Akaflieg

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Akaflieg is short for Academic Aviation Group . Akafliegs are glider clubs that are based at a university and are primarily made up of university members.

Purpose of the association

Akaflieg's aim is, in addition to the development, design and construction of aircraft, especially gliders, research in aeronautics. The experimental investigations are mostly carried out at the annual summer meeting of Idaflieg (Association of German Academic Aviation Groups), the research results are presented at the annual winter meeting. The quality of the training that takes place in the Akafliegs in addition to the studies can be seen in the fact that almost all designers in the German glider industry belong to an Akaflieg.

As a member of an Akaflieg you have to work 150 to 300 hours a year to fly the club's aircraft. Maintenance and repair of the aircraft are carried out and towing operations are guaranteed during these working hours. The Akaflieg's construction projects and the maintenance of buildings and airfield grounds are also carried out. The costs for flight training and flying are significantly lower than in a "normal" glider club.

history

Otto Lilienthal established the basics of modern aircraft technology and aerodynamic flying in his book Der Vogelflug als Basis der Flugkunst , published in 1889, and from 1891 onwards through numerous gliding flights with his self-developed and built gliders. For this purpose, as a forerunner of today's wind tunnel investigations, he made measurements of lift and air resistance on bird wings as well as on differently shaped wing models in variation of the flow velocity and the angle of attack .

Since after the First World War, under the provisions of the Versailles Treaty, motorized sport aviation was no longer permitted in Germany, a new variant of motorless flying, known as gliding, emerged . The gliding movement was triggered primarily by Oskar Ursinus , who initiated the legendary Rhön competitions on the Wasserkuppe , which took place regularly from 1920. Here, among others, students from technical universities met who came to the Rhön with their self-developed and self-made flying machines for flight tests and flight competitions. A spirit of optimism, jokingly described as “Rhöngeist”, developed. Gliding established itself as a separate genre of sport aviation.

From this still informal movement, groups of pilots emerged at the universities with the aim of providing their student members with further scientific and practical training. They were financially supported by funds from the Black Reichswehr , which - similar to the popular sports schools for the infantry - promised to be able to fall back on suitably trained pilots more quickly in the event of rearmament. The first academic aviation groups were formed in Aachen , Darmstadt and Berlin-Charlottenburg (both in 1920), which others followed. Although many members were previously in the air force of the German army during the First World War , there was still no proximity to the spirit of militarism and nationalism such as the Academic Aviation Corporations or the student corporations . Even if the term “ old men ” or “old women and men” was later used for the former members after their studies, the Academic Aviation Groups had and still do not have corporate-like structures, but are characterized by rather casual manners.

During the Nazi era, some Akafliegs were initially able to evade Nazification under the patronage of the DVL ( German Research Institute for Aviation ) , a forerunner of today's DLR ( German Aerospace Center ) , and then incorporated shortly before the Second World War in the National Socialist German Student Union as flight technology specialist groups (FFG). The aircraft developments during this time were mostly related to military technology.

A few years after the war, the Akafliegs were able to re-establish themselves as independent groups, the renewed amalgamation of the aeronautical groups in the Association of German Academic Aviation Groups e. V. ( Idaflieg ) took place in 1951, in which ten groups are members (as of 2016).

Aviation Science Association Aachen

Akaflieg Aachen (actually: Aviation Science Association Aachen 1920 eV, short: FVA) was founded in 1920 at RWTH Aachen . The members are students of the RWTH Aachen and the FH Aachen .

The FVA-27 , a glider in duck configuration (planned from 1986), is currently under construction. In addition, research is being carried out on so-called "mini flaps" based on the Gurney Flap principle . These flaps on the trailing edge of the wing influence the direction of the outflowing air and thus the aerodynamic properties of the profile .

The FVA has had its own modern glider workshop just outside of Aachen since 2006. In order to honor the many hours worked by the group during construction, the workshop was given the project title FVA-28 .

Under the project name FVA-29 , a homecoming aid with an electric motor for the ASW 28 -18 with a specially designed propeller and drive train is currently being built. The first flight is planned for 2015.

Akaflieg Berlin

“Charlotte” as a signet

Akaflieg Berlin e. V. is a student association at the Technical University of Berlin, which deals with the development and construction of aircraft as well as aeronautical research. Founded in 1920, it is the oldest glider club in Berlin. During the time of the German division, the Akaflieg Berlin flew first in Waggum and from 1963 to 1993 on the glider airfield "Großes Moor" near Ehlershausen . Since the beginning of 1994, flight operations and flight training have been taking place on our own glider airfield in Kammermark in a flight and training community with the AFV Berlin (Akademische Fliegervereinigung Berlin) , which mainly consists of former Aka pilots, so-called "old ladies and gentlemen".

Akaflieg Berlin developments:

  • B 1 "Charlotte" : The first construction was a single-seat, tailless glider, construction of which began in 1921 and was completed a year later with the support of the Sablatnig works. The "Charlotte" was a braced full-wood shoulder decker with two runners and a wingspan of 15.2 meters. The construction was carried out by Hermann Winter and Edmund Pfister under the direction of August von Parseval . The aircraft was first flown by Hermann Winter at the 3rd Rhön competition in 1922, but it crashed a few seconds after take-off from about eight meters and broke. It was then rebuilt as "Charlotte II".
  • B 2 "Teufelchen" : The B 2, a single-seat glider from 1923, was designed by Kurt Tank and built with the help of LFG Stralsund . It was a cantilevered full-timber shoulder decker. In May 1923 she flew for the first time at the 1st coastal gliding competition in Rossitten . The following year, the pattern carried out an involuntary water landing in the follow-up competition and sank in the Baltic Sea.
  • B 3 "Charlotte II" : The successor to the B 1 was created in 1923 and, in contrast to this, had an improved control system, brake flaps and only one runner. The wingspan had been reduced to 14.2 meters. The constructors were again Hermann Winter and Joseph Kutin. The B 3 performed a few gliding flights in the 1923 Rhön competition, but collided with a tree. Winter, who flew the model, was unharmed.
  • B 4 : 1931, single-seat motorized aircraft, 20 HP, strutted high-wing aircraft, wooden fuselage, covered, fold-back wings
  • B 5 : 1937, single-seat performance glider, cantilevered middle-decker with gull wings, retractable landing gear, pendulum rudder, dive brakes, all wood
  • B 6 : 1938, single-seat performance glider, cantilevered mid-decker with Junkers double wing , retractable landing gear, pendulum rudder, dive brakes, tubular steel framework fuselage front section and tail girders in wooden shell construction
  • B 7 : 1939, two-seater performance glider, only project, was not implemented
  • B 8 : 1939, single-seat performance glider according to the Olympic tender, self-supporting shoulder wing, fixed gear, dive brakes, full wood, was built in two versions (version 2 = adjustable wing V-angle)
  • B9 with engines running, 1943
    B 9 : As early as1937,with the fs 17 of the Stuttgart Aviation Technical Group, investigations were carried out on the load limit of a lying pilot with high g- forces. In order to bring the results to a close, Akaflieg Berlin received the order for the B 9, which was later included in the RLM type list with the number 8-341. Only one example was built, which was designed for loads of up to 22  g . In order to enable the lying pilot to use the instruments, they were made visible via mirrors. The B 9 was completed in spring 1943 and began testing in August. The maximum load was not flown because the Me P2 controllable pitch propellers intended for this purpose were only available in 1944 after the test series had been completed. The B 9 was a cantilever low-wing aircraft with a composite construction and retractable landing gear. The drive consisted of two Hirth HM 500 engines, each 105 hp.
  • B 10 : 1944, two-seat twin-engine amphibious aircraft for travel, only projected
  • B 11 : 1963, single-seat, negative-swept, flying wing glider, was not completed
  • B 12
    B 12 : The B 12 is a two-seater in GRP construction with tandem arrangement of the seats. The aim of the project was the development of a fuselage optimized in terms of flow, especially in the higher speed range, using the wings of the Schempp-Hirth Janus . The B 12 has flaps and a retractable landing gear and is used for performance flight and competition use. The first flight of the B 12 took place in 1977 in Ehlershausen near Hanover. The shape of the fuselage was derived from an aerodynamically favorable rotational body developed at the Institute for Aircraft Construction, whereby the longitudinal axis was bent and a double-elliptical cross-section was chosen. As with many Akaflieg constructions of that time, the fuselage is strongly constricted in the area of ​​the wings. The performance
    measurement at the Idaflieg summer meeting in 1978 resulted in a best glide ratio of 41 as well as asomewhat flatter speed polarcompared to the Janus B ; the desired trunk optimization was thus successful.
  • B 13
    B 13 : The B 13 is a two-seater motor glider in CFRP construction with side-by-side arrangement of the seats. The span is 23.2 m and the performancemeasurementat the Idaflieg summer meeting resulted in a best glide ratio of 46.5. The wing profile is a modified flap HQ-41 profile. The seats next to each other offer both occupants a good view to the front and enable easy communication with one another. The hull was designed as a minimal hull in order to compensate for the disadvantages of the larger hull cross-section. The B 13 has good-natured flight characteristics with high maneuverability, even in slow flight. Developed in the eighties, it was completed in 1991 and in the same year had its successful maiden flight in Strausberg near Berlin. Problems with the integration of the internal combustion engine - a modified 24.5 kW Rotax 2-stroke engine - in particular the legally required firewall arrangement, ultimately prevented its use, so that the aircraft could only be operated as a pure glider until now. Therefore, in 2005, the new B 13-E project began to design the B 13 as a research aircraft and technology carrier for electric drives. Equipped with a brushless electric motor, the B 13-E was to accommodate various energy supply modules such as fuel cell and solar modules, whereby a 5-blade folding propeller, which was developed especially for the B 13 for the combustion engine variant, was to be used, which together with the engine is housed in the nose of the fuselage. The mechanism, developed and patented by Prof. Oehler, of a folding propeller that can be folded against the direction of flow enables extremely space-saving storage of the propeller in the tip of the fuselage. In 2006, the project was among the three winning projects in the Berblinger Prize of the city of Ulm . During the further mathematical interpretation of this electric drive concept, it turned out that due to the high weight of the B 13, reasonable rates of climb are practically impossible to achieve with the technologies available today, so that the B 13 should now only be used as a glider.
  • Akaflieg Berlin glider take-off winch
    Glider take-off winch : Because of the heavy weight of the new B 13 aircraft project, the group decided in 1984 to develop a more powerful sailplane take-off winch. The Daimler-Benz company donated a 320 hp 10-cylinder diesel engine including cable drums and axles for use as a towing engine. The development goal was - in addition to the higher performance, to be able to take off faster plastic gliders at their minimum speed even in calm conditions or with little tailwind. This requires a gear ratio design that enables a maximum cable retraction speed of around 110 km / h. Further design features are low rope bending under load due to large azimuth rollers and inclined rope inlet channels, automated operating processes through the use of a self-developed and built single-board computer to control the pneumatically driven operating actuators and a robust construction of the winch cell. Initially built on a 7.5 t chassis, the winch mass, which was steadily increasing during construction, made it necessary to purchase a larger chassis. In 1990 a three-axle all-wheel drive Tatra 148 was acquired from NVA stocks . Regular flight operations with the new winch began in 1994; since 2004 it has been operated with Dyneema plastic ropes.

