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The earliest evidence for the parachute dates back to the Renaissance period.[3] The oldest parachute design appears in an anonymous manuscript from 1470s Renaissance Italy (British Museum Add. MSS 34,113, fol. 200v), showing a free-hanging man clutching a cross bar frame attached to a conical canopy.[4] As a safety measure, four straps run from the ends of the rods to a waist belt. The design is a marked improvement over another folio (189v), which depicts a man trying to break the force of his fall by the means of two long cloth streamers fastened to two bars which he grips with his hands.[5] Although the surface area of the parachute design appears to be too small to offer effective resistance to the friction of the air and the wooden base-frame is superfluous and potentially harmful, the revolutionary character of the new concept is obvious.[5] Only slightly later, a more sophisticated parachute was sketched by the polymath Leonardo da Vinci in his Codex Atlanticus (fol. 381v) dated to ca. 1485.[4] Here, the scale of the parachute is in a more favorable proportion to the weight of the jumper. Leonardo's canopy was held open by a square wooden frame, which alters the shape of the parachute from conical to pyramidal.[5] It is not known whether the Italian inventor was influenced by the earlier design, but he may have learned about the idea through the intensive oral communication among artist-engineers of the time.[6] The feasibility of Leonardo's pyramidal design was successfully tested in 2000 by Briton Adrian Nicholas and again in 2008 by Luigi Cani.[7] According to the historian of technology Lynn White, these conical and pyramidal designs, much more elaborate than early artistic jumps with rigid parasols in Asia, mark the origin of "the parachute as we know it."[3] Fausto Veranzio's 1595 parachute design titled "Flying Man" or "the Man with an Angel's Blessing" The Croatian inventor Fausto Veranzio (Faust Vrančić) (1551–1617) examined da Vinci's parachute sketch, and set out to implement one of his own. He kept the square frame, but replaced the canopy with a bulging sail-like piece of cloth that he came to realize decelerates the fall more effectively.[5] A now-famous depiction of a parachute that he dubbed Homo Volans (Flying Man), showing a man parachuting from a tower, presumably St Mark's Campanile in Venice, appeared in his book on mechanics, Machinae Novae (1615 or 1616), alongside a number of other devices and technical concepts.[8] It was widely believed that in 1617, Vrančić, then aged 65 and seriously ill, implemented his design and tested the parachute by jumping from St Mark's Campanile,[9] from a bridge nearby,[10] or from St Martin's Cathedral in Bratislava.[11][12] In various publications it was falsely claimed that the event was documented some thirty years later by John Wilkins, founder and secretary of the Royal Society in London in his book Mathematical Magick or, the Wonders that may be Performed by Mechanical Geometry, published in London in 1648.[10] However, in this book, John Wilkins wrote about flying, not about parachutes. He neither mentions Faust Vrančić nor a parachute jump nor any event in 1617, and doubts about this test along with no written evidence of its occurrence, lead to the conclusion that it never occurred, and was caused by a misreading of historical notes.[13] According to other publications, the Chinese began parachuting as long ago as the 1100s, while modern skydiving began with Jacques Garnerin from France and his experiments and public demonstrations in 1797.[14][15] Modern This section needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (January 2009) Louis-Sébastien Lenormand jumps from the tower of the Montpellier observatory, 1783. Illustration from the late 19th century First use of a frameless parachute, by André Garnerin in 1797 Schematic depiction of Garnerin's parachute, from an early nineteenth century illustration Picture published in a Dutch magazine De Prins der Geïllustreerde Bladen (February 18, 1911)[16] Gleb Kotelnikov and his invention, the knapsack parachute 18th and 19th centuries The modern parachute was invented in the late 18th century by Louis-Sébastien Lenormand in France, who made the first recorded public jump in 1783. Lenormand also sketched his device beforehand. Two years later, in 1785, Lenormand coined the word "parachute" by hybridizing the French prefix paracete, meaning to protect against, and chute, the French word for fall, to describe the device's function.[citation needed] Also in 1785, Jean-Pierre Blanchard demonstrated it as a means of safely disembarking from a hot-air balloon. While Blanchard's first parachute demonstrations were conducted with a dog as the passenger, he later claimed to have had the opportunity to try it himself in 1793 when his hot air balloon ruptured and he used a parachute to descend (this event was not witnessed by others). Subsequent development of the parachute focused on it becoming more compact. While the early parachutes were made of linen stretched over a wooden frame, in the late 1790s, Blanchard began making parachutes from folded silk, taking advantage of silk's strength and light weight. In 1797, André Garnerin made the first descent using such a parachute. Garnerin also invented the vented parachute, which improved the stability of the fall. Eve of World War I In 1907 Charles Broadwick demonstrated two key advancements in the parachute he used to jump from hot air balloons at fairs. His parachute was folded into a pack he wore on his back. And the parachute was pulled from the pack by a static line attached to the balloon. When Broadwick jumped from the balloon, the static line became taut, pulled the parachute from the pack, and then snapped.