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57-514: The Schreder HP-15 sailplane prototype was designed by Richard Schreder as a personal mount in which to challenge the 1969 U.S. National Soaring Championships. With an extreme 33:1 aspect ratio and a relatively low empty weight, the HP-15 was expected to generate less induced drag and therefore higher performance. The type achieved excellent glide ratios in fast flight, but had disappointing climbing ability, due to extensive flow separation on

114-570: A subarctic climate ( Dfc ). The average annual temperature in Wasserkuppe is 6.0 °C (42.8 °F). The average annual rainfall is 1,106.1 mm (43.55 in) with December as the wettest month. The temperatures are highest on average in July, at around 14.8 °C (58.6 °F), and lowest in January, at around −2.2 °C (28.0 °F). The Wasserkuppe weather station has recorded

171-413: A turn and slip indicator are used when there is zero visibility. Increasingly, anti-collision warning systems such as FLARM are also used and are even mandatory in some European countries. An Emergency Position-Indicating Radio Beacon ( ELT ) may also be fitted into the glider to reduce search and rescue time in case of an accident. Much more than in other types of aviation, glider pilots depend on

228-423: A variometer and an airband radio ( transceiver ), each of which may be required in some countries. A transponder may be installed to assist controllers when the glider is crossing busy or controlled airspace. This may be supplemented by ADS-B . Without these devices access to some airspace may become increasingly restricted in some countries. In countries where cloud-flying is allowed, an artificial horizon or

285-501: A day if the weather is suitable. Early gliders had no cockpit and the pilot sat on a small seat located just ahead of the wing. These were known as " primary gliders " and they were usually launched from the tops of hills, though they are also capable of short hops across the ground while being towed behind a vehicle. To enable gliders to soar more effectively than primary gliders, the designs minimized drag. Gliders now have very smooth, narrow fuselages and very long, narrow wings with

342-406: A flight and even, in some cases, for take-off . Some high-performance motor gliders (known as "self-sustaining" gliders) may have an engine-driven retractable propeller which can be used to sustain flight. Other motor gliders have enough thrust to launch themselves before the engine is retracted and are known as "self-launching" gliders. Another type is the self-launching "touring motor glider", where

399-418: A glider's contest ID when flying in close proximity to one another to alert them of potential dangers. For example, during gatherings of multiple gliders within thermals (known as "gaggles"), one pilot might report "Six-Seven-Romeo I am right below you". Fibreglass gliders are invariably painted white to minimise their skin temperature in sunlight. Fibreglass resin loses strength as its temperature rises into

456-423: A height of 300 metres (1,000 ft). Glide slope control devices are then used to adjust the height to assure landing at the desired point. The ideal landing pattern positions the glider on final approach so that a deployment of 30–60% of the spoilers/dive brakes/flaps brings it to the desired touchdown point. In this way the pilot has the option of opening or closing the spoilers/air-brakes to extend or steepen

513-433: A high aspect ratio and winglets . 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

570-705: A higher speed at any given glide angle. This is an advantage in strong conditions when the gliders spend only a small amount of time climbing in thermals. The pilot can jettison the water ballast before it becomes a disadvantage in weaker thermal conditions. Another use of water ballast is to dampen air turbulence such as might be encountered during ridge soaring . To avoid undue stress on the airframe, gliders must jettison any water ballast before landing. Most gliders are built in Europe and are designed to EASA Certification Specification CS-22 (previously Joint Aviation Requirements -22). These define minimum standards for safety in

627-728: A large degree due to post-World War I 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

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684-508: A minimum loss of height in between. Sailplanes have rigid wings and either skids or undercarriage . In contrast hang gliders and paragliders use the pilot's feet for the start of the launch and for the landing. These latter types are described in separate articles, though their differences from sailplanes are covered below. Sailplanes are usually launched by winch or aerotow, though other methods, auto tow and bungee, are occasionally used. These days almost all gliders are sailplanes, but in

741-460: A result, the Wasserkuppe now had a gliding school, workshops for building gliders and a funded research facility. Alexander Lippisch was appointed as the managing director of the new society. Virtually every German aeronautical engineer and test pilot of note during the 1920s and 1930s spent time building, testing, and flying aircraft at the Wasserkuppe, including the Günter brothers , Wolf Hirth ,