Akaflieg Braunschweig

Akaflieg Braunschweig was founded on November 2nd, 1922. The clubhouse has been on the premises of the DLR Braunschweig since 1955 .

Akaflieg Braunschweig aircraft designs:

SB 5b, built in 1965 near Eichelsdörfer
  • SB 5 : The single-seat shoulder - wing glider in conventional wooden construction with a damped V-tail unit was the first construction of the Akaflieg Braunschweig after the Second World War . By using a laminar profile , excellent flight performance could be achieved without major construction costs or compromises in flight characteristics. The design of the aircraft corresponded to the rules of the FAI standard class. The first flight took place on June 3, 1959, on June 6, 1961 the aircraft was lost due to a break in a thundercloud; the pilot was able to save himself. The following version SB 5b had instead of the brake shield the SB 5a Schempp-Hirth -Bremsklappen and improved Einsteckhaube over the cockpit. After the span limitation in the new FAI club class waslifted, the span was increased to 16 m. Some successes have been achieved with this SB 5e. As a single piece was created in 1965, the SB 5c with fiberglass - balsa -Rumpfvorderteil with the design of the cockpit of the future SB 8 . The SB 5c was added to the list of monuments in 2012 in Lower Saxony as a movable technical cultural asset. Of the versions of the SB 5b ,around 50 copies were madeby amateur builders and by Eichelsdörfer GmbH in Bamberg. The SB 5e is a SB 5b with an enlarged span of 16 m
  • SB 6 : The SB 6 was the first Braunschweig aircraft to be builtusing a GRP construction with balsa wood as the support material. The improved contour accuracy enabled a better profile, which then also led to the very good performance we had hoped for. The first flight took place on February 2, 1961, at the Idaflieg summer meeting in 1964, the aircraft was destroyed through third-party negligence, while the group was still working on the strength of the new construction.
  • SB 7 : As a glider design for the standard class, the SB 7 should combine the good flight performance of the SB 6 with the flight characteristics of the SB 5. For its first flight in October 1962, the single-seater had a single-spar rectangular trapezoidal wing with an Eppler profile, Schempp-Hirth brake flaps and automatic rudder connections. The very low fuselage with retracted canopy and almost lying pilot position, retractable landing gear and pendulum T-tail unit should reduce the resistance. Since the Eppler profile tended to stall during slow flight, a Wortmann profile was applied to the upper side of the wing in 1969. In 1970 the wing span was increased by 2 m to 17 m, the airbrakes modified, a new horizontal stabilizer built, the fuselage height increased and the canopy divided. With the aircraft called SB 7B, the development goals had been achieved, but it had become quite difficult. Five SB 7s with different wing geometries and profiles were reproduced in Switzerland.
  • SB 8 : Based on the experience with the SB 7, the SB 8 was developed with the best possible flight characteristics and high performance in weak thermal conditions. Theaircraft designedfor the open class has a wingspan of 18 m and a flap, a fuselage with a T-tail that is strongly constricted behind the upright pilot and a curb weight of only 220 kg. The wings, fuselage and tail unit consisted of a full sandwich, used for the first time, with GRP on both sides of the balsa wood support material. Due to the excellent flight characteristics and performance, a second copy was created. The SB 8V2 had a significantly stiffer and heavier wing, who are no longer at higher speeds compared to the wings of SB 8 twist .
  • SB 9 : The wings of the SB 8 (V2) had been built with some strength reserves - since extreme lightweight construction like the SB 8 (V1) was not aimed for - which could now be used for a further improvement in performance by increasing the span. With attachable outer wings of initially 2 m each, the span was increased to 22 m. With this span expansion, the aircraft was given the type designation SB 9, the first flight of which took place on January 23, 1969. In order to increase the maximum permissible speed, the clip-on outer wings were later shortened by 0.5 m each, so that the SB 9 then had a wingspan of 21 m. During the flight tests of the SB 9, some flutter phenomena occurred, which could be captured in an impressive educational film. These flutter problems could, however, be eliminated by an aileron mass compensation. The consequence was that Akaflieg Braunschweig began developing an even larger prototype, the SB 10. Since the wings of the SB 9 had sufficient strength reserves, they were used for the SB 10, which in fact meant the end of the SB 9.
  • SB 10 : Akaflieg Braunschweig SB 10 was the largest and most powerful glider in the world at the time of its creation. Since the pilot's seat had to be far in front of the wings for reasons of flight mechanics (center of gravity), the aircraft was designed as a two-seater. In order to keep the wing deformation within manageable limits despite the enormous span, carbon fiber reinforced plastic (CFRP) was used for the first time in civil aircraft construction for the 8 m spanning middle section of the maximum five-part wing . The wing of the SB 9 served as the outer wing, which is why it has not been flown since 1973. The first flight of the SB 10 took place on July 22, 1972. With its full wingspan, the SB 10 is (usually) flown as a single-seater, as the maximum payload is only 140 kg. The three-part wing with a 26 m span is used for operation as a two-seater . In practical flight operations it was shown that the advantage of the division of labor in the two-seater more than outweighs the slightly better flight performance in the single-seater operation, which is why the SB 10 was mainly flown as a two-seater. In order to be able to increase the top speed, which was temporarily limited to 180 km / h, back to 200 km / h, a new, stiffer horizontal stabilizer was built for the SB 10 . The impressive data made the SB 10 a legend and helped it to achieve flight performance that was unrivaled for its time. The successes were not long in coming: on April 16, 1974, two members of Akaflieg flew from Braunschweig to Martizay / France and thus set a new German long-distance glider record for two-seaters. Originally a 750 km target flight world record to Orléans was planned (Orléans was also flown over), but the pilots took advantage of the good weather to continue the flight a bit. In the winter of 1979/1980 seven Aka pilots and the workshop manager shipped the SB 10 to Australia, where four two-seater world records were set in three months. Hans Werner Grosse, who initiated this trip to Australia, was on board on three of these flights. Furthermore, the flight of a 1000 km triangle succeeded there for the first time. During its useful life, the SB 10 was modified several times and limit values ​​were redefined, so that data such as payload, maximum permissible speed and the like changed several times. The SB 10 was flown by group members until the end of the 2003 season and regularly took part in the “Old Long Ears Cup” in Klix. Fortunately, in 2004 some “old men” from Akaflieg Braunschweig were found for the upcoming major overhaul, otherwise the aircraft would have been handed over to a museum. The group did not have the capacity for the major overhaul as construction of the SB 15 was due to begin. The work on the SB 10 was completed in 2012, so that the Akaflieg flagship has since returned to the Braunschweig sky and continues to delight its pilots. In 2015, the SB 10 was added to the list of monuments in Lower Saxony as a movable technical cultural asset. The gliding index is 118.
