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History of Aviation




History of Aviation


1.   First trials

The earliest recorded use of power to make objects fly was during the classic Greek civilization. About 500 B.C. Heron of Alexandria harnessed steam power when he constructed a rotating boiler with four vertical vents. Some fifty years later Archytas of Tarentum used a steam jet to launch a wooden bird. But it was not until the onset of the Industrial Revolution in England at the beginning of the 18th century that the steam engine became mass-produced and less expensive.



Step by step, advances were made during the remainder of the 19th century. In 1857 a French naval officer, Felix du Temple, designed a powered aeroplane notable for a retractable landing gear and the recommendation of lightweight metal, aluminium. A model of du Temple's aircraft was tested in 1874. Launched down a hill and driven by a tractor propeller powered by steam, it was more of a 'hop' than a real flight, but some historians give du Temple credit for the first powered flight. A similar claim was made by Russia in 1949 for the design of Alexander Mozhaisky, whose three propeller steam-driven plane lifted slightly off the ground in 1884 before crashing. In 1890 a Frenchman, Clement Ader, became the first person in history to lift off the ground in a powered aircraft of his own design, but his invention could neither be controlled nor remain in the air. His falsified claims notwithstanding, further tests by Ader during the '90s were no more successful, as he made no improvements in power or control. Finally Hiram Maxim, already famous for his machine gun, developed an ingenious steam engine of 350 horsepower, which he hoped would lift his gargantuan (8,000 pound) aircraft. Proceeding with caution, Maxim strapped the machine down while he tested the engines, fearing they might explode and destroy the plane. They performed exceptionally well, building up so much power that they tore loose the strapping and the plane rose a few inches in the air, startling the test crew onboard. Although Maxim's engine was advanced, it did not contribute to aviation and he abandoned the design. Most of these experiments, with their focus on power alone, illustrated the remark made in the next century by Wilbur Wright: Given the proper power and inclined at the right angle, a barn door could be made to fly.

Orville and Wilbur Wright became interested in flight as boys in Ohio when their father gave them a rubber band powered toy glider, a recent invention of Alphonse Penaud. Although the brothers did not go onto higher education they were curious, creative and mechanically inclined. As adolescents they had designed and built their own printing press and published a weekly newspaper. When bicycling became popular in the 1890's they took advantage of the 'mania' and ran a successful bicycle repair shop. They made so much money repairing bikes they went on to design and manufacture their own bicycles and, of course, added mechanical innovations they had designed.

http://muttley.ucdavis.edu/Book/History/Images/336.jpgOne is tempted to imagine lazily that early one morning this pair of bicycle repairmen rode out to some sand dunes, doffed their hats, picked up hammer and nails, built and then flew the first real airplane in history. Nothing could be further from the truth. Their day of fame at Kitty Hawk in 1903 was the fourth year they had travelled there to test dozens of trail blazing innovations. In the preceding year they had made over 1000 successful gliding flights on those same dunes. In fact, the Wrights had taken a serious interest in aviation some years earlier when they began reading of Otto Lilienthal's gliding flights in Germany. Upon his death they vowed to continue his progress. Wilbur wrote to the Smithsonian Institution in Washington and requested a reading list. Among the books suggested was the recently published Progress in Flying Machines by Octave Chanute. Wilbur wrote to Chanute and a long and fruitful friendship was begun.

http://muttley.ucdavis.edu/Book/History/Images/538.jpgThe Wrights agreed with Chanute that intelligent control was mandatory for successful flight. To this end they committed themselves to read, test and revise as necessary all available data. In 1900 they made their first trip to Kill Devil Hills, near Kitty Hawk, North Carolina. The location was selected after an inquiry to the U.S. Weather Bureau indicated that the speed and steadiness of the winds there best suited their purpose. After a number of flights with a glider of their own design, they decided to change the curvature of the wings and increase the wing area. A good deal of experience was also gained in how to launch the glider and deal with the winds.

http://muttley.ucdavis.edu/Book/History/Images/542.jpgThe following year the Wrights met with significant failure at Kitty Hawk. The wing design proved to be faulty, not producing enough lift. They returned to Dayton, Ohio frustrated and confused. Re-evaluating data compiled by Lilienthal, they suspected that he made errors and determined to calculate their own tables. They studied wind tunnels constructed by Hiram Maxim and decided to construct a new one of their own (replacing the starch box which they had formerly used). The new wind tunnel was very helpful in the redesign of the wing. In it they tested over 200 airfoil shapes before perfecting one

