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75-591: It is one of several Air Sport Commissions (ASC) of the Fédération Aéronautique Internationale (FAI), or "World Air Sports Federation". FAI is the world body for sporting aviation and the certification of world records for aeronautics and astronautics and was founded in 1905. When the IGC was founded in 1932, it was called CIVV (Commission Internationale de Vol à Voile) and has also been called CVSM (Commission de Vol Sans Moteur). It

150-566: A couple of decades of small, incremental performance gains, the appearance in 2000 of the eta brought a sudden jump in performance and a further price escalation. This very expensive aircraft has up to now not had outstanding success in competition, but it for a while seemed to impact the cost of remaining competitive in the class. The 'eta biter' and its successor, the Concordia single-seater, as well as Walter Binder's EB28 / EB29 until 2012 were being presented as challengers to eta, but

225-536: A favourite testing ground for technological innovation. Many research prototypes fall under this class definition, e.g. the Akaflieg Darmstadt D-30 of 1938, which had variable-dihedral wings and spars built of light alloys, the extremely large-span SB-10 of 1972, the telescoping-wing Akaflieg Stuttgart FS-29 of 1975 and the solar-powered Icare . In contests, the Open Class usually delivers

300-531: A feature of all World and European Championships. Technological development has eroded the performance gap that once existed between the Standard and 15-metre classes, which today is perceptible only in strong gliding weather. Some observers argue that the difference is not meaningful enough, that the 18 metre class is the natural successor to the 15 metre class and that the latter should be removed from World Championships to give space to new classes. Notwithstanding,

375-409: A gallery around the base of the balloon rather than the hanging basket of the first, unmanned design, which brought the paper closer to the fire. On their free flight, De Rozier and d'Arlandes took buckets of water and sponges to douse these fires as they arose. On the other hand, the manned design of Charles was essentially modern. As a result of these exploits, the hot air balloon became known as

450-435: A given weight by the application of power to the resistance of air." He identified the four vector forces that influence an aircraft: thrust , lift , drag and weight and distinguished stability and control in his designs. He developed the modern conventional form of the fixed-wing aeroplane having a stabilising tail with both horizontal and vertical surfaces, flying gliders both unmanned and manned. He introduced

525-415: A glider for either 300 meters or 30 seconds, and "B" level if they made two flights of 45 seconds in straight lines plus one of 60 seconds in an "S" pattern. (It should be remembered that these flights were made by bungee cord launches down hillsides.) In time a "C" level, requiring a five-minute flight, was added. A few years later Fritz Stamer, chief flight instructor of an early gliding school, designed

600-602: A low-cost sailplane, which should have moderate performance, be easy to assemble and to handle, and safe for inexperienced pilots to fly. The idea behind the project was to make gliding competitions more affordable and popular. The winning design was announced in 1993 as the Warsaw Polytechnic PW-5 , thus becoming the only glider allowed to take part in the competition. The first World Class World Championship took place in 1997 in Inonu , Turkey , but participation

675-693: A major fraction of the drag of sleek fibreglass airframes. Designers reacted by recessing the wheels into the fuselage, which further increased the risk of ground-related damage. Manufacturers took to arguing that the single cheapest way to increase performance was to retract the wheel. In view of these safety and cost-related arguments, the Standard Class rules were updated to allow disposable water ballast and retractable undercarriages. Retractable wheels were allowed by 1970 and water ballast by 1972. Manufacturers were fitting these as production items, and they had to be disabled to fly in competitions. In 1965

750-489: A modern Two Seater Class with a span limitation of 20 metres and maximum all-up weight of 800 kg. This class has no relationship to the 'old' two-seater class, as it targets the high performance trainers that have been steadily gaining in popularity. Their smaller size sets them apart from the Open Class two-seaters which are very expensive and require experienced crews. The 20 metre two-seaters handle and fly more like Standard Class single-seaters and cost little more than half

