Parachute - History
Leonardo da Vinci (1452-1519), between 1483 and 1485, sketched an idea churning about in his ever busy mind. As early as 1485 to 1495 DaVinci had an idea for a device (a "tent roof") that would let someone down safely from high buildings, but it stayed a concept, never getting off the drawing board. The crude sketch depicted a large four-sided clothcovered framework resembling a pyramid in shape. Attached to each lower corner of the shape were four long suspension lines secured together at a confluence formed at the lower ends of the lines. In use, da Vinci showed how someone would hang by hands from the line confluence and be lowered beneath the open shape to the ground. It would be up to others to make the actual tests.
Through ensuing centuries, as parachutes did come into existence, and da Vinci's minimal effort was reviewed, he came to be credited with being "the father of the parachute." It was not until long past his death that the term "parachute" was coined. [Five hundred years later, in the year 2000, the British skydiver Adrian Nicholas resolved to put da Vinci's idea to the test. Nicholas and the da Vinci parachute successfully flew on July 25, 2000.]
There were many experimental parachute descents made before the turn of the twentieth century. Fauste Veranzio constructed a device similar to da Vinci's drawing and jumped from a tower in Venice in 1617. It is generally agreed that in 1783 Sebastian Lenormand of France did make a successful jump from a tower of some height using a fourteen-foot-diameter canopy in an effort to develop a way to escape buildings on fire. The de Montgolfier brothers, Joseph and Étienne, tested a variety of parachute designs. It is said that in one of their experiments they dropped sheep on a seven-foot canopy without injury to the befuddled animal. In the next decade the Montgolfiers concentrated on balloon design, development, and testing. But it was slow work. Their first successful ascent was an unmanned hot-air balloon on June 5, 1783, at Annonay, France. They ultimately developed a balloon capable of lifting a human. Their place in history became assured, and as balloons improved, and people went higher and higher and could fall greater distances, interest in parachute design and testing rapidly increased.
In October 1797, Jacques-André Garnerin was credited with being the first genuine parachutist by jumping with a parachute without a rigid frame from a hydrogen balloon over London, England. One of Garnerin's balloon jumps from 8000 feet, a very high altitude for the time, was observed by a French astronomer, Lalandes. As the parachute descended, severe oscillations were induced in the canopy. Lalandes suggested cutting a small hole near the apex of the canopy to inhibit the oscillations. This modification is now known as the vent and does indeed dramatically reduce canopy oscillations. Garnerin actually crossed the English Channel in 1802 in a balloon and landed in England by parachute.
Over ensuing years, others in France, Poland, and England valorously tested their ideas- and progress was made, often at a dear cost. But the price was considered worthwhile to each of the experimenters and they continued work. Robert Cocking distinguished himself by becoming parachuting's first fatality when he fell to his death in 1837. Cocking jumped an inverted coneshaped parachute (point down) from 5000 ft.
In 1890, Käthe Paulus of Germany was the first parachutist billed as a "professional." Her rig was a parachute described as a "folded exhibition attached-type," commonly used by early balloon jumpers. Suspension lines from the canopy were attached to a concentric wooden ring with a mesh-like center similar in appearance to that of a tennis racket. For stowage during ascent the wooden ring was secured close to the bottom of the canopy by two "tie lines" and the slack suspension lines were loosely accordianfolded on the mesh surface. The apex of the canopy was securely attached to the balloon by means of a "break cord" and when the hot-air lifting device reached a desired altitude Käthe used a knife to cut the connecting break cord. The canopy easily and quickly inflated as she dropped and landed to admiring, rousing cheers.
In 1901, Charles Broadwick, an American, designed a parachute assembly he defined as a "pack on the aviator." The canopy was enclosed in a fabric container that was laced closed with break cord. The pack was part of a fabric assembly that was put on in the same manner as one dons a coat, with arms through armholes of a sleeveless "jacket." The jacket extended below one's buttocks, in the style of a car-coat, and was wrapped about a user's lower body, then secured vertically along the user's torso. In use, a parachutist fastened a static line to the aircraft, with the opposite end of the static line secured to the lacing on the pack on the user's back. Simply by falling away from the aircraft, the force exerted by a jumper's weight was sufficient to break the lacing on the back pack and the canopy (also fastened by a break cord to the static line) deployed as the jumper fell away, with the break cord snapping in two when forces on the deployed system were adequate.