http://muttley.ucdavis.edu/Book/History/Images/439.jpgIn September and October of 1902 they made nearly 1,000 successful flights at Kill Devil. Glider No. 3 was the prototype of all succeeding Wright aircraft configurations. Although avid admirers of Lilienthal, they had replaced his hang glider design and body control technique with their own original ideas. They had once observed a soaring buzzard right itself from a gust of wind by raising the wing tip of its lowered wing and regaining stability. They tested their idea on tethered kites and unmanned gliders before incorporating what they called 'wing warping' into their biplane, which had a forward elevator and a double fixed rudder. The rudder was wired into the wing warping control system. The pilot lay across the centre of the lower wing and around his hips a cradle was fastened. By twisting right or left to warp the wings he could control up and down movement. Warping a wing tip down, for example, caused an upward movement of the wing as air pressure struck the tip. The pilot operated the forward elevator with his hands by pulling or pushing rods, which would raise or lower the flight path. Through this technique the Wrights became the first aviators to execute stable turns. They had a mastery of control that exceeded anyone else. They were ready to add the final ingredient: power.



2.   First powered flights

http://muttley.ucdavis.edu/Book/History/Images/2125.jpgIn 1903 there were two other aviation pioneers who nearly beat the Wrights to fame. In Germany Karl Jatho made a number of hops and short flights of up to 200 feet between August and November, but his flights were not controlled or sustained and he grew discouraged and gave up. 'In spite of many efforts, cannot make longer or higher flights. Motor weak.'

The Wrights had spent the summer of 1903 building the Flyer, to be driven by a 12 horsepower engine of their design. It was crated and shipped from Dayton to Kitty Hawk in September, when the Wrights set up camp and began to assemble the Flyer. On December 14th the wind was right and a signal flag was raised to invite any interested members of the Coast Guard stationed at Kill Devil. The Wrights wanted witnesses in the event of success. A coin was tossed to see who would make the first attempt. Wilbur won and lay down on the wing to start the engine. The plane sputtered, dipped on one wing and crashed into the sand. Repairs were made and on December 17 the signal flag was raised again. Five men and a boy arrived to watch the new attempt. It was Orville's turn to fly.

The Flyer was in excellent shape so Wilbur made the second flight of the day. He flew 175 feet in 12 seconds. Orville improved upon that with 200 feet in 15 seconds. By noon Wilbur had flown again, this time travelling 852 feet in 59 seconds. The pitch control on the Flyer was overly sensitive, and the glider ended up in the sand. Flight was over for the day - but a new era of flight had just begun. Not that anyone took much notice. Perhaps it was Langley's public failure of the week before. Perhaps it was the new dirigible hoopla coming out of Europe. In any event no ticker tape parades heralded the Wrights' achievement. The hometown paper, the Dayton Journal, made no mention in the early editions and the later editions got the facts wrong. Incredibly it would be five years before the Wrights got their just due. During that time they were snubbed - twice - by the U.S. War Department and once by the British War Office. Finally in 1908 the War Department signed a contract for a Wright Flyer, provided it could meet certain tests. A month later a plan was instituted for the formation of a Wright company in France. Wilbur went to France to demonstrate the aircraft while Orville stayed at home to carry out the U.S. army tests.

The demonstrations by the Wrights in 1908 were really the first time the world came to know what had been accomplished five years earlier. And did they love it! Wilbur, in the words of the secretary of the Aeronautical Society in Britain, was 'in possession of a power which controls the fate of nations ' One of the French newspapers exclaimed that Wilbur's flights presented 'one of the most exciting spectacles ever presented in the history of applied science.' French aviator pioneers agreed with Rene Gasnier, who simply said, 'We are like children compared with the Wrights.' Orville was causing sensations of his own in the States, as he broke every known flying record including duration (an hour and fifteen minutes) and altitude (310 feet). By the end of the year Wilbur and Orville had accumulated over 36 hours of flight - more than six times that of all other pilots combined.

Fame has its price, and the Wright brothers would later be victimized by the attacks of jealous petty people. But for the moment they could savour their well-deserved recognition. And their accomplishment will forever be recorded in the history of aviation for they made flight a reality.




Since this moment the planes get faster.

3.   Jet Planes

The first recorded flight of a gas turbine engined aircraft, the Heinkel built He 178, took place on 27 August 1939. The aircraft was powered by Heinkel's first gas-turbine engine, the S.3. There is some historical confusion, however, concerning this first jet-powered flight. Much later, Ernst Heinkel recorded that his first engine (the S.3) was originally tested in an He 118, whilst others who worked on the engine have claimed that it was originally installed in an He 100 - a development of the rocket powered He 112. The He 118, designed as a dive-bomber, seems an unlikely choice of test bed for this engine since it would have had to be installed under the fuselage, but this account appears to generally be accepted. The He 100, however, was better suited for this purpose since it was already designed for jet (rocket) propulsion and could contain the engine in the fuselage.

The He 178 was the first ever purpose built turbojet powered aircraft. It had a large air intake in the nose, a long chromed steel jet pipe and featured a retractable tail wheel. When the aircraft was shown to the German Air Ministry, the officials were not very impressed and showed little interest in this new technology. Since Germany was now at war, they thought the Luftwaffe's resources should be concentrated on conventional aircraft.

