I think many of us have seen this magic before. As usual, watch the performance first.
I have tried to search how David Copperfield can fly in front of the audiance and yet they did not notice any tricks hidden. What I can guess is, definitely he uses some kind of invisible strings or ropes, and there should have some kind of mechanical structure that can hang him up and down, and move him forward and backward. I guess the structure would be quite expensive to build. His posture is very perfect that makes people feel that he is as if really flying. Of course, he has done a lot of practices before performing it on the stage.
I got a few sources with different explanation. I think this source makes more sense and fits with what I am thinking of. I would like to share here. Do comment if any. :)
Cheers,
Dennis Yew