798-445: A separate control. Although there is only a single main wheel, the glider's wing can be kept level by using the flight controls until it is almost stationary. Pilots usually land back at the airfield from which they took off, but a landing is possible in any flat field about 250 metres long. Ideally, should circumstances permit, a glider would fly a standard pattern , or circuit , in preparation for landing, typically starting at

855-684: A significant distance forward for a small decrease in altitude. In North America the term 'sailplane' is also used to describe this type of aircraft. In other parts of the English-speaking world, the word 'glider' is more common. Gliders benefit from producing very low drag for any given amount of lift, and this is best achieved with long, thin wings , a slender fuselage and smooth surfaces with an absence of protuberances. Aircraft with these features are able to soar – climb efficiently in rising air produced by thermals or hills. In still air, sailplanes can glide long distances at high speed with

912-456: A wide range of characteristics such as controllability and strength. For example, gliders must have design features to minimize the possibility of incorrect assembly (gliders are often stowed in disassembled configuration, with at least the wings being detached). Automatic connection of the controls during rigging is the common method of achieving this. The two most common methods of launching sailplanes are by aerotow and by winch. When aerotowed,

969-417: Is known as "soaring". By finding lift sufficiently often, experienced pilots fly cross-country , often on pre-declared tasks of hundreds of kilometers, usually back to the original launch site. Cross-country flying and aerobatics are the two forms of competitive gliding . For information about the forces in gliding flight, see lift-to-drag ratio . Pilots need some form of control over the glide slope to land

1026-471: Is sometimes confusion about gliders/sailplanes, hang gliders and paragliders. In particular, paragliders and hang gliders are both foot-launched. The main differences between the types are: Eight competition classes of glider have been defined by the FAI . They are: A large proportion of gliders have been and are still made in Germany, the birthplace of the sport. In Germany there are several manufacturers but

1083-445: Is sufficient wind blowing up the hill. Bungee launching was the predominant method of launching early gliders. Some modern gliders can self-launch by using retractable engines or just retractable propellers. (see motor glider ). These engines can use internal combustion or battery power. Once launched, gliders try to gain height using thermals , ridge lift , lee waves or convergence zones and can remain airborne for hours. This

1140-447: The variometer article for more information). Variometers are sometimes fitted with mechanical or electronic devices to indicate the optimal speed to fly for given conditions. The MacCready setting can be input electronically or adjusted using a ring surrounding the dial. These devices are based on the mathematical theory attributed to Paul MacCready though it was first described by Wolfgang Späte in 1938. MacCready theory solves

1197-518: The Horten brothers , Robert Kronfeld , Hans Jacobs , Heini Dittmar , Alexander Lippisch , Willy Messerschmitt , Hanna Reitsch , Peter Riedel , and Alexander Schleicher . Beverley Shenstone , who was later a key part of the design team for the Spitfire , flew gliders at Wasserkuppe in 1930. This period saw great advances in new technologies such as flying wings and rocket -powered flights. In

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1254-508: The Space Shuttle with a glide ratio of 4.5:1. High aerodynamic efficiency is essential to achieve a good gliding performance, and so gliders often have aerodynamic features seldom found in other aircraft. The wings of a modern racing glider are designed by computers to create a low-drag laminar flow airfoil . After the wings' surfaces have been shaped by a mould to great accuracy, they are then highly polished. Vertical winglets at

1311-440: The variometer , which is a very sensitive vertical speed indicator , to measure the climb or sink rate of the plane. This enables the pilot to detect minute changes caused when the glider enters rising or sinking air masses. Most often electronic 'varios' are fitted to a glider, though mechanical varios are often installed as back-up. The electronic variometers produce a modulated sound of varying amplitude and frequency depending on

1368-604: The 1930s the "Ehrenhalle" (Hall of Honor) was constructed in the Lilienthal Haus, with heavy bronze doors opening into a large hall with a stained glass window. The centerpiece is a larger-than-life bronze figure of Otto Lilienthal lying on an (empty) tomb. It is a memorial to all pilots who have died in aviation accidents. The inscription on the memorial is Lilienthal's famous last words: "Opfer müssen gebracht werden" roughly meaning: "Sacrifices must be made." In Nazi Germany , gliding activities became largely controlled by

