Corrected entry: The movie shows a hurricane flying upside down in a straight line, impossible. Hurricanes are gravity fed fuel and would cut out if upside down.
Corrected entry: When Bader crashes his Bulldog biplane, and gets extracted from the wreckage, not a drop of blood is seen. In the actual crash, Bader suffered multiple fractures and arterial bleeding.
Correction: Trivia, at best. The film was made in 1956 - showing blood in those days was extremely rare. This is a stylistic choice due to the strict censorship laws of the time, not a film mistake.
Correction: Firstly, that's a real Hurricane flying upside down - LF363, one of the BBMF's Hurricanes. There were no models or CGI in 1956 - there were enough Hurricanes still flying to use the real thing. It was evidently fitted with the RAE restrictor. Informally known as Miss Tilly's Orifice (yes, really) a simple device designed by RAF engineer Beatrice "Tilly" Shilling which allowed the non-fuel injected Merlin engines to continue operating when inverted or in a steep dive.