Visible crew/equipment: When Frank and Hot Lips are walking into the mess tent for Frank's surpise party, if you look in the window to the right of the door, you can see a person silhouetted, throwing leaves into the wind.
Continuity mistake: In Henry's office, the white cloth Radar has on his ears changes positions from shot to shot.
Continuity mistake: As Radar is sorting mail, and Trapper makes a joke, Radar starts to put a letter down. After the angle change, he puts the letter down again.
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 ★