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History Of Airplanes Essay, Research Paper

THE HISTORY OF AIRPLANES, AND THEIR MODERN COMMERCIAL USE

Before the end of the 18th century, few people had applied themselves to the study of flight. One was Leonardo da Vinci, during the 15th century. Leonardo was preoccupied chiefly with the bird flight and with flapping-wing machines, called ornithopters. His aeronautical work lay unknown until late in the 19th century, when it could furnish little of technical value to experimenters but was a source of inspiration to aspiring engineers. Apart from Leonardo’s efforts, three devices important to aviation had been invented in Europe in the Middle Ages and had reached a high stage of development by Leonardo’s time: The windmill, an early propeller, the kite, an early airplane wing; (as well as the model helicopter). Between 1799 and 1809 the English baronet Sir George Cayley created the concept of the modern airplane. Through his published works, Cayley laid the foundations of aerodynamics. In 1853, in his third full-size machine, Cayley sent his unwilling coachmen on the first gliding flight in history.

The English inventor William Samuel Henson published his patented design for an Aerial Steam Carriage. Henson’s design did more than any other to establish the form of the modern airplane. Steam-powered models made by Henson in 1847 were promising but unsuccessful. German aeronautical engineer Otto Lilienthal and American inventor Samuel Pierpont Langley had been working for several years on flying machines. Between 1891 and 1896, Lilienthal made thousands of successful flights in hang gliders he designed. Lilienthal hung in a frame between the wings and controlled his gliders entirely by swinging his torso and legs in the direction in which he intended to go. While successful as gliders, his designs lacked a control system and a reliable method for powering the craft. He was killed in a gliding accident in 1896. Langley began experimenting in 1892 with a steam-powered, unmanned aircraft, and in 1896 made the first successful flight of any mechanically propelled heavier-than-air-craft . Launched by catapult from a houseboat on the Potomac River near Quantico, Virginia, the unmanned Aerodrome, as Langley called it, suffered from design faults. The Aerodrome never successfully carried a person, and thus prevented Langley from earning the place in history claimed by the Wright brothers. American aviators Orville and Wilbur Wright of Dayton, Ohio, are considered the fathers of the first successful heavier-than-air flying machine. Through the disciplines of sound scientific research and engineering, the Wright brothers put together the combination of critical characteristics that other designs of the day lacked which was a relatively lightweight, powerful engine; a reliable transmission and efficient propellers; and effective system for controlling the aircraft; and a wing and structure that was both strong and lightweight. At Kitty Hawk, North Carolina, on December 17, 1903, Orville Wright made the first successful flight of a manned, heavier-than-air, self-propelled craft called the Flyer. That first flight traveled a distance of about 37 m (120 feet). The distance was less than the wingspan of many modern airliners, but it represented the beginning of a new age in technology and human achievement. Their fourth and final flight lasted 59 seconds and covered only 260m. The third Flyer, which the Wrights constructed in 1905, was the world’s first fully practical airplane. It could bank, turn, circle, make figure eights, and remain in the air for as long as the fuel lasted, up to half and on occasions.

The airplane, like many other milestone inventions throughout history, was not immediately recognized for its potential. During the very early 1900s, prior to World War I, the airplane was relegated mostly to the county-fair circuit, where daredevil pilots drew large crowds, but few investors. One exception was the United States War Department, which as early as 1898 had expressed an interest in heavier-than-air craft. In 1908 the Wrights demonstrated their airplane to the U.S. Army’s Signal Corps at Fort Myer, Virginia. In September of that year, while circling the field at Fort Myer, Orville crashed while carrying an army observer, Lieutenant Thomas Selfridge. Selfridge died from his injuries and became the first fatality from the crash of a powered airplane.

