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Petróczy-Kármán-Žurovec
Petróczy, Kármán and Žurovec were Hungarian and Czech engineers who worked on helicopter development immediately before and during World War I in Budapest. Between them they produced two experimental prototypes, the PKZ-1 and PKZ-2, intended to replace the dangerous hydrogen-filled observation balloons then in use. As such, these craft were tethered on long cables and were not intended to fly freely. After the war other engineers, notably Oszkár von Asboth, further developed the design.Grosz (1978) History In 1916, the aviator and Austro-Hungarian Army Colonel István Petróczy proposed an electrically driven rotorcraft to replace the dangerously flammable observation balloon. His original concept was for the electric motor to be supplied by a dynamo driven by an internal combustion engine. Austro-Daimler were at that time developing a lightweight electric motor for aircraft use, but would take several years to develop one able to handle the electrical power required. A m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicopters
A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of STOL (Short TakeOff and Landing) or STOVL (Short TakeOff and Vertical Landing) aircraft cannot perform without a runway. In 1942, the Sikorsky R-4 became the first helicopter to reach full-scale production.Munson 1968.Hirschberg, Michael J. and David K. Dailey"Sikorsky". ''US and Russian Helicopter Development in the 20th Century'', American Helicopter Society, International. 7 July 2000. Although most earlier designs used more than one main rotor, the configuration of a single main rotor accompanied by a vertical anti-torque tail rotor (i.e. unicopter, not to be confused with the single-blade monocopter) has become the most common h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oszkár Asboth
Asbóth Oszkár, also rendered as Oskar Asboth, (31 March 1891 in Pankota – 27 February 1960 in Budapest) was a Hungarian aviation engineer often credited with the invention of the helicopter. His machine used stacked counterrotating propellers; Asbóth never solved the problem of in-flight stability, this was left to others. He grew up in Arad, which is today part of Romania, and at a very young age began to explore the possibilities of human flight. Like most of the pioneers of aviation he was confronted with the challenge of stabilising the movement of the aeroplane, and to this end developed numerous devices. He sent one of his devices to the headquarters of the Air Force in Vienna. As a result he made something of a name for himself while still very young. For his military service he was sent to the propeller development facility of Fischamend. During the First World War he was involved in the selection of propellers for the various types of aeroplane engine. He had ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theodore Von Kármán
Theodore von Kármán ( hu, ( szőllőskislaki) Kármán Tódor ; born Tivadar Mihály Kármán; 11 May 18816 May 1963) was a Hungarian-American mathematician, aerospace engineer, and physicist who was active primarily in the fields of aeronautics and astronautics. He was responsible for many key advances in aerodynamics, notably on supersonic and hypersonic airflow characterization. He is regarded as an outstanding aerodynamic theoretician of the 20th century. Early life Theodore von Kármán was born into a Jewish family in Budapest, Austria-Hungary, as Kármán Tódor, the son of Helen (Kohn, hu, Kohn Ilka) and Mór Kármán. One of his ancestors was Rabbi Judah Loew ben Bezalel. He studied engineering at the city's Royal Joseph Technical University, known today as Budapest University of Technology and Economics. After graduating in 1902 he moved to the German Empire and joined Ludwig Prandtl at the University of Göttingen, where he received his doctorate in 1908. He taug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focke-Achgelis Fa 330
The Focke-Achgelis Fa 330 ''Bachstelze'' ( en, Wagtail) was a type of rotary-wing kite, known as a rotor kite. They were towed behind German U-boats during World War II to allow a lookout to see further. Development Because of their low profile in the water, submarines could not see more than a few miles over the ocean. To solve this, the German admiralty considered a number of different options, including a folding seaplane (Arado Ar 231). In the end, they chose the Fa 330, a simple, single-seat autogyro kite with a three-bladed rotor. The Fa 330 could be deployed to the deck of the submarine by two people and was tethered to the U-boat by a 150 m (500 ft) cable. The airflow on the rotors as the boat motored along on the surface would spin them up. The kite would then be deployed behind the U-boat with its observer-pilot aboard, raising him approximately 120 meters above the surface and allowing him to see much farther — about 25 nautical miles (46 km) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicopter
A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of STOL (Short TakeOff and Landing) or STOVL (Short TakeOff and Vertical Landing) aircraft cannot perform without a runway. In 1942, the Sikorsky R-4 became the first helicopter to reach full-scale production.Munson 1968.Hirschberg, Michael J. and David K. Dailey"Sikorsky". ''US and Russian Helicopter Development in the 20th Century'', American Helicopter Society, International. 7 July 2000. Although most earlier designs used more than one main rotor, the configuration of a single main rotor accompanied by a vertical anti-torque tail rotor (i.e. unicopter, not to be confused with the single-blade monocopter) has become the most comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A PKZ-helikopter 50 Méter Magasságban
