Deliberate mistake: The way the helicopter fell into the stadium at the end is impossible. Since the dead guy still held the control stick back, the rotor blades would still be pointed backwards making the helicopter fall even more back. Since there wasn't any controlled steering, it would spin around wildly. Not even a stunt pilot could maneuver a helicopter like that not to mention a dead body.
Sudden Death (1995)
1 deliberate mistake
Directed by: Peter Hyams
Starring: Jean-Claude Van Damme, Powers Boothe, Raymond J. Barry, Whittni Wright
Plot hole: When the game goes into Sudden Death, the teams are seen taking a brief timeout at the benches. The only problem here is: during the Stanley Cup playoffs, whenever a game heads into OT, the ice has to be resurfaced and both teams are sent to the dressing room. If this had happened, the Penguins would certainly have noticed that their dressing room was bullet-riddled from the fight that occurred earlier and would have - at the very least - figured something was up.
Hallmark: Have you had any contact with the aggressors?
Darren McCord: I killed two. Is that contact?
Trivia: One of the bad guys is playing the video game "Doom", which was released two years prior to the film for MS-DOS.