In general, there are four aerodynamic forces that act on the paper aircraft while it is in flight: Engineer's record-breaking hopes sail on paper wings – October 8, 1998". CNN. 1998-10-08 . Retrieved 2009-06-22. Innovations include functional wheeled undercarriage which does not contribute to the drag budget while permitting good landings. Stability means the plane, if disturbed, will return to its original state. For pitch stability it means the plane will seek a single airspeed. A plane which is unstable in pitch will either pitch up into a stall, or nose dive, but won't settle out anywhere in between. A stable airplane will tend to oscillate up and down a few times, but converge on a steady flight speed. Many typical paper airplane designs are stable, but just barely. As a plane becomes more and more stable, it wants to fly faster and faster. To counter this tendency, up elevator must be used to produce a good trim airspeed. This is why many of the classic paper airplane designs are nearly neutrally stable. Few people realize good pitch stability requires a heavy nose and some up elevator. The classic designs rely on the small inherent "up elevator" effect (positive zero lift pitching moment) resulting from the swept wing, and possibly the airfoil shape. Thus many classic paper airplanes can be flown with no elevator adjustment. Sometimes they fly well, many times they don't, and they always have poor 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 paper 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.

Similar content to 1st book, concerning why paper airplanes fly, more hands-on experiments to demonstrate principles. Also a teachers guide for this book is available from the publisher with more paper airplane information]

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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.

Owen, Thomas (September 23, 1988). "LIGHT FLIGHT". The Christian Science Monitor. ISSN 0882-7729. ProQuest 1034592633. 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. Typically the center of mass is at 1/81 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. There are few technical references for paper airplanes. Naturally paper airplane books talk about paper airplane aerodynamics, but usually in a simplistic manner. There are many reference to low speed flight which are applicable to paper airplanes. Here are a few. I have also tried a version of the world record plane which does not have a fuselage, it is a flying wing with no dihedral, but uses the wingtips canted up and out at an angle for the dihedral effect. The idea is to eliminate the "V" shape of the fuselage and use that part of the paper to maximize the wing span to reduce the sink rate. Unfortunately I have not been able to achieve good ascents, with low launch heights as a result. This modification noticeably affects the flexibility which allows good launches.

4. The New World Champion Paper Airplane Book

Fold the top corners in so they meet at the middle. There should be a small triangle tail hanging out beneath these folds.