The U.S. Marines have American flag patches on their shoulders. Marines do not wear American flag patches.
In the mission "Going Hunting", Iranian fighter jets are depicted to be Sukhoi 27/35's. The Iranian air force's primary fighters include mostly American fighter jets, including the F-5E Tiger II, the F-4 Phantom II and the infamous F-14 Tomcat (noted to be the only country other than the U.S. to have them). Other aircraft were Russian and french made aircraft that they took from Iraq in the First Gulf War, including Mig-29', but not Sukhoi 27s.
In the missions that take place in Tehran, many stores and traffic signs are written in Arabic. In reality, Iran's official language is Persian and no one speaks Arabic but a small minority in Iran.
When Blackburn is being interrogated about the female pilot, he mentions BDA. (This happens in the cut scene before the Going Hunting mission)
The agent says Battle Damage Assessment, but this is incorrect. The acronym stands for Bomb Damage Assessment, and is used to gauge the effectiveness of an air strike. (Bomb damage is much more specific than Battle Damage).
It is possible for vehicles to explode very violently and kill NPCs or the Player. Gasoline is not explosive, so this should not be possible.
Grammar mistakes in subtitles.
In the mission 'Going Hunting', the subtitles may state that the Player has hit an enemy before the missile hits and the pilot says the contents of the subtitles. This would indicate that the probability of the missile hitting is predetermined rather than random.
Spelling mistakes in in-game subtitles.
Allied NPCs do not seem to recognize Sergeant Blackburn's rank and give him orders.
In the Mission "Going Hunting", the Mehrabad airport seems to be in the middle of the desert with a few buildings around it. In reality, the airport is located in a very urban and populated area and has little to no unoccupied land around it.
Lieutenant Hawkins is misidentified by Agent G. as being an F-18 pilot. Lieutenant Hawkins is a weapons officer, not a pilot.
When reloading a bolt-action rifle, the animation shows the cartridge currently in the chamber being ejected rather than being held in by the Player's character.