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Glider Snatch Pick-up
Glider snatch pick-up was a technique used by the Allies of World War II to launch a military glider with a low-flying powered aircraft (the tow or tug), which did not have to land. The snatching aircraft, typically a Douglas C-47 Skytrain ("Dakota"), had a 20 ft arm hanging down at a 45-degree angle, supporting a hook at the tip. The hook was attached to a steel rope attached to an automatic winch containing 1000 ft of steel cable. On flyover, the hook engaged in a square-shaped loop of a nylon tow rope supported on two poles about 20 ft apart and 10 ft off the ground. This loop was attached to a 180 ft nylon tow rope attached to the front of the glider. The special design of the hook meant it was less likely to snag the ground but would grab the loop. When the hook engaged in the loop, the rope initially paid out from the winch, and then gradually, a brake was automatically applied until up to 800 ft of cable had been paid out. This, and the stretch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allies Of World War II
The Allies, formally referred to as the United Nations from 1942, were an international military coalition formed during the Second World War (1939–1945) to oppose the Axis powers, led by Nazi Germany, Imperial Japan, and Fascist Italy. Its principal members by 1941 were the United Kingdom, United States, Soviet Union, and China. Membership in the Allies varied during the course of the war. When the conflict broke out on 1 September 1939, the Allied coalition consisted of the United Kingdom, France, and Poland, as well as their respective dependencies, such as British India. They were soon joined by the independent dominions of the British Commonwealth: Canada, Australia, New Zealand and South Africa. Consequently, the initial alliance resembled that of the First World War. As Axis forces began invading northern Europe and the Balkans, the Allies added the Netherlands, Belgium, Norway, Greece, and Yugoslavia. The Soviet Union, which initially had a nonaggression pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Military Glider
Military gliders (an offshoot of common gliders) have been used by the militaries of various countries for carrying troops (glider infantry) and heavy equipment to a combat zone, mainly during the Second World War. These engineless aircraft were towed into the air and most of the way to their target by military transport planes, e.g., C-47 Skytrain or Dakota, or bombers relegated to secondary activities, e.g., Short Stirling. Most military gliders do not soar, although there were attempts to build military sailplanes as well, such as the DFS 228. Once released from the tow craft near the front, they were to land on any convenient open terrain close to the target, hopefully with as little damage to the cargo and crew as possible as most landing zones (LZ) were far from ideal. The one-way nature of the missions meant that they were treated as semi-expendable leading to construction from common and inexpensive materials such as wood. Most nations seriously attempted to recover as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Douglas C-47 Skytrain
The Douglas C-47 Skytrain or Dakota (RAF, RAAF, RCAF, RNZAF, and SAAF designation) is a military transport aircraft developed from the civilian Douglas DC-3 airliner. It was used extensively by the Allies during World War II and remained in front-line service with various military operators for many years.Parker 2013, pp. 13, 35, 37, 39, 45-47. Design and development The C-47 differed from the civilian DC-3 by way of numerous modifications, including being fitted with a cargo door, hoist attachment and strengthened floor - along with a shortened tail cone for glider-towing shackles, and an astrodome in the cabin roof.Wilson, Stewart. ''Aircraft of WWII''. Fyshwick, ACT, Australia: Aerospace Publications Pty Ltd., 1998. . During World War II, the armed forces of many countries used the C-47 and modified DC-3s for the transport of troops, cargo, and wounded. The U.S. naval designation was R4D. More than 10,000 aircraft were produced in Long Beach and Santa Monica, California, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steel Rope
Steel wire rope (right hand lang lay) Wire rope is several strands of metal wire twisted into a helix forming a composite ''rope'', in a pattern known as ''laid rope''. Larger diameter wire rope consists of multiple strands of such laid rope in a pattern known as ''cable laid''. In stricter senses, the term ''wire rope'' refers to a diameter larger than , with smaller gauges designated cable or cords. Initially wrought iron wires were used, but today steel is the main material used for wire ropes. Historically, wire rope evolved from wrought iron chains, which had a record of mechanical failure. While flaws in chain links or solid steel bars can lead to catastrophic failure, flaws in the wires making up a steel cable are less critical as the other wires easily take up the load. While friction between the individual wires and strands causes wear over the life of the rope, it also helps to compensate for minor failures in the short run. Wire ropes were developed starting with mini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Winch
