Throughout the film, Montgomery Clift's army uniform has sergeant stripes, then it doesn't, then it does, etc.etc.
When the airmen are leaving Hickam Air Force Base, Hawaii, they take off in the dark; however, when they see Diamond Head below, it's broad daylight.
When the aircraft is over Germany it is flying parallel to the Rhine but in the next shot from the cockpit it is crossing the Rhine.
When Sgt, McCullough (Monty Clift) is talking with reporter O"Malley at the 29 -30 min mark, the heights of the two men change depending on the camera angle, from one angle O'Malley appears to be taller, from another angle they appear to be of similar height, compare their side by side scene at the 35 min mark.
When the white paint is first spilled on "Danny" (Montgomery Cliff) it splashed mostly on the lower part of the front of his uniform, from the chest down. Later, almost his entire uniform, front and back, had some paint from the shoulders down.
The "Russian fighter" that approaches one of the airlift C-54s is actually a US Air Force Republic P-47 "Thunderbolt."
Throughout the movie enlisted men, when saluting officers, fail to hold their salutes until after the officers have returned it--a violation of military protocol.
When the Navy transports show up to join the Airlift, the Air Force men shout about the "Navy C-54's." Actually, the Navy called their cargo plane R5D's.
Danny's rank is noted as a T/SGT which is a technical sergeant and the correct sleeve insignia would have capital T under the three Chevrons but Danny's uniform during the film does not have the T.
Paul Douglas is giving a brutal beating to his former German military prison guard, but the military police don't arrest him, but chase after Montgomery Clift.
In an early scene the USAF guys and USN sailors are singing, teasing each other. At the end of the scene some of the sailors in the truck stand up and at that moment the truck starts moving. So suddenly that at least two of them appear to fall off the back of the truck.
The Airlift was in 1948. Paul Douglas's character (an ex-POW who wears an 8th AF shoulder patch) says that for the past seven years he'd sought revenge against the former German prison guard who'd mistreated him. The US bombing campaign against targets in Nazi-occupied Europe didn't begin until 1942, meaning that Douglas could not have been shot down and captured in 1941.