Character mistake: At the end of the episode, while Col. Potter is in the helicopter asking where they are, the pilot says they are about 10 miles west of Inchon. Col. Potter says this is no good and he tells the chopper pilot to "head west, towards Inchon." If they are already west of Inchon, heading west will take them further from Inchon.
Suggested correction: Potter tells the pilot to head to a different city, Chuksan (not sure of its spelling).
Continuity mistake: When the two soldiers get into a brawl in Post-Op, it's daytime. When Potter talks to Mulcahy, it's night. Then Klinger tells Mulcahy he's needed to break up the fight, it's daytime again.
Suggested correction: In scene 1, set in the day, the Greek soldier is wearing a dark blue jacket and a light blue shirt. In scene 2, set at night, Father Mulcahy is wearing a black shirt and a brown robe, and resting before bed. In scene 3, set during the day, Father Mulcahy is wearing a black shirt, a sweatshirt, and a baseball cap. He is punching a speed bag. Klinger says there has been another fight between the Greek and the Turk. The Greek is not wearing a jacket. Scene 3 is from a different day than Scene 1.
Character mistake: Hawkeye and Trapper make Tuttle an alumnus of "Berlin Polytechnic" and translate that (wrongly) as "Berlinishes Polytechnikum". Berlin's polytechnic university was named "Technische Hochschule Berlin" at the relevant time - and at no time offered a medical curriculum. To study medicine in Berlin, Tuttle would have to attend "Freie Universität Berlin" instead.
Suggested correction: And how are Hawkeye and Trapper suppose to know that? They are after all, making all this up. It is never meant to be factual.
It is intended to fool Margret and Frank, so it has to be assumed that they meant to pull it off. Hawkeye says "It can't be any place they'll check", which is why they select a German university in the first place. That shows it is indeed meant to be if not watertight, then at least convincing. To use an university you don't know the proper name of doesn't make sense under these circumstances.
Other mistake: Many times during the series, soldiers are around the OR carrying a loaded weapon (magazine attached for example), when there is a sign outside the entrance that says "all weapons must be cleared before entering the building" or similar.
Suggested correction: With the rampant rule breaking seen in the show, why would this be a mistake?
Trivia: Radar and Franks Burns in real life were just the opposite of the characters they played on the show.
Suggested correction: "Just the opposite"? In what sense? According to whom? Very vague.
What he meant was Larry Linville (Frank Burns), despite playing a nasty, dumb character onscreen, was in fact incredibly sweet and intelligent and loved by the cast. Gary Burghoff (Radar), on the other hand, despite playing a sweet, likeable character, was in fact rude, arrogant and combative with cast members. He apparently didn't enjoy doing the show and wanted out when possible. No one missed him.
Continuity mistake: In this episode, a "Spirit Post" is placed in the middle of the compound, later removed, then replaced at the end of the episode. It is never seen again after that.
Suggested correction: It was probably left behind during one of the bug outs that happen. We have seen at least 2 in the series.
Goodbye, Farewell, and Amen - S11-E16
Deliberate mistake: BJ mentions to Charles that if they don't sign the armistice it will be the second time in 2 years and then he will miss his daughter Erin's second birthday. This is BJs 7th season and when he arrived at the beginning of season 4, Erin was already born, making it absurd that seven years later she could still be one year old. Because the real war lasted 3 years and the show 11, there are obviously some errors like this that can't be avoided but this was blatantly egregious.