Quoting: Polanglik
I read somewhere that 1 in 3 RAF pilots were Polish.
My sources tell me Polish pilots constituted 5% of RAF during the Battle of Britain. They were responsible for a disproportionately high number of kills (12%), even though they were allowed to join the Battle when it was about 1/2 way through.
The Brits did not believe Poles could actually fly, so they made them train flying formations on the ground using tricycles. Some of the best pilots in Europe (and possibly the world) during WW2 were riding tricycles while British rookies were slaughtered in the air.
Lt-Colonel - Gabreski of USAF In 1943 joined RAF 315-th (Polish) Fighter Squadron "Deblinski" since the Americans believed he was not good enough to join any of their air units. He became the top U.S. ace of WW2 in Europe with 28 air-to-air combat victories and 2 enemy planes destroyed on the ground. Gabreski's parents were both Polish.
If you want to learn more I recommend this book
URL