Broadwick's foster-daughter, Georgia Thompson Broadwick, was known as "Tiny" because of her small size and eighty-pound weight. She made her first parachute jump at age fifteen from a hot-air balloon over Raleigh, North Carolina in 1908. Five years later she became the first woman to jump from an airplane when Glenn Martin (who went on to become a renowned aircraft designer and manufacturer) piloted her over Los Angeles. Tiny is reported to have made the world's first free-fall jump with a manually operated parachute in 1913. Later the same year she was the first woman to make an intentional water jump when she parachuted from a hydroplane into Lake Michigan. In all, Tiny made 1,100 parachute jumps, the last one in 1922, and she lived into her eighties. On March 15, 1915, at North Island, San Diego, California, Tiny Broadwick greatly impressed military personnel with her courage and skill as she demonstrated a pack parachute, but the officials took no real interest in the Broadwick design as an aerial life preserver.
In World War One countless balloonists and scores of pilots rescued themselves in perilous situations. The Germans were the first aerial combatants to realize it was an enormous waste of personnel to place a soldier in an extraordinarily risky situation without a life-saving alternative. However, that realization was not immediate with the start of hostilities. Nonetheless, the Germans learned quickly and took hasty measures to save much-needed pilots and balloon observers. Later, much later, the Allies reluctantly reached the same decision.
With the advent of aerial warfare, Allied air commanders were opposed to providing parachutes to pilots, worried that wearing a parachute might encourage early, unnecessary abandonment of only slightly damaged aircraft; after all, aircraft were at a premium, but there were a lot of military men who wanted to pilot flying machines. It certainly was a more glamorous aspect of war. Implementation was another matter, and a great deal of time was needed before parachutes could be manufactured and supplied and before lives could be saved. Balloon-type parachutes were available but the pilots refused to use them for a variety of reasons. When released from a speeding airplane, a parachute could rip in the windblast or snag in the airplane's tail. Falling at the same rate of speed as the pilot, the plane could collide with the falling man. It was also possible for the parachute to get tangled in the propeller blades. Many pilots considered it their duty to go down with the ship or to ride the crippled airplane in for a crash landing.
Parachutes were initially forbidden as flying equipment. However, by one account, in the fall of 1916 an Austrian pilot on the Russian front made a parachute jump from a burning plane, the first practical application of the parachute to military requirements. According to another story, in 1917 a German pilot ignored the prohibition, bought a personal static-line deployed rig, wore it on combat missions, and successfully bailed out of his unmanageable plane. In any event, some pilots spent their own money for life-saving equipment. Commanders gradually understood that destroyed airplanes could easily be replaced but replacement pilots were difficult to recruit, their training was time-consuming, and financial costs were greater.
Parachutes were then authorized by most air services late in the war. However, military parachute inventories were extremely limited. To save pilots, the Germans equipped planes with static line-operated parachutes. Aviators wearing only a harness simply leaped out. After falling only a few feet, he would reach the end of a line attached to lacing on a container fastened outside the cockpit. His weight would break the lacing, the parachute deployed, and he floated down. There were many complications: spinning aircraft would snag a deploying parachute; tumbling wreckage sometimes tore apart canopy fabric or suspension lines; flames racing along a fuselage damaged a container and canopy, making it useless; or fire would lick at a canopy for the seconds it took for fabric to leave the container. However, many World War One flyers and balloonists did ultimately owe their lives to parachutes.
Before the end of the war in November 1918, the U.S. Army formed a Parachute Section in October at Wilbur Wright Field in Dayton, Ohio, to work out a practical parachute for emergency escape from aircraft. The unit was soon transferred to nearby McCook Field, with its superior facilities for testing. J. Floyd Smith and several others with parachuting experience were assigned to the new unit and in early 1919 Major E.L. Hoffman, was given command of the parachute development team.
Parachutes from around the world were drop-tested and it didn't take long to decide to replace so-called "automatic" static-linedeployed parachutes with manually operated freefall rigs that could be operated by a user after falling clear of a crippled machine. Leslie L. Irvin, who had a small parachute business in Buffalo, New York, submitted a canopy design when bids were solicited by the U.S. Army, but it was rejected because the canopy fabric was cotton and would be deployed by a falling jumper's weight, as done by balloon passengers.
Smith and others had advocated a "pack-on-the-back" that could be deployed by pulling a ripcord. Many designs from around the world were submitted to the new Parachute Section and tested, with most rejected. Some features were incorporated into a prototype Model "A" parachute with a 30-foot diameter silk canopy. It was stringently "dummy"-tested for strength and durability, including drops from planes falling in intentional spins. Floyd smith designed the most promising. This was a parachute pack that used a flap system to hold the parachute canopy. When the ripcord was pulled manually, it pulled back the flaps through a system of cords and allowed the parachute canopy to deploy into the airstream.
