A paper plane, paper airplane, paper glider, paper dart, or simply dart is a toy plane made out of paper or paperboard; the practice of constructing paper planes is sometimes referred to as aerogami (Japanese: kamihikōki), after origami, the Japanese art of paper folding. The origin of folded paper gliders is generally considered to be of Ancient China, though 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 aeroplane'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 omithooter 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 Clement 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 Kitty-Hawk 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 aeroplane 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, 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, style and fashion, over subsequent years.
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There are multiple goals for a flight:
- Distance (javelin throwing).
- Time (javelin throwing straight up with subsequent metamorphosis into a sailplane).
- Aerobatic (looping).
- Stable flight to understand flight mechanics of a good plane.
For every goal there is a typical plane and sometimes a world record.
There have been many attempts over the years to break the barriers of throwing a paper plane for the longest time aloft. Ken Blackburn held this Guinness World Record
for 13 years (1983–1996) and had regained the record on October 1998 by
keeping his paper plane aloft for 27.6 seconds (indoors). This was
confirmed by Guinness officials and a CNN report. The paper plane that Blackburn used in this record breaking attempt was a "glider".
Takuo Toda, who is an engineer and president of the Japan origami aeroplane association, set a new record for longest paper airplane flight at a competition in Hiroshima Prefecture in April 2009. His record flight topped Blackburn's by 0.3 seconds. He folded his plane, measuring approximately 10 cm in length, from a single sheet of paper, though his plane in this attempt included cellophane tape.
In December, 2009, Toda achieved a 27.1 second record for a plane (10 cm in length) made with nothing but one sheet of paper, no scissors or glue or tape. The record was set in a Japan Air Lines hangar at Tokyo's Haneda airport. Toda's goal is to break the 30-second mark.
The former Guinness world record holder Tim Richardson disagrees with the decision to put a 'tail' on the paper plane. His explanation of paper plane aerodynamics on his website mentions that the tail is not needed. He uses the real-life B-2 Spirit flying wing bomber as an example, stating that the weights along the wing should be put forward in order to stabilize the plane. (Note: paper airplanes do not need a tail primarily because they typically have a large, thin fuselage, which acts to prevent yaw, and wings along the entire length, which prevents pitch.)
Independently, Edmond Hui invented a Stealth Bomber-like paper airplane called the Paperang in 1977, based on hang glider aerodynamics. Uniquely, it has properly controlled airfoil sections, high aspect ratio wings, and a construction method designed to allow the builder to vary every aspect of its shape. It was the subject of a book, Amazing Paper Airplanes in 1987, and a number of newspaper articles in 1992. It is ineligible for most paper airplane competitions due to the use of a staple, but it has extremely high gliding performance exceeding glide ratios of 12 to 1 with good stability.
In 1975, origami artist Michael LaFosse designed a pure origami (one sheet; no cutting, glue or staples...) flying wing, which he named the "Art Deco Wing".
Though its aerodynamic form mimics some hang glider and supersonic airfoils, its invention evolved from exploring the beauty of folded pap
er first. Its glide ratio and stability are on a par with many of the best paper wing constructions that use glue, tape or staples. This design was first published in 1984 in the book "Wings and Things", by Stephen Weiss, St. Martin's Press.
Although it is a common view that light paper planes go farther than heavy ones, this is considered to be untrue by Blackburn. Blackburn's record-breaking 20-year-old paper plane was based on his belief that the best planes had short wings and are "heavy" at the point of the launch phase in which the thrower throws the paper plane into the air, and at the same time longer wings and a "lighter" weight would allow the paper plane to have better flight times but this cannot be thrown hard with much pressure into the air as a "heavy" weighted launch phase. According to Blackburn, "For maximum height and for a good transition to gliding flight, the throw must be within 10 degrees of vertical" — which shows that a speed of at least 60 miles per hour (about 100 kilometers per hour) is the amount needed to throw the paper plane successfully.
After the folding there are still gaps between different layers of folded paper (tearoff edge). These and the kinks transversal to the airflow may have a detrimental effect on aerodynamics, especially on the upper side of the wing. In some models the surfaces are not aligned to the direction of flow acting as airbrakes (notice the airbrakes of the B-2 in the picture above!). Typically the center of mass is at 1/4 and the center of area is at 1/2 of the plane lengths. Two methods exist to shift the center of mass to the front. One rolls up the leading edge which then stays unswept. The other uses a swept wing or axial folding to produce something like a fuselage extending out of leading edge of the wing.