[17] In 1911 a successful test was done with a dummy at the Eiffel tower in Paris. The puppet's weight was 75 kg; the parachute's weight was 21 kg. The cables between puppet and the parachute were 9 m long.[16] On February 4, 1912, Franz Reichelt jumped to his death from the tower during initial testing of his wearable parachute. Also in 1911, Grant Morton made the first parachute jump from an airplane, a Wright Model B, at Venice Beach, California. The pilot of the plane was Phil Parmalee. Morton's device was of the "throw-out" type where he held the parachute in his arms as he left the aircraft. In the same year, a Russian inventor Gleb Kotelnikov invented the first knapsack parachute,[18] although Hermann Lattemann and his wife Käthe Paulus had been jumping with bagged parachutes in the last decade of the 19th century. Albert Berry collapses his parachute on Kinloch Field at Jefferson Barracks, Missouri, after his jump on March 1, 1912. In 1912, on a road near Tsarskoye Selo, years before it became part of St. Petersburg, Kotelnikov successfully demonstrated the braking effects of a parachute by accelerating a Russo-Balt automobile to the top speed, and then opening a parachute attached to the back seat, thus inventing also the drogue parachute.[18] On March 1, 1912, U.S. Army Captain Albert Berry made the first (attached-type) parachute jump in the United States from a fixed-wing aircraft, a Benoist pusher, while flying above Jefferson Barracks, St. Louis, Missouri. The jump utilized a "pack" style parachute stored or housed in a casing on the jumper's body. Štefan Banič from Slovakia invented the first actively used parachute, patenting it in 1914.[19] He tested his umbrella-like device by jumping from an airplane with it, and sold (or donated) the patent to the United States military, receiving very little money or fame for it.[20] On June 21, 1913, Georgia Broadwick became the first woman to parachute jump from a moving aircraft, doing so over Los Angeles, California.[21] In 1914, while doing demonstrations for the U.S. Army, Broadwick deployed her chute manually, thus becoming the first person to jump free-fall. World War I The first military use for the parachute was for use by artillery observers on tethered observation balloons in World War I. These were tempting targets for enemy fighter aircraft, though difficult to destroy, due to their heavy anti-aircraft defenses. Because it was difficult to escape from them, and dangerous when on fire due to their hydrogen inflation, observers would abandon them and descend by parachute as soon as enemy aircraft were seen. The ground crew would then attempt to retrieve and deflate the balloon as quickly as possible. The main part of the parachute was in a bag suspended from the balloon with the pilot wearing only a simple waist harness attached to the main parachute. When the balloon crew jumped the main part of the parachute was pulled from the bag by the crew's waist harness, first the shroud lines, followed by the main canopy. This type of parachute was first adopted on a large scale for their observation balloon crews by the Germans, and then later by the British and French. While this type of unit worked well from balloons, it had mixed results when used on fixed-wing aircraft by the Germans, where the bag was stored in a compartment directly behind the pilot. In many instances where it did not work the shroud lines became entangled with the spinning aircraft. Although a number of famous German fighter pilots were saved by this type of parachute, including Hermann Göring,[22] no parachutes were issued to Allied "heavier-than-air" aircrew, since it was thought at the time that if a pilot had a parachute he would jump from the plane when hit rather than trying to save the aircraft.[23] Airplane cockpits at that time also were not large enough to accommodate a pilot and a parachute, since a seat that would fit a pilot wearing a parachute would be too large for a pilot not wearing one. This is why the German type was stowed on the fuselage, rather than being of the "backpack" type. Weight was - at the very beginning - also a consideration, since planes had limited load capacity. Carrying a parachute served to lessen performance and reduced the useful offensive and fuel load. In the U.K., Everard Calthrop, a railway engineer (and breeder of Arab horses), invented and marketed through his Aerial Patents Company a "British Parachute" and the "Guardian Angle" parachute. Thomas Orde-Lees, known as the "Mad Major," demonstrated that parachutes could be used successfully from a low height (he jumped from Tower Bridge in London) which led to parachutes being used by the ballonists of the Royal Flying Corps, though they were not available for aircraft. In 1911, Solomon Lee Van Meter, Jr. of Lexington Kentucky, submitted for and in July 1916 received a patent for a backpack style parachute — the Aviatory Life Buoy.