Factual error: The ribbon of Richard Burton's Distinguished Flying Cross is on upside down. The Air Force Cross following it is the right way up. The stripes on both should point the same way, as they do on the uniform of his colleague in the mess. Nobody would be allowed to get away with a mistake like this - another officer or senior NCO would soon point it out. In addition, as a long-service veteran (his colleague says he served in the Battle of Britain) he should be wearing the ribbon of the 1939-1944 Star (as it was then), which was issued to all qualified personnel from 1943.
Other mistake: In the early part of the movie, Rommel is addressing his Officers on the Atlantic Wall. The "mid-shots" and "close-ups" are shot against a back projection. Rommel turns to view the sea/horizon and the view is exactly the same as their "mid-shots". The effect is a horrendous "jump-cut".
Pluskat: Lieutenant-Colonel, the invasion is here! Five thousand ships! There-there must be over five thousand ships out there!
Ocker: Now get a hold of yourself, Pluskat. The Americans and the British don't even have half that many ships altogether.
Pluskat: Dammit, if you don't believe me, then come up here and see for yourself! This is fantastic. It's incredible! I-I just can't believe it!
Ocker: My dear Pluskat, what course are those ships on?
Pluskat: STRAIGHT FOR ME!