Visible crew/equipment: In the Reactor Room scene, where the Marines first encounter the aliens, there's a part where Dietrich is grabbed from behind and accidentally ignites Frost with her flamethrower, causing him to fall down the stairwell. As he's falling, if you look, you can see part of a leg and a cable belonging to one of the technicians on the set. (01:14:05)
Visible crew/equipment: When Ripley is first shown in the loader after asking Apone if she can help, after the loaders claws grab the crate and she swings the crate around and asks "where you want it?" you can see tubes trailing off to the left of the loader that don't connect to anything in frame. The tubes are on the right side of the frame just under the crate in the loader's arms.