(at around 1h 21 mins) In the final chase scene, Nick and Kate both duck as Tony's boat approaches them. In the next shot, Nick and Kate are seen sitting upright while Tony's boat is making the jump.
(at around 36 mins) During the shark attack rescue scene, Tackleberry's gun is pointed at the shark's head sticking out of the water, the gun visibly above sea level. However, in the next shot, Tackleberry's gun and the shark are now underwater.
(at around 15 mins) Three goons traverse the gap between two buildings by shooting a grappling hook device, securing the line at their end first. You hear the word "Go!" telling the first to go, then "Go" for the second man, then "Go" for the third. You should only have heard the "Go" twice, as the last one wouldn't have told himself to go, and it was said by the same voice so no-one else could've told him to "Go". Plus when the second one was going across, from the camera angle looking back to the balcony they came from, no one was waiting for their turn. The camera angle switches again, well after the second guy left, and you see the third guy set off from the balcony.
(at around 24 mins) A jump-cut takes place immediately after Tony enters and closes the door of the airplane lavatory.
(at around 39 mins) Proctor's gloves disappear and reappear between shots when he is waterskiing.
Harris didn't need to break into the Commissioner's office to get Lassard's file. As Lassard is a police officer, thus a public employee, his personnel file is a public record. All Harris would have to do is ask for it.
The official movie poster depicts Michael Winslow with a moustache, despite him not having one in the film. This same goof was made in Police Academy 4: Citizens on Patrol (1987).
In the movie the officers have again moved up in rank (4 stripes on their sleeves), however four stripes is not a true rank in any United States Police Dept. Three stripes (sergeant) should be followed by Lieutenant (one silver bar on lapel) not four "upper" stripes.
(at around 18 mins) When they are walking into the airport to board the flight to Miami, we see them walk across a doormat that has "PBIA" on it. This is because this scene was filmed at Palm Beach International Airport. The fictional city where they live is someplace up north (Midwest, Northeast, or eastern Canada where it was filmed)
(at around 35 mins) When Hightower throws the Frisbee at Proctor, you can see the wire pulling Proctor up as he flies out of shot.
At around the 45 minute mark, one of the guys in the car spits milk out onto the windshield from the inside. However, the next scene shows them all getting out of the vehicle, and the windshield is clear.
Obvious smaller stunt double wearing padded clothing, when House falls from the helicopter through the roof of Mr. Dempsey's boat.
In the boat scene at the end, when the criminal's boat jumps over the other 2 boats and Nick tells Kate to "Duck!", there is clearly a mannequin used where Kate is supposed to be.
During her karate demonstration, Kate should be wearing a t-shirt under her gi to enure her modesty.
During her karate demonstration, Kate should be wearing a t-shirt under her gi to ensure her modesty.
(at around 1h 21 mins) When Commandant Lassard yells to his hostage taker, on the boat, "Well done!", the voice responds, "It's nothing!", but he is mouthing something else.
(at around 1h 22 mins) When Proctor, while hanging from the helicopter, knocks Lieutenant Harris off the boat, we hear Proctor call out, "I did that. I'm sorry, Sir...", but his mouth stopped moving after, "I did that."
(at around 1h 22 mins) When Harris gets knocked off the boat by Proctor, Harris can still be heard screaming, even after he is fully submerged in the water.
(at around 1h 26 mins) At the end, when Proctor kicks the chair to Harris, the rails under the chair are clearly visible.
(at around 46 mins) As the criminals are plotting to find the commandant you can see one of the henchman eating an actual powder donut in his left hand. When he moves back into his seat he reveals the prop donut in his right hand.