the course of it he picked up a paper menu and fashioned a small model airplane, without thinking where he was. It landed on the shirtfront of the French Minister of Education, much to the embarrassment of my sister and others at the banquet. In 1930 Jack Northrop (co-founder of the Lockheed Corporation) used 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, style and fashion, over subsequent years. 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 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 and laser computer printers, for accurate aircraft part reproduction The advent of the Internet, and widespread information sharing Material considerations Compared to balsa material commonly used to fabricate model 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: 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