Although the nitpicker in me has to point out that the film is heavily edited to fit the dialogue (there's a shot at about 3'25" where you can see them bombing a paper cross pinned to the cliff which is taken from earlier in the film when 633 squadron are training in the Scottish highlands).

I remember reading somewhere that many of the dog fights in Star Wars were copied from the film The Battle Of Britain, but then that, 633 Squadron and many other classic British war movies were made by people who actually fought in the war. If you want a film to look realistic, and you weren't there yourself, copying from films made by those who were is probably the next best thing.