1425-399: The 1960s is a stub . You can help Misplaced Pages by expanding it . Glider (sailplane) A glider or sailplane is a type of glider aircraft used in the leisure activity and sport of gliding (also called soaring). This unpowered aircraft can use naturally occurring currents of rising air in the atmosphere to gain altitude. Sailplanes are aerodynamically streamlined and so can fly

1482-549: The Wasserkuppe where it has remained popular since. Beginning in the 1970s, the newer sport of hang gliding has also found a home there. Following the reunification of Germany and demise of the Soviet Union , the surveillance and radar installations were removed in the 1990s. In 1970, to commemorate the 50th anniversary of the first competition, the Deutsches Segelflugmuseum (German Sailplane Museum)

1539-525: The administrative district Fulda 5.3 kilometres (3.3 mi) north of Gersfeld . Other villages nearby are Poppenhausen (4.7 kilometres (2.9 mi) west - south west) and Wüstensachsen (5 kilometres (3.1 mi) east, part of Ehrenberg, Hesse ). It is part of the Rhön Biosphere Reserve . The Wasserkuppe sources the spring of the river Fulda (the western source of the Weser ) and

1596-561: The competition had become an international event, drawing pilots from all over Europe and even the United States. Also in 1924 'Rhönvater' (Rhön father) Oskar Ursinus convinced the then secretary of air transport for the ministry of transportation Ernst Brandenburg  [ de ] to turn the new gliding club into a state funded research organization. This started the Rhön-Rossitten Gesellschaft and as

1653-425: The control stick, thus creating friction between the skid and the ground. The wing tips also have small skids or wheels to protect the wing tips from ground contact. In most high performance gliders the undercarriage can be raised to reduce drag in flight and lowered for landing. Wheel brakes are provided to allow stopping once on the ground. These may be engaged by fully extending the spoilers/air-brakes or by using

1710-439: The descent to reach the touchdown point. This gives the pilot wide safety margins should unexpected events occur. If such control devices are not sufficient, the pilot may utilize maneuvers such as a forward slip to further steepen the glider slope. Most gliders require assistance to launch, though some have an engine powerful enough to launch unaided. In addition, a high proportion of new gliders have an engine which will sustain

1767-401: The ends of the wings decrease drag and so improve wing efficiency. Special aerodynamic seals are used at the ailerons , rudder and elevator to prevent the flow of air through control surface gaps. Turbulator devices in the form of a zig-zag tape or multiple blow holes positioned in a span-wise line along the wing are used to trip laminar flow air into turbulent flow at a desired location on

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1824-412: The first glider pilot to use an updraft rising along a mountain slope to stay aloft for a lengthy period. He then founded the world's first glider pilot school at the Wasserkuppe. The first competition was organised by Oskar Ursinus , who also built the first clubhouse on the Wasserkuppe in 1924 to replace the shipping containers that enthusiasts were using as accommodation up to that point. By 1930,

1881-695: The following extreme values: Students from the Darmstadt University of Technology , then known as Technische Hochschule Darmstadt , began flying gliders from the Wasserkuppe as early as 1911, but interest in gliding in Germany increased greatly after 1918 when the Treaty of Versailles restricted the production or use of powered aircraft in the nation. From 1920 onwards, annual gliding competitions were held, leading to records being set and broken for height, distance and duration of unpowered flight. In 1922 Arthur Martens  [ de ] became

1938-558: The glass-fiber Libelle of the 1960s increased that to 36:1, and modern flapped 18 meter gliders such as the ASG29 have a glide ratio of over 50:1. The largest open-class glider, the Eta , has a span of 30.9 meters and has a glide ratio over 70:1. Compare this to the Gimli Glider , a Boeing 767 which ran out of fuel mid-flight and was found to have a glide ratio of 12:1, or to