[24] His self-contained device featured a revolutionary quick-release mechanism — the ripcord — that allowed a falling aviator to expand the canopy only when safely away from the disabled aircraft.[25] In 1918 the German air service introduced a parachute designed by Unteroffizier Otto Heinecke, an airship ground crewman, and thus became the world's first, and at the time only, air service to introduce a standard parachute. Despite Germany equipping their pilots with parachutes, their efficiency was relatively poor. As a result, many pilots died while using them, including aces such as Oberleutnant Erich Lowenhardt (who fell from 3,600 metres (11,800 ft) after being accidentally rammed by another German aircraft) and Fritz Rumey who tested it in 1918, only to have it fail at a little over 900 m (3,000 ft). Out of the first 70 German airmen to bail out, around a third died.[26] These fatalities were mostly due to the chute or ripcord becoming entangled in the airframe of their spinning aircraft or because of harness failure, a problem fixed in later versions of the Heinecke parachute.[26] High as the failure rate was, carrying a Heinecke parachute certainly beat the alternative and the general effectiveness of the Heinecke parachute can be gauged by the fact that the French, British, American and Italian air services later based their first parachute designs on the Heinecke parachute to varying extents.[27] In the UK Sir Frank Mears who was serving as a Major in the Royal Flying Corps in France (Kite Balloon section) registered a patent in July 1918 for a parachute with a quick release buckle, known as the "Mears parachute" which was in common use from then onwards.[28] Post-World War I The experience with parachutes during the war highlighted the need to develop a design that could be reliably used to exit a disabled airplane. For instance, tethered parachutes did not work well when the aircraft was spinning. After the war, Major E. L. Hoffman of the United States Army led an effort to develop an improved parachute by bringing together the best elements of multiple parachute designs. Participants in the effort included Leslie Irvin and James Floyd Smith. The team eventually created the Airplane Parachute Type-A. This incorporated three key elements, storing the parachute in a soft pack worn on the back, as demonstrated by Charles Broadwick in 1906; a ripcord for manually deploying the parachute at a safe distance from the airplane, from a design by Albert Leo Stevens; and a pilot chute that draws the main canopy from the pack. In 1919, Irvin successfully tested the parachute by jumping from an airplane. The Type-A parachute was put into production and over time saved a number of lives.[17] Irvin became the first person to make a premeditated free-fall parachute jump from an airplane. An early brochure of the Irvin Air Chute Company credits William O'Connor as having become, on August 24, 1920 at McCook Field near Dayton, Ohio, the first person to be saved by an Irvin parachute.[29] Another life-saving jump was made at McCook Field by test pilot Lt. Harold H. Harris on October 20, 1922. Shortly after Harris' jump, two Dayton newspaper reporters suggested the creation of the Caterpillar Club for successful parachute jumps from disabled aircraft. In 1924 Gleb Kotelnikov of Russia became the first parachutist to apply the soft packing of a parachute instead of a hard casing.[30] Beginning with Italy in 1927, several countries experimented with using parachutes to drop soldiers behind enemy lines. The regular Soviet Airborne Troops were established as early as 1931 after a number of experimental military mass jumps starting from August 2, 1930.[18] Earlier the same year, in 1930, the first Soviet mass jumps led to the development of the parachuting sport in the Soviet Union.[18] By the time of World War II, large airborne forces were trained and used in surprise attacks, as in the Battle for The Hague, the first large-scale deployment of airborne troops in military history, by the Germans (whose operation failed totally)[31] and in 1941 Battle of Crete and in 1944 the Operation Market Garden, again in the Netherlands and again a complete failure, but still the largest airborne military operation ever carried out.[32] Aircraft crew were routinely equipped with parachutes for emergencies as well.[citation needed] In 1937, drag chutes were used in aviation for the first time, by the Soviet airplanes in the Arctic that were providing support for the famous polar expeditions of the era, such as the first manned drifting ice station North Pole-1. The drag chute allowed airplanes to land safely on smaller ice-floes.