So here’s a scene that we didn’t see in Superman: The Movie, straight from the shooting script:
The eagle bursts through a white cloud bank up once more into the clean blue air. After a short moment SUPERMAN does likewise, trailing the bird.
For a few moments we are privileged to witness this real beauty and poetry of flying as the eagle and SUPERMAN chase each other through the air doing banks, loops, and dives, swooping closely together like two beautiful fighter planes in tight formation.
The unspoken ceremony over, they silently acknowledge each other, then head off in different directions.
Obviously, that scene didn’t happen, because who has the time to choreograph eagles, but the interesting thing is that it made the cut all the way up to the shooting script. That says to me that they really didn’t know how hard it was going to be just getting Superman to fly in a credible way, without having to do a fucking raptor ballet on top of it.