When Sam parachutes out of the plane, as he gets farther from the camera, his character model is briefly replaced with the robot's that parachuted out moments earlier.
Just prior to the airplane blocking Bugs Bunny's hole in the ground the left wing of the airplane shows 4 engines. Afterwards through out the cartoon the airplane shows only 3 engines on each wing.
The newspaper in the opening shot reads "Monday Feb. 2, 1951," but the date actually fell on Friday.