Plot hole: In the Bendwater escape, the security cameras show the time outside the prison as 15:59, but a few cuts later, there's a shot of Stallone in his cell with the timecode being 15:56. That's not a continuity mistake, since it turns out that Breslin rolled back the security monitor, the problem is, he is shown doing that at 15:57, and barely rolling the tape past the point when he stands up. By the time the guards are looking at the monitor after 16:01, the tape showing him nice and quiet 3 minutes before would have already rolled to the incriminating part where he breaks out of the cell. (00:06:50 - 00:13:25)
Character mistake: Schwarzenegger welcomes Portos saying "Your name. The fourth Musketeer. It's a good name." Port (h) os was one of the original three musketeers in the eponymous novel. To be "the fourth", his name should have been D'Artagnan. (00:31:55)
Character mistake: The notice of hold for the check says it's from the Southern Grand Caymen Bank. I wouldn't trust a bank that can't spell the name of the country it is in (Cayman Islands). (00:57:50)
Continuity mistake: When Abigail is talking to Clark about the bounced check, Fifty Cent in the background has his hand in his pants' pocket between shots. (00:58:00)
Other mistake: When Ray attempts his first escape, he emerges from the front right side of the fire engine. When he explains how he did it, he appears too far in front of the fire engine to make it look like he was underneath it. (01:07:25 - 02:13:40)
Character mistake: Error in reading of the "sextant." Mark is somewhere at 33°, but Stallone said 30° 22 minutes. I suppose they thought there were 60 minutes between marks 30 deg and 40 deg (actually there are 10°) and calculated the difference at 22 minutes. (01:13:55)
Other mistake: After the Doc looks in the book that Breslin told him to, he tells the guards to go get him. He says to go get Breslin from A Block, however the subtitles say E Block. Breslin was moved to E Block and then moved back to A Block after he negotiated with Hobbs. But the Doc says A when the subtitles say E. (01:20:05)
Audio problem: The helicopter appears in front of the window (like, a few feet away) of the command deck of a ship in the middle of the ocean, with the ship being in full alert and with guards all around the premises but who all somehow missed its deafening arrival. (01:35:50)
Continuity mistake: When Schwarzy tells the helicopter pilot to "Go down!" to fetch Breslin, the helicopter gun is missing the ammo belt. (01:40:10)
Factual error: When Ray figures out he is on the ship, he makes it back to his cell, creating a flood along the way, he then swims through a lot of water. When he returns to his water drenched cell and escapes with Victor, his clothes are bone dry. (01:54:30 - 01:55:20)
Suggested correction: I really don't think so. Their clothes are completely soaked, like their hair and skin.
Nope...watching the scene many times in slo-mo, it's clear that Arnie's shirt is soaked, but Sly's is just as obviously dry.
In the first shot when he comes out from the cell he is more than knee-deep in water, with water splashing everywhere, and there are showers of water everywhere when the shot changes: if the shirt were dry you would see stains created by the water spashes and by soaking wet Arnie leaning on him and touching him, since it is impossible for a dry shirt to stay dry through what we see onscreen, let alone the multiple takes most likely they had to do: instead the color of the shirt is uniform. Plus his hair, face, his T-shirt underneath is wet, why would they throw a dry shirt on him on that mess, and how would it stay dry? I think it's simply the light to make them appear different, Arnie is on the darker side of the corridor. However, that's just my observation.
Plot hole: The most secure prison in the world, designed with the advanced schematics of world leading prison-building architect (J.D Ray Breslin) has cameras somehow interconnected to one another so tightly that physically neutralizing one puts every other camera out of commission as well.
Character mistake: Stallone says he knows they are in the Northern hemisphere because of the way the water goes down the toilet. The Coriolis effect has no impact on water in the toilet.
Plot hole: The Tomb is supposed to be a top-secret off the grid prison that nobody is supposed to know about yet the schematics for the place are conveniently left available online such that a hacker can search for it with no problem, on top of that the fact that it's known on the outside world as "The Tomb" suggests it's more well-known to people that it should be.
Plot hole: Breslin is supposed to going to an off the grid prison, a place nobody is supposed to know about outside of the prison except for Clark, who is the only one who really knew where Breslin was being sent. So why in the world would there be a warden as the "contact on site" that Breslin would inform if things didn't go well? It also makes no sense that Breslin would have an evacuation code when his own people have absolutely no idea where in the world he could possibly be.
Plot hole: In this top level state-of-the-art security prison with transparent walls, cameras everywhere and no civil rights concerns since it's all illegal, there's not a single hidden microphone in the communal parts. Even worse, the wardens never search the inmates, who can smuggle freely all sort of stuff, sometimes in the most blatant way (like when the protagonist gets stitches for his leg).