The Wasserkuppe is a mountain within the German state of Hesse. The elevation, a large plateau formation, is the highest peak in the Rhön Mountains. Between the First and Second World Wars great advances in sailplane development took place on the mountain during the interwar period. Near the summit there is still an airfield used by gliding pilots of light aircraft; the German name means Pasture mountain. The Wasserkuppe lies in the administrative district Fulda 5.3 kilometres north of Gersfeld. Other villages nearby are Wüstensachsen, it is part of the Rhön Biosphere Reserve. The Wasserkuppe sources the spring of the river Fulda and the river Lütter which joins the Fulda after 50 kilometres; the other peaks near the Wasserkuppe are Abtsrodaer Kuppe and Pferdskopf. Students from the Darmstadt University of Technology known as Technische Hochschule Darmstadt, began flying gliders from the Wasserkuppe as early as 1911, but interest in gliding in Germany increased 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 and duration of unpowered flight. In 1922 Arthur Martens became the first glider pilot to use an updraft rising along a mountain slope to stay aloft for a lengthy period, he founded the world's first glider pilot school at the Wasserkuppe. The first competition was organised by Oskar Ursinus, who 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, the competition had become an international event, drawing pilots from all over Europe and the United States. In 1924'Rhönvater' Oskar Ursinus convinced the secretary of air transport for the ministry of transportation Ernst Brandenburg to turn the new gliding club into a state funded research organization; this started the Rhön-Rossitten Gesellschaft and as 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. Every German aeronautical engineer and test pilot of note during the 1920s and 1930s spent time building and flying aircraft at the Wasserkuppe, including the Günter brothers, Wolf Hirth, the Horten brothers, Robert Kronfeld, Hans Jacobs, Heini Dittmar, Alexander Lippisch, Willy Messerschmitt, Hanna Reitsch, Peter Riedel, Alexander Schleicher and many, many others; this period saw great advances in new technologies such as rocket-powered flights. In the 1930s the "Ehrenhalle" 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 tomb. It is a memorial to all pilots; the inscription on the memorial is Lilienthal's famous last words: "Opfer müssen gebracht werden" meaning: "Sacrifices must be made." During the Third Reich, gliding activities became controlled by the state, for Hitler Youth pilots and their instructors, proficiency in gliding was viewed as the first step towards the Luftwaffe.
Sailplane research was nationalised under the Deutsche Forschungsanstalt für Segelflug. Following World War II, a US Air Force base, radar station, surveillance station were established there but when restrictions on German aviation were lifted in 1951, gliding soon returned to the Wasserkuppe where it has remained popular since. Beginning in the 1970s, the newer sport of hang gliding has 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 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 the home of the Oldtimer Segelflugclub, dedicated 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 is offered. In winter the area is used by snowboarders. RRG Fafnir RRG Professor RRG Urubu Obs Rhön-Rossitten Gesellschaft Stratobowl, a similar bowl-shaped natural landform in the United States, associated with historic aviation activity Media related to Wasserkuppe at Wikimedia Commons Oldtimer Segelflugclub Pilot school at the Wasserkuppe hourly updated Webcam picture of the Airfield at the Wasserkuppe taken from pilot schools webpages
The Rolladen-Schneider LS8 is a Standard and 18 metre class single-seat glider developed by Rolladen-Schneider and in series production since 1995. It is manufactured by DG Flugzeugbau. By the mid-to–late eighties the LS4 had lost its leading position in the Standard Class to new arrivals, in particular the excellent Discus from Schempp-Hirth; the LS7, in spite of its advanced design, did not recapture the lead and, with flagging sales, Rolladen-Schneider went back to the drawing board. Designer Wolf Lemke was skeptical of the usefulness of developing a new airfoil. There was no guarantee that the large effort and investment required would bring any palpable gains, as the LS7, ASW 24 and DG-600 had shown; the tools available at the time were not up to the task of reliably predicting the performance in everyday conditions of the newer laminar profiles emerging from the research labs. The 15 meter Class LS6 was however achieving good results flying with locked flaps in the non-FAI sanctioned Sports Class in the United States.
