Factual error: Lt. Talbot is wearing a US Army (National Guard) uniform with his name tape saying "LT. TALBOT". Name tapes do not show rank. The rank is worn on the Battle Dress Uniform on a tab on the chest. (01:23:55)
Continuity mistake: The mayor suffers a bleeding head wound while evacuating City Hall. Several scenes later he is shown with no wound at all. Not even his hair is mussed. (00:40:30 - 00:46:30)
Other mistake: The remaining four people at the power plant are evacuating ahead of the explosion of the bomb they set. They are running towards the helicopter to escape. The scene shows the helicopter with the rotors already turning. But there is no-one on board, much less a pilot to have started the helicopter. (01:21:10)
Factual error: Cat hot wires a modern car. Cars newer than around 2004 are largely impossible to hot-wire. Modern vehicles come with a chip in their key fobs which are required for the ignition to start at all - no amount of hot-wiring can bypass these. (00:43:00)
Factual error: Dr. Irwin is picking a lock. He only inserts a pick and not also a tension wrench. You need both to pick a lock. (00:20:30)
Factual error: Cat Rivers is flying the R44 helicopter from the left seat. The R44 is a single pilot helicopter fitted with dual controls. Two collective levers may be installed (the left is removable) but the cyclic control is not of a conventional nature. This comprises a central stick terminating in a pivoting T bar, which only allows one of the pilots at any one time to control the cyclic with the hand grip in the 'normal' position. The R44 is normally flown from the right seat; it is possible to fly from the left seat and instructors regularly do so. Students and low experience pilots would normally only fly from the right seat, and are discouraged from flying from the left seat when with friends. This is because of the unusual cyclic control configuration and, to some extent, the different instrument scan and visual references for hovering when flying. (00:14:40)
