Visible crew/equipment: When Frank climbs into the jeep belonging to Major General Cornell Dickering, the MPs show up at the same time that BJ and Hawkeye walk up to join the fun, and during this scene there's a T-mark (albeit a dusty one) on the ground at the driver's side of the jeep.
Continuity mistake: When Radar and Burns leave the tent for morning parade, Radar's clipboard acquires a pencil. (00:02:50)
Continuity mistake: During the shelling on the road, BJ gets very muddy. When they get to the bar, he is much cleaner - e.g. all the mud has disappeared from his right arm. (00:44:30)
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 ★