The "hour of destiny" was September 15th, a date thereafter commemorated as "Battle of Britain Day". The title has been disputed; Alfred Price, for one, says that September 15th "has singularly little to commend it.....the day when the British victory claim was furthest from the truth....." Yet, forgetting the "numbers game", it is hard to dispute Churchill's verdict that it was, in fact, "the crux of the Battle of Britain". He made that judgment in the light of his knowledge of what happened to Operation SEALION - which was, of course, from beginning to end, what the Battle of Britain was really about. The Official History sums up with clarity:John Terraine The Right of the Line Hodder & Stoughton 1985 pp210-211"If 15th August showed the German High Command that air supremacy was not to be won within a brief space, 15th September went far to convince them that it would not be won at all."
For Adolf Hitler and the German commanders, time was now running out. If an invasion was to take place on September 17th as planned, the lead-up would have to commence no later than today.....September 15th. The weather had shown, just how quickly it can turn at this time of year, and with winter not too far away, the German forces would have to take advantage of the better conditions that now seemed to prevail. Göring had sent out the instructions the day previous to all bomber and fighter bases that preparations for an all out assault on England was to be made on this day September 15th, bomber units were given times and flight paths of their attack. Over the last few weeks, the Luftwaffe had experimented with different flying formations, needless to say, none had really been successful, losses had still been high, but they had discovered that on the occasions that they had kept at high altitudes, they had on a number of occasions surprised Fighter Command.