825-438: A particularly remarkable performance in gliding, or eminent services to the sport of gliding over a long period of time". The first recipient was Tadeusz Góra in recognition of his 577.8 km flight. Its recipients include: Aeronautics Aeronautics is the science or art involved with the study, design , and manufacturing of air flight -capable machines, and the techniques of operating aircraft and rockets within

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900-461: A pressure altitude sensor and a Global Navigation Satellite System ( GNSS ) receiver. Data output is in a standard ASCII-based format, the "IGC flight data format". This is used in files with the suffix "IGC" that is specified in detail in Appendix A of the document "Technical Specification for IGC-approved GNSS Flight Recorders". Organisations outside IGC also use IGC-approved flight recorders and

975-464: A security code in the downloaded file of flight data. This code and the file data itself can be checked ("validated") at any time later using a validation program that is posted on the IGC GNSS web site. This validation program checks three things: A public/private key (PPK) encryption system such as RSA or equivalent is used to achieve the validation process above. IGC-approved Recorders also have

1050-495: A security device such as a microswitch that operates if the recorder is opened. This enables unauthorised modification to the recorder to be detected and protects the integrity of its output data. There are three levels of IGC-approval: These are allocated by GFAC depending on factors such as the security of the type of FR with respect to the latest IGC FR Specification, the age of the FR design and experience of its characteristics, and

1125-485: A similar demonstration of a hydrogen balloon. Charles and two craftsmen, the Robert brothers, developed a gas-tight material of rubberised silk for the envelope. The hydrogen gas was to be generated by chemical reaction during the filling process. The Montgolfier designs had several shortcomings, not least the need for dry weather and a tendency for sparks from the fire to set light to the paper balloon. The manned design had

1200-426: Is a branch of dynamics called aerodynamics , which deals with the motion of air and the way that it interacts with objects in motion, such as an aircraft. Attempts to fly without any real aeronautical understanding have been made from the earliest times, typically by constructing wings and jumping from a tower with crippling or lethal results. Wiser investigators sought to gain some rational understanding through

1275-522: Is a significant factor in the decline of the World Class, as it is equally affordable, yields higher performances and allows a degree of personal choice in equipment that does not exist in the World Class. The International Gliding Commission (IGC/CIVV) which is part of the FAI and an associated body called Organisation Scientifique et Technique du Vol à Voile (OSTIV) announced a competition in 1989 for

1350-487: Is a valuable check that both systems are working correctly. In March 1995, IGC created the "GNSS FR Approval Committee" (GFAC) to test recorders and co-ordinate IGC rules, and Annex B to the Sporting Code for gliders (SC3B) was created for FR rules and procedures. GFAC also issues IGC-approval documents for approved types of FR that are posted on the IGC GNSS web site. For IGC-approval, the recorder design includes

1425-607: Is considered to be the first air plane in series production, making the Maschinenfabrik Otto Lilienthal in Berlin the first air plane production company in the world. Otto Lilienthal is often referred to as either the "father of aviation" or "father of flight". Other important investigators included Horatio Phillips . Aeronautics may be divided into three main branches, Aviation , Aeronautical science and Aeronautical engineering . Aviation

1500-418: Is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction . Rocket engines push rockets forwards simply by throwing their exhaust backwards extremely fast. Rockets for military and recreational uses date back to at least 13th-century China . Significant scientific, interplanetary and industrial use did not occur until the 20th century, when rocketry

1575-530: Is the Ka 6 . Technological change was fast-paced in the years following the introduction of the Standard Class. The transition to fibreglass construction made the existing rules increasingly awkward. The stronger composite structures allowed higher wing loadings, and competitors resorted to fixed ballast to exploit this competitive advantage, which of course increased landing speeds and the risk of damage when alighting in unprepared fields. The fixed undercarriages caused

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1650-572: Is the FAI commission responsible for the international competitions, records and badges that apply to gliders and motor gliders . The term "sailplanes" is sometimes used. Hang gliders and paragliders have a separate body called the FAI CIVL Commission, which stands for "Commission Internationale de Vol Libre". The World Gliding Championships are organised every two years or so by the FAI Gliding Commission and