  • SB 11 : The Akaflieg Braunschweig SB 11 had its maiden flight on May 14, 1978. The SB 11 is a racing class aircraft with a wingspan of 15 meters and variable wing geometry. At that time, attempts were made to be able to optimally adapt the aircraft to the various flight conditions by changing the wings during flight. Akaflieg Stuttgart's fs 29 was designed for a similar purpose. While the Stuttgart-based company decided to change the wing area over a variable span, the Akaflieg Braunschweig decided to change the wing depth, which was achieved by means of gapless wing flaps (Fowler). This allows the SB 11 to change its wing area (and thus the wing loading ) by 25%. The advantages of the concept also quickly became apparent with the SB 11: Just two months after its maiden flight, the Braunschweig-based company gave its prototype to Helmut Reichmann, who won the racing class at the 16th World Gliding Championship. The prototype is based on the fuselage front part of the ASW 19 and the tail unit of the Janus B. The fuselage tube and the wings are an in-house development. The SB 11 was the first aircraft whose primary structure was built entirely from carbon fiber reinforced plastic (CFRP). Only the rudder is made of fiberglass to enable the installation of a radio antenna. The SB 11 has been in group ownership since its first flight and is still very popular. In winter 2001/2002 their surfaces were completely overhauled, work on the hull took place between winter 2007 and spring 2009. This means that the SB 11 is in almost perfect technical and optical condition, even more than thirty years after its maiden flight.
  • SB 12 : The SB 12 was created in just half a year. It was the first aircraft with blow-out turbulators to influence the boundary layer . Blow out turbulators consist of a series of tiny holes in the wing through which air is blown out. The SB 12 is based on the production aircraft Hornet C. The fuselage, tail unit and wings were manufactured by the students themselves (in the manufacturer's mold). The SB 12 was sold quite quickly and changed hands several times. She is now stationed in Braunschweig again.
Flying wing SB 13
  • SB 13 : The SB 13 is definitely the most sensational and ambitious project of the Braunschweiger. It is a "flying wing" glider, so it does without a conventional tail unit and tail unit carrier. Strictly speaking, it is not a “flying wing” in the narrower sense, as the cockpit is shaped like a conventional fuselage front section. The vertical stabilizer is housed in the enlarged winglets , while wing flaps similar to conventional flaps serve as the horizontal stabilizer. The resulting problems ( susceptibility to fluttering , pitching vibrations, lack of space, etc.) required innovative solutions and despite all efforts ensured that the SB 13 had to be changed during the construction phase. The efficiency of the concept was shown at various idaflieg summer meetings, but the very demanding flight characteristics throughout its life ensured that the SB 13 was only available to a limited group of pilots. Despite all the precautionary measures, rough landings were not uncommon, and landing gear repairs were the order of the day. In autumn 2000 there was another one, but at that time the group decided to take the aircraft out of flight operations for the time being. Since December 2006 the SB 13 has been in the aircraft yard of the Deutsches Museum in Oberschleißheim , where it is on display next to the Horten IV. The damage was repaired so that the aircraft is in principle airworthy. A total rescue system was specially developed and tested for the SB 13, including several attempts to drop a dummy fuselage from a helicopter. In the narrow cockpit there was no space for a back parachute, on the other hand the streamlined tail of the fuselage offered just enough storage space for a rescue system.
  • SB 14 : The SB 14 has a wingspan of 18 m. In contrast to the SB 13, the SB 14 aims to be more of an evolution than a revolution. The special thing about it is the new laminar profile optimized for high speeds, the aerodynamically optimized minimal hull and the consistent lightweight construction. These complex measures made it possible to achieve a glide ratio (approx. 50) for which the same group built the SB 10 with a 29 m span 30 years ago. The SB 14 has flaps and ispreparedfor the use of several rows of blow-out turbulators (one of which should be able to be switched off). In addition, various sensors were installed in the wings, the results of which are not only used for the development of further prototypes, but also by institutes of the TU Braunschweig and the DLR . The SB 14 had its maiden flight on January 17, 2003 and has been in flight testing since then. After completion of the spin flights in spring 2009, the broad-based testing will begin so that it will be open to other pilots.
  • SB 15 : The SB 15 is the current prototype of the Academic Fliegergruppe Braunschweig. The double-seater flap, which has been under construction since 2006, is to have a span of 20 m. The basic components are the fuselage of the fs 31 ( ASH 25 ), the wings of the SB 14, which have been extended by one meter, and the tail unit of the ASH 26 (SB 14). The resulting wing area is significantly smaller than that of comparable two-seaters, so that the particular challenge in this project is the extremely lightweight construction. Three student papers by members of the Akaflieg Braunschweig form the theoretical basis for the design. In a mass estimate, it was determined that the fuselage must be around 30% lighter than that of a mass-produced aircraft. This saving is to be achieved through new fiber materials and new construction methods, but also the detailed optimization of the fuselage internals.

