In the summer of 1940, Germany sent armadas of bombers and fighters over England hoping to lure the RAF into battle and annihilate the defenders. Day after day the RAF scrambled their pilots into the sky to do battle up to five times a day. Britain's air defense bent but did not break. All that stood between the British and defeat was a small force of RAF pilots outnumbered in the air by four to one. After pushing back the armada, Winston Churchill declared: "Never before in human history was so much owed by so many to so few."

But how did they do it? The answer is effective tactics, plenty of bravery, and a change in German strategy that squandered all their gains.