Visible crew/equipment: At the end, after Father Mulcahy says goodbye to Sarah, when it cuts to a wideshot we can see two actors' rubber T-marks on the ground. The first is behind Father Mulcahy's feet, a white T-mark (albeit dirty) where Sarah had been standing, and the second becomes visible when Klinger runs over and bumps into Kellye, he kicks up some dirt which causes the black rubber T-mark to flip up off the ground.
Visible crew/equipment: When Marina arrives in the chopper with the wounded, the array lighting rig is reflected on the chopper's windshield.
Visible crew/equipment: When a very tired Hawkeye's in post-op checking on Marina in the morning, the shadow of the boom mic can be seen on the window curtain at the top, right corner of the screen.
Visible crew/equipment: After the troupe's performance in post-op, when it cuts to Brandy in Margaret's tent we can see the boom mic dipping into view at the top, right corner of the screen.
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 ★