edges – 45% improvement in Cd. Profile Performance: Göttingen curved-plate, with profile similar to Göttingen 801. Scale Performance: Göttingen 801 or any other wing aerofoil Scale Models: This varies on model type (see below) Camber of profiles varies, too. In general, the lower the Re, the greater the camber. Origami types will have 'ludicrous' or very high cambers in comparison with more marginally performing scale types, whose escalating masses demand higher flying speeds and so lower induced drag from high camber, though this will vary depending on type being modelled. In the case of scale performance and scale models, the modellers intent will define the type of aerofoil section chosen. WWI biplanes, if designed for flight performance, will often have curved-plate aerofoils, as these produce a highly cambered surfaces and Coefficient of Lift (Cl) for low gliding airspeeds. WWII monoplanes will often have very scale-like sections, though with increased trailing edge droop to improve camber in comparison with scale counterparts. Similarly, size, airspeed and mass will have very big impacts on choice of aerofoil, though this is a universal consideration in model plane design, no matter the material. Origami Flying Wings 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 planes 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 plane 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 plane 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...)