Good-Bye Radar: Part 2 - S8-E5
Other mistake: When Potter enters the Swamp, his rank insignia is placed wrongly, with the feet of the eagle pointing to the front of the collar. The feet should point toward the shoulder side of the collar, as they are the next time we see Potter.
Good-Bye Radar: Part 2 - S8-E5
Other mistake: As the camera cuts to Hawkeye and Margaret working, the man behind her is holding a chest X-ray, but it's upside down, which would be useless as a guide.
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 ★