Why do some Paper Airplanes fly upside-down?

Question

Some of the paper airplanes I’ve tried folding always fly upside down. Why? They fly perfectly both ways

In: Engineering

Answer 1

Paper airplanes tend to fly too slow for ‘airplane aerodynamics’ to matter.

Instead, think of airplanes as a leaf with a handle. Add some weight on one side of the leaf, and the leaf will fall towards that side, which catches air underneath it, which floats the leaf up.

As long as the airplane type can catch air ‘underneath’ it right side up or upside down, this effect will work.