Revealing mistake: During the night surfing scene notice that the sun is evident in the background (look closely it does not appear long). There are also shots where you can see clouds and faint blue sky. Moments later you see Keanu and Lori sitting in the water with completely different lighting which was actually taken at night and further distinguishes that the surfing shots were not actually done at night time. I heard the scene was shot during the day with a filter so it looked like it was shot at night.
Continuity mistake: During the scene where Utah is chasing the ex-president, we see Ronald Reagan run out of a house and scale a fence into a neighbours garden, instead of running down the driveway. The next shot then shows Utah running out of the house with the fence coming into view, but without seeing the ex-president, and then give chase over the fence. He wouldn't have known to jump over the fence, because he wouldn't have seen him go over it.
Continuity mistake: In the stakeout at Latigo Beach, Pappas is surveying Utah's surfing activities from a parked car with binoculars. Pappas takes off his sunglasses and puts them on the dashboard. Watch the sunglasses change position from upside down to right side up for no reason and in a matter of seconds between shots of Pappas watching Utah surf and then especially when Pappas and Utah are communicating on the radio.
Continuity mistake: In the night surfing scene, as Johnny gets up for the first wave, he is riding regular (left foot forward), but as the camera cuts back and forth he jumps back and forth between this stance and goofy (right foot forward). All other surfing shots of Johnny in the movie show him surfing goofy.
Factual error: In the second skydiving scene Patrick Swayze tells the pilot to fly the plane at 4000 feet, which he does as this can been seen on an altimeter. When skydiving from 4000 feet it would take 25 seconds before you hit the ground but the skydive in this scene lasts 1 minute 51 seconds.
Factual error: There is no way Utah could have gotten information about Tyler's parents' death, let alone the city and year, from the computer he was using at the FBI office. He would have had to run a separate search for that information using other sources. That type of personal information is not contained in any crime information database.
Other mistake: In the fight scene where Bohdi helps special agent Utah you see that his surf board gets broken in two and then after the fight he is seen leaving without the board, but in the scene where he and Tyler are woken up early to go surf right before Tyler says "you look like you just saw a ghost" you see him carrying the same board.
Deliberate mistake: When everyone is surfing at night, the sound of the waves in the background is significant, as it should be. However, at one point, when Keanu and Lori are having an intimate conversation on the water, the sound of the waves disappear. The wave sounds resume in the next scene.
Factual error: Australian police are never equipped like they are at the end of this movie. The 1st Police on the scene would be Constables, Senior Constables, Sergeants, & Senior Sergeants, & possibly plain-clothes Detectives from the Victorian Police Force. They'd be wearing their regulation uniform & carrying a regulation revolver & hand cuffs. The AFP *may* be liaising, but they're Detectives, too. No high-power weapons; no helicopters.