Factual error: At the end when the shark is attacking the boat and the electronic device is used you can hear the shark roar. Sharks cannot produce this sound since they have no vocal cords.
Factual error: The Pentagon is the largest office building in the world. It has seven floors, 28 kilometers of corridors and 620,000 square metres of office floor space. The idea that the entire building could be searched in one afternoon by six people is beyond absurd. If those six people could search an average of one office every five minutes and they worked twenty four hours a day, seven days a week they'd get through the whole building in 89 days and 15 hours. I don't think the punter they are looking for has a lot to worry about.
Factual error: In the warehouse scene with the wooden crates with maple leaves, even though a correction has been submitted saying a maple leaf was valid, the real mistake is the type of maple leaf used. The film shows a modern graphic style of leaf that did not come into use until the 1960s and appeared on the new Canadian flag in 1965. In the time of Capone, the maple leaves used to depict things Canadian looked like actual maple leaves and not like a stylized graphic.
Factual error: The heat from Dutch's body would warm the mud up in a matter of seconds (tested by the Mythbusters). It doesn't even cover all of his skin or his eyes. And the Predator isn't filtering his input for only large heat sources. His normal vision tracks in on a rat hiding just above Dutch.
Factual error: Some of the SS rank insignia is incorrect. Most of them do wear correct insignia, with two exceptions. Wagner, who is addressed as Hauptscharführer, actually wears the collar and epaulette insignia of the next higher rank of Sturmscharführer. In reality, Wagner held the lower rank of Oberscharführer. Frenzel is addressed using his correct rank of Oberscharführer, but oddly wears the collar patches of the lower rank of Scharführer and the epaulettes of the higher rank of Hauptscharführer. Bauer and Beckmann, on the other hand, wear the correct collar patches and epaulettes for the rank of Oberscharführer which they did hold.
Factual error: Austria is famous for its mountains and ski resorts, but certain parts of Austria are quite flat. And the border region between Bratislava and Vienna is VERY flat. No chance to cross the border over a mountain with a ski resort like shown in the movie, unless you take a 600km detour with three more border crossings.
Factual error: After Robocop stops the criminal from robbing the convenience store by bending his machine gun, the robber tries to run past him, only to get clotheslined by Robocop. The direction the robber flies after getting hit defies all physics. (00:35:15)
Factual error: Ronnie Cox is shot in the heart at point blank range by Brigitte Neilsen, and it looks to me like she's using a large caliber handgun. Keeping track of the action of the film tells us that Cox is sitting up in bed chatting to his friends just three days later. What nonsense. Even if he did survive (unlikely) he'd still be in Post-Op Intensive Care at that stage. He wouldn't be conscious, let alone allowed visitors.
Factual error: When 8-ball gets shot, in the shot which shows the platoon ducking near a wall with Cowboy, Joker and Animal Mother in the front, there are two weapon related errors. Cowboy's M-16 has a nickel (silver colored) firing assembly and Joker's M-16 has an A2 type pistol grip. The A2 types were introduced somewhere around the 80s, and nickel plated assemblies are rarely used (and were invented after Vietnam, too). The nickel assembly is visible at the beginning of the shot, and you can see the A2 grip when Joker is changing magazines (while Cowboy shouts cease fire).
Factual error: In the beginning of the movie just prior to the Bakersfield Massacre, the camera cuts away from Arnold periodically and shows a computer schematic for his location. The very first coordinate that we see is 29º, 43' N by 119º 23' W and is off the coast of Baja California. The last coordinate that we see is 45º 4' N by 119 8' W and is in north-east Oregon. So, in the 35 seconds or so between these scenes, Arnold's helicopter traveled approximately 1050 miles. That's one fast helicopter. This cannot be explained by saying that they just shortened the trip for the movie because in the first computer schematic you see Bakersfield in the distance which is certainly not 1050 miles away. (00:01:35 - 00:02:10)
Factual error: The bad guys attach over a pound of Semtex to the hull of the First Lady's yacht. When it explodes, the blast shatters the windows in a house a mile away, yet apparently doesn't impact the hull. Even as the vessel burns for 5 minutes, there is no discernible list.
Factual error: In the "Groovy" shed scene, Ash holds a double-barreled shotgun in one hand and saws through the gun barrels with his newly-mounted chainsaw in about 2 seconds flat. He could no more cut through a hardened steel shotgun barrel with a chainsaw than he could cut through a marble counter-top with a butter knife.
Factual error: When Riggs and Murtaugh are at the indoor shooting range, Riggs shoots a smiley face at long range. Every shot makes Mel Gibson blink and twitch from the bang. No expert marksman would react like that to the gunshot. Nor could his shot placement be so accurate with that reaction.
Factual error: This film begins with a foreboding quote attributed to Edgar Allen Poe: "Sleep. Those little slices of death. How I loathe them." Problem is, Poe never wrote any such thing (and neither did Henry Wadsworth Longfellow), despite decades of misquotes and misattributions across the Internet. So, where did the quote actually originate? The answer is Walter Reisch, lead screenwriter on the 1959 film "Journey to the Center of the Earth." In Reisch's screenplay, the antagonist Count Arne Saknussemm is urged to get some rest, to which he memorably replies, "I don't sleep. I hate those little slices of death."
Factual error: In the farmhouse bedroom scene, the lead character wakes up and a close up shot of the alarm clock shows it is 5AM. Full sunlight is coming through the window, and an exterior shot shows the sun shining on the house and hay bales. The narrative lead-in just explained that it is early October on a farm near Dallas, Texas. The earliest sunrise occurs near Dallas in October is 6:40AM. (00:04:00)
Factual error: In the movie's opening scene, it's night and we see the full moon. There's an elderly priest lying in bed. The next morning we learn the priest has suffered a stroke and been taken to the hospital. That day, Prof. Birack pauses before entering a campus building to look toward the sun. We see a thin crescent moon near the sun, as if there will be an eclipse in the next few days. That night, Brian is waiting outside a campus building for Catherine to come out. He looks up at the full moon. In following days, other characters see the daytime crescent moon, still approaching the sun. It's impossible to see the full moon at night AND a crescent moon during the day in that brief a time span. It would be more like 12-14 days for the lunar phase cycle to progress from one to the other (much less back again).