Continuity mistake: When Hawkeye and BJ unload the chopper, the dog, Corp. Cupcake, is lying on its paws in the long shots and on its side in the closeups. (00:03:35)
Continuity mistake: As Hawkeye talks to the wounded man on the chopper, the speed of the rotor blades changes several times in the scene. Looking at Hawkeye, the blades are moving fast; in the reflection, much slower.
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 ★