1725-421: Is the art or practice of aeronautics. Historically aviation meant only heavier-than-air flight, but nowadays it includes flying in balloons and airships. Aeronautical engineering covers the design and construction of aircraft, including how they are powered, how they are used and how they are controlled for safe operation. A major part of aeronautical engineering is aerodynamics , the science of passing through

1800-467: Is understood to exclude the current state-of-the-art gliders. Water ballast is not permitted. The class is perceived as being fair in spite of the differences in glider performance. This may become compromised by the trend towards modification/customisation of Club Class gliders in ways that distort the handicapping and are difficult to control by the sporting bodies. The emergence of the Club Class

1875-553: The Montgolfière type and the gas balloon the Charlière . Charles and the Robert brothers' next balloon, La Caroline , was a Charlière that followed Jean Baptiste Meusnier 's proposals for an elongated dirigible balloon, and was notable for having an outer envelope with the gas contained in a second, inner ballonet. On 19 September 1784, it completed the first flight of over 100 km, between Paris and Beuvry , despite

1950-461: The atmosphere . While the term originally referred solely to operating the aircraft, it has since been expanded to include technology, business, and other aspects related to aircraft. The term " aviation " is sometimes used interchangeably with aeronautics, although "aeronautics" includes lighter-than-air craft such as airships , and includes ballistic vehicles while "aviation" technically does not. A significant part of aeronautical science

2025-676: The 15 and 18 metre classes with interchangeable wing tips: the AS 33 (2020), the Ventus-3 (2016), and the JS-3 (2017). A two-seater class appeared for the first time in a World Championships in 1952. The reason for having a separate class was that the drag of the larger fuselage put two-seaters at a significant disadvantage vis-à-vis single seaters. This class was discontinued after the 1956 World Championships, although two-seater World records were retained until 1996. The IGC voted in 2005 to reinstate

2100-406: The 17th century with Galileo 's experiments in which he showed that air has weight. Around 1650 Cyrano de Bergerac wrote some fantasy novels in which he described the principle of ascent using a substance (dew) he supposed to be lighter than air, and descending by releasing a controlled amount of the substance. Francesco Lana de Terzi measured the pressure of air at sea level and in 1670 proposed

2175-593: The American Richard Schreder flew a variant of his HP-11 , which in normal form had simple flaps as airbrakes. To comply with the rules, the ship was modified for the World Championships so that the outer half of the flaps hinged upwards to comply with the rules. Schreder pointed out that this made the glider more expensive and less safe (higher landing speed, less effective brakes). The argument over whether to allow this went on for

2250-528: The Chinese techniques then current. The Chinese also constructed small hot air balloons, or lanterns, and rotary-wing toys. An early European to provide any scientific discussion of flight was Roger Bacon , who described principles of operation for the lighter-than-air balloon and the flapping-wing ornithopter , which he envisaged would be constructed in the future. The lifting medium for his balloon would be an "aether" whose composition he did not know. In

2325-533: The D badge became known as the Silver C, and more often today just the Silver Badge. Earning the Silver Badge shows that a glider pilot has achieved an altitude gain of at least 1,000 m, made a five-hour duration flight, and has flown cross-country for a straight-line distance of at least 50 km: these three attainments are usually, but not invariably, achieved in separate flights. The first recipients of

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2400-617: The Diamond Badge) started in 1949. The Diamond Badge requires three achievements: flying 300 km to a pre-defined goal, going 500 km in one flight (but not necessarily to a pre-defined goal), and gaining 5,000 m in height. Earning all three "diamonds" qualifies the pilot for the FAI registry as a Diamond Badge holder. The first pilot with the Diamond Badge was the American, John Robinson, in 1950, who had also held

