Deliberate mistake: After having wrestled with Santini in his office, Col. Virgil Hedgepath tells Santini, "And no more assaulting corporals in the latrine." Marines use the naval term "head" in refering to the restroom, and would never call it "the latrine." However, since "latrine" is better known to civilians, this could be a deliberate mistake by the film makers.
Deliberate mistake: In the scene where the Punks follow the Warriors into the bathroom, Rembrandt sprays the head punk with his red spray paint. However, the spray coming out of the can is clear, not red.
Deliberate mistake: None of the helicopter's in the movie have the Army markings seen on Vietnam era Hueys. The most you'll see is some crooked, faint and inaccurate stencils in the wrong spots. (00:37:50 - 00:51:25)
Deliberate mistake: When the inmates first leave their cells we see at least 2 that have white or light colored shirts on instead of prison blue.