The number markings on the American Fighter Jet's nose change between 104 and 114 in different shots.
After the primary target is activated and the rescue helicopter is cleared for launch, we see a a SH-60 Seahawk taking off from the aircraft carrier (we can therefore assume that this is the rescue helo). Instead, the squad are rescued by a IAR 330 Puma (Romanian verions of the original SA 330 type), this Helicopter is NOT operated by the US Navy, indeed most of the helicopters in the movie clearly have markings for the Romanian Airforce, who are a user of this type.
At the end of the movie when one of the American soldiers are in a tower like building and fires a rifle out of the window. When shot from the outside the soldier has one kind of rifle, but when shot from the inside the soldier has another kind of rifle.
In the opening sequence a fighter pilot acknowledges cleared for takeoff, presses a toggle on the dash, and we see a gauge spinning up past "1.5" followed by a tail view of the jet taxiing out. However the gauge we saw was clearly marked "MACH", and going MACH 1.5 while taxiing on the ground in a jet fighter is a bit difficult.
In the scenes for satellite imagery for the reactors, it shows "image analisys" multiple times above the imagery, as opposed to "image analysis".
At least some of the aboveground scenes at the "nuclear power plant" were actually filmed at an abandoned sewage treatment works. Trickling filters, sedimentation basins, digesters, and other structures associated only with sewage treatment plants are plainly visible in the scenes.
On the aircraft carrier, the CO is wearing a ball cap that reads SSN 798, which is supposed to be the designation of the carrier. However, SSN is the abbreviation for nuclear attack submarines in the US Navy, not for aircraft carriers.
In the "dogfight" near the end the US pilot calls "Fire Fox 1" which designates launching a Sparrow/AIM-7. The missile subsequently launched is something else entirely.
Many of the dogfight sequences are from Top Gun. They have merely been color graded to look differently.
During the US/Russian jet fighter dogfight sequence it is clear that both pilots are sitting in the same cockpit set. The view of the seat behind the pilots is identical, even though one pilot is flying a MiG and the other is flying a Tomcat.
Close to the end of the movie, when the American is shooting out of the tower, you later see an enemy shot in the head. However, you see the blood spurt out the back of his head a second before you actually hear the bullet hit and the dying grunt of that enemy.
When the team is jumping from the airplane, you can see seven people but in fact there are only six people in the team. The seventh chap is the cameraman who is shooting the guys as they are paratrooping.
You can see the padding that the stunt guy falls on in the scene where 'The Painter' shoots the guard from the guard tower.