2475-438: The FAI under sub-classes that do not have a one-to-one correspondence with the above competition classes: Glider classes not recognised by the FAI have been used in some regional and national competitions. The most significant of these are: The Open Class is the oldest competition class, although it only came into formal existence with the creation of the two-seater class in the early 1950s. This unrestricted class has been

2550-585: The Gold C and now usually just the Gold Badge) was established in 1935. A pilot who has completed the Gold Badge has flown 300 km, though not necessarily to a pre-defined goal, gained 3,000 m in height and has made a five-hour flight (only one has to be done to count for both the Silver and Gold). Up to this level the badges are registered only by the national gliding associations. The F Badge (now

2625-416: The IGC flight data file format. In IGC-approved recorders, GNSS and pressure altitude data is continuously recorded during flight in fixes stored in non-volatile memory inside the recorder. Typical fix intervals, set by the pilot before flight, are 5 seconds for "cruising" flight between turn points, and 1 second near turn points or other points of interest. Pressure altitude figures must be calibrated to

2700-522: The International pressure/altitude values of the ICAO ISA (International Standard Atmosphere). Re-calibrations to check any errors from the ICAO ISA are carried out at regular intervals. GNSS lat/long data records the track over ground and in particular whether a particular turn point (TP) has been reached. GNSS altitude data can be compared with pressure altitude data from the recorder and this

2775-503: The Silver C were Wolf Hirth and Robert Kronfeld on 15 February 1931. In 1932 the FAI recognized gliding, and formed a new section: the Commission Internationale de Vol à Voile (CIVV). This eventually took over the role of ISTUS. The FAI decided that the Silver C was sufficiently meritorious to be internationally recognised, and issued the first 300 before turning the awarding over to the national societies. From

2850-668: The Standard and 15 metre classes. Some significant Standard Class types have been the Ka 6 and Mucha (1958), the LS1 (1967), the Standard Cirrus (1969), the LS4 (1980) and the Discus (1984). Modern contenders include the Discus 2 (1998), LS8 (1995) and ASW 28 (2000) This class was created specifically to end the trailing-edge airbrake controversy in the Standard Class. The class has been very successful, being since its inception

2925-648: The absolute altitude record. Over 7600 people have achieved this level. The FAI also issues a diploma for a flight of 750 km, and additional ones in increments of 250 km, maintaining lists of the holders of these awards. As of 2019 six people had been awarded a 2000 km diploma The wide variety of records have been defined by the FAI Gliding Commission. The classes of glider have been combined into four groups: Open, 15 metre, World Class and Ultralight. Although female pilots can claim world records in these general categories, there are also additional records in these categories just for female pilots. Because of

3000-511: The air as the air does to the object." ( Newton would not publish the Third law of motion until 1687.) His analysis led to the realisation that manpower alone was not sufficient for sustained flight, and his later designs included a mechanical power source such as a spring. Da Vinci's work was lost after his death and did not reappear until it had been overtaken by the work of George Cayley . The modern era of lighter-than-air flight began early in

3075-405: The air becomes compressed, typically at speeds above Mach 1. Transonic flow occurs in the intermediate speed range around Mach 1, where the airflow over an object may be locally subsonic at one point and locally supersonic at another. A rocket or rocket vehicle is a missile , spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine . In all rockets, the exhaust

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3150-544: The air. With the increasing activity in space flight, nowadays aeronautics and astronautics are often combined as aerospace engineering . The science of aerodynamics deals with the motion of air and the way that it interacts with objects in motion, such as an aircraft. The study of aerodynamics falls broadly into three areas: Incompressible flow occurs where the air simply moves to avoid objects, typically at subsonic speeds below that of sound (Mach 1). Compressible flow occurs where shock waves appear at points where

3225-481: The appearance and performance of shorter wingspan competitors in World Gliding Championships of 2012 may change established views on the design trends. In July 2007, the IGC increased the maximum weight allowed in the Open Class to 850 kg provided the aircraft has a valid certificate of airworthiness at that weight, i.e. the manufacturers must re-certify the glider. The Standard Class