Major Hoffman designated Leslie Irvin to make a live test jump. He was a well known parachutist and parachute-maker, with a lot of aviation background (his nickname was "Sky-Hi"). The parachute he was to use was made of silk and had been droptested eleven times and remained in airworthy condition. On April 28th, 1919 Irvin boarded a DeHavilland D-9 biplane piloted by Smith. The plane climbed to 1,500 feet and at 80 miles per hour Irvin jumped over the side, fell a couple seconds, and briskly pulled the ripcord handle from its harness-mounted pocket. In an eye-blink the canopy streamed out and filled in one and two-fifths seconds.
This was the start of the Irving Air Chute Company. (A typographic error of adding a "g" to the Irvin name led to the company name and it remained so for many years.) A significant milestone in parachuting had been reached. The Model "A" evolved into the Model "S" parachute assembly that was the basis of parachute configurations for many years. The military C-9 canopy widely used currently is a copy of the Model "S" canopy.
The parachute concept was valid, but technique needed improving. A way was needed to be clear of a plane before a parachute was actuated. But World War One ended without a solution. However, lives of airmen were saved with even rudimentary parachute systems. On October 22, 1922, 27-year-old Lieutenant Harold R. Harris, Army Air service, entered aviation history as the first person to use a manually operated parachute to make an emergency jump from a powered aircraft.
In the peacetime years that followed World War One, "Lucky Lindy" was another nickname earned by six-foot-four Charles "Slim" Lindbergh, Jr. long before his famed, daring solo flight in May 1927 across the Atlantic Ocean in the "Spirit of St. Louis." In the two and a half years before then, in emergency situations, he parachuted to safety four times, once as an army student pilot, again as a test pilot, and twice as a contract pilot for the U.S. Air Mail service.
Parachutes were given attention by American, British, French, Italian, and German civilian and military organizations, primarily as a life-saving device. It was decades later before parachutes were developed for delivery of military battle personnel and supplies.
Brooks Field was home to an innovative paratrooper experiment in April and September of 1929. Interested in the additional possibilities of flight, Master Sergeant Erwin H. Nickles and Alfonso A. Orozco developed the first experiments in paratrooper warfare by inventing specialized parachutes and padded containers for arms and ammunition. Their experiments involved men with parachutes strapped to their backs who lay prone on the wings of the aircraft as they became airborne. On a given signal, the men leapt from the wings and shortly after released their parachutes. In September 1929, an experiment witnessed by a large audience, including foreign dignitaries, demonstrated that a large group of men could land together at Brooks Field and set up Lewis machine guns in four minutes. These early experiments demonstrated the possibilities aircraft afforded military planners.
Both parachutists and supplies were dropped at disaster scenes in the US during the 1920s and 1930s. In the mid-1930s, the Russians pioneered large-scale airborne and air-supply operations, while the Italian army used airdrop procedures in its campaign against the Ethiopians.
The development of modern parachutes deployed at high speeds and high altitudes started in the 1930's. Knacke and Madelung developed the ribbon parachute in Germany for decelerating heavy high speed payloads. In 1933 the Germans investigated the feasibility of developing parachutes suitable for in-flight and landing deceleration of aircraft. As a result of these investigations, the ribbon parachute was developed and successfully tested in 1937 as a landing brake for a Junker's W-34 aircraft. The ribbon parachute was adequately stable, opened reliably, had a low opening shock, and did not interfere with the controllability of the aircraft. The Germans, during World War II, used ribbon parachutes as landing deceleration parachutes and retractable dive brakes.
The Germans used mass airborne troops to support the invasion of Holland, Belgium and Luxembourg and dropped upwards of 35,000 airborne troops on the isle of Crete. After World War II Knacke invented the ring slot parachute which was used for moderate subsonic speeds. This parachute was used primarily for cargo delivery and aircraft deceleration. The ring slot parachute is significantly cheaper to manufacture than the ribbon parachute. The ring sail parachute, developed by Ewing, was used to decelerate payloads at low to moderate subsonic deployments speeds [the ring sail parachute was used as the final stages of the Mercury, Gemini, and Apollo projects because of its slow inflation rate and stability].
Aerial delivery and cargo parachutes were gradually evolved from personnel parachutes to perform the specific job for which they have been designed. By the end of World War II, five sizes and weights of parachutes were in use. The aerial delivery parachute, known as type G-1, is a 24' canopy for use with loads up to 300 pounds. It was standardized in December of 1942. The parachutes, cargo, dropping, are known as types G-2, G-3, G-4, and G-5. Their canopies measure 24', 28', 36', and 48', respectively, and are capable of carrying loads up to 3,000 pounds. Parachute assemblies consist of the canopy and pack. Early models of the canopies were of cotton fabric, later changed to rayon. Some of the larger canopies were made of nylon because of its lightness and strength. For identification purposes, canopies were made in various colors-red, green, blue, yellow, or natural. By establishing a color code, the type of supplies being delivered is easily determined by the color of the canopy. For instance, blue canopies might designate water, red canopies, ammunition, green canopies, rations, etc.
