Sometimes You Hear the Bullet - S1-E17
Factual error: We see Pvt. Wendel trying to hot-wire a jeep to escape. He wouldn't have to hot-wire it, because vehicles assigned to a combat zone were equipped with an ignition switch, not an ignition lock, for the simple reason that keys get lost or mislaid all the time and in an emergency, having to track down keys for vehicles would be extremely detrimental to an unit's combat effectiveness.
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 ★