3300-585: The beginning the lesser badges were only recorded by local gliding associations, and their criteria varies, although they are usually integrated into organized training programs. For example, in the United States a Bronze Badge is issued for demonstrated pre-cross country flying skills beyond the C level. In Britain a pilot progresses from the B to the Bronze level and then receives an additional endorsement for cross-country training. The E badge (later called

3375-515: The class and created a parallel 15 metre Class to accommodate them. This decision was polemic as it was the second rule change in a few years and it orphaned several glider types that did not fit well within either class definition (especially the PIK-20 and the Libelle that had been built in large numbers). Notwithstanding, the decision was vindicated by the great success subsequently enjoyed by both

3450-706: The class has a sizeable following and official support into the foreseeable future. Significant 15 metre types include the ASW 20 (1977), Ventus (1980), LS6 (1983). Modern contenders include the Ventus-2 (1994), the ASW-27 (1995) and Diana 2 (2005). The availability of carbon fibre at affordable prices has allowed the manufacture of light and economical spans exceeding 15 metres. Manufacturers started to exploit this potential by offering tip extensions for their flapped sailplanes. Spans increased gradually from 16.6 metres in

3525-493: The classes have not been targeted at fostering technological development as in other sports. Instead classes have arisen because of: The FAI Gliding Commission (IGC) is the sporting body overseeing air sports at the international level so that essentially the same classes and class definitions are followed in all countries. Seven glider classes are currently recognised by the FAI and are eligible for European and World Championships : Gliding World Records are classified by

3600-459: The demarcation line between airbrake/landing flaps and performance enhancing flaps is vague. The reluctance within the IGC to allow the later in the Standard Class led to an unsuccessful attempt to codify what constitutes a landing flap. After the LS2 and the PIK-20 exploited this loophole to win the 1974 and 1976 World Championships in the Standard Class, the IGC banned all camber-changing devices from

3675-445: The first implementations ( ASW 20L and Ventus b 16.6 ) to 17 metres ( DG-200/17 , DG-600 , Glasflügel 403 ), 17.5 metres ( LS6-c ), finally settling on 18 metres. The trend towards turbo and self-launching sailplanes also favours the 18 metre span, which is large enough to carry the additional weight of the power unit without impairing the ability to climb in weak lift. Following a decade of contests at regional level, which permitted

3750-546: The first scientifically credible lifting medium in the form of hollow metal spheres from which all the air had been pumped out. These would be lighter than the displaced air and able to lift an airship . His proposed methods of controlling height are still in use today; by carrying ballast which may be dropped overboard to gain height, and by venting the lifting containers to lose height. In practice de Terzi's spheres would have collapsed under air pressure, and further developments had to wait for more practicable lifting gases. From

3825-573: The gull insignia which were used for these awards and later for the badges. ISTUS (Internationale Studienkommission für motorlosen Flug) , was founded in Frankfurt on 13 June 1930, to record international gliding achievements. The founding nations were Belgium, France, the Netherlands, Hungary, Germany, Italy, and the USA. A series of badges for solo gliding was devised called A, B, C, D etc. Later

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3900-710: The host nation. Within FAI, the sport of glider aerobatics is managed by the FAI Aerobatics Commission (CIVA), which stands for "Commission Internationale de Voltige Aérienne" and also deals with powered-aircraft aerobatics In the early 1920s two flying organizations, the Association of the German Model and Gliding Clubs, and the Rhön Soaring Association , determined that pilots would be listed as "A" level if they flew

3975-429: The idea of " heavier than air " a reality. Newspapers and magazines published photographs of Lilienthal gliding, favourably influencing public and scientific opinion about the possibility of flying machines becoming practical. His work lead to him developing the concept of the modern wing. His flight attempts in Berlin in the year 1891 are seen as the beginning of human flight and the " Lilienthal Normalsegelapparat "

