From Scientific American
Three simple designs are here, guaranteed to be “the best paper airplanes on the planet.” We cannot certify that, but the ones we made flew splendidly. The authors are proud of record indoor flights of between 60 and 80 feet, hand-launched. This small guide is as close to physics as to technology, for it suggests the principles of good results–although it also includes precise instructions for the folding. You have to trim a paper airplane; if not, it will fly like a rock. “This is not an opinion. It is a guarantee,” and grade-school builders are not excepted. Symmetry is the aim, carefully secured. “The left side MUST look just like the right.” Here is how to check on that and how to adjust, with five troubleshooting hints, plus launch instructions for indoors and out. Take care. (Outdoors you might hit a thermal, and your plane can really go out of sight.)
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