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Akaflieg Darmstadt D-39
The Akaflieg Darmstadt D-39 was a single-seat motor glider derived from the D-38 sailplane. Built in Germany in the late 1970s, it was not intended for production and only one was constructed. Design and development The D-39 was a motorised version of the D-38 sailplane, with wings moved down from the latter's shoulder-wing position to the bottom of the fuselage. A Limbach SL 1700 flat four engine was conventionally mounted in the nose; the propeller could be removed but not folded away in flight. The wings, with 4° of dihedral, tail and monocoque fuselage were formed from glass fibre balsa sandwiches and the ailerons from glass fibre/ Klégécel foam sandwiches. The D-38 had an all moving T-tailplane, fitted with a Flettner tab. It landed on a retractable monowheel, fitted with a drum brake and assisted by a small, fixed tailwheel. The D-39 was first flown on 28 June 1979. By July 1982 it had been modified into the D-39b, with a greater span, revised wing roots and fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WikiProject Aircraft
A WikiProject, or Wikiproject, is a Wikimedia movement affinity group for contributors with shared goals. WikiProjects are prevalent within the largest wiki, Wikipedia, and exist to varying degrees within sister projects such as Wiktionary, Wikiquote, Wikidata, and Wikisource. They also exist in different languages, and translation of articles is a form of their collaboration. During the COVID-19 pandemic, CBS News noted the role of Wikipedia's WikiProject Medicine in maintaining the accuracy of articles related to the disease. Another WikiProject that has drawn attention is WikiProject Women Scientists, which was profiled by '' Smithsonian'' for its efforts to improve coverage of women scientists which the profile noted had "helped increase the number of female scientists on Wikipedia from around 1,600 to over 5,000". On Wikipedia Some Wikipedia WikiProjects are substantial enough to engage in cooperative activities with outside organizations relevant to the field at issue. For e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Akaflieg Darmstadt Aircraft
Akaflieg is an abbreviation for ''Akademische Fliegergruppe'', groups of aeronautical engineering students from individual German Technical Universities, pre and postwar, who design aircraft, often gliders. History Otto Lilienthal published his book ''Der Vogelflug als Grundlage der Fliegekunst (Birdflight as the Basis of Aviation)'' in 1889. This described the basics of modern aerodynamics and aircraft construction. Lilienthal then made many successful flights starting in 1891. However attention then shifted to powered flight after World War I. Gliding re-emerged as a sport after the war because the building of powered aircraft was restricted in Germany by the Treaty of Versailles. The main originator of the gliding movement was Oskar Ursinus Carl Oskar Ursinus (11 March 1877 – 6 July 1952) was a pioneer of German aviation and is remembered mainly for his contributions to sailplane designs and the sport of gliding. He has been nicknamed the ''Rhönvater'' ("Rhön fat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1970s German Sailplanes
Year 197 ( CXCVII) was a common year starting on Saturday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Magius and Rufinus (or, less frequently, year 950 ''Ab urbe condita''). The denomination 197 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * February 19 – Battle of Lugdunum: Emperor Septimius Severus defeats the self-proclaimed emperor Clodius Albinus at Lugdunum (modern Lyon). Albinus commits suicide; legionaries sack the town. * Septimius Severus returns to Rome and has about 30 of Albinus's supporters in the Senate executed. After his victory he declares himself the adopted son of the late Marcus Aurelius. * Septimius Severus forms new naval units, manning all the triremes in Italy with heavily armed troops for war in the East. His soldiers embark on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motor Gliders
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power generation), heat energy (e.g. geothermal), chemical energy, electric potential and nuclear energy (from nuclear fission or nuclear fusion). Many of these processes generate heat as an intermediate energy form, so heat engines have special importance. Some natural processes, such as atmospheric convection cells convert environmental heat into motion (e.g. in the form of rising air currents). Mechanical energy is of particular importance in transportation, but also plays a role in many industrial processes such as cutting, grinding, crushing, and mixing. Mechanical heat engines convert heat into work via various thermodynamic processes. The internal combustion engine is perhaps the most common example of a mechanical heat engine, in which he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flat Four
A flat-four engine, also known as a horizontally opposed-four engine, is a four-cylinder piston engine with two banks of cylinders lying on opposite sides of a common crankshaft. The most common type of flat-four engine is the boxer-four engine, each pair of opposed pistons moves inwards and outwards at the same time. A boxer-four engine has perfect primary and secondary balance, however, the two cylinder heads means the design is more expensive to produce than an inline-four engine. Boxer-four engines have been used in cars since 1897, especially by Volkswagen and Subaru. They have also occasionally been used in motorcycles and frequently in aircraft. Cessna and Piper use flat four engines from Lycoming and Continental in the most common civil aircraft in the world - the Cessna 172, and Piper Cherokee, while many ultralight and LSA planes use versions of the Rotax 912. Design Most flat-four engines are designed so that each pair of opposing pistons moves inwards and outw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limbach SL 1700E
