by Paul Doherty
Illustrations by Stephanie Syjuco

he most amazing thing about a paper airplane is that all you need to make one is a sheet of paper—nothing more. You don't need scissors, glue, tape, or paper clips. A few folds, a couple of adjustments, and you have a superb paper flyer. The properties of paper give the airplane all the attributes it needs.

If you've ever made a paper airplane, you've probably just folded the paper into a simple dart—as people have done for at least a hundred years. But in the last two decades, paper airplane designers have imported techniques from origami. Perhaps the best innovation was the addition of one fold to the classic dart design to create a plane called the "Nakamura lock" after the origami artist who designed it.
 

Once you've made all of your folds and the plane looks symmetrical, it's time to trim it, or adjust it, for flight. Give it a gentle toss forward. Your goal is to have it glide smoothly and gently to the ground, either flying straight or in a gradual curve.

Make these adjustments, if necessary:

• If the nose drops and the plane dives into the ground, bend up the back of the wings. A little bend goes a long way.
• If the nose rises first and then drops, the plane is stalling. Bend down the back of the wing. Keep your adjustments small.

When you get the plane to balance on the air and float down gently, then you can give it faster tosses.

Now that you have a flying plane, you can use it to see the roles that paper plays in its construction. After the kinetic energy (that is, the energy you put into it by throwing it) of the initial throw has dissipated, paper planes are gliders powered by gravity. As the plane falls, its wings deflect air backward and down, providing thrust and lift. Paper makes a good wing because it's impermeable to air: In a single sheet of paper, multiple layers of interlocked fibers prevent air from flowing through. In contrast, a hole-filled screen from a back door would not make a very good wing.