More can be written, but you might like to see some links provided in a previous summary reply by /u/Elm11 :

• "Did paper airplanes exist before the Wright Brothers?" , responses by /u/cthulhushrugged and others in the tree
• "Did people make paper airplanes before the airplane was invented?" , answers by /u/ashkenazeeyankee

Posting links to previous answers is not intended to discourage questions or further discussion.