The film's closing epilogue states: "By the year 1951 all the Czechoslovak RAF airmen were released from the labor camps. But they remained outcasts for most of their lives. It was only in 1991 that the survivors were rehabilitated and recognized for their wartime service."
The most expensive Czech movie so far. The most expensive scene from total budget of 8 milion USD is where British Spitfire attacks German train. It cost more than the whole Oscar-winning Sverak's movie Kolya (Kolja).
In one scene set during the 1939 sequence in Czechoslovakia there is a reference to Hitler and his mistress Eva Braun. Braun's very existence, let alone her status as Hitler's mistress, was not widely known to the public until the announcement of their marriage just prior to their dual suicide in 1945.
During training on the "bicycle Spitfires" and later during actual missions, the pilots fly in the "finger four" formation. This wasn't officially used until at least two years after the depicted events. Experienced pilots had been experimenting with it, but it would not have been used by trainees.
Oberleutnant Hesse: I understand how you feel. A German officer would shoot himself in a situation like this. But you can... You are a different type of person. Heil Hitler!