This lack of interest and support, however, did not dissuade Heinkel and he continued with his research. He began the development of a new twin-engine jet fighter in 1939, which became the world's first jet-powered fighter aircraft to become airborne. The aircraft was given the designation He 280 and demonstrated many advanced features such as a pressurised cabin, high-set tail plane, tricycle undercarriage and even the world's first ejection seat.

The German Air Ministry gradually saw the potential of gas turbine powered aircraft and in early 1940 contracted Heinkel to produce a small number of test aircraft for fighter development. At this juncture, another airframe manufacturer, Messerschmitt AG, was given the same contract for a similar aircraft. Messerschmitt had been contracted two years previously to produce a twin-engine jet fighter design and now both the He 280 and the Messerschmitt aircraft were being developed further. The Messerschmitt project, known as project 1065, was later given the designation Me 262

It was not until 15 May 1941 that the first British turbojet powered aircraft flew. This was the Gloster E.28/39 experimental aircraft, which was powered by an original Power Jets W1 engine. This first flight was piloted by Gloster's chief test pilot, P. Sayer, and lasted for 17 minutes. The flight was very successful and 17 further uneventful test flights were made. While the British Air Ministry had not shown much enthusiasm earlier, it took a much greater interest in jet propulsion now that Great Britain was involved in a major war. Even before the E.28/39 had flown, the Air Ministry had placed contracts for new engines and a prototype twin-engine fighter designated F.9/40

Power Jets encountered many problems with the new engine, the W2, such as compressor surge and turbine blade failure. The Rover Company, which was going to produce the engine, was waiting for Power Jets to solve these problems so that it could start production. However, the resulting delay soon strained the relationship between Rover and Power Jets and, in a memorable moment of aviation history, Rolls-Royce offered to take over Rover's turbojet activities in exchange for it's tank engine factory. Rolls Royce was now in the turbojet industry. The F.9/40 prototype became the Gloster Meteor, the first British jet aircraft to enter operational service and the only Allied jet aircraft to serve in World War II. It first flew on March 5 1943 and entered service with the RAF's 616 squadron on 27 July 1944

4.    Experimental planes



Even though the velocity of new coming aircrafts was increasing, very soon it was realized that an invisible 'barrier' was preventing aircrafts from surpassing the speed of sound. This barrier was known as the famous 'sound barrier'. This barrier became the second biggest obstacle since man's first attempt at flying. The barrier took the life of several test pilots as they attempted to break the 'sound barrier' in the famous experimental aircraft, such as Bell X-1. Until in 1947, a young test pilot named Chuck Yeager exceeded the speed of sound. From that point on a series of experimental supersonic aircraft took to the sky breaking speed record after speed record. Until in 1962, the North American X-15 (Figure 6) rocket-powered experimental airplane achieved 6.7 times the speed of sound (Mach 6.7) at an altitude of 108 km.

On October 3 1967 the X-15A-2 research aircraft achieved a maximum Mach number of 6.72 piloted by Major Pete Knight. The events that led up to the flight really began five years earlier when, on its 31st flight, the number two X-15, S/N 66671, suffered major damage during an emergency landing at Mud Lake, Nevada.


Ten months prior to that emergency landing I had returned to Edwards as a civilian employee for AFFTC. Following my four years at Edwards in flight test engineering wearing the AF blue, I had accepted a job with NASA at Huntsville Alabama during which time I had worked on flight test of the Saturn rocket vehicle. Then near the end of 1961 I was contacted to see if I would be interested in returning to Edwards to work on the X-15. That was an easy yes. I had been missing airplanes so much that I would run out of the house to see the Southern Airways DC-3 fly over. So here I was back at Edwards working as the AFFTC flight planner on one of the most exciting programs of all times.

The ship 2 X-15 had entered the three-ship X-15 program in September 1959. In 1961 it had flown nine flights reaching a maximum Mach number of 6.04 and a max altitude of 217,000 feet.

5.   Supersonic Airplanes for public transport

 

In the late 60's two supersonic airplanes were built to carry 90-140 passengers with a speed of about Mach 2. The Tupolev Tu 144 (nickname: Concordski) took off on 31st December 1968 a few months before the maiden flight of the Concorde. This plane can carry at maximum 140 passengers but it had only 102 scheduled flights because of some technical problems. Today Tupolev is working on a new supersonic plane, which should take off until 2010.

Tupolev Tu 144

 
The Concorde was built by British Aerospace and Aerospaciale and had its maiden flight 1969. This plane can carry up to 95 passengers over a distance of about 7200km. Since the fatal crash near Paris where 113 people were killed, the Concorde was grounded and precisely checked. The British and French engineers made a lot of modifications so that this plane can take up its scheduled flights again.










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