Revealing: Near the end of the film, there is a football game played between the rival MASH units. Although the game is supposed to be taking place in a remote location of Korea in 1951, late model 1960's automobiles can be seen driving on a nearby highway as the game progresses. This gave away the fact that the football scenes were shot at a university in Southern California.

Factual error: In the football game scene, the players all have helmets with modern style (1970's) face guards.In 1951, the time period of the film, no face guards were used.

Factual error: In the scene where Colonel Blake is taken away, there is a shot of an American flag with 50 stars. During the Korean War, the flag had only 48 stars.

Revealing: The driver who was supposed to drive Hawkeye to the camp, after Hawkeye and Duke have gone off with the stolen jeep and after he has poured his coffee over his commander, can't help laughing so hard that he has to cover his face at the end of the shot.

Factual error: When Hawkeye and Trapper arrive in Japan, as they approach the hospital in a Jeep, you can see a football field in the background. Look closely at the goalpost on the field. Instead of looking like an "H" (then in use), it is in the style used since the late 1960s: a bent single goalpost, a crossbar, and the uprights.

Continuity: In one of the early surgery scenes you see Trapper operating, although he arrives only later as the new chest cutter.

Visible crew/equipment: At the end of the surgery scene after Trapper's entrance you see a reflection of a camera in the window.