September 15th in known as ‘Battle of Britain Day’ and each September it is celebrated to commemorate the day in 1940 when the Luftwaffe attacked Fighter Command with all its might and lost. Throughout September 15th 1940, Fighter Command had to use everything at its disposal to counter the two main attacks by the Luftwaffe but by the end of the day any threat that Fighter Command had faced had been repelled. While the Battle of Britain continued until October 1940, the real threat posed by the Luftwaffe was broken on September 15th and with no control of the skies or the English Channel, ‘Operation Sealion’ had to be called off saving Britain from any chance of invasion.
September 15th fell on a Sunday in 1940. The German High Command had planned to issue new orders for ‘Operation Sealion’ on September 17th. Therefore control of the skies was vital if the plan was to proceed and the invading barges were to be safe from attacks by the RAF. On September 14th, the commander of the Luftwaffe, Hermann Göering, had sent out instructions that an all-out aerial assault was to be made on southern England on September 15th.
While the Luftwaffe had suffered unexpectedly high loss rates prior to September 15th, they had learned one key thing. If they flew at a high altitude, they had on occasions taken Fighter Command by surprise. That was all they knew – German intelligence had failed to discover that the radar stations that were dotted around southern and eastern England were only effective up to 20,000 feet. Luftwaffe pilots simply believed it was because Fighter Command’s Spitfires and Hurricanes took time to reach high altitudes. However, to a degree this was immaterial. What they had learned was that the higher they flew the better the chances of their success.
British intelligence using radio intercepts had already informed Sir Keith Park that a large attack by the Luftwaffe was to be expected but he was given no date – just that it would be soon. Park’s 11 Group was expected to confront the bulk of the attack and Park, as 11 Group’s commanding officer, had done what he could to make it as effective as was possible given the rates of attrition it had suffered since the start of the battle.
During his breakfast on the morning of September 15th, Park was informed of a large build up of Luftwaffe forces along the French coast. Park concluded that this was the start of the huge raid he had been warned of. To an extent the weather helped both the Luftwaffe and Fighter Command. Clear skies with just a minimal chance of cloud and rain meant that the Luftwaffe had no clouds to use to disguise their journey – a bonus for Fighter Command. However, the clears skies also meant that the Luftwaffe could clearly see incoming attacks by pilots from Fighter Command.
Ironically, September 15th was the day that Winston Churchill chose to visit Fighter Command at 11 Group’s headquarters in Uxbridge. Park escorted Churchill and his wife to his bombproof command centre fifty feet underground. Park was informed of a build-up of Luftwaffe aircraft near Dieppe and Calais. Park ordered that Biggin Hill, Hornchurch and Kenley were to be put on ‘stand by’. When it became clear that the size of the incoming force was far greater than initially expected, Park ordered all of 11 Group to be at ‘stand by’. At 09.30 two large Luftwaffe forces approached the southeast coast but then turned back to France. It is possible that the tactic of sending a force out and then recalling it was what Fighter Command called a ‘feeler’ – seeing what response Fighter Command would make to such a force. Park ordered 11 Group to ‘stand down’.
At 10.30 a very large Luftwaffe force was detected gathering between Calais and Boulogne. However, it was the sheer size of the force that benefited Park as it took so long to form up. Minding this bomber force meant that Me-109’s burned off fuel that they could not afford to. This gave Park the time he needed and 11 Group was again ordered to ‘stand by’. It was at this time that Park told Churchill that a “big one” was expected and after examining the map in the operations room Churchill told Park “there appear to be many aircraft coming in.”
By 11.00 it was clear from radar that over many bombers were approaching with an unknown number of fighter escorts and they were estimated to cross the coastline at Dungeness at 11.45.
Between 11.05 and 11.20 twelve fighter squadrons were scrambled – 4 Spitfire and 8 Hurricane. They faced a very large Luftwaffe force that was two miles across and flying between 15,000 and 26,000 feet. Flying among the bombers were Me-110’s while flying above the whole force were covering Me-109’s. The size of the incoming force was such that Park ordered part of 12 Group to scramble. Between 11.35 and 11.40 a further eleven squadrons took to the air – 4 Spitfire and 7 Hurricane. In total Fighter Command had 23 squadrons in the air
As the Luftwaffe force crossed Kent, 11 squadrons from Fighter Command intercepted it. A further 12 were kept in reserve or used to protect London from incoming bombers. The intensity of Fighter Command’s attack led to one Luftwaffe pilot later writing that “we thought that the whole of the RAF was there”. The nearer the Luftwaffe bombers got to London, the more squadrons from Fighter Command joined in. Many of the Me-109’s escorts had turned back as they were low on fuel and this left the bomber force easy prey to the Spitfires and Hurricanes that seemed to surround them. Holding squadrons in reserve to protect London was a vital tactical move by Park. Luftwaffe bombers dropped their bombs randomly to lighten their load to facilitate a speedier return to occupied France and Belgium.
Fighter Command had fought over a substantial area in the sky – 80 miles long and 38 miles wide.
However, the day was not over for Fighter Command. They had fought the first of two huge waves. While the first wave returned in disarray, the ground crew of Fighter Command had to rearm and refuel their aircraft in readiness for another attack. At 13.30, radar picked up another large Luftwaffe force massing off Calais – 150 bombers escorted by 400 fighters. They were expected to cross the English coastline at 14.15. The ground crews had done their job, as every squadron that had fought in the morning attack was ready by 14.00. By 14.05, twenty squadrons were in the air. It was clear that the Luftwaffe’s target was again London. The size of the incoming raiders spread across a ten-mile front. The fighting was as fierce as in the morning attack. Those bombers that had managed to get across Kent and Surrey were faced with fifteen squadrons that had been tasked with protecting London, including Douglas Bader’s ‘Big Wing’. Bader later wrote that during this particular attack, Fighter Command “shot them to blazes”. Once again German bombers dropped their bombs at random and the intended target – docks in the East End – received just minimal damage. The incoming Luftwaffe formation had been attacked with such ferocity that bombs fell in Mitcham, Kilburn, Hammersmith and Croydon. Fighter Command continued to attack the bombers as they returned to mainland Europe.
That night the public was informed by the Air Ministry that Fighter Command had shot down 183 German aircraft. In fact, the real figure was 56. However, the inflated figure was a huge boost to morale. The damage to the Luftwaffe was more than just lost aircraft. Göering had told his men before the first attack that Fighter Command was down to just its “last fifty Spitfires”. In fact, they faced over 250 fighters. While it is difficult to measure a drop in morale, there can be little doubt that in the minds of the men at the sharp end of the Luftwaffe – the crews – Fighter Command was a very formidable opponent as their losses clearly indicated. Fighter Command lost 26 aircraft and 13 pilots were killed.
The significance of September 15th 1940 was recognised by Prime Minister Winston Churchill when he stated that the day was the “crux of the Battle of Britain”. The battle was to continue into October but without the control of the skies ‘Operation Sealion’ simply could not take place. September 15th ensured that the Luftwaffe was not going to gain such control. Pilot Officer Thomas Neil of 249 Squadron later said: “September 15th was a very special day.”