Advanced paper gliders

Developments

Paper gliders have experienced three forms of development in the period 1930–1988:

    * High flight performance
    * Scale modeling
    * Use of CAD software

Ongoing development of folded/origami gliders over the same period has seen similar sophistication, including the addition of the following construction refinements

    * Increased fold-count, sometimes of an intricate nature
    * Explicit kirigami (cutting of paper) as a component of design
    * Requirements for additional ballast to ensure flight performance

Technological introductions

Technology responsible[citation needed] for the proliferation of advanced paper plane construction:

    * Inexpensive CAD software for 2D part design
    * Widespread manufacture, and inexpensive nature of acetal air-annealed glues, e.g. Bostick Clear-bond.
    * Inexpensive Ink-jet, and Laser-jet computer printers, for accurate aircraft part reproduction
    * The advent of the Internet, and widespread information sharing

Material considerations

Compared to balsa wood, another material commonly used to fabricate model planes, paper's density is higher; consequentially, conventional origami paper gliders (see above) suffer from higher drag, as well as imperfectly aerodynamic wing chords.

However, unlike balsa gliders, paper gliders have a far higher strength to thickness ratio – a sheet of office-quality 80 g/sq m photocopier/laser printer paper, for example, has approximate in-scale strength of aircraft-grade aluminium sheet metal, while card stock approximates the properties of steel at the scale of paper model aircraft.
Directions in advanced paper aircraft design

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 at low Reynolds numbers.
White Wings

In Japan in the late 1970s, Professor Yasuaki Ninomiya designed an advanced type of paper aircraft, which are sold as the 'White Wings' Series of paper glider packs.

White Wings are a stark departure from conventional paper aircraft, in that their fuselages and wings are paper templates cut and glued together. They were designed with the aid of low-speed aerodynamics. The early models were explicitly hand drawn, but by the 1980s these had their parts drafted with the use of CAD software.

Prof. Ninomiya's designs also included, for the first time in any paper model, working propellers driven by airflow, in particular for his profile scale models of the Cessna Skymaster and Piaggio P.136 of 1967. Noteworthy as well was the careful design of gliders so that they could fly without ballast – his F-4 Phantom II model is able to be flown immediately without recourse to paperclips etc.

The high performance gliders have fuselages that are kept rigid by the use of a balsa fuselage profile bonded to the paper components. The paper used is quite heavy, approximately twice the weight of standard drawing cartridge paper, but lighter than lightweight cardboard. Original White Wings were entirely paper, requiring patience and skill. Later however, balsa-wood fuselages were used, and White Wings were sold "pre-cut", making construction easier. The aerofoil used is a Göttingen 801 (curved plate), and a pattern is supplied as a cutout part of each kit.
Paper Pilot

Professor E.H. Mathews and the University of the Witwatersrand, in South Africa, developed a more mature form of the White Wings gliders for sale to South African children and teenagers in the 1980s. His gliders are designed using aerodynamic principles in the style of the White Wings series, they differ in construction, being of all-paper rather than paper-balsa laminate fuselage. The first book of gliders was entitled 'Paper Pilot', and was published by Struik in 1987. The Paper Pilot gliders are a watershed in paper model aircraft – they are the first commercial paper models to have been designed completely on a CAD system, and the first to be tested exhaustively in a wind tunnel.

The performance of the Paper Pilot gliders is almost equivalent to that of the Ninomiya gliders – but one of the first designs, a profile model of the SAAF C-160Z Transall, has a gliding distance of greater than the length of a rugby pitch.

The early gliders were designed to incorporate a catapult hook shaped from a paper clip. Later designs (and upgraded early designs) incorporated the addition of a bungee hook, permitting extremely long distance flights.

A remarkable characteristic of the Paper Pilot gliders is their ability to be flight trimmed – to the point of being able to fly straight in confined spaces, which few modern paper gliders can do.

E.H. Mathews designs then developed in 12 Planes for the Paper Pilot (Struik, 1994) into aircraft with three dimensional fuselages – models included the J-3 Piper Cub, Beech Stagger-Wing Biplane, Lockheed U-2 and Britten-Norman Trislander (a subject of a high performance flat glider earier in the series).

E.H. Mathews authored a commemorative model of the SAAF Junkers Ju-52/3m 'Johan van Riebeek' in 1999, and an as-yet unreleased model of the Airbus A-320 airliner in South African Airways colours, seen on the SABC youth TV program 'Tekkies' in 1998, as a prototype.

The most astonishing glider developed by Prof. Mathews was the Papercopter – a free-flight paper model helicopter, with a rotationally stabilised ring-wing as the flight dynamic element. Three variants were developed – the standard Papercopter of 1991, the Airwolf (1993) and the Stealth helicopter.
Paper helicopters (autogyros)

The world's first known published paper autogyro (engineless helicopter) by Richard K Neu appeared in "The Great International Paper Airplane Book" published in 1967. Its wings fly in a circle around a central ballast shaft as it descends vertically. This basic design has been published several times and is widely known.

The world's first known published forward gliding paper autogyro with forward pointing body lifted by spinning blades was built by James Zongker. It appears on page 53 of "The Paper Airplane Book: The Official Book of the Second Great International Paper Airplane Contest" published in 1985 by Science Magazine. Its twin contra-rotating blades automatically spin on paper axles upon launch to provide lift.

As noted above (see entry, Paper Pilot), E.H. Mathews developed a flight stable paper model helicopter. This has a ring wing, and flaps for adjusting for flight for stability, positioned on the inboard edge of the ring. While not an autogyro per sê, this paper model aircraft class falls within the general design of a paper model helicopter, and does possess a rotational flight element producing lift during forward flight. Papercopters, as Professor Mathews labeled them, are unique among paper model rotorcraft in having a range and velocity far in excess of all other classes, able to fly quite quickly, and with a range of between 10–15 m. The longest flight time is 27.6 seconds[citation needed].
World records
NASA launches the world's largest paper plane (at that time) – wingspan 30 ft, 6 in 1992.

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.[1]

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.[2] 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,[3] set a new record for longest paper plane flight at a competition in Hiroshima Prefecture in April 2009.[4] 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.[3]

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.[3]