Akaflieg Darmstadt

Akaflieg Darmstadt D-7 Margarete

The Academic Fliegergruppe Darmstadt e. V. at the Technical University of Darmstadt was founded in November 1920 by 70 members. Since it was founded, the association has developed over forty aircraft designs. The latest projects are a training two-seater (the D-43) and the pilot rescue system D-44 SOTEIRA. We flown, rehearse and train on the Lichtwiese , the Griesheim airfield and the Wasserkuppe . Currently, flights are being carried out at Heppenheim Airport (EDEP).

Akaflieg Darmstadt developments:

  • D-9 “Konsul” : single-seat, cantilevered glider that set a world record for distances in 1923
  • D-30 “Cirrus” : Experimental aircraft in a wood-metal composite construction

P13a (left on starter car) and DM1, model photo
  • D-33 / DM-1 : Akaflieg Darmstadt D-33 is a glider with a delta wing . This aircraft should serve the research of supersonic flight and was designed up to Mach 1.1, the development served as a preliminary project for the Lippisch P.13a . Wind tunnel investigations in America after the war showed that supersonic flight would have been possible with this type of aircraft. The D-33 project was continued after the destruction of the workshop in cooperation with Akaflieg Munich under the project name “DM1”, and the aircraft was brought to America after the end of the war.
  • D-34 (D-34a, b, c, d): The D-34 is the first post-war design from Akaflieg Darmstadt. It is a shoulder - wing monoplane with a one-piece wing . The fuselage has a T- tail unit . It was created in four built variants: D-34a (1955, designers W. Sarnes, HJ Merklein), D-34b (1957, designer G. Jacoby), D-34c (1958, designer M. Rade) and D-34d ( 1961, designers A. Puck, K. Weise and H. Wurtinger). The aircraft was primarily a test vehicle for new materials and construction methods. The D-34d was lost in a serious accident in Samedan on July 25, 1965. The D-34a had a plywood wing that was filled with foam . The ends were designed as vertebral lobes. A runner served as the chassis. For the D-34b, a new fuselage was built that had a retractable landing gear. The wing was built like the "a" version, but the wing area was reduced to 8.0 m² and the aspect ratio increased to 20. In contrast to its siblings, the D-34c was given a tubular steel fuselage. D-34d, in turn, took over the fuselage of the "b" variant. Your wing was made from a tie-bar-less GRP shell that contained a support structure made of paper honeycomb. The D-34c is today (2009) in the depot of the Wasserkuppe glider museum.
  • D-35 : The D-35 was the project of a tandem two-seater with a V-tail. The construction with GRP-supported paper honeycombs proved to be too difficult on a large scale, so that the project was abandoned in 1961 in favor of the D-36. (1959, designers A. Puck and H. Wurtinger).
  • D-36 (D-36 V1 & V2): The D-36 is a single-seat glider in plastic construction. The wing is designed as a middle deck and the tail unit as a T-tail unit. The D-36 was formative for the construction of high-performance sailplanes. In 1962, the planning of the D-36 began. The designers were: Gerhard Waibel ( fuselage and tail units), Wolf Lemke ( wing ), Klaus Weise (control in the wing, flaps and ailerons) and Heiko Frieß (airbrakes). Since torsional flutter on the horizontal stabilizer was detected during flight tests, Klaus Holighaus developed a new stabilizer. At the same time as the first V1 prototype, Walther Schneider built a second D-36 (V2). The first flight of the D-36 V1 was on March 28, 1964 in Gelnhausen . In the very first year she won the German Open Class Championship in Roth with Gerhard Waibel as a pilot . This was followed by a 2nd place at the World Championship in 1965 and a 3rd place at the German Championship in 1966. In 1967, the V1 was lost in the flight of clouds. Many of those involved in the construction of the D-36 later played important roles in the manufacture of gliders. The D-36 itself was the inspiration for their "series version", the ASW 12 . The fuselage of the D-36 is very slim, but in contrast to those of the competition at the time, it is constricted behind the cockpit and has thus become characteristic of modern glider fuselages. It has a retractable landing gear and a two-part canopy. It was produced in positive process over a core into two half shells and consists of a fiberglass - balsa - Sandwich . The wing is designed in a double trapezoidal shape. The profile is a Wortmann FX 62-K-131 at the root and a Wortmann FX 60-126. Originally it was also considered to use a profile developed by Wolf Lemke, but according to Gerhard Waibel this was not done for “image reasons”. In contrast to the fuselage, the two-part wing was produced using the negative process. A GRP balsa wood sandwich was also used for the grand piano. As a landing aid, the V1 had four-part, upwardly extending Schempp-Hirth flaps. The V2, like the ASW 12, had no airbrakes, only a braking parachute at the rear. With the D-36 V2 this could not be released. Slip down to the ground and only eject the parachute when the landing field has been safely reached. The brake flaps were later retrofitted by Akaflieg Saarbrücken. The V2 is now in the Wasserkuppe glider museum, but with a different hood than originally. After damage to the D-36, the cockpit and the seating position were changed. As a result, the aircraft lost its elegance.
  • D-37 : (D37 & D37b) Akaflieg Darmstadt D-37 is a single-seat glider in plastic construction. Originally it was planned and built as a motor glider that was not capable of self-launching . The wing is designed as a middle deck and the tail unit as a T-tail unit. After the success with the D-36, Akaflieg Darmstadt planned a motor glider with a retractable engine. The aim was to achieve high-performance properties, so that a compact, but also less powerful, rotary engine was used because of the limited weight and the small installation space available . The noise caused by the engine and the inability to self-start combined with starting difficulties in the air (the engine had no electric starter) led to the D-37 being dismantled as a pure glider. The late version as a glider is also known as the D-37b . The designers of the D-37 were Franz-Georg Sator and Wilhelm Dirks. The fuselage of the D-37 largely corresponds to that of the D-36. Only the area behind the cockpit had to be enlarged to make room for the engine. The fuselage is built in positive construction on a balsa wood core. The D-37 has a retractable landing gear. The wing was originally supposed to be based on a core made of two-component foam, but that failed. Instead, the wing consists of a GRP construction with fiberglass spars. The wing has a rigid profile and is relatively thick.
  • D-38 : Akaflieg Darmstadt D-38 is a single-seat glider in plastic construction. The wing is designed as a middle deck and the tail unit as a T-tail unit. In 1970 the design of a standard class aircraft began. The main goal of the development was to improve the flight characteristics. The D-38 became the prototype of the Glaser-Dirks DG-100 . The first flight was on December 19, 1972. The designer was Wilhelm Dirks. The D-38 is the second Akaflieg Darmstadt aircraft to precede a series variant. The fuselage of the D-38 is relatively long and clearly constricted behind the base of the wing. It has a retractable landing gear and the horizontal stabilizer is designed as a pendulum rudder with a Flettner trim. Like that of its sisters D-36 and D-37, this fuselage was also created in positive construction on a balsa wood core. The wing is a double trapezoidal wing with upward-opening Schempp-Hirth flaps and the option of holding around 50 l of water ballast . It was produced using the negative process.
  • D-39 : (D-39, D-39b & D-39 HKW) Akaflieg Darmstadt D-39 is a motor glider . The first flight was in 1979. The D-39 was designed as a touring motor glider with good gliding performance (15 m wingspan , 11 m² wing area and 370 kg armor mass) and was executed in a GRP-balsa composite construction. Originally, a folding propeller with a Wankel engine consisting of two coupled Sachs KM 914s , as used in the Hercules W 2000 motorcycle, was intended . However, synchronization problems of the two engines then led to the installation of a Limbach aircraft engine with 65 hp and a fixed screw. The further development of the D-39b was created due to the unsatisfactory gliding performance of the D-39. The wings of the D-39 were extended to 17.5 m span, swept forward because of the heavier engine and the landing gear modified. A controllable pitch propeller with a sail position finally gave the desired good performance in gliding ( glide ratio around 37). The D-39 HKW is a new design inspired and built by Heinrich Konrad Weinerth based on the D-39 fuselage shape with 20 m flap wing .
  • D-40 : Akaflieg Darmstadt D-40 is a single-seat glider of the 15 m class in CFRP aramid plastic construction. The wing is designed as a middle deck and the tail unit as a T-tail unit. A special feature of the D-40 is a wing flap that enlarges the area and works on the principle of a pocket knife. This flap is stored on the aileron attachment and extended or retracted at the attachment point.
  • D-41 : Akaflieg Darmstadt D-41 is a two-seater glider. A special feature of the D-41 is the arrangement of the pilot seats next to each other. This seating arrangement, which is otherwise rarely found in pure gliders, was chosen because, on the one hand, it enables more efficient training and, on the other hand, because both pilots can be accommodated in the laminar flow around the fuselage. Similar concepts were realized at the same time with the B13 and the Stemme S10 . In order to save costs and time, standard parts were used for the wing and the LS-6 wing was extended on the inside to a total span of 20 m.
  • D-42 : A single-seater self-launching solar motor glider with a wingspan of 18 m. After the design and some preparatory work, the project was discontinued because it was considered too costly. The engine should be retractable and power an adjustable propeller. The batteries should be charged by the solar cells during the flight.
  • D-43 : Side-by-side training two-seater based on the D-41 fuselage shape with an 18 m wing. The D-43 should enable improved communication between the student and teacher sitting next to each other. In 2009 an attempt to break the hull, which was endangered by the strong curvature of the hull and canopy frame, was successfully carried out. The first flight took place in 2014.
  • D-44 SOTEIRA : Pyrotechnic pilot rescue system that was to be installed in the D-43 for the first time. SOTEIRA will pull the pilot out of the aircraft with a rocket after the canopy has been released and open the parachute to enable a rescue from minimum height and with minimum airspeed, for example from the take-off or landing phase. Akaflieg Darmstadt's involvement ceased.
  • D-45 Helénē: A single-seater performance glider in the 15-meter racing class. The aim of the prototype should be a lightweight construction combined with a wide range of surface loads. Parts of the primary structure should also be made from prepregs . In order to be able to manufacture these without an autoclave, low-temperature prepregs with curing temperatures around 80 ° C are preferred. The project is in the basic design.

Akaflieg Dresden

Logo of Akaflieg Dresden

The Academic Fliegergruppe Dresden is now in its second generation, having been dissolved for the first time in 1933 after only eleven years of existence. In April 1998 the “new” Akaflieg was founded by students from the Technical University of Dresden, as the first Akaflieg in the new federal states. The home airfield has been in Schwarzheide since 2003 - together with the resident Aeroclub Schwarzheide e. V.

The students have been researching the current project since 2002, the DB 11. DB stands for "Dresdner Baumuster" and the 11 is the result of the ten aircraft that the first Akaflieg generation produced.

The basic idea behind the DB 11 is not that different from that of the prototypes at that time. The DB 11 is to serve the Akaflieg as a new training two-seater, since the last flight hours of the Bocian, which was previously used for training, are counted. The challenge in building DB 11 is that Akaflieg wants to build a high-performance, inexpensive (in terms of production), yet maintenance-friendly, robust, safe and, last but not least, ergonomic training aircraft. So that the effort for the young Akaflieg remains manageable, it was initially decided to "only" implement the sophisticated fuselage concept as a new development. The design of the Duo-Discus X as well as the know-how and friendly support of Schempp-Hirth Flugzeugbau GmbH can be used for the measuring wings and tail units .