1995-622: The glider in the air, but is insufficiently powerful to launch the glider. Compared with self-launchers these lower powered engines have advantages in weight, lower costs and pilot licensing. The engines can be electric, jet, or two-stroke gasoline. Gliders in continental Europe use metric units, like km/h for airspeed and m/s for lift and sink rate . In the United States, United Kingdom, Australia and some other countries gliders use knots and ft / min in common with commercial aviation worldwide. In addition to an altimeter , compass , and an airspeed indicator , gliders are often equipped with

2052-409: The glider to Earth in a short distance. Early glider designs used skids for landing, but modern types generally land on wheels. Some of the earliest gliders used a dolly with wheels for taking off and the dolly was jettisoned as the glider left the ground, leaving just the skid for landing. A glider may be designed so the center of gravity (CG) is behind the main wheel so the glider sits nose high on

2109-427: The glider. In powered aircraft, this is done by reducing engine thrust. In gliders, other methods are used to either reduce the lift generated by the wing, increase the drag of the entire glider, or both. Glide slope is the distance traveled for each unit of height lost. In a steady wings-level glide with no wind, glide slope is the same as the lift/drag ratio (L/D) of the glider, called "L-over-D". Reducing lift from

2166-531: The ground. Other designs may have the CG forward of the main wheel so the nose rests on a nose-wheel or skid when stopped. Skids are now mainly used only on training gliders such as the Schweizer SGS 2–33 . Skids are around 100 millimetres (4 in) wide by 900 mm (3 ft) long and run from the nose to the main wheel. Skids help with braking after landing by allowing the pilot to put forward pressure on

2223-462: The improvements in aerodynamics , the performance of gliders has increased. One measure of performance is the glide ratio . A ratio of 30:1 means that in smooth air a glider can travel forward 30 meters while losing only 1 meter of altitude. Comparing some typical gliders that might be found in the fleet of a gliding club – the Grunau Baby from the 1930s had a glide ratio of just 17:1,

2280-534: The past many gliders were not. These types did not soar . They were simply engine-less aircraft towed by another aircraft to a desired destination and then cast off for landing. The prime example of non-soaring gliders were military gliders (such as those used in the Second World War). They were often used just once and then usually abandoned after landing, having served their purpose. Motor gliders are gliders with engines which can be used for extending

2337-568: The pilot can switch the engine on and off in flight without retracting the propeller. 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 first built for sporting purposes in Germany. Germany's strong links to gliding were to

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2394-413: The problem of how fast a pilot should cruise between thermals, given both the average lift the pilot expects in the next thermal climb, as well as the amount of lift or sink encountered in cruise mode. Electronic variometers make the same calculations automatically, after allowing for factors such as the glider's theoretical performance , water ballast, headwinds/tailwinds and insects on the leading edges of

2451-485: The range achievable in direct sun on a hot day. Color is not used except for a few small bright patches on wing tips; these patches (typically orange or red) improving a glider's visibility to other airborne aircraft. Such patches are obligatory for mountain flying in France. Non-fibreglass gliders made of aluminum or wood are not so subject to deterioration at higher temperatures and are often quite brightly painted. There

2508-503: The river Lütter which joins the Fulda after 50 kilometres (31 mi). The other peaks near the Wasserkuppe are Abtsrodaer Kuppe (north, 905 metres (2,969 ft) NN), Schafstein  [ de ] (east, 831.8 metres (2,729 ft) NN) and Pferdskopf (south west, 874.9 metres (2,870 ft) NN). Wasserkuppe's climate is classified as humid continental ( Köppen : Dfb ; Trewartha : Dclo ) closely bordering on

2565-456: The sailplane is towed behind a powered aircraft using a rope about 60 metres (200 ft) long. The sailplane pilot releases the rope after reaching the desired altitude. However, the rope can be released by the towplane also in case of emergency. Winch launching uses a powerful stationary engine located on the ground at the far end of the launch area. The sailplane is attached to one end of 800 to 1,200 metres (2,600 to 3,900 ft) of cable and

2622-649: The state, and for Hitler Youth pilots and their instructors, proficiency in gliding was viewed as the first step towards the Luftwaffe . Sailplane research was also nationalised under the Deutsche Forschungsanstalt für Segelflug (DFS – German Research Institute for Sailplane Flight). Following World War II , a US Air Force base, radar station, and surveillance station were established there but when restrictions on German aviation were lifted in 1951, gliding soon returned to