4050-412: The integrity of FR flight data and its resistance to "hacking". An associated body is Organisation Scientifique et Technique du Vol à Voile (OSTIV) which facilitates contact between glider manufacturers and pilots to share experience and opinion The Commission makes awards for great achievements and meritorious service. For gliding it presents: The Lilienthal Medal was instituted in 1938 "to reward

4125-453: The late fifteenth century, Leonardo da Vinci followed up his study of birds with designs for some of the earliest flying machines, including the flapping-wing ornithopter and the rotating-wing helicopter . Although his designs were rational, they were not based on particularly good science. Many of his designs, such as a four-person screw-type helicopter, have severe flaws. He did at least understand that "An object offers as much resistance to

4200-475: The man-powered propulsive devices proving useless. In an attempt the next year to provide both endurance and controllability, de Rozier developed a balloon having both hot air and hydrogen gas bags, a design which was soon named after him as the Rozière. The principle was to use the hydrogen section for constant lift and to navigate vertically by heating and allowing to cool the hot air section, in order to catch

4275-519: The mid-18th century the Montgolfier brothers in France began experimenting with balloons. Their balloons were made of paper, and early experiments using steam as the lifting gas were short-lived due to its effect on the paper as it condensed. Mistaking smoke for a kind of steam, they began filling their balloons with hot smoky air which they called "electric smoke" and, despite not fully understanding

4350-436: The most common type of rocket and they typically create their exhaust by the combustion of rocket propellant . Chemical rockets store a large amount of energy in an easily released form, and can be very dangerous. However, careful design, testing, construction and use minimizes risks. Glider competition classes Competition classes in gliding , as in other sports, mainly exist to ensure fairness in competition. However

4425-411: The most favourable wind at whatever altitude it was blowing. The balloon envelope was made of goldbeater's skin . The first flight ended in disaster and the approach has seldom been used since. Sir George Cayley (1773–1857) is widely acknowledged as the founder of modern aeronautics. He was first called the "father of the aeroplane" in 1846 and Henson called him the "father of aerial navigation." He

4500-428: The next five years in IGC and eventually the rules were changed to permit plain flaps provided they were the only means of drag control for landing, and there was no aileron linking for camber changing. There were no other limits on using the flaps for lift increase (although the lack of aileron linking meant that the flaps were not as effective as they might have been). A later concession would bring difficulties in that

4575-415: The number of entrants is not large enough to warrant their separation into the usual classes. The formal recognition by the FAI of a handicapped class is quite recent, with the first Club Class World Championships having taken place in 2001. It is intended by the FAI as an affordable entry-level class. It has been extremely successful, attracting some of the most talented and experienced pilots in addition to

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4650-755: The number of records the table below only summarises some of the Open Category gliding records as at the beginning of 2008. A full list is available on the FAI web site. With the advent of satellite navigation equipment at an affordable price, the International Gliding Commission of FAI developed a technical specification for approved flight recorders. IGC-approved flight recorders provide precise evidence of position for gliding competitions , national and world records. They replace photographic evidence or ground-based observers to record aircraft position. IGC-approved recorders include

4725-593: The price of an Open Class glider. Gliders in this class include the Duo Discus (unflapped), Arcus (flapped), ASG 32 , and the DG-1000 , with the older Janus and DG-500 also being eligible. Handicapped contests have been a long-standing feature of many regional and national level events. These Club or sports contests allow the use of gliders of widely differing levels of performance. They are thus popular in places where mostly older types are available, or where

4800-635: The principles at work, made some successful launches and in 1783 were invited to give a demonstration to the French Académie des Sciences . Meanwhile, the discovery of hydrogen led Joseph Black in c.  1780 to propose its use as a lifting gas, though practical demonstration awaited a gas-tight balloon material. On hearing of the Montgolfier Brothers' invitation, the French Academy member Jacques Charles offered