For an optimal training two-seater, the aspects of ergonomics and safety come to the fore. In order to take these points into attack, Phillip Scheffel has taken as part of his thesis load assumptions for future construction and with the support of the IMA Dresden GmbH a proposal to build the main frames from carbon fiber - prepreg developed. Hans-Peter "Dabina" Ortwein started the design of a safety cockpit as part of his document "Structural mechanical design of the CFRP front fuselage of the DB 11 glider with regard to crash safety". Thomas Barth and Jörg Schreiber made the first studies of ergonomics. They essentially made a 3D construction of the cockpit interior. Later, with the help of the Institute for Materials Handling, Construction Machinery and Logistics and the Chair of Construction Technology / CAD, the model was spatially projected on a 1: 1 scale in a virtual reality environment. Further investigations into the exact cockpit design and the interior fittings are in progress.

Sebastian "Bolek" Radomsky took on the modification of the wings of the Duo Discus X. In the form of a receipt, he has dealt with the design of the surfaces as measuring blades so that they can later safely accommodate various measuring attachments without much (conversion) work. Not only work, but above all costs should also be saved in the construction of the fuselage, so the decision was made to use the “flying form” (MFF) construction method. This technology, which is not new in principle, enables the hull to be built without an independent negative mold set or positive core. However, the complex shape of the front fuselage poses a considerable challenge. In order to be able to reproduce the fuselage more easily later for possible tests, a shape should be removed from the prototype. The master model is currently being worked on in the workshop. However, there is still a lot of, initially constructive work to be done before the first flight.

Akaflieg Dresden developments:

  • DB 4 : First aircraft (motor glider) of Akaflieg Dresden, founded on April 14, 1924, whose members were partly recruited from the Dresden Aviation Technology Association (FVD). He had already developed the FVD two- decker (1921, colloquially known as "pork belly"), the monoplane " Doris " (1922) and the FVD "Falke" (1923). In 1927 the DB 4 was converted to the "Ebersbach" sailor. In November 1928, Wolfgang Pomnitz fatally crashed with the model. DB stands for "Dresdner Baumuster"
  • DB 7 : Glider from 1929 intended for training, which took part in the Xth Rhön competition.
  • DB 8 : High-performance sailor also developed for the X. Rhön. Due to the generous use of plywood for the planking, the DB 8 was quite heavy with an empty weight of 277 kg. On December 12, 1929, the aircraft with the pilot Erhard Muschick survived a flight at 115 km / h wind speed.
  • DB 9 : The DB 9 was the only two-seater that Akaflieg Dresden developed. Because of its high curb weight (320 kg) it was nicknamed the "armored cruiser". In 1930 the model received a prize for a one-hour storm flight and a seven-hour long-term flight during the Rhön competition. The plane crashed in June 1933.
  • DB 10 : The last aircraft of the Akaflieg Dresden before its dissolution on July 14, 1933 and at the same time its first model with a closed cabin was the high-performance glider DB 10. The type flew for the first time in autumn 1931 or spring 1932. Like all models of the Dresdner Akaflieg was value was placed on great stability (massive plywood planking), which is why the empty weight was 220 kg. Erhard Muschick took part in the 13th Rhön competition with the DB 10, but won no prizes, but later won the silver C for the first time in Saxony. After the association was dissolved, the model was sent to the Großrückerswalde gliding school. Its head Otto Braeutigam achieved in July 1935 during the XVI. Rhön and three other pilots set a world record of 504 kilometers.
  • DB 11 : The first Akaflieg Dresden aircraft that is currently under development after the association was re-established in 1998.

Aviation Technical Working Group Esslingen

The FTAG is a registered non-profit Flugsportverein. The members are almost exclusively graduates of the Esslingen University of Applied Sciences or the former Esslingen University of Applied Sciences (FHTE). These come from a wide variety of departments at Esslingen University of Applied Sciences, ranging from mechanical engineering, vehicle technology, computer science, utility / environmental technology, microsystem technology, electrical engineering, to social education and others.

Completed FTAG projects

  • FTAG - E1 : Duck plane with motorcycle engine. The basic idea behind the design was an aircraft that was easy to operate. The design and calculation were completed, the aircraft was not built due to tightening of the building regulations.
  • FTAG - E2 : Aerodynamically revised "Minimoa" . The lift coefficient has been increased by 45%, which improves maneuverability, but worsens stall behavior somewhat.
  • FTAG - E3 : two-seater high- performance glider with a high-speed profile , VHF transmission and reception system and a staggered seating arrangement. The E3 was the lightest aircraft in its class (90 kg lighter than the lightest competitor aircraft). The main fittings were glued for the first time in the history of glider construction and numerous tests resulted in a breaking load of 145,000 N. The E3 set a new world record of 8,000 m in the 1938 Rhön competition.
  • FTAG - E4 : Improved version of the E3 with a more powerful profile, narrower hull and a new type of bending-torsion construction in a detached wooden shell and glued-on metal skin. The construction, calculation and tests were largely completed when the work had to be stopped due to the outbreak of war.
  • FTAG - E5 : Novel, closed, streamlined transport trolley for gliders. Removable overall hood, low weight, small width and depth and a lower center of gravity made handling this transport trolley much easier. About 800 pieces were built after the license was granted.
  • FTAG - E6 : A further development of the E5 project and transport trolley for the E3.
  • FTAG - E7 : Gluing order from the Reich Aviation Ministry (RLM) together with the sister groups at the TH Darmstadt and the TH Stuttgart. Hundreds of attempts in metal, foam and plastic gluing for fuselage and wing shells were carried out as preparatory work for the series production of large aircraft, as they were not used again until 1952 in the USA and Great Britain.
  • FTAG - E8 : fully aerobatic light-weight motorized aircraft with 26 kW engine. Unrestrained double-decker with automatic controllable pitch propeller with a 3.80 m diameter and a speed of 800 rpm. Planned use as a field training aircraft and tow aircraft. The execution of the construction was not approved by the RLM.
  • FTAG - E9 : Motorized aircraft based on the E8 as a monoplane with large flaps and slats for extremely slow flight characteristics . The construction was canceled due to the effects of the war.
  • FTAG - E10 : High-wing aircraft similar to the Fieseler Storch with fixed slats and equipped with a VW engine.
  • FTAG - E11 : two-seater glider for the investigation of extreme forward sweep of the wings
  • FTAG - E12 : Licensed construction of a single-seater glider in composite construction of type K 8 . This aircraft was used in training until a few years ago.
  • FTAG - E13 :
    FTAG glider take-off winch
    The project started in the mid-1970s. Owning an 8-cylinder diesel engine including a rear axle motivated to start building a new winch. A double drum winch with large steel drums was designed to fit a 7.5 t truck. All winch units should be easily accessible. A comfortable, easily accessible driver's cab and easy and safe operation of the winch were requirements. In the years that followed, the structure steadily took shape: frame, rear axle, drums, hinged cover on the side, hinged cover on top, radiator cover at the front, azimuth rollers, cutting device, fuel tank, battery. A truck was procured and the body was assembled on the truck chassis. Pneumatics and electronics were finally installed, function tests carried out, the base coat was given the top coat, operating instructions were written, approval and testing applied for. In September 1988 the winch was transferred to Grabenstetten, a few weeks later the acceptance took place.
    • Engine: 8 cylinder
      CAD model of the E14
    • Daimler-Benz OM 402 diesel engine
    • Output: 188 kW at 2500 rpm
    • Torque: 830 Nm
    • Drum diameter: 1.25 m
    • Max. Drum speed: 450 / min
    • electro-pneumatic drum control
    • Carrier vehicle: Daimler-Benz type 709
    • Total weight: 6790 kg
  • FTAG - E14 : Design and construction of an extremely light 15 m standard class glider with high water ballast and low drag fuselage. To date, the design and construction of this prototype has included 27 diploma and study theses from a wide variety of FHTE disciplines.
  • FTAG - E15 : Design and construction of an electrically powered autonomous towing vehicle (Lepo) for winch cables. The vehicle should pick up winch ropes on request from the winch, bring them to the take-off point completely independently and then go back to a staging area. Various navigation algorithms and various controls are also to be tested. Another task of E15 is the transport of materials on the site from A to B. After no insurance could be found for the operation of an autonomous vehicle on a glider airfield, the project was spun off from FTAG. The participating students founded the new student group Brainrobots at Esslingen University.

Furthermore, various study projects in the fields of computer science and software technology are carried out.