2679-399: The strength of the lift or sink, so that the pilot can concentrate on centering a thermal, watching for other traffic, on navigation, and weather conditions. Rising air is announced to the pilot as a rising tone, with increasing pitch as the lift increases. Conversely, descending air is announced with a lowering tone, which advises the pilot to escape the sink area as soon as possible. (Refer to

2736-762: The three principal companies are: Germany also has Stemme and Lange Aviation . Elsewhere in the world, there are other manufacturers such as Jonker Sailplanes in South Africa, Sportinė Aviacija in Lithuania, Allstar PZL in Poland, Let Kunovice and HpH in the Czech Republic and AMS Flight in Slovenia. Wasserkuppe The German name is derived from Wasenkuppe, Asenberg or Weideberg and means Pasture mountain . The Wasserkuppe lies in

2793-707: The underside of a single wing, and also on the fin and rudder . Registration marks are assigned by gliding associations such as the US Soaring Society of America , and are unrelated to national registrations issued by entities such as the US Federal Aviation Administration . This need for visual ID has somewhat been supplanted by GPS position recording. Insignias are useful in two ways: First, they are used in radio communications between gliders, as pilots use their competition number as their call signs . Secondly, to easily tell

2850-647: The upper wing surfaces during slow flight and Schreder and the HP-15 finished in 65th place. After the Championships Schreder re-winged the fuselage to produce his next design, the HP-16 . In the April 2011 the sole HP-15 prototype, registered N5488, still existed and was privately registered in Peoria, Illinois . General characteristics Performance This article on an aircraft of

2907-423: The water ballast is advantageous if the lift is likely to be strong, and may also be used to adjust the glider's center of mass . Moving the center of mass toward the rear by carrying water in the vertical stabilizer reduces the required down-force from the horizontal stabilizer and the resultant drag from that down-force. Although heavier gliders have a slight disadvantage when climbing in rising air, they achieve

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2964-448: The winch rapidly winds it in. The sailplane can gain about 270 to 910 metres (900 to 3,000 ft) of height with a winch launch, depending on the headwind. Less often, automobiles are used to pull sailplanes into the air, either by pulling them directly or through the use of a reverse pulley in a similar manner to the winch launch. Elastic ropes (known as bungees ) are occasionally used at some sites to launch gliders from slopes, if there

3021-400: The wing. This flow control prevents the formation of laminar flow bubbles and ensures the absolute minimum drag. Bug-wipers may be installed to wipe the wings while in flight and remove insects that are disturbing the smooth flow of air over the wing. Modern competition gliders carry jettisonable water ballast (in the wings and sometimes in the vertical stabilizer). The extra weight provided by

3078-465: The wings and/or increasing drag will reduce the L/D allowing the glider to descend at a steeper angle with no increase in airspeed. Simply pointing the nose downwards only converts altitude into a higher airspeed with a minimal initial reduction in total energy. Gliders, because of their long low wings, create a high ground effect which can significantly increase the glide angle and make it difficult to bring

3135-643: The wings. Soaring flight computers running specialized soaring software, have been designed for use in gliders. Using GPS technology in conjunction with a barometric device these tools can: After the flight the GPS data may be replayed on computer software for analysis and to follow the trace of one or more gliders against a backdrop of a map, an aerial photograph or the airspace. So that ground-based observers may identify gliders in flight or in gliding competition , registration marks ("insignias" or "competition numbers" or "contest ID") are displayed in large characters on

3192-536: Was opened on the plateau, with Neil Armstrong a guest of honour at the ceremony. The museum gained a new building in 1987. The Wasserkuppe is also the home of the Oldtimer Segelflugclub (OSC – Oldtimer Gliding Club), dedicated (as its name suggests) to flying vintage sailplanes . Next to the long tradition of sailplanes the Wasserkuppe has become a sports and weekend centre offering a wide selection of activities. Paragliding as well as Snowkiting

3249-547: 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. Flaps are fitted to the trailing edges of the wings on some gliders to optimise lift and drag at a wide range of speeds. With each generation of materials and with

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