Corrected entry: In the opening scene, the alien craft slowly flies over the Apollo 11 placard on the moon, and there are footprints in the soil. The spacecraft causes vibrations that disturbs the soil around the placard and the footprints. There is no sound in space (or on the moon), and the moon's atmosphere is almost a vacuum, so the soil should not have been disturbed in such an extreme manner. This is deliberately done for the dramatic effect.
Corrected entry: When David is outside of the White House and he calls Conny, she walks over to the window with her phone by her right ear, then she swaps it to her left when she's looking out the window, but in a shot of her looking out the window, it is back by her right ear. (00:40:40)
Corrected entry: In the White House they mention "an AWAC. The aircraft [E-3 Sentry] is known as an AWACS [Airborne Warning and Control System], it is not plural so you don't drop the S. (00:16:45)
Corrected entry: While Steve and David are trying to escape the mother ship, they are approaching the ship's outer doors that are about to close. David keeps saying, "Must go faster, must go faster", then it shows Steve with his arms extended as if he is pushing the controls forward trying to make the craft go faster. The problem with this is that when they first tried to take off from Area 51, the controls were such that pulling back on them made the craft go forward, and pushing them forward made it go in reverse. But Steve was not pulling the controls back toward him when they were escaping.
Corrected entry: Will Smith's mustache is out of limits for military standards. The standard is that a mustache shall not extend lower than the top of the upper lip or past a vertical line drawn upward from the corner of the mouth. He's good on the first part, but out of regs on the second. (00:21:00)
Corrected entry: When the aliens are coming in to New York, there is a shot of people starting to run in the other direction, from where the ship is coming in. The cop on horseback turns the horse around to flee, and in the next shot from the side of the street, the cop turns his horse around again.
Corrected entry: Why do they attack the ships only with F/A-18s? They could fire a lot more warheads from submarines, destroyers and so on. (00:58:55)
Corrected entry: Will Smith's girlfriend avoids an explosion by ducking into a janitor's closet inside a tunnel, yet the special effects show the beam knocking over buildings, and there's even a shot of the entire city being levelled. The next day, however, there's all sorts of debris and survivors left behind. (00:47:55 - 01:06:15)
Corrected entry: When the President arrives at Area 51 he orders the guard to open the "clean room" where workers are wearing full body clean suits. Yet a few minutes later when Brent Spiner and his crew arrive (from within the clean room) they are all wearing street clothes and lab coats, not clean suits.
Corrected entry: Area 51 should be deep underground. The rocks should therefore provide everybody with enough cover for large bombs and even protection from the alien's primary weapon. When Will Smith and Jeff Goldblum go out to save the world in the alien spacecraft, the door to the surface opens. The launch site has its own door to the outside world. Why is it that the base is deep underground but has a big door leading to the surface that has no protection at all?
Corrected entry: That alien suit is rather odd: it needs to be cut open with a razor sharp knife, then the alien is covered in a fleshy mass, however the suit is so weak an alien gets knocked out when it gets punched.
Corrected entry: When the president talks to his wife who's in LA, he says he has a helicopter waiting to take her to Dulles airport, which is in Virginia. Then the General maybe 30 mins in the air after the attack says the helicopter never made it to Dulles. That's 2,444 miles - an average helicopter (which she gets in) can only go 250 miles before refuelling, they would have to refuel almost 10 times.
Corrected entry: As LA is destroyed, you see Jasmine sitting in her car. As she turns around in her seat to see the fire ball coming at her, you see the entrance to the tunnel is an arch. As she runs through the tunnel, the ground is level. But the morning after, she has to climb up to get back out of the tunnel entrance, which is now a complete circle. It looks as if she's coming out of a large drain pipe. (00:48:55 - 00:52:30)
Corrected entry: Early in the film, after the arrival of the alien spacecraft, President Whitmore indicates that, "We may need to upgrade to Defcon 3" in light of the worsening situation. The Defcon scale is lowered in response to a more threatening situation, and would therefore require a "downgrade to Defcon 3."
Corrected entry: When David and Steven break the Earth's atmosphere, there is no sign of the mother ship despite heading straight towards it in the next shot. (01:57:30)
Corrected entry: In the scene where Jimmy and Steve are being chased by 2 alien spacecraft, Jimmy says he is going to "try something", after which he makes a drastic high speed left turn away from Steve's plane. The G forces are so great, Jimmy can't breathe so he takes off his oxygen mask. Steve immediately yells, "Put your mask back on!", but how would he have known he removed his mask if he had already banked away from him and he couldn't actually see him?
Corrected entry: In the scene where David shows everyone how he can penetrate the fortress, he specifically says the only way to disable the shields in all the ships is to detonate a bomb in the mothership (he says it quickly towards the end of his little speech so pay attention) - But the shields go down way before they detonate the bomb, the shields go down as soon as they upload the virus.