Henry, Please Come Home - S1-E9
Continuity mistake: As Henry is receiving his medal, Hawkeye walks up and stands close behind a man who is standing up and two women who are sitting down. The camera angle switches to show Hawkeye talking to Trapper and now they are standing behind two standing women. (00:03:55)

Henry, Please Come Home - S1-E9
Other mistake: While Radar's in post-op waiting for Henry's arrival he's seen reading Marvel Comics "Captain Savage and His Battlefield Raiders!" issue #10, published January 1969. It's one of the 19 issues in this comic book series which were originally named "Captain Savage and His Leatherneck Raiders," and it ran from 1968 until 1970, many years after the Korean War ended. This comic is also seen in the episode "Tuttle" later this season.
Henry, Please Come Home - S1-E9
Continuity mistake: When Henry's being given the Special Citation of Merit - 4th class, in the wide shot of Hawkeye and Trapper there's dark facial stubble on Hawkeye's face, but in their closeups there's barely any stubble on his face.
Henry, Please Come Home - S1-E9
Continuity mistake: The message Radar is presenting to Henry goes from chest height on Henry to face height between angles.
Henry, Please Come Home - S1-E9
Visible crew/equipment: After Reveille has blown, Radar comes in, and gets items thrown at him. As the door closes, there's a reflection of the studio lighting on the glass.
Answer: The C-42 was a military variant of the Douglas DC-2. Very few C-42's were built, so it's questionable that Potter would specifically have seen that particular model, but, given his military background, it's not entirely unreasonable that he might use the military designation even when the aircraft in question is actually a civilian DC-2.
Tailkinker ★