Continuity mistake: When Hawkeye's saying goodbye to the nurse in the morning, he reads "35591715" from her dog tag and says, "Even your number is pretty," and then he makes another date with her and again reads her dog tag, but now the number's "39591715."
Visible crew/equipment: While Margaret's reading the story of 'The Three Bears' to Kim, just as Frank walks into the tent the curved chalk foot mark can be seen on the floor.
Other mistake: When Hawkeye and Trapper are arguing with Henry about not sending the little boy to the orphanage, Henry says, "Look, you think I wanna send this little fella away? I got two kids of my own. I'm a former child myself," but at the end of season 1 Henry's wife delivered a boy, whom Henry was aching to be with, so Henry really has three kids.
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 ★