Glider World

Gliding is an amazing spare time activity and competitive sport in which pilots fly un-powered aircraft known as gliders or sailplanes. Properly, the term gliding refers to descending flight of a heavier-than-air craft, whereas soaring is the correct term to use when the craft gains altitude or speed from rising air. When soaring conditions are good enough, experienced pilots can fly hundreds of kilometres before returning to their home airfields, and occasionally flights over 1,000 kilometres are made. However, if the weather deteriorates, they may need to land elsewhere, but motorglider pilots can avoid this by starting an engine.

At the same time as many glider pilots merely enjoy the sense of achievement, some competitive pilots fly in races around pre-defined courses. These competitions test the pilots' abilities to make best use of local weather conditions as well as their flying skills. Local and national competitions are organized in many countries and there are also biennial World Gliding Championships. Powered aircraft and winches are the two most common means of launching gliders. These and other methods (apart from self-launching motor-gliders) require assistance from other participants. Gliding clubs have thus been established to share airfields and equipment, train new pilots and maintain high safety standards.

The progress of heavier-than-air flight in the half-century between Sir George Cayley's coachman in 1853 and the Wright brothers mainly involved gliders. However, the sport of gliding only emerged after the First World War as a result of the Treaty of Versailles, which imposed severe restrictions on the manufacture and use of single-seat powered aircraft in Germany. Thus, in the 1920s and 1930s, while aviators and aircraft makers in the rest of the world were working to improve the performance of powered aircraft, the Germans were designing, developing and flying ever more efficient gliders and discovering ways of using the natural forces in the atmosphere to make them fly farther and faster. The active support of the government ensured a ready supply of experienced aviators ready to be trained in warplane operation when the treaty was abrogated in preparation for World War II by the Third Reich - though for most of the participants, their sport had no military overtones. The first German gliding competition was held at the Wasserkuppe in 1920, organized by Oskar Ursinus. The best flight lasted two minutes and set a world distance record of 2 km. Within ten years, it had become an international event in which the achieved durations and distances had increased greatly. In 1931, Gunther Grönhoff flew 272 km (169 miles) from Munich to Czechoslovakia, further than had been thought possible.

Gliding extend to many other countries in the 1930s. In the 1936 Summer Olympics in Berlin gliding was a demonstration sport, and it was scheduled to be a full Olympic sport in the 1940 Games. A glider, the Olympia, was developed in Germany for the event, but World War II intervened. By 1939 the major gliding records were held by Russians, including a distance record of 748 km (465 miles).

Throughout the war, civilian gliding in Europe was chiefly suspended. Although some military operations in WWII involved military gliders, they did not soar and so are unrelated to the sport of gliding. Nonetheless, several German fighter aces in the conflict, including Erich Hartmann, began their flight training in gliders. Gliding did not return to the Olympics after the war, for two reasons: first, the shortage of gliders following the war; and second, the failure to agree on a single model of competition glider. (Some in the community feared doing so would hinder development of new designs.) The re-introduction of air sports such as gliding to the Olympics has been occasionally proposed by the world governing body, the FAI, but this has been rejected on the grounds of lack of public interest. In many countries during the 1950s a large number of trained pilots wanted to continue flying. Many were also aeronautical engineers. They started both clubs and manufacturers, many of which still exist. This stimulated the development of both gliding and gliders; for example, the Soaring Society of America grew from 1,000 members then to its present total of 12,500. The increased numbers of pilots, greater knowledge and improving technology helped set new records, so that the pre-war altitude record was doubled by 1950, and the first 1,000-km (621 statute miles) flight was achieved in 1964. New materials such as glass fiber and carbon fiber, advances in wing shapes and airfoils, electronic instruments, GPS and improved weather forecasting have since allowed many pilots to make flights that were once extraordinary. Today over 500 pilots have made flights over 1,000 km.

In place of Olympic competition there are the World Gliding Championships. The initial event was held at the Wasserkuppe in 1937. Since WWII it has been held every two years. There are now six classes open to both sexes, plus three classes for women and two junior classes. Germany, the sport's birthplace, is still a center of the gliding world: it accounts for 30% of the world's glider pilots, and the three major glider manufacturers are still based there. However the sport has been taken up in many countries and there are now over 116,000 active glider pilots, plus an unknown number of military cadets. Each year many other people experience their first glider flight. It does not matter whether the countries are flat or mountainous, hot or temperate, because gliders can soar in most places.

