In the scene sequence where Al kidnaps Woody, Buzz slides down the gutter drain. When he jumps onto the pipe his helmet is off. As he slides down his helmet is on. When he hits the ground his helmet is off again.

When Woody tries to escape from Al's apartment. He unscrews the A/C vent cover. After unscrewing it, he decides to stay and slams the cover shut. Immediately after slamming it shut, the screw is back in place.