A winch is a mechanical device that is used to pull in (wind up) or let out (wind out) or otherwise adjust the tension of a rope or wire rope (also called "cable" or "wire cable"). In its simplest form, it consists of a spool (or drum) attached to a hand crank. Traditionally, winches on ships accumulated wire or rope on the drum; those that do not accumulate, and instead pass on the wire/rope (see yacht photo above), are called capstans. Despite this, sailboat capstans are most often referred to as winches. Winches are the basis of such machines as tow trucks, steam shovels and elevators. More complex designs have gear assemblies and can be powered by electric, hydraulic, pneumatic or internal combustion drives. It might include a solenoid brake and/or a Mechanical brake stretch wrapper, mechanical brake or ratchet (device), ratchet and pawl which prevents it unwinding unless the pawl is retracted. The rope may be stored on the winch. When trimming a line on a sailboat, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nylon
Nylon is a generic designation for a family of synthetic polymers composed of polyamides ( repeating units linked by amide links).The polyamides may be aliphatic or semi-aromatic. Nylon is a silk-like thermoplastic, generally made from petroleum, that can be melt-processed into fibers, films, or shapes. Nylon polymers can be mixed with a wide variety of additives to achieve many property variations. Nylon polymers have found significant commercial applications in fabric and fibers (apparel, flooring and rubber reinforcement), in shapes (molded parts for cars, electrical equipment, etc.), and in films (mostly for food packaging). History DuPont and the invention of nylon Researchers at DuPont began developing cellulose based fibers, culminating in the synthetic fiber rayon. DuPont's experience with rayon was an important precursor to its development and marketing of nylon. DuPont's invention of nylon spanned an eleven-year period, ranging from the initial research pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G-force
The gravitational force equivalent, or, more commonly, g-force, is a measurement of the type of force per unit mass – typically acceleration – that causes a perception of weight, with a g-force of 1 g (not gram in mass measurement) equal to the conventional value of gravitational acceleration on Earth, ''g'', of about . Since g-forces indirectly produce weight, any g-force can be described as a "weight per unit mass" (see the synonym specific weight). When the g-force is produced by the surface of one object being pushed by the surface of another object, the reaction force to this push produces an equal and opposite weight for every unit of each object's mass. The types of forces involved are transmitted through objects by interior mechanical stresses. Gravitational acceleration (except certain electromagnetic force influences) is the cause of an object's acceleration in relation to free fall. The g-force experienced by an object is due to the vector sum of all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combat Operations
Combat operations area - process is undertaken by armed forces during military campaigns, major operations, battles, and engagements to facilitate the setting of objectives, direction of combat, and assessment of the operation plan's success. The basic model of the combat operations area process includes five phases that seek to acquire targets and objectives, allocate and orient appropriate forces for successful engagement of the enemy, make decisions about doctrinal Doctrine (from la, doctrina, meaning "teaching, instruction") is a codification of beliefs or a body of teachings or instructions, taught principles or positions, as the essence of teachings in a given branch of knowledge or in a belief system ... approach to the engagement, execute the plan by engaging in combat, and conduct post-combat intelligence assessment of the success or failure of the operation's plan. References Military operations Military science Military theory {{mil-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1945 New Guinea Gremlin Special Rescue
The Gremlin Special was a Douglas C-47 Skytrain that crashed during a sightseeing flight over the Baliem Valley (also known as Shangri-La valley) in New Guinea in the eastern part of Netherlands Indies in 1945. The recovery of the three survivors from an isolated valley surrounded by mountains, enemy troops, and native inhabitants made worldwide news at the time and is the subject of the 2011 book ''Lost in Shangri-La'' by author Mitchell Zuckoff. Accident The Gremlin Special flew into the side of a mountain on May 13, 1945. Five passengers survived the initial wreck with two, Sergeant Laura Besley and Private Eleanor Hanna, succumbing to injuries the next day. The survivors were Corporal Margaret Hastings, Sergeant Kenneth Decker and Lieutenant John McCollom. The Baliem Valley was previously explored in 1938 by Richard Archbold, flying in a PBY-2. Although the press believed the survivors of the Gremlin Special crash to be the first outsiders to encounter the Dani people who ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Military Gliding
A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically authorized and maintained by a sovereign state, with its members identifiable by their distinct military uniform. It may consist of one or more military branches such as an army, navy, air force, space force, marines, or coast guard. The main task of the military is usually defined as defence of the state and its interests against external armed threats. In broad usage, the terms ''armed forces'' and ''military'' are often treated as synonymous, although in technical usage a distinction is sometimes made in which a country's armed forces may include both its military and other paramilitary forces. There are various forms of irregular military forces, not belonging to a recognized state; though they share many attributes with regular military forces, they are less often referred to as simply ''military''. A nation's military may f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
