The citizens of Ottawa are ordered into shelters long before the lost missile passes over. Yet, just before the missile flies over, a bell rings and elementary school students in class duck under their desks. The scene is stock footage of a duck-and-cover drill but the kids should have been evacuated long before the missile appeared.
When the scientist's wife has her baby, a neighbor announces it's a very healthy boy but the baby is never heard crying at any time.
At 49:00, when David and Joan are in the car, the same stretch of houses and cars is repeated during the driving sequence.
Stock footage shows jets firing rockets at the Lost Missile as it passes in front of them. Since the speed of the missile is 4000 miles per hour, it would have shot by the jets and rockets within a second or two of the rockets' launches. In order to hit a missile going that fast, the jets would have had to fire before the target was in visual range.
With less than four minutes before Jove launches, the lead character secures the plutonium, drives the long distance to the missile base, gets to the launch pad, goes up to the Jove warhead on a slow-moving lift, places the plutonium inside, arms all the warhead mechanisms and gets back to ground and away from the Jove rocket, all in less than four minutes.
When American jets start their engines, the sound of propellers can be heard revving up, not jet engines.
The shots of purported Royal Canadian Air Force interceptor aircraft include British RAF Hawker Hunter and Gloster Meteor jets. Neither aircraft was used operationally by the RCAF.
When the panicked population in the subway jump onto the tracks to follow the last train, several of them touch the electrified third rail, including one man who runs along it, looks down and jumps off. None of them are electrocuted, save for a woman who falls down and grabs the rail with both hands. She would have been electrocuted before she could get her second hand onto the rail.
Even though authorities order the streets cleared except for emergency vehicles and school buses evacuating children, a man in a sports car almost wrecks the Jove project with an accident. Yet, after the jeep with the plutonium is carjacked, a solo driver in a sports car comes ambling along, down the road leading to the missile base without any explanation for why he's on the road.
The scientist's pregnant wife can't make it to the hospital and is taken to a neighbor's basement. No one can get hold of her husband and they don't know where he can be. Yet, later, before the missile reaches New York, the scientist is shown with his wife and newborn child, with no explanation for how he knew where she was and how he got to her so fast, since his base is far from the city.
With the fate of the world hanging in the balance and only minutes left they give him two jeeps instead of a helicopter and armed support.