Akaflieg Hanover

An exact date of founding of Akaflieg Hanover is not known. The developments of Akaflieg Hannover:

  • H 1 "Vampyr" :She appeared at the 1921 Rhön competition with the Vampyr , her first aircraft construction. The construction with a single-spar wing and plywood-clad torsion nose was trend-setting for further developments in aircraft construction and is still relevant in the age of glass, carbon and aramid fibers.
Vampire with wing twisting flying overhead, 1922
  • H 2 "Greif" : The further development of the Vampyr for the Rhön competition of 1922 with an aerodynamically improved, rounded fuselage with a smaller cross-section. The model had poorer flight characteristics than its predecessor because of the bulge for the pilot's head in the center section of the wing, which caused a stall in this area of ​​the wing.
Greif in the Rhön, August 1922
  • H 5 "Spatz" : Small glider from 1923 with a wingspan of 7.5 meters with wing control. The pattern was already destroyed during testing.
  • H 6 “Pelikan” : A model constructed in 1924 with a tensioned, extremely thin wing. The wing broke at the first start at the 5th Rhön competition and also destroyed the vertical stabilizer. The plane crashed, the pilot Gustav Koch got away with the horror.
  • H 7 : A small glider from 1923 with a 5.2 meter wingspan. It was flown by the students of Akaflieg Hanover for training at the Wasserkuppe.
  • H 8 "Phönix" : This glider was built in 1925 and was flown in Rossitten as a series of measurements test bench for cockpit instruments .
  • AFH 4 : The aircraft was built in 1938 as the first construction since Akaflieg was incorporated into the DVL . It was characterized by great maneuverability and a high cruising speed. During the 19th Rhön competition, Wolfgang Schultz crashed fatally with the AFH 4. It was then rebuilt and tested, but some time later Herbert Vollmer steered it into a storm front and crashed a second time, this time for good. The pilot was able to save himself with the parachute.
  • AFH 10 : The AFH 10 was the successor to the AFH 4 from 1939 with an enlarged wing area and airbrakes and flew at the Idaflieg summer meeting in Prien in 1941 . It was captured by British soldiers in 1945 and taken to Farnborough, where it was scrapped in the early 1950s.
  • AFH 11 : The construction of the AFH 11 with a tubular steel hull and a planned span of 18 meters began in 1941, but was no longer completed because of the war.

Akaflieg Karlsruhe

The Akademische Fliegergruppe Karlsruhe e. V. was founded in 1928, banned in 1933 and re-established in 1951 after the allied flight ban was lifted.

Logo of Akaflieg Karlsruhe

The developments of Akaflieg Karlsruhe:

Akaflieg Munich

Akaflieg Munich was founded in 1924. Hanns Weidinger was an honorary member . It currently has around 40 active members who, among other things, design and build the high-performance glider Mü 31 at the Technical University of Munich in Garching.

Akaflieg Munich developments:

  • Mü 26 : “Cigar body” with a small cross-section made of GRP with a pendulum V-tail , wooden wing with an Eppler laminar profile designed for slow flight. Glide ratio 40. First flight July 1971, 1984–1997 reconstruction after an accident
  • Mü 27 : Similar to other Akafliegs, the practicability of changeable wing geometries was also tested in Munich in the 1970s. The concept of the Wortmann flap was testedon the Mü 27, whichallows an increase in the wing depth with high aerodynamic quality. The complex mechanics required a high level of development effort and ultimately the Mü 27 became the world's heaviest glider. The aircraft has been able to demonstrate its potential since its first flight in 1979, especially on cross-country flights, but since it is very unwieldy, it has only been flown very rarely and has been in the halls of the Deutsches Museum in Oberschleißheim since 2008.
  • Mü 28 : With its maiden flight in 1983, it wasthe only glider designed for aerobaticsalongside the outdated Lo 100 and SZD 20 “Kobuz”types. Thanks to the symmetrical profile and the automatic flap system, which was also developed by Akaflieg Munich, the aircraft has the same performance in all flight conditions, which leads to a harmonious flight pattern. During the flight tests, speeds of up to the indicated 400 km / h (480 km / h TAS ) were flown, making the Mü 28 currently the fastest glider in the world. The construction has proven itself in everyday operation and is regularly flown in competitions, and world championships are already on the list.
  • Akaflieg Mü 30 "SCHLACRO"
    Mü 30 “Schlacro” : the concept of the two-seat motorized aircraft became the name: SCHLACRO - tow and acro aircraft. The first flight took place in 2000. The idea behind the design of the Mü 30 is that aerobatic aircraft have an enormous excess of power that can be used not only for aerobatics, but also for (efficient) towing of gliders. Aerobatic machines achieve very high rates of climb, which make towing fast and, under certain circumstances, inexpensive.
  • Akaflieg Mü 31
    Mü 31 : The aim of the development of the Mü 31 is the implementation and testing of an optimized fuselage-wing transition on a person-carrying glider. The areas of assembling different assemblies are currently still one of the most difficult problems in aerodynamics to deal with, which is why such a project is suitable for closing the circle between computer simulation, wind tunnel model and reality and thus doing important evaluation work. On the other hand, this design should of course also increase the performance of the currently very exhausted sailplane configurations. The aircraft is designed as a shoulder-wing wing, which means that the intersection of the wing with the fuselage is very small and more lift-generating area is available. In addition, the wing is twisted in the vicinity of the fuselage in order to compensate for the loss of lift due to the fuselage, whichleadsto less induced drag due to the improved lift distribution of the overall
    configuration . The profiling has also been changed here. The fuselage was deformed in the sense of an optimal pressure distribution in the area of ​​the wing and merges into a very slim tail girder after the end edge of the wing, in order to reduce the surface area washed around as much as possible. The Mü 31 will thus be the first glider with a “real” fuselage-wing transition. The first steps in the development were already taken in the late 1990s, when the wind tunnel measurement of three models proved the presumed superiority of a configuration comparable to the Mü 31 compared to a conventional one. In order to reduce the construction and construction costs, parts of the geometry of the Mü 31 were adopted from the ASW 27 series aircraft. In the following years, after extensive CFD analysis, an optimized geometry was found, which was measured in the laminar wind tunnel of the TU Delft in 2005 and corresponds to the expectations. At the same time, the construction wascarried outin CATIA and a strength calculation was made. Due to the aerodynamically optimized area of ​​the fuselage-wing intersection, new concepts had to be found for both the control system and the structural connection between the two components. From 2005 to 2007 a set of molds was made for production, from which both the components for fracture tests and the components for the final Mü 31 were molded. The Mü 31 completed its first flight on September 15, 2017 at the Königsdorf gliding center and has been in flight testing and flight performance measurement since then.

Akaflieg Stuttgart

The Academic Fliegergruppe Stuttgart e. V. (Akaflieg Stuttgart for short) was founded in 1926 by members of the "Flugtechnischen Verein Stuttgart e. V ”was founded with the aim of designing and building aircraft itself.

Akaflieg Stuttgart projects:

  • F1 Fledermaus : The first self-constructed glider of Akaflieg Stuttgart was optimized in the wind tunnel and had no rudder, but end plates on the wings for control. At 21 kilograms, the bat's fuselage was very light, and the airplane won several prizes in the 1933 Rhön competition. Built in 1932, first flight in July 1933, construction: wood
  • fs 16 Wippsterz : Due to the urgent need for aircraft at Akaflieg, far-reaching innovations were not made in the fs 16 and a conventionally designed high-wing aircraft was built. Innovations were the aileron joints attached directly to the spar, and the ailerons themselves were made of duralumin. Built in 1936, first flight in February 1937, best glide ratio: 27, construction: wood, duralumin
  • fs 17 : Test glider for a lying pilot arrangement in order to cope with larger load multiples. That is why the hull boat was designed to be particularly stable to protect the pilot during somewhat harder landings. The wing spar should also absorb torsional forces in the area - an absolute novelty. Air brakes at the end of the fuselage were also tested. Built in 1937, first flight March 21, 1938, construction: wood. The test series was continued with the B9 .
  • fs 18 : With the fs 18, a high-performance glider for competitions was created. It was the first glider to have a retractable landing gear. Flaps were used on the high-wing aircraft to enable tight circles in the thermal. Other special features were dive brakes and the pendulum design of elevator and rudder. The pilot Ernst Scheible was killed in an accident in December 1938 and the aircraft was destroyed. Built in 1938, first flight July 21, 1938, best glide: 26.9
  • fs 18b to fs 22 : The projects fs 18b to fs 22 could never be realized due to the Second World War.
  • fs 23 Hidalgo : The fs 23 was designed for the 13 m mini class discussed at the time. In the construction phase 1953–1966, completely new materials and construction methods such as sandwich construction methods with a balsa wood core and GRP top layer were used. To do this, lengthy tests on the behavior of these materials first had to be carried out. With a setup mass of just 102 kg and a negative sweep of 5 degrees, the Hidalgo had excellent flight characteristics. Instead of brake flaps, a reefable brake parachute was used at the stern. A first accident in 1967, caused by tail flutter, made it necessary to strengthen the V-tail, the second break in 1971 cost the pilot Heinz Jahn his life.
  • fs 24 Phoenix : When the fs 24 took off for the first time on November 27, 1957, it was the first glider ever made entirely of balsa wood and fiberglass-reinforced polyester resin. The development of laminar profiles made an improved surface quality necessary, which could no longer be achieved with conventional timber construction. With a span of 16 meters, the Phoenix had an excellent glide ratio of 37. The fs 24 isexhibitedin the Deutsches Museum today.
  • fs 25
    fs 25 Cuervo : Since the greatest optimization potential for gliders was seen in the fuselage, the wing shapes of the Hidalgo were "recycled" for the fs 25. The optimization resulted in a strongly constricted hull boat made of balsa-GRP sandwich with a tubular steel frame, which takes all the loads from the wheel, coupling and wing. The tail unit was connected through a thin aluminum tube. After a construction period of only two years, the Cuervo was able to take off for the first time on January 30, 1968 and impress with its excellent climbing performance.
  • fs 26 Moseppl : The first self-made motor glider from Akaflieg Stuttgart was designed without a tail, with a pressure screw drive and a separate elevator. Due to a lack of space in the fuselage, the landing gear was designed hydraulically. The front part of the fuselage could be taken over from the production aircraft "Phoebus" and the engine was housed in the rear. After two years of construction, the Moseppl took off for the first time on September 25, 1979. Today the fs 26 can be viewed in the Manfred Pflumm International Aviation Museum in Villingen-Schwenningen.
  • fs 27 : The fs 27 was basically an fs 25 with a sheathed flow propeller in the fuselage connection. However, the project never got beyond the planning phase.
  • fs 28 Avispa : The main goals of the fs 28 were to adopt aerodynamically high-quality forms from glider construction and to reduce noise. That is why the powered airplane was designed with a pressure screw and overhead exhaust pipes. In addition, the V-tail and a retractable landing gear made of CFRP multilayer laminate ensured excellent aerodynamic properties. The project, funded by the Fraunhofer-Gesellschaft and the Ministry of Economics of the State of Baden-Württemberg, was built within two years and had its first flight on December 20, 1972. At a cruising speed of 250 km / h, a range of more than 1000 km is possible.
  • fs 29 TF : The attempt to optimize a glider wing for different speeds led to two approaches: changing the surface depth versus changing the wingspan. Akaflieg opted for the latter. Using a hand pump, the pilot can continuously telescope the wingspan from 13.3 m to 19 m in flight. The outer wings slide over the inner wings like gloves. Since the airbrakes can only be used when the wings are fully extended, the fs 29 had a braking parachute. On June 15, 1975, the prototype, which was quite heavy with an empty weight of 357 kg, was flown for the first time. The fs 29 is the only glider with wings that can be telescoped in flight. It is exhibited in the aircraft yard of the Deutsches Museum near Munich.
  • fs 30 : The airfield building, the second home of the Akaflieger on the airfield in Bartholomä, is the only non-flying project of Akaflieg Stuttgart. In honor of those active at the time who had put a lot of work into the house, the house was given an fs designation.
  • fs 31 Ferdinand Porsche : Since Akaflieg naturally also accepts students who are not experienced in gliding, a training two-seater was required. The surfaces of the Twin Astir were taken over by Grob and the hull designed itself. The focus here was on the aerodynamics and the cockpit in full-shell design; the use of the hybrid fiber carbon-aramid also enabled a light structure. Even on its first flight on December 30, 1981, the fs 31 showed harmless flight behavior and excellent performance, the robust landing gear makes it the ideal training aircraft. The shape of the fuselage constructed at that time has now been used for the ASH 25 and projects of other Akafliegs.
  • fs 32 Águila : Due to the split Fowler flaps, this single-seater can circle extremely slowly in the center of updrafts and thus climb as best as possible. In high-speed flight, the fs 32 performs like a modern racing-class aircraft. In order to keep the mechanics inside the wings (approx. 3000 parts each) smoothly at all times, the wings had to be designed to be particularly rigid. The use of the Ventus B hull from Schempp-Hirth enabled completion within six years. The first flight took place on February 18, 1992.
  • fs 33 Gavilán : With the fs 33 Gavilán, a high-performance two-seater, the Akaflieg mainly wanted to be ready for action quickly. The shape of the fs 31's fuselage was reused, the surface of the fs 32 was stretched to 20 m, the Nimbus tail unit from Schempp-Hirth was used and another two-seater was obtained within six years. The first flight was on June 27, 1998.
  • fs 34 Albatros : The Albatros was supposed to be a 15 m racing class aircraft with variable wing geometry, but the project was abandoned in 2002 in favor of the fs 35.
  • fs 35 Harpy : Tow motor glider with which a more powerful engine was used than was previously the norm in motor gliders. Consistent lightweight construction is intended to compensate for the additional weight of the engine in order to meet the criteria for the approval of motor gliders. The first flight was on August 13, 2019.

Akaflieg Wilhelmshaven

Akaflieg Wilhelmshaven was founded on May 19, 2009. There are three main areas: gliding, powered flight and flight simulation. Motorized flight takes place at the Mariensiel (Sande) airfield. Gliding is operated on places in the region. Akaflieg Wilhelmshaven has been a corresponding member of Idaflieg since January 2011.

Projects

A first project (cockpit) in the field of flight simulation has already been successfully completed. We are currently working on a flight simulator with a hydraulic platform (including the airframe). Projects in the field of motor and glider flight are currently being planned.

Akaflieg groups without membership in Idaflieg

Akaflieg DB

The Akaflieg DB (Academic Fliegerabteilung German fraternity e. V.) in 1930 by the German fraternity founded and consists almost exclusively of members of the Darmstadt fraternity Germania . An air camp built in 1935 on the Hohen Dörnberg is used together with the Kassel-Zierenberg aviation association.

Akaflieg Frankfurt

The Akaflieg Frankfurt in 1929 at the University of Frankfurt founded. The Akaflieg Frankfurt develops and builds airplanes, as the University of Frankfurt does not have Engineering / Aviation Institute has. It is not a member of Idaflieg , but pursues a number of gliding-related research projects in the areas of flight meteorology , safety, accident prevention and new technologies. The main focus is on the research of atmospheric gravity waves through annual expeditions to the Pyrenees (Akaflieg Frankfurt Wave Research Camp) and thermal research through data analysis (e.g. more precise modeling of thermals using swarm intelligence or LIFT: the logger-based intelligent Frankfurt thermal map). The Akaflieg Frankfurt participating in the Night of Science on the natural science campus Riedberg part. The Frankfurt Akaflieger fly on the glider airfield "Der Ring" in Schwalmstadt - Ziegenhain on the edge of the Knüllgebirge .

Akaflieg Freiburg

The Academic Fliegergruppe Freiburg i. Br. E. V. ("Akaflieg Freiburg") was founded in the 1920s. It is based at Freiburg Airport and is characterized by the colorful mix of members who come from all age groups and professions. Aviation activities include glider and powered flight.

Akaflieg Hamburg

The Akaflieg Hamburg has existed since 1984 and operates since 1994, a private Segelfluggelände in close Boizenburg located New Gülze . Its main goal is to offer students an inexpensive way to get started in aviation.

Akaflieg Kaiserslautern

Akaflieg was founded on February 23, 2010 in Kaiserslautern. Your home airfield is the Eßweiler airfield on the premises of the Eßweiler air sports club . It is currently under construction. Own projects are not known.

Akaflieg Kiel

Christening of an Akaflieg Kiel aircraft at Kiel-Holtenau airfield , 1964

Akaflieg was founded again in 1931 and 1957 at the Christian-Albrechts-Universität zu Kiel as a student university group and actively operates gliders at the Kiel-Holtenau airfield .

Akaflieg Cologne

The Akaflieg Cologne is the student Fliegergruppe the University and the Sports University in Cologne . However, there are also non-academics among its members. The club flies at the Dahlemer Binz airfield in the Eifel.

Akaflieg Cologne became known through some modifications (e.g. retractable landing gear for SF-34 , folding hood that opens to the rear), through the development of winglets for the LS4 and through the investigation of the side thread . At the end of 2005, the two-seater LS 11-AFK 1 was the first in-house design to make its maiden flight. The 20 m class glider was created using the extended front fuselage section of the LS4, an enlarged LS8 vertical stabilizer and the LS6- based wings of the D-41.

Akaflieg Merseburg

Akaflieg Merseburg was founded on November 26th, 2008 as a university association Academic Aviation Group Merseburg to promote air sports, science, research and teaching in the field of aviation, as well as the scientific and aviation youngsters. The planes: Weller UW 9 Sprint, Comco Ikarus C22, C42 and M 2 belong to the Akaflieg aircraft squadron.

