When Baker gets into his Spitfire it carries the squadron code 'LO', but the shots of the Spitfires taking off show them with the code 'SH' (used by 64 Squadron) and shots in the air show the code has returned to 'LO'.
Both night raids, Berlin and Dortmund, use footage of the same city by night.
The following items are 'goofs', but may have been made deliberately by the filmmakers in the interests of war-time security: The real 61 Squadron flew Hampden bombers, not Lockheed Hudsons. Hudson bombers were not used in bombing missions over Berlin, with the main role for these bombers being in Coastal Command in Europe. The real 32 Squadron, which Baker flies with in the Dunkirk scenes, flew Hawker Hurricanes and not Spitfires. When Baker gets in the Spitfire, it carries the squadron code 'LO' which was the code of the 602 Squadron and not the 32 Squadron he is supposed to be flying with (it used KT and GZ). 602 Squadron aircraft were used for shooting the film at Prestwick
Close shots of Baker in the Spitfire show a canopy more like a Hawker Hurricane canopy rather than a Spitfire. It is distinctly different to the canopies of the Spitfires in the background.
At the airfield, Carol's car is backed into by another car, hitting her's on the passenger side. But, in subsequent shots, there isn't even a scratch on her car.