PART THREE TRANSPORT Lilienthal s activities inspired the American railway engineer Octave Chanute to make a number of hang-gliders in 1896. Chanute was an enthusiast who had collected a great deal of information on earlier theories and experiments which he summarized in a seminal work Progress in Flying Machines published in 1894 his practical experiments were therefore founded on a firm basis of knowledge and engineering experience. The most significant machine was a biplane hangglider with a cruciform stabilizing tail unit which was successfully and regularly flown on the shores of Lake Michigan by Chanute s assistant A. M.Herring. Herring attempted to develop a power unit for a version of this machine and claimed to have made two short hops with an engine driven from a compressed gas supply sufficient for 15 seconds running in October 1898. THE WRIGHT BROTHERS Wilbur and Orville Wright of Dayton Ohio were directly inspired by reading about Lilienthal s gliding activities. They were the first seriously to consider the problem of controlling a flying machine. Earlier experimenters had explicitly or implicitly considered the flying machine as a stable vehicle to be steered in the desired direction. The Wrights recognized that a machine moving in three dimensions in a turbulent atmosphere would need more dynamic control by its pilot. Their solution was a biplane wing structure with a wire-braced truss structure. The central part was rigid but the outer parts could be twisted under the pilot s control. The tip section on one side was inclined at a greater angle to the airflow thus lifting that wing the other tip was twisted in opposition to lower it and the wing thereby banked. This inclined the lift vector and thus turned the aircraft. At first they used a fixed vertical fin at the rear of the aircraft like the flights of an arrow to stabilize the aircraft then converted this into a rudder act ing simultaneously with the wing twist and finally separated the two .