Following this lead, Rolladen-Schneider modified an LS6-c by removing the flap handle, resetting the wing at a higher angle of incidence and adding winglets. This experimental prototype outperformed state-of-the-art standard class sailplanes both in side-by-side flight tests and in contests including the German Championships at Neustadt-Glewe; the LS8 that emerged in 1994 had a few improvements over the prototype, the most significant being the redesigned ailerons and the lighter and aerodynamically cleaner wing made possible by deleting the flap system. LS8's scored second and fifth in the 1995 World Gliding Championships at Omarama, New Zealand, first and third in the 1997 World Gliding Championships at St Auban, six out of the first ten positions in the 1999 World Gliding Championships in Bayreuth, the first three places in the 2001 Women's World Gliding Championships in Lithuania and, more first in the 2005 Women's World Gliding Championships in Klix, Germany. In 2006 World Gliding Championships at Eskilstulna, Sweden, LS8 took the third places.
LS8 was the winner of 2002, 2004, 2005, 2007 European Gliding Championship. Many regard it as the best all-round standard class glider. Commercially the LS8 was successful, due to its competition potential and to the gentle and easy flight characteristics that make it suitable for club and leisure flying. To cater to the latter market, versions with longer wings and a ‘turbo’ or sustainer version were developed. A total of 491 examples of all subtypes had been manufactured by December 2005. Despite the commercial success of the LS8 the company producing it failed to prosper and after a acrimonious court battle the LS8 and other Rolladen-Schneider aircraft passed to DG where the LS8 with some alterations to the mainwheel, the Turbo version etc. is still in current series production with different model designations from the originals. The development of the sustainer "Turbo" version went through several iterations with the original prototype being manufactured by Rolladen Scheider for Peter Wright who designed a unique turbo design where the engine remained in the engine bay and drove the propeller via a belt.
Peter had many years experience working in composites and the Formula 1 industry. The prop which extended through a pneumatic mechanism was belt driven via a belt that ran inside the pylons which were Carbon Fibre aerofoil sections to minimise drag; the engine could be started using a starter motor before deploying the prop with the engine running, a small alternator recharged the battery and pneumatic reservoir. Air inlet and exhaust were accomplished through small pneumatic doors it the bottom of the fuselage again to allow engine running with the prop/pylons still in the bay and the main fuselage doors still closed; this arrangement whilst being admired by many was determined by the manufacturer to be too complex and expensive and a much more conventional Turbo design was selected for production by Rolladen Schneider. The LS design has since been modified by DG after their acquisition of LS with DG's in house DEI NT engine control system; the original Prototype LS8-t was converted back to a more or less standard LS8-b where it remains on the British BGA register now redesignated as the LS8-PW with the Competition number F1.
It is still unique in being the only LS8 on the CAA EASA Annex II list due to its status as a prototype due to the use of unidirectional carbon fibre on the wing skins, an attempt by Rolladen Schneider to improve the surface finish. Production turbos returned to using woven carbon again because of the increased production costs associated with using the more difficult to cut and handle unidirectional material; the LS8 is a flexible and conservative design with high development potential. Although designed to Standard Class specifications, it has lent itself to span extensions, etc. Aerodynamic configurations: winglets are default for all spans. Structure: wings, winglets and horizontal stabilizer are carbon/foam sandwiches; the longer span versions have a stronger main spar. The cockpit is a double fibreglass shell for increased crashworthiness. Control system: conventional, split elevator/horizontal stabiliser for longitudinal control and top surface Sch
Akaflieg Köln LS11
The LS11 or AFK1 is a prototype Two-Seater Class sailplane in development at Akaflieg Köln e. V.. The LS11 first flew on 5 November 2005. Akaflieg Köln initiated in 2000 the concept design for the AFK1. One of the design goals was to use as many standard LS components as possible in order to lower the development costs; this and the large contribution of Wolf Lemke, who performed the aerodynamic and structural calculations, led to Rolladen-Schneider bestowing the type designation LS11 upon the Akafliegers' project. The goal of the project is to design and build a capable school glider with top performance for cross-country training, record flying and competition; the LS11 gets its performance from an extended Rolladen-Schneider LS6 wing. After the Akaflieg Darmstadt D-41 demonstrated the feasibility of a high performance, multiplace glider based on the LS6 wing, the Köln Akafliegers felt they could profit from and improve upon that design; the wing structure resembles somewhat the Rolladen-Schneider LS9 structure.
