Revealing mistake: During the disco scene, Elaine is dancing with a fisherman who was just stabbed in the back. The fisherman has a knife sticking out of his back and you can clearly see the block that the knife is stuck in protruding from his shirt. There are holes from other takes too.
Visible crew/equipment: Striker is in the pilot's seat and a vulture is sitting on the back of it. On the bottom-left of screen you can see someone's forearm in a white sleeve, giving the suggestion that either Randy or Elaine are standing, and leaning on the pilot seat's armrest. However, Randy is not in the cockpit and Elaine is sitting in the co-pilot's seat.
Continuity mistake: After you see all the newspapers talking about the plane, and when you see the drummer on TV who speaks by drum tones, when the drums are handed to him the ends of the sticks are round, but when he looks to HIS left, after the camera changes position, they're not round anymore.
Revealing mistake: When Elaine is visiting Ted at the mental hospital and she says Lt. Zipp died this morning, when Ted picks up the water right before he spits, there's the same amount in the glass when he picked it up and set it down. So he didn't drink anything or spit any water.
Revealing mistake: In the flashback scene in the bar, one of the girl scouts slams the other girl scout onto the floor and one can see the mat that the girl lands on. It had been covered in dirt or dust but when the girl lands it is swept away and you can see one of the corners of the mat.
Revealing mistake: Throughout the cockpit scenes, Otto's (the auto pilot) face is just painted, with no facial features sticking out. When he is about to fly the plane, he winks out the window, and turns his head. After he turns his head you can see the extra attachment on his left eye used for this.
Continuity mistake: In one of the first establishing shots of the starring Boeing 707, the tailplane livery would suggest that the aircraft is a real-life Trans World Airlines (TWA) airliner with 'Trans American' and 'TA' merely painted on. However, in nearly all subsequent shots (such as that of the aircraft in the air), the tailplane design is noticeably different - the thick red square is now a thin red stripe instead. Also, a further red stripe now extends upwards over the fuselage just before the tailplane.
Continuity mistake: At the end when Elaine and Ted are standing on the runway kissing, the first shot of their plane can be seen in the background and it appears to be up off the runway on its landing gear, not lying flat on its belly. When Otto starts the engines to take off and the camera focuses back on the plane, the plane is back on it's belly like it was when it landed.
Continuity mistake: In the scenes on the plane, the camera angle showing the seats down the left side (on the plane's right side) change from 3 seats to 2 seats, then back again. This is evident because the 2 black passengers who speak 'Jive" are seen in their seats with both 3 and 2, and not because it goes from Coach to First Class.