Factual error: The cap badge worn by Captain Halliday of the RAMC is the Queen's crown version, which didn't come in to use until the 1950's. It is also made of brass, when it should be in a bronzed finish for officers.
Factual error: The German pilot held prisoner is wearing a watch that is not correct for the 1940s. His watch is a late 80s / early 90s style watch.