The wings entirely made of Carbon fibre Reinforced Plastic, were manufactured at the Rolladen-Schneider factory in Egelsbach in mid-2001, while the span extensions were built in the moulds developed by the Darmstadt group for the D41. The LS11 prototype was featured as a work in progress at the 2003 and 2005 AERO Friedrichshafen exhibitions in Germany; the maiden flight was to be followed by a comprehensive flight test programme in 2006, to be carried out at Akaflieg Köln's home airfield, Dahlemer Binz in the Eifel region in Germany. The LS11 is slated for production by the Slovenian aircraft manufacturer AMS-Flight. If this comes to fruition, this will be the first prototype developed by a German academic association that reaches serial production; the LS11 is expected to have up to four interchangeable sets of wingtips for spans between 18 and 21 meters. The prototype has a 20-meter span in keeping with the new Two-Seater competition class. Water ballast bags inside the wings enable loadings up to 50 kg/m².
Two ballast tanks integrated into the rudder fin will keep the centre of gravity within its optimum range, compensating for ballast changes and heavier pilots. The empty weight was a serious design concern for reasons beyond mere ease of ground handling; as the scope for increasing the wing area was limited, since it originated on a single-seat design, the Akafliegers strove to achieve an empty mass as low as possible, in order to keep the wing loading of the shorter 18 meter span within reasonable limits. Some parts of the fuselage were adapted from existing production types, such as the tail boom of the LS4 and the empennage of the LS8. Considerable redesign was required, however; the span of the horizontal stabiliser was increased. The cockpit, manufactured from carbon and aramid reinforced plastic, was designed to accommodate pilots up to two meters tall. Available space is sumptuous for both pilots, exceeding that of all comparable production gliders; the front seat is similar to the LS4 cockpit, both seats have enough leg and elbow room to preclude the mutual interference too encountered in tandem sailplanes.
The maximum cockpit load is 230 kg. The large canopy is a single unit, it opens with an upward and rearward movement. The practicality of this concept for large glider canopies has been tested by Akaflieg Köln through the modification of three Scheibe SF-34 gliders; the hinge is a carbon reinforced element able to withstand wind speeds up to 75 km/h when open and was designed to sever the tubing and wiring looms from the instrument panels upon emergency release in flight. The airplane stands on a sprung, retractable main undercarriage with a six-inch hub, a nose wheel, sprung and retracts with the main wheel. A fixed tail wheel is provided; this undercarriage scheme simplifies ground handling. The main wheel is located near the glider's empty centre of gravity. All controls connect automatically upon assembly in the habitual LS way; the control system is built from standard LS parts. The wings are connected by two main pins inserted into the tongue-and-fork spar ends, as in the LS6 and subsequent LS types.
A low landing speed is essential for a trainer. Wolf Lemke and Siegfried Piontowski decided to depart from the typical LS system in which ailerons and flaps act as flaperons, using mixed schedule as featured in the Schleicher ASW 27. In landing configuration the flaps assume a deflection of about 75 degrees while the ailerons remain in a neutral position, enabling slower landing speeds with good control response. Multiblade airbrakes extend from the upper surfaces of the wings to give ample glidepath modulation. General characteristics Crew: 1 pilot Capacity: 1 passenger. V. Pictures of first flight Videos of the construction and maiden flight Akaflieg Köln YouTube channel
The Rolladen-Schneider LS1 is a Standard Class single seater glider, manufactured by Rolladen-Schneider from 1968 to 1977. The LS-1 Standard Class design was the first aircraft type arising from the partnership between Wolf Lemke and Walter Schneider, who had worked together as students on the ground breaking Akaflieg Darmstadt D-36. Here, in subsequent Lemke-Schneider designs, Wolf Lemke concentrated on the aerodynamics while Walter Schneider contributed to the structural and production issues; the LS1 made its debut at the 1968 German National Championships, taking first and second place with the designers themselves at the controls. The success of this design increased in the subsequent years until, in 1975, it was the most flown glider in the German Nationals; the LS1-c took first place in the 1970 World Championships at Texas. The manufacture of the LS1 was discontinued after the IGC introduced the new unrestricted 15 metre-class in the spring 1977, as the manufacturer needed all its resources to increase production of the LS3.
A total of 464 LS1 were built. It was succeeded by the LS2 and LS4; the designers desired to demonstrate that high performance and pleasant flight characteristics could coexist in a standard class sailplane built with the still unexplored GRP technology. The performance came from the high wing aspect ratio, the double tapered wing and the new FX 66-S-196 profile; this profile possesses a shallow but wide laminar bucket. The natural qualities of the profile combined with careful wing design yielded gentle low speed behaviour. Variants up to the LS1-d had an all-flying tail with oversensitive handling characteristics at high speeds. A conventional stabiliser and elevator were adopted for variants. Although fractionally less efficient, this is more pleasant to fly; the front of the original two-piece canopy was blended with the fuselage for improved aerodynamics. The materials used were glass fibre, Conticell foam, plywood for the spar webs and hardwood in reinforcements. Wood was phased out in the LS1-f version.
