How To make a good paper airplane

I designed this a few years ago and this is my favorite plane. I call this the X-Plane because it is great for experimentation and learning aerodynamics. You can move more weight to the fuselage by varying where the central flap is located, speeding the plane up. You can play with the vertical tail sizes and configurations. You can even flip the main wing folds from the bottom to the top to see how this changes the lift. This design usually needs some flaps to balance it out properly. Enjoy