Continuity mistake: As Ames is pitched the idea of diet and exercise, he has his fork up with a bite of egg on it. When Hawkeye reaches for the fork, it's upside down and clean.
Visible crew/equipment: When Colonel Potter surprises everybody with his "little Olympics" idea in the mess tent, after Margaret comments, "I just know I'm not going to have anything left for Donald," at the start of the next shot the boom mic casts a very quick moving shadow on BJ.
Visible crew/equipment: While Colonel Potter has everyone gathered in the mess tent to surprise them with his "little Olympics" idea, the studio soundstage is visible at the top, left side of the screen.
Continuity mistake: Near the end, Margaret and her husband are shown leaving for their honeymoon in a jeep. You can see Trapper and Hawkeye in the background with a wheelchair. Then it cuts to an emergency room surgery session that appears to be a throw-in scene showing them worn out. Then, after the commercial, it shows Margaret leaving again and Trapper and Hawkeye with the wheelchair in a full scene.
Other mistake: When Penobscot is approaching the group, you can make out "4077 USA MASH" on the bumper, even though the the numbers and MASH are partially obscured.
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 ★