Factual error: When the bad guys are looking through walls with the rail gun's scope the light on the gun shines through the wall, but in real life it doesn't do that unless you are looking through a window. (00:27:15)
Factual error: When the Feds are going to the log cabin, while they are outside, gearing up, Arnold casually attaches a silencer, and pulls back the slide of his pistol, but the slide stays in the rearward position, a condition which should only occur when an empty magazine is in the weapon. Arnold notices and tries to push it forward, this doesn't work so Arnold hides it with his hand for the remainder of the scene. (00:42:50)
Factual error: The bad guys are able to close in on Vanessa Williams at the end by tracing the signal Arnie sends to her beeper. How could they triangulate her location through a passive, receptive device? Maybe if it was a cell phone, but not a pager. (00:50:10)
Factual error: When Arnie shoots out the cockpit window, first of all the glass seems about as thick as a Coke bottle which in reality it isn't. Secondly it shatters like one, not like the modern safety glass which it would be made of. (00:56:20)
Factual error: After removing the first parachute, Arnold uses the emergency one. However, when he deploys it, he is only a few hundred feet off of the ground. At this height, the parachute would do nothing except possibly snap Arnold's spine. (00:57:10)
Factual error: When the glass shutters come down in the Cyrez building, both he and James Caans' character start shooting at the glass. Bullet proof or not, you would be able to see marks on the glass. (01:24:00)
Factual error: Vanessa Williams' character hits a bad guy with the coffee pot from the coffee machine and knocks him out. Unlikely, given that the glass is very thin and light on these pots, and there was virtually no coffee in the pot to give it any weight. (01:38:00)
Factual error: Even aside from the ridiculous recoil that a railgun would cause (yeah, I know they don't use gunpowder, but there's got to be SOME opposite movement, surely), how come when the darts (bullets, whatever) go straight through people, they still get thrown backwards? The passage straight through them means minimal energy being transferred to them, and as such they shouldn't be hurled backwards that much.
Factual error: In several scenes where someone is shot with an EM gun it nails them to the wall, but if someone was shot with a bullet that was going near the speed of light it would go right though them. And the person wouldn't move at all, they would just fall down.
Factual error: When they are running the disc from Donahue's office, the technician takes the radio to transmit their exact location. But at the beginning of the movie, they "lose transmission in the vault." There's no way a radio would work in that room.
Suggested correction: The video transmitter is low power (likely under 1 watt, and possibly also in the microwave frequencies) whereas the 2-way commercial radio is much higher power, in the UHF or VHF bands, with a system that is designed to minimize dead spots in the building, likely using a repeater system to boost the coverage.
Factual error: In the train wreck scene at the end of the film, we hear the railroad warning bell clanging, the train horn blaring, James Caan and friends screaming, the fiery roar of the impact, and the rumble of the train plowing through the wreckage. In reality, all of these sound effects would have been drowned out for the duration of the scene by the ear-splitting, squealing screech of powerful railroad brakes that the engineer would have applied long before an unavoidable impact. Omitting the sound of railroad brakes is still a common factual error in modern train-collision sequences.
Factual error: All the containers have sheet metal covering the bottom, not visible bottom crossbeams as they should.