A, or a, is the first letter and the first vowel of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''a'' (pronounced ), plural ''aes''. It is similar in shape to the Ancient Greek letter alpha, from which it derives. The uppercase version consists of the two slanting sides of a triangle, crossed in the middle by a horizontal bar. The lowercase version can be written in two forms: the double-storey a and single-storey ɑ. The latter is commonly used in handwriting and fonts based on it, especially fonts intended to be read by children, and is also found in italic type. In English grammar, " a", and its variant " an", are indefinite articles. History The earliest certain ancestor of "A" is aleph (also written 'aleph), the first letter of the Phoenician alphabet, which consisted entirely of consonants (for that reason, it is also called an abjad to distinguish it fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coaxial Rotor Helicopters
In geometry, coaxial means that several three-dimensional linear or planar forms share a common axis. The two-dimensional analog is '' concentric''. Common examples: A coaxial cable is a three-dimensional linear structure. It has a wire conductor in the centre (D), a circumferential outer conductor (B), and an insulating medium called the dielectric (C) separating these two conductors. The outer conductor is usually sheathed in a protective PVC outer jacket (A). All these have a common axis. The dimension and material of the conductors and insulation determine the cable's characteristic impedance and attenuation at various frequencies. Coaxial rotors are a three-dimensional planar structure: a pair of helicopter rotors (wings) mounted one above the other on concentric shafts, with the same axis of rotation (but turning in opposite directions). In loudspeaker design, coaxial speakers A coaxial loudspeaker is a loudspeaker system in which the individual driver units radiate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of Aviation
The history of aviation extends for more than two thousand years, from the earliest forms of aviation such as kites and attempts at tower jumping to supersonic and hypersonic flight by powered, heavier-than-air jets. Kite flying in China dates back to several hundred years BC and slowly spread around the world. It is thought to be the earliest example of man-made flight. Leonardo da Vinci's 15th-century dream of flight found expression in several rational designs, but which relied on poor science. The discovery of hydrogen gas in the 18th century led to the invention of the hydrogen balloon, at almost exactly the same time that the Montgolfier brothers rediscovered the hot-air balloon and began manned flights. Various theories in mechanics by physicists during the same period of time, notably fluid dynamics and Newton's laws of motion, led to the foundation of modern aerodynamics, most notably by Sir George Cayley. Balloons, both free-flying and tethered, began to be use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hungarian Engineers
Hungarian may refer to: * Hungary, a country in Central Europe * Kingdom of Hungary, state of Hungary, existing between 1000 and 1946 * Hungarians, ethnic groups in Hungary * Hungarian algorithm, a polynomial time algorithm for solving the assignment problem * Hungarian language Hungarian () is an Uralic language spoken in Hungary and parts of several neighbouring countries. It is the official language of Hungary and one of the 24 official languages of the European Union. Outside Hungary, it is also spoken by Hungarian ..., a Finno-Ugric language spoken in Hungary and all neighbouring countries * Hungarian notation, a naming convention in computer programming * Hungarian cuisine, the cuisine of Hungary and the Hungarians See also * * {{disambiguation Language and nationality disambiguation pages ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allied Control Commission
Following the termination of hostilities in World War II, the Allies were in control of the defeated Axis countries. Anticipating the defeat of Germany and Japan, they had already set up the European Advisory Commission and a proposed Far Eastern Advisory Commission to make recommendations for the post war period. Accordingly, they managed their control of the defeated countries through Allied Commissions, often referred to as Allied Control Commissions (ACC), consisting of representatives of the major Allies. Italy Under the provisions of Article 37 in thArmistice with Italy Instrument of Surrender September 29, 1943, the Control Commission for Italy was established on November 10, 1943, and was dismantled on Dicember 14, 1947, following the conclusion of the Italian Peace Treaty at the Paris Peace Conference in 1947. Romania The Armistice Agreement with Rumania signed on September 12, 1944, established, among others, the following: * Article 1 ''"As from August 24, 1944, at fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Direct Current
Direct current (DC) is one-directional flow of electric charge. An electrochemical cell is a prime example of DC power. Direct current may flow through a conductor such as a wire, but can also flow through semiconductors, insulators, or even through a vacuum as in electron or ion beams. The electric current flows in a constant direction, distinguishing it from alternating current (AC). A term formerly used for this type of current was galvanic current. The abbreviations ''AC'' and ''DC'' are often used to mean simply ''alternating'' and ''direct'', as when they modify ''current'' or ''voltage''. Direct current may be converted from an alternating current supply by use of a rectifier, which contains electronic elements (usually) or electromechanical elements (historically) that allow current to flow only in one direction. Direct current may be converted into alternating current via an inverter. Direct current has many uses, from the charging of batteries to large power sup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