Cargo parachutes, being larger and constructed of heavier material than the aerial-delivery parachutes, are dropped from higher altitudes, for, as the size or weight of the canopy increases, the greater is the opening time required. The Army Air Force Board considered 200 feet to be the best altitude for dropping supplies and equipment from aircraft by parachute, with variations depending upon the type of load. Dropping at such low altitudes eliminates drift and assures greater accuracy in landing supplies in the desired drop zone. It also eliminates oscillation of the load to a great extent.
The ringslot parachute was developed in 1951 at Wright Field as a low cost replacement of the ribbon parachute. The ringslot parachute is used today on several US and foreign fighter aircraft. Several foreign countries use the Cross parachute. The Cross parachute is employed in the US as a drag brake for automobile dragsters. A varied porosity version of the conical ribbon parachute type, using continuous ribbons, has been introduced as an aircraft drag parachute. The Cross and the varied porosity parachutes have the same drag as a ringslot parachute of equivalent size but have a slightly higher opening load factor. The Cross parachute is relatively inexpensive to manufacture.
The Korean War revealed many problems in delivering large amounts of war materiel to ground troops in combat zones. Thus, a major effort was to develop methods of safely delivering air cargo to ground units, either by means of conventional airdrops or, later, through ground-level parachute extraction techniques. First, the 6511th Test Group (Parachute) at El Centro CA completed the C-124 Globemaster II Aerial Delivery System test program in May 1953. Two years later it successfully airdropped A-22 cargo containers, an M-29C cargo truck, and a 105mm howitzer from a C-123B Provider using techniques that later would prove invaluable in Vietnam.
Parachute technology was primitive but effective. Soldiers felt extreme forces exiting the aircraft and hitting the ground at a rapid rate of descent. A reason for the initial shock was that the early T-5 parachute opened canopy first, unlike today's parachute that allows the cords to unravel to slow the acceleration.
The Rogallo wing was conceived in the late 1940s by Francis and Gertrude. He was an aeronautical engineer who worked at the Langley Research Center for the NACA (National Advisory Committee for Aeronautics, the predecessor agency of NASA). Rogallo created the flexible wing on his own and successfully flew a prototype in 1948. He patented the design in 1951, but the first real public exposure didn't come until 11 years later when NASA began evaluating the concept for the manned spaceflight program. NASA chose not to utilize the parawing to land Mercury, Gemini or Apollo spacecraft but the military was interested in its using Ragallo's wing for parachuting. In the mid-1960's, two parachute companies, Pioneer Aerospace and Irvin Industries, obtained a license from NASA and proceeded to manufacture parawings and later inflatable wings. In 1965, the Army's Golden Knight precision parachute team were the first to jump these parawings and demonstrate their unique steerability. The Rogallo wing made the sport of hang gliding one of the most widespread forms of flying throughout the world.
By the late 1970's the parawing was replaced by the parafoil ram-air parachutes, invented in the middle 1960's by Domina Jalbert, a kite maker. The parafoil or ram-air parachute, a technology first developed by the Army, is a deformable airfoil that maintains its profile by trapping air between two rectangularly shaped membranes, sewn together at the trailing edge and sides, but open at the leading edge.
A parafoil is a parachute-like device that can be steered, used especially in kites and paragliders. A parafoil is a fully soft inflatable wing, which are familiar in the sports of hang gliding and parachuting. This system is designed to retard the vertical velocity and provide a relatively soft touchdown. The lifting parafoil has three advantages over the conventional type: 1) being able to reduce the dispersions associated with trajectories by using its maneuverability to glide to a predetermined point, 2) having the capability of being manually controlled to minimize landing area impact dispersions and, 3) by flairing, to reduce the impact shock at touchdown. The advantages of a conventional parachute are reduced weight and less complexity. If a parafoil is deployed at an altitude of approximately 6000 meters, typical performance characteristics provide a maneuvering circle of about 16 km in radius.
The parafoil, or "square" parachute, is popular in sport parachuting but only sees limited use in the military, mainly among special operations units and demonstration teams. The majority of military parachutes are round in shape and have limited or no steering capability, which is important to large scale paratrooper operations. It is undesirable to have several hundred paratroopers independently steering their parachutes because of the risk of collision.
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