The Limbach L1700 is a series of type certified German aircraft engines, designed and produced by Limbach Flugmotoren of Königswinter for use in light aircraft and motorgliders.Bayerl, Robby; Martin Berkemeier; et al: ''World Directory of Leisure Aviation 2011-12'', pages 240-241. WDLA UK, Lancaster UK, 2011. ISSN 1368-485X The series were originally designated as the ''SL1700'' under its former certification and was changed to ''L1700'' by company Service Bulletin no. 17. Design and development The L1700 is a four-cylinder four-stroke, horizontally-opposed air-cooled, gasoline direct-dive engine design, based upon the Volkswagen air-cooled engine. It employs a single magneto ignition, one carburettor A carburetor (also spelled carburettor) is a device used by an internal combustion engine to control and mix air and fuel entering the engine. The primary method of adding fuel to the intake air is through the venturi tube in the main meterin ..., is lubricated by a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hoffmann Propeller
Hoffman Propeller is a German manufacturer of aircraft propellers. The company headquarters is located at Rosenheim in Bavaria, Germany.Purdy, Don: ''AeroCrafter - Homebuilt Aircraft Sourcebook'', page 84. BAI Communications. The company makes design, manufacture and maintain propellers with blades in wooden composite construction for needed purposes, mainly for the general aviation, hovercraft and any special applications such as blades for wind tunnels the automotive industries. By the version of Aircraft Turboprop Propeller System Market Outlook, the company was one of the major market players. History Established in 1955 the company initially designed and produced propellers for motor gliders with a staff of six. The company expanded into the field of general aviation propeller overhaul and today, with a staff of 57, the company offers a wide range of propeller services including new certified replacements for vintage aircraft where the original propeller type is unavailab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drum Brake
A drum brake is a brake that uses friction caused by a set of shoes or pads that press outward against a rotating cylinder-shaped part called a brake drum. The term ''drum brake'' usually means a brake in which shoes press on the inner surface of the drum. When shoes press on the outside of the drum, it is usually called a '' clasp brake''. Where the drum is pinched between two shoes, similar to a conventional disc brake, it is sometimes called a ''pinch drum brake'', though such brakes are relatively rare. A related type called a band brake uses a flexible belt or "band" wrapping around the outside of a drum. History The modern automobile drum brake was first used in a car made by Maybach in 1900, although the principle was only later patented in 1902 by Louis Renault. He used woven asbestos lining for the drum brake lining, as no alternative dissipated heat like the asbestos lining, though Maybach had used a less sophisticated drum brake. In the first drum brakes, levers a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monowheel
A monowheel, or uniwheel, is a one-wheeled single-track vehicle similar to a unicycle. Hand-cranked and pedal-powered monowheels were patented and built in the late 19th century; most built in the 20th and 21st century have been motorized. Some modern builders refer to these vehicles as monocycles, though that term is also sometimes used to describe motorized unicycles. The world speed record for a motorized monowheel is 98.464 km/h (61.18 mph). Stability Similar to bicycles, monowheels are stable in the direction of travel, but have limited horizontal stability. This is in contrast to unicycles which are unstable in both directions. Monowheels have also been found to have a lower speed required for stability when compared to unicycles. A monowheel remains upright due to gyroscopic effects, but its lack of stability makes it highly dependent on forward momentum and the balance of the rider, who must maintain stability while steering. Over the history of the monow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flettner Tab
__NOTOC__ A servo tab is a small hinged device installed on an aircraft control surface to assist the movement of the control surfaces. Introduced by the German firm Flettner, servo tabs were formerly known as Flettner tabs. Servo tabs are not true servomechanisms, as they do not employ negative feedback to keep the control surfaces in a desired position; they only provide a mechanical advantage to the pilot. Servo tabs A servo tab, or balance tab, moves in the direction opposite to the desired movement of the control surface. It deflects airflow, generating force on the whole control surface in the desired direction. The tab has a leverage advantage, being located well aft of the control surface hinge line, and thus its airflow deflection moves the control surface in the opposite direction, overcoming the resistance generated by the airflow deflection of the control surface. This has the effect of reducing the control force required from the pilot to move the controls. In s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