The FX 66-S-196 profile, with a thickness-to-chord ratio of 20%, made it possible to build a light and economical spar. This was important because in the late sixties glass fibre was the only affordable reinforcement material - carbon was still too expensive; the GRP fuselage shell was produced in female moulds, in an innovative method developed by Wolf Lemke. The LS1 V-1 prototype was the pattern or ‘plug’ for the serial production moulds; the undercarriage was fixed, as required by the standard class rules of the time. The wheel was had its own wheel housing, separate from the internal fuselage space; the wheel brake was coupled to the air brake system. The new one-piece canopy of the LS1-f required an innovative hinge with complex kinetics to deliver the forward opening movement. LS1-0 V-1 - prototype had an internal load bearing tubular steel scaffold; this structure was substituted by full GRP construction in production versions. LS1-0 - angle of incidence was increased and improvements to the control system.
LS1-a - trailing edge air brakes of the prototype were dropped in favour of conventional Schempp-Hirth air brakes LS1-b - LS1-c - LS1-d - was the first to have water ballast, following a class rule change. LS1-e - version was built by a Rolladen-Schneider employee under the direction of Wolf Lemke. Differs from the LS1-c only in the use of an LS2 type tailplane LS1-ef - tailplane of the LS1-f and the same fuselage as former versions LS1-f - introduced the one-piece canopy, conventional tailplane, redesigned rudder and structural changes that allowed more water ballast and higher flight mass, it has a reduced wing incidence relative to the fuselage, resulting in noticeably better high speed performance than the earlier LS1 variants. LS1-f - Data from General characteristics Crew: 1 Length: 6.75 m Wingspan: 15 m Height: 1.37 m Wing area: 9.75 m2 Aspect ratio: 23.1 Airfoil: modified Wortmann FX-66-S-196 sections Empty weight: 230 kg Max takeoff weight: 390 kg Water ballast: 90 l Performance Stall speed: 70 km/h Never exceed speed: 250 km/h in smooth and rough air170 km/h maneuvering speed 170 km/h on aero-tow 130 km/h on winch launchg limits: +5.3 -2.65 at 170 km/h.
The Rolladen-Schneider LS00390 is a 15 metre single-seat glider produced by Rolladen-Schneider from 1976 to 1983. The LS3 was developed as Rolladen-Schneider's first entry to the new 15 meter competition class created in 1974 by the International Gliding Commission of the Fédération Aéronautique Internationale. Building upon previous experience with the LS1 and LS2, chief designer Wolf Lemke developed a new fuselage with a larger cockpit and more generous horizontal and vertical stabilisers. Lemke elected a thick profile developed in 1967 by University of Stuttgart Professor Franz Xavier Wortmann, the FX 67-K-170, which offered the structural economy made possible by a tall spar - an important consideration as glass fibre was still the only affordable reinforcement material - as well as good performance for the time; this profile and its sister profile FX 67-K-150 are among the most prolific in the history of gliding, as they were employed in the Nimbus-2, Mini-Nimbus, DG-200 and DG-400, PIK-20 and PIK-30, Mosquito, Jantar and LAK-12 among other types.
Unusually for Rolladen-Schneider, the LS3 wings are single-tapered, entailing a slight aerodynamic loss. On the other hand, this geometry went along well with a straight axis for the full-span flaperons which gave the LS3 good handling and roll rate characteristics; the control system was rigged to reduce the available control stick throw with negative flap settings, therefore giving a measure of in-built protection against overstressing at high speeds. The flaperon drives are located at the wing roots, an elegant solution that required a large amount of lead for mass balancing the control surfaces to preclude any risk of flutter. Due to this the LS3 wings are heavy, about 85 kg each semi-span. In spite of its weight the LS3 is a nimble climber, it is less sensitive to rain or dirt than other types with the same profile. Its thicker wing takes its toll at higher speeds, where it could not keep up with the contemporary ASW 20, the best 15 metre glider of its generation. A variant with separate flaps and ailerons and a taller tail, the LS3a, was introduced in 1978.