4875-535: The resolution of issues such as mixed glider/motorglider competition, this class came to feature for the first time in a World Championships in 2001, with a maximum all-up weight of 600 kg. Significant 18 metre types include the Schleicher ASG 29 (2005), Schempp-Hirth Ventus-2 (1995), and the Jonker JS-1 (2007). The same three manufacturers have since introduced new types which are competitive in both

4950-526: The study of bird flight. Medieval Islamic Golden Age scientists such as Abbas ibn Firnas also made such studies. The founders of modern aeronautics, Leonardo da Vinci in the Renaissance and Cayley in 1799, both began their investigations with studies of bird flight. Man-carrying kites are believed to have been used extensively in ancient China. In 1282 the Italian explorer Marco Polo described

5025-567: The top performances, with daily tasks as far as 1000 km being possible in favourable weather. To be successful, however, an Open Class glider must blend high performance with practicality. "Extreme" designs tend to be failures, of which the Austria of 1931, the Sigma of 1971 and the BJ series are but the most conspicuous examples. Arguably the only 'extreme' glider that ever won a World Championships

5100-422: The use of the whirling arm test rig to investigate the aerodynamics of flight, using it to discover the benefits of the curved or cambered aerofoil over the flat wing he had used for his first glider. He also identified and described the importance of dihedral , diagonal bracing and drag reduction, and contributed to the understanding and design of ornithopters and parachutes . Another significant invention

5175-430: The young and impecunious. Among the reasons for this are the long lifespans of gliders that invite their continued use, the relative simplicity of the class rules and the typically more relaxed "atmosphere" of Club Class competitions. The glider types allowed are not explicitly defined. The criterion for admission is given by an interval of performance handicaps which may be adjusted by the organisers of each event but that

5250-407: Was introduced in the late fifties as an alternative to the increasingly heavy, difficult to fly and costly Open Class ships of that time. Striving for affordability and simplicity, the original standard class rules restricted the span to 15 metres and ruled out retractable undercarriages, flight-disposable ballast, radios and lift-enhancing devices such as flaps. The archetypal embodiment of these rules

5325-650: Was not as high as has been expected. World Class world championships have ceased after 1 October 2014. This class will be replaced by a 13.5 metre Class in which more types of gliders with disposable ballast will be permitted. First World gliding championship of the 13.5 metre Class took place in August 2015 in Lithuania. A glider with a take-off mass not exceeding 220 kg is in the DU Ultralight Class. This class has been defined for world records but there

5400-676: Was the Nimbus I . Until the 1960s, a fair number of gliders were able to do well in open competition, with smaller-span types occasionally beating larger but more cumbersome types. The composite revolution caused a shake-down, further aggravated when the ASW 22 and Nimbus-3 were introduced in 1981, after which the Open Class for a while became the exclusive preserve of only two manufacturers. The World Gliding Championships of 2012 brought into competition new designs, some of significantly lower wingspan, which flew successfully against "traditional" (wingspan 28 m+) machines of this class. Following

5475-586: Was the enabling technology of the Space Age , including setting foot on the Moon . Rockets are used for fireworks , weaponry, ejection seats , launch vehicles for artificial satellites , human spaceflight and exploration of other planets. While comparatively inefficient for low speed use, they are very lightweight and powerful, capable of generating large accelerations and of attaining extremely high speeds with reasonable efficiency. Chemical rockets are

5550-411: Was the first true scientific aerial investigator to publish his work, which included for the first time the underlying principles and forces of flight. In 1809 he began the publication of a landmark three-part treatise titled "On Aerial Navigation" (1809–1810). In it he wrote the first scientific statement of the problem, "The whole problem is confined within these limits, viz. to make a surface support

5625-443: Was the tension-spoked wheel, which he devised in order to create a light, strong wheel for aircraft undercarriage. During the 19th century Cayley's ideas were refined, proved and expanded on, culminating in the works of Otto Lilienthal . Lilienthal was a German engineer and businessman who became known as the "flying man". He was the first person to make well-documented, repeated, successful flights with gliders , therefore making

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