Continuity mistake: During the film's climax, in which the Wolf's wife Serena is on the run, CIA agent Peter Brandt tries to ambush her in an elevator. As he runs up to the elevator, we get a wide shot of him, the people waiting for the elevator, and the up/down indicator lights of the elevator. The down indicator is lit. (The shot pans down from the indicator lights as he runs up.) Cut to Elias briefly, then back to the elevator indicators. This time, neither light is on.
Other mistake: When Arnold throws The Wolf's wife into the electrical gate equipment and she is killed, they begin to fight. The Wolf beats Arnold repeatedly then takes out his Motorola cell phone to place a call to set off another bomb. When he pulls the phone from his pocket there is no signal (indicated by red light on phone). A few minutes later Arnold leans over, picks up the phone, and sees that all The Wolf had to do was press the phone button to send the call. So, do you suppose he saw that there were no signal bars on the display, like we did?
Visible crew/equipment: In the scene of the funeral for Arnold's wife and son, we hear the sounds of "Amazing Grace" being played on the bagpipes. There is a bagpiper in the distance, as the hymn goes on the piper can be seen blowing up his pipes and setting them under his arm without missing a note, which is physically impossible. When the camera pans to the gravesite, there is a second bagpiper in the foreground. He does the same exact thing, he blows up his pipes and sets them under his arm mid-tune with out missing a beat. When playing the bagpipes, you must fill the bag up with a certain amount of air to make the drones (the three pipes that come out of the bag and rest on the piper's shoulder) sound. You must then blow more air into the pipes to sound the chanter and play a tune. You cannot do what the bagpipers in this movie were doing and still play the tune.
Other mistake: When Gordie is running after the terrorists on the motorcycle he shuts down the gates, not allowing them to leave. It shows all of the gates closing and the terrorists going under a closing one. How could the terrorists get back to Gordie if all of the gates are closed and he doesn't open them?
Factual error: After the terrorists on the motorcycle take off, Gordon uses a fire axe to puncture the natural gas line. The natural gas (which was under pressure) would have quickly filled the tunnel. Now when the motorbike drives through it, the engine should have revved high with a combustible gas being taken in in place of oxygen. It would be like using nitrous on a hot rod. But you can hear the RPM's stay normal for a motorcycle.