Plot hole: The "death" of the three astronauts and the requirement to then fake the whole scenario of the failed mission was obviously unplanned - it came about because of an unexpected computer glitch which reported that they had burned up on reentry, causing a mad scramble to cover up the fake mission and kill the astronauts. Obviously it was planned to have the astronauts "return" to Earth as heroes after their supposed trip to Mars, maintaining their deception (under threat if necessary) for the rest of their lives. One problem. Every scientist on earth would be champing at the bit to get their hands on a sample of Martian rock. Samples would be worth billions, worth far more than Moon rocks are worth today. How was NASA going to explain they didn't have any? They could not possibly fake the rocks - Martian soil and rocks would have a number of identifiable characteristics that a smart first year college student could identify. Using Martian meteorites collected from the Earth's surface won't work, either - prolonged exposure to the Earth's atmosphere would leave tell tale weathering and chemical changes that would be instantly detectable. NASA have painted themselves into a corner and that is not something they would have failed to realise well in advance.PEDAUNT
Factual error: After the plane is submerged, Jack Lemmon says, "... this plane is pressurized!" Jet aircraft are pressurized by bleeding air from the compressor sections of the engines into the cabin; in other words, the plane is only pressurized while the engines are running. Also, aircraft are only pressurized to a few psi above the outside air pressure at altitude, and never to more than the air pressure at sea level. The water pressure would be a great deal higher than the air pressure in the cabin, and since aircraft are not water tight, the water would quickly fill the aircraft. (If the aircraft was in 50 feet of water, the water pressure would be 21.7 psi, versus a maximum cabin pressure of 14.7 psi.)
Continuity mistake: When the crew hauls the female orca aboard the boat, the harpoon line is wrapped around her entire body several times. When they cut the rope and drop her into the water, the line is wrapped only around her tail. When the male orca is pushing her at sea, the rope is again wrapped around her entire body.wizard_of_gore
Factual error: Donald Pleasence's character makes a left turn at an intersection controlled by a traffic light. The camera pulls back and reveals an Interstate highway shield on the road he turned from. Interstate highways never have at-grade intersections controlled by traffic lights; they are designed to be non-stop routes with access to side roads available only through ramps and grade-separated interchanges.
Visible crew/equipment: When 'The Car' catches the truck, it tries to shove it off the road. The 3rd attempt happens as the Car gets very close to the camera, then veers across the screen, our left to right. The clear shadows of several crew members aboard the camera truck are visible on the front of the Car. (01:24:50)johnrosa
Continuity mistake: In the opening scenes, when David is chiding Gail for grabbing him through the porthole of the wreck, his right hand is gloved, then ungloved, then regloved..all in the space of a few moments.
Deliberate mistake: After the chopper drags the blimp about a mile out to sea, Kabakov unhooks it, and the blimp's bomb explodes seconds after. Why would he unhook it that close to shore with the dirigible's engines still pushing it back toward land and all those people? He had no idea when the bomb would go off. The bomb's fuse was set by hand inside the gondola.