[18] Types Today's modern parachutes are classified into two categories — ascending and descending canopies. All ascending canopies refer to paragliders, built specifically to ascend and stay aloft as long as possible. Other parachutes, including ram-air non-elliptical, are classified as descending canopies by manufacturers. Some modern parachutes are classified as semi-rigid wings, which are maneuverable and can make a controlled descent to collapse on impact with the ground. Round An American paratrooper using an MC1-1C series "round" parachute Round parachutes are purely a drag device (that is, unlike the ram-air types, they provide no lift) and are used in military, emergency and cargo applications. These have large dome-shaped canopies made from a single layer of triangular cloth gores. Some skydivers call them "jellyfish 'chutes" because of the resemblance to the marine organisms. Modern sport parachutists rarely use this type. The first round parachutes were simple, flat circulars. These early parachutes suffered from instability caused by oscillations. A hole in the apex helped to vent some air and reduce the oscillations. Many military applications adopted conical, i.e., cone-shaped, or parabolic (a flat circular canopy with an extended skirt) shapes, such as the United States Army T-10 static-line parachute. A round parachute with no holes in it is more prone to oscillate, and is not considered to be steerable. Forward speed (5–13 km/h) and steering can be achieved by cuts in various sections (gores) across the back, or by cutting four lines in the back thereby modifying the canopy shape to allow air to escape from the back of the canopy, providing limited forward speed. Other modifications sometimes used are cuts in various sections (gores) to cause some of the skirt to bow out. Turning is accomplished by forming the edges of the modifications, giving the parachute more speed from one side of the modification than the other. This gives the jumpers the ability to steer the parachute (such as the United States Army MC series parachutes), enabling them to avoid obstacles and to turn into the wind to minimize horizontal speed at landing. Cruciform (square) The unique design characteristics of cruciform parachutes decreases oscillation (its user swinging back and forth) and violent turns during descent. This technology will be used by the United States Army as it replaces its older T-10 parachutes with T-11 parachutes under a program called Advanced Tactical Parachute System (ATPS). The ATPS canopy is a highly modified version of a cross/ cruciform platform and is square in appearance. The ATPS system will reduce the rate of descent by 30 percent from 21 feet per second (6.4 m/s) to 15.75 feet per second (4.80 m/s). The T-11 is designed to have an average rate of descent 14% slower than the T-10D, thus resulting in lower landing injury rates for jumpers. The decline in rate of descent will reduce the impact energy by almost 25% to lessen the potential for injury. Annular and pull down apex The Mars Science Laboratory descending under a ring parachute. RAF Typhoon using a parachute for braking after landing Animation showing a parachute release system A variation on the round parachute is the pull down apex parachute. Invented by a Frenchman named Pierre-Marcel Lemoigne,[33][34][35] it is called a Para-Commander canopy in some circles, after the first model of the type. It is a round parachute, but with suspension lines to the canopy apex that apply load there and pull the apex closer to the load, distorting the round shape into a somewhat flattened or lenticular shape. Some designs have the fabric removed from the apex to open a hole through which air can exit, giving the canopy an annular geometry. They also have decreased horizontal drag due to their flatter shape and, when combined with rear-facing vents, can have considerable forward speed. Rogallo wing Sport parachuting has experimented with the Rogallo wing, among other shapes and forms. These were usually an attempt to increase the forward speed and reduce the landing speed offered by the other options at the time. The ram-air parachute's development and the subsequent introduction of the sail slider to slow deployment reduced the level of experimentation in the sport parachuting community. The parachutes are also hard to build. Ribbon and Ring Ribbon and ring parachutes have similarities to annular designs. They are frequently designed to deploy at supersonic speeds. A conventional parachute would instantly burst upon opening at such speeds. Ribbon parachutes have a ring-shaped canopy, often with a large hole in the centre to release the pressure. Sometimes the ring is broken into ribbons connected by ropes to leak air even more. These large leaks lower the stress on the parachute so it does not burst or shred when it opens. Ribbon parachutes made of Kevlar are used on nuclear bombs, such as the B61 and B83.