If talking about soaring, glider pilots can stay airborne for hours by flying through air that is ascending as fast or faster than the glider itself is descending, thus gaining potential energy. The most commonly used sources of rising air are: thermals (updrafts of warm air), ridge lift (found where the wind blows against the face of a hill and is forced to rise) and wave lift (standing waves in the atmosphere, analogous to the ripples on the surface of a stream). Ridge lift rarely allows pilots to climb much higher than about 600 m (2,000 ft) above the terrain; thermals, depending on the climate and terrain, can allow climbs in excess of 3,000 m (10,000 ft) in flat country and much higher above mountains. Wave lift has allowed a glider to reach an altitude of 15,447 m (50,671 ft). In a few countries, gliders may continue to climb into the clouds in uncontrolled airspace, but in many countries the pilot must stop climbing before reaching the cloud base.

In the beginning of our topic we would stop and review more closely Gliders aircrafts. Gliders or Sailplanes as they are often referred to, are a light engineless aircrafts designed to glide after being towed aloft or launched from a catapult, they come in all shapes, and sizes. There are single place trainers, two place, and even three place craft. Sailplanes are constructed from such materials as: aluminum, wood, or a special fabric stretched over steel tubing. Some sailplanes are extremely refined, designed for maximum performance and constructed from exotic composite materials while others are designed for training new pilots necessitating rugged economy.

Wingspans can fluctuate from under 40 feet to nearly 90 feet. And the empty weight (without a pilot) of sailplanes can be as little as 250 lbs, or nearly 114 kg. Competition sailplanes use carbon and fiberglass composites molded into extremely strong and accurate shapes to provide strong, lightweight structures using advanced aerodynamics to create the most refined aircraft ever created. Sailplane pilots fit snuggly in the cockpit and control the manipulate aircrafts control surfaces. All gliders are wings and tail are removable and slide securely into a special Just like cars the sky is the limit when it comes to price available for $15,000 to $50,000 and top of the line racing competition types cost between $50,000 and $100,000.

The two widespread methods of launching gliders are by aerotow and by winch. When aerotowed, the glider is towed behind a powered aircraft using a rope about 60 meters (about 200 ft) long. The glider's pilot releases the rope after reaching the desired altitude, but the rope can also be released by the towplane in an emergency. Winch launching uses a powerful stationary engine located on the ground at the far end of the launch area. The glider is attached to one end of 800-1200 metres (about 2,500-4,000 ft) of wire cable and the winch then rapidly winds it in. More rarely, powerful automobiles are used to pull gliders into the air, by pulling them directly or through the use of a pulley in a similar manner to the winch launch. Elastic ropes can also be used to launch gliders off slopes if there is sufficient wind blowing up the hill. The glider will then gain height using ridge lift.

In China, kites rather than gliders were used for military scouting to gain important information. However the Extensive Records of the Taiping Era (978) suggests that a true glider was designed in the 5th century BC by Lu Ban, a contemporary of Confucius. There is also a report from the History of Northern Dynasties (659) and Zizhi Tongjian (1084) that Yuan Huangtou in Ye made a successful glide, taking off from a tower in 559. Abbas Ibn Firnas invented the first weight shift aircraft (hang glider) and is also claimed as the inventor of the first manned glider in 875 by fixing feathers to a wooden frame fitted to his arms or back. Written accounts at the time suggest that he made a ten minute flight. Abbas was seriously injured in the resulting crash. The first heavier-than-air (i.e. non-balloon) aircraft to be flown in Europe was Sir George Cayley's series of gliders which achieved brief wing-borne hops from around 1804. Santos Dumont, Otto Lilienthal, Percy Pilcher, John J. Montgomery, and the Wright Brothers are other pioneers who built gliders to develop aviation. After the First World War gliders were built for sporting purposes in Germany and in the United States (Schweizer brothers). The sporting use of gliders rapidly evolved in the 1930s and is now the main application. As their performance improved gliders began to be used to fly cross-country and now regularly fly hundreds or even thousands of kilometers in a day, if the weather is suitable. Military gliders were then developed by a number of countries, particularly during World War II, for landing troops. A glider was even built absolutely secretly by POWs as a potential escape method at Oflag IV-C near the end of the war in 1944. The space shuttle orbiters do not use their engines after re-entry at the end of each spaceflight, and, as you may have guessed, land as gliders.