This version did away with the flaperon mass balancing. A span extension to 17 metres was developed for this version. Although not successful due to speed and ballasting limitations, these extensions pioneered a trend that has become popular. Today most new standard and 15-meter class gliders offer tip extensions as an option; the LS3 was superseded in 1983 by the LS6. Its production run reached 429 exemplars of which two-thirds are of the -a version, it remains a popular glider in the second-hand market although it is found in club fleets due to the added complexity of flaps and undercarriage. Wings and horizontal stabiliser: spar and shell of glass fibre reinforced plastic/foam sandwich Elevator and fuselage: glass fibre reinforced plastic Automatic connections for flaperons, airbrakes and water ballast valves Water ballast system: unvented ballast bags in the wings LS3 - original production version LS3-a - improved version with separate flaps and ailerons and a taller tail LS3-17 - version with tip extensions for 17 metre span.
A glider or sailplane is a type of glider aircraft used in the leisure activity and sport of gliding. This unpowered aircraft uses occurring currents of rising air in the atmosphere to remain airborne. Gliders are aerodynamically streamlined and are capable of gaining altitude and remaining airborne, maintaining forward motion. Gliders benefit from producing the least drag for any given amount of lift, this is best achieved with long, thin wings, a faired narrow cockpit and a slender fuselage. Aircraft with these features are able to soar - climb efficiently in rising air produced by thermals or hills. In still air, gliders can glide long distances at high speed with a minimum loss of height in between. Gliders have 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 gliders are covered below. Gliders are launched by winch or aerotow, though other methods: auto tow and bungee, are used.
Some gliders do not soar and are engineless aircraft towed by another aircraft to a desired destination and cast off for landing. Military gliders are single-use only, are abandoned after landing, having served their purpose. Motor gliders are gliders with engines which can be used for extending a flight and in some cases, for take-off; some high-performance motor 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 the pilot can switch the engine on and off in flight without retracting their propellers. 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 added an engine.
After World War I gliders were first built for sporting purposes in Germany. 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 turned to gliders and were encouraged by the German government at flying sites suited to gliding flight like the Wasserkuppe; the sporting use of gliders 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 fly hundreds or thousands of kilometres in a day if the weather is suitable. Early gliders had the pilot sat on a small seat located just ahead of the wing; these were known as "primary gliders" and they were launched from the tops of hills, though they are capable of short hops across the ground while being towed behind a vehicle. To enable gliders to soar more than primary gliders, the designs minimized drag. Gliders now have smooth, narrow fuselages and long, narrow wings with a high aspect ratio and winglets.
The early gliders were made of wood with metal fastenings and control cables. 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 been minimized by more aerodynamic shapes and retractable undercarriages. Flaps are fitted to the trailing edges of the wings on some gliders to minimize the drag from the tailplane at all speeds. With each generation of materials and with 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, the glass-fiber Libelle of the 1960s increased that to 39:1, 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 the Space Shuttle with a glide ratio of 4.5:1. Due to the critical role that aerodynamic efficiency plays in the performance of a glider, gliders have aerodynamic features found in other aircraft; the wings of a modern racing glider have a specially designed low-drag laminar flow airfoil. After the wings' surfaces have been shaped by a mold to great accuracy, they are highly polished. Vertical winglets at the ends of the wings are computer-designed to decrease drag and improve handling performance.
Special aerodynamic seals are used at the ailerons 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 the wing; this flow control prevents the formation of laminar flow bubbles and ensures t
The Rolladen-Schneider LS5 was an Open Class single seat glider aircraft designed by Rolladen-Schneider. Only a single unit was built; the LS5 was announced in 1980 as Rolladen-Schneider’s entry into the exclusive Open Class. The economic viability of the design was compromised, with the arrival in 1981 of the Schempp-Hirth Nimbus-3 and the Alexander Schleicher ASW 22, both of which outclassed the predicted performance of the yet-to-fly LS5. Although the moulds had been completed, Rolladen-Schneider decided not to pursue further development. Klaus Mies from Kaiserslautern used these moulds to produce one glider of the type; this homebuilt prototype made its maiden flight in 1988, receiving the registration number D-7742. It is based at Marpingen in Germany. General characteristics Crew: One Length: 6.96 m Wingspan: 22.78 m Wing area: 13.9 m2 Aspect ratio: 37.3 Empty weight: ca. 370 kg Gross weight: 696 kg Performance Maximum glide ratio: ca. 55 Rate of sink: ca. 0.40 m/s Armament Geistmann D, Segelflugzeuge in Deutschland, Motorbuch Verlag LS-Flugzeugbau website sailplanedirectory.com