[36] Ram-air Most modern parachutes are self-inflating "ram-air" airfoils known as a parafoil that provide control of speed and direction similar to paragliders. Paragliders have much greater lift and range, but parachutes are designed to handle, spread and mitigate the stresses of deployment at terminal velocity. All ram-air parafoils have two layers of fabric; top and bottom, connected by airfoil-shaped fabric ribs to form "cells." The cells fill with high pressure air from vents that face forward on the leading edge of the airfoil. The fabric is shaped and the parachute lines trimmed under load such that the ballooning fabric inflates into an airfoil shape. This airfoil is sometimes maintained by use of fabric one-way valves called airlocks. The first ram-air test jump was performed by United States Navy test jumper Joe Crotwell. Varieties A United States Navy Parachute Team "Leap Frogs" jumper landing a "square" ram-air parachute Personal ram-air parachutes are loosely divided into two varieties — rectangular or tapered — commonly called "squares" or "ellipticals", respectively. Medium-performance canopies (reserve-, BASE-, canopy formation-, and accuracy-type) are usually rectangular. High-performance, ram-air parachutes have a slightly tapered shape to their leading and/or trailing edges when viewed in plan form, and are known as ellipticals. Sometimes all the taper is in the leading edge (front), and sometimes in the trailing edge (tail). Ellipticals are usually used only by sport parachutists. They often have smaller, more numerous fabric cells and are shallower in profile. Their canopies can be anywhere from slightly elliptical to highly elliptical, indicating the amount of taper in the canopy design, which is often an indicator of the responsiveness of the canopy to control input for a given wing loading, and of the level of experience required to pilot the canopy safely. The rectangular parachute designs tend to look like square, inflatable air mattresses with open front ends. They are generally safer to operate, because they are less prone to dive rapidly with relatively small control inputs, they are usually flown with lower wing loadings per square foot of area, and they glide more slowly. They typically have a lower glide ratio. Wing loading of parachutes is measured similarly to that of aircraft, comparing exit weight to area of parachute fabric. Typical wing loading for students, accuracy competitors, and BASE jumpers is less than one 5 kg per square meter — often 0.3 kilograms per square meter or less. Most student skydivers fly with wing loading below 5 kg per square meter. Most sport jumpers fly with wing loading between 5 and 7 kg per square meter, but many interested in performance landings exceed this wing loading. Professional Canopy pilots compete with wing loading of 10 to over 15 kilograms per square meter. While ram-air parachutes with wing loading higher than 20 kilograms per square meter have been landed, this is strictly the realm of professional test jumpers. Smaller parachutes tend to fly faster for the same load, and ellipticals respond faster to control input. Therefore, small, elliptical designs are often chosen by experienced canopy pilots for the thrilling flying they provide. Flying a fast elliptical requires much more skill and experience. Fast ellipticals are also considerably more dangerous to land. With high-performance elliptical canopies, nuisance malfunctions can be much more serious than with a square design, and may quickly escalate into emergencies. Flying highly loaded, elliptical canopies is a major contributing factor in many skydiving accidents, although advanced training programs are helping to reduce this danger. High-speed, cross-braced parachutes, such as the Velocity, VX, XAOS and Sensei, have given birth to a new branch of sport parachuting called "swooping." A race course is set up in the landing area for expert pilots to measure the distance they are able to fly past the 1.5-metre (4.9 ft) tall entry gate. Current world records exceed 180 metres (590 ft). Aspect ratio is another way to measure ram-air parachutes. Aspect ratios of parachutes are measured the same way as aircraft wings, by comparing span with chord. Low aspect ratio parachutes, i.e., span 1.8 times the chord, are now limited to precision landing competitions. Popular precision landing parachutes include Jalbert (now NAA) Para-Foils and John Eiff's series of Challenger Classics. While low aspect ratio parachutes tend to be extremely stable, with gentle stall characteristics, they suffer from steep glide ratios and a small tolerance, or "sweet spot", for timing the landing flare. Because of their predictable opening characteristics, parachutes with a medium aspect ratio around 2.1 are widely used for reserves, BASE, and canopy formation competition. Most medium aspect ratio parachutes have seven cells. High aspect ratio parachutes have the flattest glide and the largest tolerance for timing the landing flare, but the least predictable openings. An aspect ratio of 2.7 is about the upper limit for parachutes. High aspect ratio canopies typically have nine or more cells. All reserve ram-air parachutes are of the square variety, because of the greater reliability, and the less-demanding handling characteristics. A parachute is a device used to slow the motion of an object through an atmosphere by creating drag, or in the case of ram-air parachutes, aerodynamic lift. Parachutes are usually made out of light, strong cloth, originally silk, now most commonly nylon. Depending on the situation, parachutes are used with a variety of loads, including people, food, equipment, space capsules, and bombs. Drogue chutes are used to aid horizontal deceleration of a vehicle (a fixed-wing aircraft, or a drag racer), or to provide stability (certain types of light aircraft in distress;[1][2] tandem free-fall; or a space shuttle after a touchdown). |
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