The General's Practitioner - S5-E20
Continuity mistake: Near the beginning, while Col. Bidwell is watching Hawkeye operate, in the closeups he is standing by the window but in the wide shots he is standing in a different part of the O.R. (00:04:00)
The General's Practitioner - S5-E20
Visible crew/equipment: When the Colonel that Hawkeye referred to as "Bozo" is talking to General Korso on the way to the 4077th to get Hawkeye, you can see the shadow of the camera on the Colonel's lap.
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 ★