August 1940 saw the German Luftwaffe try to establish air superiority over Great Britain. Hitler's planned invasion of that island was running out of time - the English Channel gets notoriously stormy in the autumn, and mid-August was getting perilously close to autumn. But Hermann Goering assured the Fuhrer that he had the Royal Air Force on the ropes. One more big push would break RAF Fighter Command.
August 18 was that big push.
But it didn't go that way. Hundreds of RAF Fighters rose to savage the German bombers. While this "Hardest Day" was just about exactly a draw in terms of losses, it showed that the RAF was most definitely not on the ropes. While the Battle of Britain would go on for weeks, Hitler's mind was already shifting to the Eastern Front. In Churchill's immortal words, never had so many owed so much to so few, those who flew sortie after sortie on that Hardest Day.
Three Quarters of a Century later, those Few are few indeed. Per Ardua ad Astra, indeed.