A glider sailplane built by students of the Lawrence Technical High School in Massachusetts is pulled into the air by a Chevrolet. From Chevrolet Leader News Newsreel Vol. 2 No. 1. Reupload of a previously uploaded film with improved video & sound. Originally a public domain film from the Library of Congress Prelinger Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/Glider_(...) Wikipedia license: http://creativecommons.org/licenses/b... A glider or sailplane is a type of glider aircraft used in the sport of gliding. It has rigid wings and an undercarriage. Some gliders, known as motor gliders, are also used for gliding and soaring, but have engines which can be used for extending a flight and, for some types, for take-off. Aircraft such as hang gliders and paragliders are foot-launched and so are described in separate articles, though their differences from sailplanes are covered below. Glider aircraft that are used for purposes other than recreation, for example for military purposes, do not soar. Sports gliders benefit from creating the least drag for any given amount of lift, and this is best achieved with long, thin wings and a fully faired narrow cockpit. Aircraft with these features are able to climb efficiently in rising air and can glide long distances at high speed with a minimum loss of height in between... Sir George Cayley's gliders achieved brief wing-borne hops from around 1849. In the 1890s Otto Lilienthal built gliders using weight shift for control. In the early 1900s the Wright Brothers built gliders using movable surfaces for control. In 1903 they successfully added an engine. After World War I gliders were built for sporting purposes in Germany and in the United States. Germany's strong links to gliding were to a large degree due to post-WWI regulations forbidding the construction and flight of motorised planes in Germany, so the country's aircraft enthusiasts often turned to gliders and were actively encouraged by the German government, particularly at flying sites suited to gliding flight like the Wasserkuppe. The sporting use of gliders rapidly evolved in the 1930s and is now their main application. As their performance improved, gliders began to be used for cross-country flying and now regularly fly hundreds or even thousands of kilometres in a day if the weather is suitable. In 1930, pilot Frank Hawks flew the "Texaco Eaglet" with tow plane from San Diego to New York over eight days, helping to popularize the activity in the United States... The early gliders were made mainly of wood with metal fastenings, stays and control cables. Later fuselages made of fabric-covered steel tube were married to wood and fabric wings for lightness and strength. New materials such as carbon-fiber, fiber glass and Kevlar have since been used with computer-aided design to increase performance. The first glider to use glass-fiber extensively was the Akaflieg Stuttgart FS-24 Phönix which first flew in 1957. This material is still used because of its high strength to weight ratio and its ability to give a smooth exterior finish to reduce drag. Drag has also been minimized by more aerodynamic shapes and retractable undercarriages...
