Factual error: When the archangels jump from the helicopter, the "bait" is looking behind him saying he can see the dragon. For a parajumper to look between his legs to view behind himself, he would de-arch and thus de-stabilise himself while travelling at that speed. It would send the jumper into a barrel-roll spin.
Factual error: At the end of the film, in the battle with the male dragon, what are American traffic lights doing in London?
Factual error: In the scene when they are traveling at night towards London, when they stop at the blockade of burnt out cars and observe the 'London 666' sign, you can partially see that the sign is meant to be a remaining sign for the A5 road in the UK. They are apparently meant to be in Pembury, which is below south London, whereas the A5 goes north of London. Also Pembury is around 30 miles away from London, not 66. (01:07:30)