Air Plane Photos 2013: Paper Airplanes

Paper Airplanes Biography

Source(www.google.com.pk)

A paper plane, paper aeroplane (UK), paper airplane (US), paper glider, paper dart or dart is a toy aircraft, usually a glider made out of paper or paperboard; the practice of constructing paper planes is sometimes referred to as aerogami[citation needed] (Japanese: kamihikōki), after origami, the Japanese art of paper folding.

The origin of folded paper gliders is generally considered to be of Ancient China, although there is equal evidence that the refinement and development of folded gliders took place in equal measure in Japan. Certainly, manufacture of paper on a widespread scale took place in China 500 BCE, and origami and paper folding became popular within a century of this period, approximately 460-390 BCE. It is impossible to ascertain where and in what form the first paper aircraft were constructed, or even the first paper plane's form.

For over a thousand years after this, paper aircraft were the dominant man-made heavier-than-air craft whose principles could be readily appreciated, though thanks to their high drag coefficients, not of an exceptional performance when gliding over long distances. The pioneers of powered flight have all studied paper model aircraft in order to design larger machines. Da Vinci wrote of the building of a model plane out of parchment, and of testing some of his early ornithopter, an aircraft that flies by flapping wings,and parachute designs using paper models. Thereafter, Sir George Cayley explored the performance of paper gliders in the late 19th century. Other pioneers, such as Clément Ader, Prof. Charles Langley, and Alberto Santos-Dumont often tested ideas with paper as well as balsa models to confirm (in scale) their theories before putting them into practice.

The most significant use of paper models in aircraft designs were by the Wright brothers between 1899 and 1903, the date of the first powered flight from Kill Devil Hills, by the Wright Flyer. The Wrights used a wind tunnel to gain knowledge of the forces which could be used to control an aircraft in flight. They built numerous paper models, and tested them within their wind tunnel. By observing the forces produced by flexing the heavy paper models within the wind tunnel, the Wrights determined that control through flight surfaces by warping would be most effective, and in action identical to the later hinged aileron and elevator surfaces used today. Their paper models were very important in the process of moving on to progressively larger models, kites, gliders and ultimately on to the powered Flyer (in conjunction with the development of lightweight petrol engines). In this way, the paper model plane remains a very important key in the graduation from model to manned heavier-than-air flight.

With time, many other designers have improved and developed the paper model, while using it as a fundamentally useful tool in aircraft design. One of the earliest known applied (as in compound structures and many other aerodynamic refinements) modern paper plane was in 1909[citation needed], followed in 1930 by Jack Northrop's (co-founder of Lockheed Corporation) use of paper planes as test models for larger aircraft. In Germany, during the Great Depression, designers at Heinkel and Junkers used paper models in order to establish basic performance and structural forms in important projects, such as the Heinkel 111 and Junkers 88 tactical bomber programmes.

In recent times, paper model aircraft have gained great sophistication, and very high flight performance far removed from their origami origins, yet even origami aircraft have gained many new and exciting designs over the years, and gained much in terms of flight performance.

There have been many design improvements, including velocity, lift, propulsion,[1] style and fashion, over subsequent years.

Unmodified origami paper aircraft have very poor glide ratios, often not better than 7.5:1 depending on construction and materials. Modification of origami paper gliders can lead to marked improvements in flight performance, at the cost of weight and often with the inclusion of aerodynamic and/or structural compromises. Often, increases in wing loading can encourage breakdown of laminar flow over a wing with a hybrid of origami and glued and taped construction.

Professors Ninomiya and Mathews (see sections below) developed more directed design strategies in the late 1960s and the 1980s. Previously, paper model aircraft had been designed without an emphasis on performance in flight. By using aerodynamic design, and fluid dynamics, both professors were able to design models that exceeded previous flight performance criteria by a very wide margin. Ranges of flight increased from the typical 10+ meters to 85+ meters, depending on energy input into the gliders on launch.

At present, the work of the two professors remains the last serious research work on improving the flight performance of paper model gliders. Collaborative work by enthusiasts through online forums and personal websites are mostly developments of these original glider types.

In the field of scale model design, there are at present many possibilities for advanced design. Profile gliders encounter a limitation for improvement of flight performance based on their wing types, which are typically curved-plate aerofoils. In addition, fuselages are either balsa-paper or paper laminates, prone to warping or breakage over a very short time. Improvement in performance is possible through modelling three-dimensional fuselages which encourage laminar flow, and in internally braced wings which can then have high-lift aerofoil profiles, such as the Clark Y or NACA 4 or 6 series, for high lift .