Akaflieg Saarbrücken

A group of people interested in Saarland received an airplane as a gift from the French High Commissioner Gilbert Grandval in 1953 . From this group, the Akaflieg Saarbrücken emerged on April 14, 1958, which became known for the construction of an LS5 and the three-time world champion in gliding, Helmut Reichmann . Located at Marpingen airfield and a workshop on the campus of Saarland University .

Akaflieg Tübingen

The Academic Aviation Group at the University of Tübingen e. V. ("Akaflieg Tübingen"), was founded in the 1950s by students who were enthusiastic about gliding and was affiliated to the sports institute of the University of Tübingen until the 1960s . Akaflieg Tübingen has been an independent association since 1962 and is registered in the Stuttgart register of associations . Together with three other aviation clubs from the Neckar-Alb region , Akaflieg Tübingen operates gliding and motor gliding on the Übersberg glider airfield. Although Akaflieg Tübingen regularly offers a beginner's glider course via university sports at the University of Tübingen, you don't have to be a student or academic to become a member.

Flight technical working group at the FH Aachen

The Aviation Technical Working Group at the FH Aachen eV is a glider club based at the FH Aachen that actively operates gliders at the NATO airfield in Geilenkirchen . It was founded in September 1961. Among other things, the Röger hook was developed at FAG Aachen . Although the association consists mostly of students, non-academics can also be members. The association offers glider training through the DAeC . Due to the size of the NATO airfield Geilenkirchen, between 500 and 650 meters can be reached in winch launch .

Former Aka flying groups

Former Akafliegs, which were not re-established after 1945, existed u. a. in Chemnitz, Danzig (1923–1945, FFG since 1939) and Stettin. The Flugtechnische Arbeitsgemeinschaft (FAG) Chemnitz, the FFG Danzig and Göttingen developed the measuring crow together with the FFG Munich .

Aka flying groups in other countries

Akaflieg groups abroad cannot be members of Idaflieg as such. Academic groups exist at universities in Denmark , Finland , the Netherlands and Poland . They maintain more or less close connections to Idaflieg or individual German Akafliegs.

Delftse Student Aeroclub (Netherlands)

A formerly scientifically very active group of pilots existed at the Technical University of Delft . The research work was carried out around 1980 mainly by the two-time glider world champion Baer Selen. At that time there were also close contacts with Idaflieg.

Akaflieg Graz (Austria)

The Akaflieg Graz in 1921 at the Technical University of Graz founded and is the oldest gliding club in Austria . Akaflieg Graz built and developed its own aircraft until 1945 . After that, aircraft were only built occasionally, and today Akaflieg Graz is an Akaflieg with its own flight school , which is mainly geared towards flying. At the moment, Akaflieg Graz is neither researching nor building. There are no contacts with Idaflieg.

In 1992 there was a 20 m² workshop in the house at 32 Schörgelgasse in Graz. The association had two sections: gliding and model aircraft. The workshop was temporarily closed for a comprehensive renovation of the building. Today (2018) the club premises, the model workshop and the aircraft workshop are again in Schörgelgasse 32, whereby the size and equipment of the workshops corresponds to today's standards. Akaflieg Graz currently has 3 sections: gliding, powered flight and model flight. We also run a flight school for glider and powered flight.

Akaflieg Leoben (Austria)

The Academic Aviation Group Montanuniversität Leoben was founded in 1952. Akaflieg Leoben is a glider-oriented association. There is currently neither research nor construction going on there.

Koło Naukowe Lotników (Poland)

The Koło Naukowe Lotników (KNL) is the Akaflieg at the Politechnika in Warsaw . The association was founded in 1962 and is scientifically active. It stands in the tradition of predecessor associations that designed and built aircraft in Poland between 1923 and 1949 . There were contacts with Idaflieg.

Polyteknikkojen ilmailukerho (Finland)

Polyteknikkojen ilmailukerho ry abbreviated PIK is a student association at the Aalto University in Finland Espoo . He has been in the aerospace research field since 1938 and has earned an excellent reputation for excellent designs. Several types of aircraft were produced in large and small series. PIK maintained contacts with Idaflieg.

Polyteknisk Flyve Group (Denmark)

The Polyteknisk Flyve group (PFG) is the Akaflieg at the Technical University of Denmark (DTU) in Lyngby . The association is scientifically active. There were contacts with Idaflieg. One of the group's own designs is the Polyt V , a wooden tow plane that was designed purely for aircraft towing . The prototype first flew in 1970.

Web links

Commons : Akaflieg  - Collection of images, videos and audio files

Individual evidence

  1. Arnd Krüger & Frank v. Lojewski: Selected aspects of military sports in Lower Saxony in the Weimar period, in: Hans Langenfeld , Stefan Nielsen (Ed.): Contributions to the history of sports in Lower Saxony. Part 2: Weimar Republic. (⇐ Series of publications by the Lower Saxony Institute for Sport History , Vol. 12) Hoya: NISH 1998, pp. 124–148
  2. a b Frank-Dieter Lemke, Rolf Jacob: The Academic Fliegergruppen in Germany until 1945. Part 1 in: Flieger Revue Extra. No. 29, Möller, Berlin, March 2010, ISSN  0941-889X , pp. 57-59.
  3. ^ Frank: Berlin B 9 (8-341) . airmodel Frank-Modellbau, Albstadt.
  4. The SB 5c has been recognized as a "movable technical cultural asset" since 2012 (accessed on June 22, 2019)
  5. ^ Georg Brütting : The most famous gliders . Motorbuch Verlag, Stuttgart 2003, ISBN 3-613-02296-6 , p. 128.
  6. Academic Fliegergruppe Braunschweig (Ed.): SB 5 - SB 15. Glider Braunschweig. 2nd Edition. Appelhans-Verlag, Braunschweig 2013, ISBN 978-3-941737-73-0 , pp. 61-65.
  7. Academic Fliegergruppe Braunschweig (Ed.): SB 5 - SB 15. Glider Braunschweig. 2nd Edition. Appelhans-Verlag, Braunschweig 2013, ISBN 978-3-941737-73-0 , pp. 69-73.
  8. Academic Fliegergruppe Braunschweig (Ed.): SB 5 - SB 15. Glider Braunschweig. 2nd Edition. Appelhans-Verlag, Braunschweig 2013, ISBN 978-3-941737-73-0 , p. 80.
  9. ^ Georg Brütting: The most famous gliders . Motorbuch Verlag, Stuttgart 2003, ISBN 3-613-02296-6 , pp. 126-127.
  10. Fred Thomas: Fundamentals of Sailplane Design. College Park Press, College Park 1999, ISBN 978-0-9669553-0-9 , p. 179.
  11. SB 10 is one of 21 flying monuments (accessed on June 22, 2019)
  12. Akaflieg Braunschweig: The current project SB 15. Accessed on January 28, 2010 .
  13. ^ Page of Akaflieg Darmstadt , accessed on April 23, 2010
  14. a b German glider museum with model flight, Wasserkuppe . Segelflugmuseum.de. April 27, 2007. Retrieved September 11, 2010.
  15. Gerhard Marzinzik: The Darmstadt D-43 flying. In: aerokurier. Retrieved December 22, 2014 .
  16. Akaflieg Darmstadt: D-44 “Soteira”
  17. D-45 . In: Akaflieg Darmstadt . 2017 ( tu-darmstadt.de [accessed September 27, 2017]).
  18. E15 has arrived in the workshop. Current status E15. Aviation Technical Working Group at Esslingen University of Applied Sciences, October 17, 2012, accessed on January 3, 2017 .
  19. ^ Frank-Dieter Lemke, Rolf Jacob: The academic flying groups in Germany until 1945. Part 2 in: Flieger Revue Extra. No. 32, 2011, pp. 60-66.
  20. AK-9: DG-1000J turbine. Akaflieg Karlsruhe, June 11, 2015, accessed on July 30, 2015 .
  21. The first flying components. In: akaflieg-karlsruhe.de. Retrieved November 15, 2016 .
  22. Otto Schwab : Fraternity members fly! Frankfurt am Main 1939.
  23. History | Akaflieg Frankfurt. Retrieved February 3, 2017 .
  24. ^ Website of Akaflieg Kiel
  25. ^ Akaflieg Cologne
  26. Akaflieg Tübingen. Retrieved October 29, 2018 .
  27. Flugsportvereinigung Übersberg eV In: uebersberg.de. Retrieved October 29, 2018 .
  28. Beginner's course in gliding. In: sport.ifs.uni-tuebingen.de. Retrieved October 29, 2018 .
  29. Flight technical working group at the FH Aachen eV
  30. a b cf. Report books of Idaflieg 1978–1994, see also: Index of report books (incomplete)
  31. Information on Akaflieg Leoben