During World War I, the development of the airplane accelerated dramatically. European designers such as the Dutch-American engineer Anthony Herman Fokker and the French engineer Louis Blerot exploited basic concepts created by the Wrights, and developed even faster, more capable, and deadlier combat airplanes. Biplane designs of Fokker, such as the D-VII and D-VIII flown by Germans pilots, were considered superior to their Allied competition. In 1915 Fokker mounted a machine gun with a timing gear so that the gun could fire between the rotating propellers. The resulting Fokker Eindecker monoplane fighter was, for a time, the most successful fighter in the skies. The biplane, with its double-decker wings, reached the peak of its development during the 1920s and 1930s, but was eventually overtaken by a design known as the monoplane.

The concentrated research and development made necessary by wartime pressures had resulted in great progress in airplane construction. Commercial aviation began in January of 1914, just 10 years after the Wrights first successful exhibition. The first regularly scheduled passenger line in the world operated between Saint Petersburg and Tampa, Florida. Commercial aviation developed slowly during the next 30 years. Airplanes technology was driven by the two world wars and service demands of the U.S. Post Office. It was not until after World War II (1939-1945), when comfortable, pressurized air transports became available in large numbers, that the airline industry really prospered. In the early 1920s the air-cooled engine was perfected. Light and powerful, these engines gave strong competition to the older, liquid-cooled engines. In the mid-1920s light airplanes were produced in great numbers, and club and private pleasure flying became popular. The inexpensive DeHavilland Moth biplane, introduced in 1925, put flying within the financial reach of many enthusiasts. The Moth could travel at 145 km/h, and was light, strong, and easy to handle.

On September 24, 1929, James Dolittle, an American pilot and army officer, proved the value of Sperry’s instruments by taking off, flying over a predetermined course, and landing, all without visual reference to then earth. Introduced in 1933, Boeing’s Model 247 was considered the first truly modern airliner. It was an all-metal, low-wing monoplane, with retractable landing gear, an insulted cabin, and room for 10 passengers. An order from United Air Lines for 60 planes of this type tied up Boeing’s production line and led indirectly to the development of the most successful propeller airliner in history, the Douglas DC-3.

When the United States entered World War II in 1941, there were fewer than 300 planes in airline service. Airplane production concentrated mainly on fighters and bombers, and reached a rate of nearly 50,000 a year by the end of the war. A large number of sophisticated new transports, used in wartime for troop and cargo carriage, became available to commercial operators after the war ended. Pressurized propeller planes such as the Douglas DC-6 and Lockhead Constellation, early versions of which carried troops and VIPs during the war, now carried paying passengers on transcontinental and transatlantic flights. Wartime technology efforts also brought to aviation such critical new developments the jet engines, which truly revolutionized commercial air transportation in the late 1950s. Jet transportation in the commercial-aviation arena arrived in 1952 with Britain’s DeHavilland Comet, an 885-km, four-engine jet. The Comet quickly suffered two fatal crashes due to structural problems and was grounded. This complication gave American manufacturers Boeing and Douglas time to bring the 707 and DC-8 to the market. Pan American World Airways inaugurated Boeing 707 jet service in October of 1958, and air travel changed dramatically almost overnight. Transatlantic jet service enabled travelers to fly from New York City to London, England, in less than eight hours, half the propeller-airplane time. Boeing’s new 707 carried 112 passengers at high speed and quickly brought an end to the propeller era for large commercial airplanes. Shorter-range jets then began to be produced at massive rates. Douglas delivered the DC-9, and Boeing produced both the 737 and the Trijet 727.

The next frontier, pioneered in the late 1960s, was the age of the jumbo jet. Boeing, McDonnell Douglas, and Lockheed all produced wide-body airliners, called jumbo jets . Boeing developed and still builds the 747. McDonnell Douglas built a somewhat smaller, three-engine jet called the MD-11. However, in 1995 Boeing introduced the 777, a wide body craft that can hold up to 400 passengers; which by far superceded any other jumbo jet in existence.

Airplane research continues today, in constant effort to make a bigger, faster, safer plane.


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