This article is about the device. For sports and other activities involving a parachute, see Parachuting. For other uses, see Parachute (disambiguation).
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A parachute is a device used to slow the motion of an object through an atmosphereby creating drag (or in the case of ram-air parachutes, aerodynamic lift). Parachutes are usually made out of light, strong fabric, originally silk, now most commonly nylon. They are typically dome-shaped, but vary, with rectangles, inverted domes, and others found. A variety of loads are attached to parachutes, including people, food, equipment, space capsules, and bombs.
A drogue chute is used to aid horizontal deceleration of a vehicle including fixed-wing aircraft and drag racers, provide stability, as to assist certain types of light aircraft in distress,[1][2] tandem free-fall; and as a pilot triggering deployment of a larger parachute.
Early Renaissance
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 Library, Add MS 34113, fol. 200v), showing a free-hanging man clutching a crossbar frame attached to a conical canopy.[4] As a safety measure, four straps ran 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 air resistance and the wooden base-frame is superfluous and potentially harmful, the basic concept of a working parachute is apparent.[5]
Shortly after, 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][7] The feasibility of Leonardo's pyramidal design was successfully tested in 2000 by Briton Adrian Nicholas and again in 2008 by the Swiss skydiver Olivier Vietti-Teppa.[8] 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]
The Venetian polymath and inventor Fausto Veranzio (1551–1617) examined da Vinci's parachute sketch and kept the square frame but replaced the canopy with a bulging sail-like piece of cloth that he came to realize decelerates a 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 ("New Machines", published in 1615 or 1616), alongside a number of other devices and technical concepts.[9]
It was once widely believed that in 1617, Veranzio, then aged 65 and seriously ill, implemented his design and tested the parachute by jumping from St Mark's Campanile,[10] from a bridge nearby,[11] or from St Martin's Cathedral in Bratislava.[12] In various publications it was incorrectly claimed 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.[11] However, Wilkins wrote about flying, not parachutes, and does not mention Veranzio, a parachute jump, or any event in 1617. Doubts about this test, which include a lack of written evidence, suggest it never occurred, and was instead a misreading of historical notes.[13]
18th and 19th centuries
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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 an Italian prefix para, an imperative form of parare = to avert, defend, resist, guard, shield or shroud, from paro = to parry, and chute, the French word for fall, to describe the aeronautical device's real function.
Also in 1785, Jean-Pierre Blancharddemonstrated 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 linenstretched 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 of a "frameless" parachute covered in silk.[14] In 1804 Jérôme Lalande introduced a vent in the canopy to eliminate violent oscillations.[14]
Eve of World War I
In 1907 Charles Broadwick demonstrated two key advances in the parachute he used to jump from hot air balloons at fairs: he folded his parachute into a pack he wore on his backand 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.[16]
In 1911 a successful test took place with a dummy at the Eiffel tower in Paris. The puppet's weight was 75 kg (165 lb); the parachute's weight was 21 kg (46 lb). The cables between puppet and the parachute were 9 m (30 ft) long.[15] 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 piloted by Phil Parmalee, at Venice Beach, California. 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, Russian Gleb Kotelnikov invented the first knapsack parachute,[17] although Hermann Lattemann and his wife Käthe Paulus had been jumping with bagged parachutes in the last decade of the 19th century.
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 its top speed and then opening a parachute attached to the back seat, thus also inventing the drogue parachute.[17]
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 knapsack style parachute stored or housed in a casing on the jumper's body.
Štefan Banič, an immigrant in the United States, from Slovakia patented an umbrella-like design in 1914[18] and sold (or donated) the patent to the United States military which later on modified his design, resulting in the first military parachute.[19][20] Banič had been the first person to patent the parachute[21] and his design was the first to properly function in the 20th century.[21]
On June 21, 1913, Georgia Broadwick became the first woman to parachute-jump from a moving aircraft, doing so over Los Angeles, California.[22] 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 of the parachute was 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,[23] no parachutes were issued to the crews of Allied "heavier-than-air" aircraft, since it was thought that if a pilot had a parachute he would jump from the plane when hit rather than trying to save the aircraft.[24]
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 in 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 impeded performance and reduced the useful offensive and fuel load.
In the UK, Everard Calthrop, a railway engineer and breeder of Arab horses, invented and marketed through his Aerial Patents Company a "British Parachute" and the "Guardian Angel" 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)[25][26] which led to parachutes being used by the balloonists 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.[27] 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.[28]
Otto Heinecke, a German airship ground crewman, designed a parachute which the German air service introduced in 1918, becoming the world's first air service to introduce a standard parachute. Although many pilots were saved by these, their efficacy was relatively poor. Out of the first 70 German airmen to bail out, around a third died,[29] including aces such as Oberleutnant Erich Löwenhardt (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). 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.[29]
The French, British, American and Italian air services later based their first parachute designs on the Heinecke parachute to varying extents.[30]
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.[31]
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 Edward 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.[16] The effort was recognized by the awarding of the Robert J. Collier Trophy to Major Edward L. Hoffman in 1926.[32]
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.[33]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 Clubfor successful parachute jumps from disabled aircraft.
On July 4, 1924 (patent No.1607) Gleb Kotelnikov of Russia became the first parachutist to apply the soft packing of a parachute instead of a hard casing.[34]
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.[17] Earlier the same year, the first Soviet mass jumps led to the development of the parachuting sport in the Soviet Union.[17] By the time of World War II, large airborne forceswere trained and used in surprise attacks, as in the battles for Fort Eben-Emael and The Hague, the first large-scale, opposed landings of paratroopers in military history, by the Germans.[35] This was followed later in the war by airborne assaults on a larger scale, such as the Battle of Crete and Operation Market Garden, the latter being the largest airborne military operation ever.[36] Aircraft crew were routinely equipped with parachutes for emergencies as well.
In 1937, drag chutes were used in aviation for the first time, by Soviet airplanes in the Arcticthat were providing support for the 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
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