I knew hundreds of people who took LSD in the 60s and none thought they could fly... That piece of misinformation came from Art Linkletter's mythology about how his daughter took LSD and then jumped out a window.

It also comes from CIA disinformation about the MK-ULTRA program. They disseminated a story that one of their experimental subjects jumped out of a window as a result of taking LSD. In fact his handlers beat him to death and threw him out of it because he was about to do a Bradley Manning.