The Five Phases of Battle

The Battle of Britain is often defined as having a number of distinct phases typically marked by a change in German tactics.  The number of phases and the dates of each phase varies dependant on the source used.  For me Derek Wood & Derek Dempster define the phases in the most lodgical way in their book The Narrow Margin claiming that there were five phases to The Battle of Britain. These phases were:

• Phase 1: July 10-Aug 7
• Phase 2: Aug 8-23
• Phase 3: Aug 24-Sept 6
• Phase 4: Sept 7-30
• Phase 5: Oct 1-31

Phase 1 - The Contact Phase or the Convoy Battles (10 July-7 August)

British accounts consider the Battle of Britain to have started on 10 July. On this day the Germans began a series of daylight attacks on coastal convoys attempting to reach London along the English Channel. On the first day of the battle one formation of Ju 88s unescorted by fighters managed to attack Falmouth and Swansea without being intercepted, a rare occurrence later in the battle, while further east a force of around 60 German aircraft (one third bombers two thirds fighters) attacked a convoy. Five RAF squadrons intercepted the Germans, and generally had the better of the clash. Overall the Germans lost 13 aircraft, the RAF lost 6, but only one pilot, Tom Hicks, was killed.

The period of convoy battles forced the RAF to fly 600 sorties per day, many of them over the waters of the channel. As a result the British air-sea rescue organisation was quickly improved. This period also saw the first British aircraft type to be withdrawn. On 19 July nine Defiants from No.141 Squadron were attacked by a larger force of Bf 109s, and only three aircraft survived. The turret-armed fighter had been designed in a period when nobody was entirely sure what form aerial combat might take in an era of high speed fighters and bombers. One theory had been that speeds were too high for accurate deflection shooting, a possibility that might have made the fixed forward firing guns of the Spitfires, Hurricanes and Bf 109s obsolete. The Defiant was one of a number of aircraft designed to provide an alternative type of fighter, but it soon became clear that the fast monoplane fighter was king of the skies. After the disaster on 19 July the Defiant was withdrawn from the daylight battle.

In the month from 10 July to 10 August the RAF lost 96 aircraft, but shot down 227. The German daylight attacks on convoys sank 40,000 tons of shipping, but almost as much shipping was sunk by mines dropped relatively safely at night.

Phase 2 - 8-23 August - Coastal Battles

The second phase of the battle saw a dramatic increase the number of German sorties. They also began to cross the coast in large numbers for the first time. The rate of activity began to step up on 8 August, but from the German point of view the main part of the battle didn't begin until 13 August, 'Adlertag' or 'Eagle Day'. This was meant to be the day on which the Luftwaffe landed the 'knock-out' blow on Fighter Command which would be overwhelmed by two massive raids launched at separate points along the coast. During this phase of the battle most German raids hit targets near to the coast. This meant that of the vital Sector Stations only Tangmere came under prolonged attack, while Manston, Hawkinge and Lympne, all close to the Kent coast, also suffered.

On 8 August the Germans attacked a west-bound convoy, starting at Dover and following it to the Isle of Wight. The day saw the British lose 20 aircraft and the Germans 28 or 31 in a series of battles than moved slowly west along the channel. Bad weather intervened on 9 and 10 August, but the Germans returned in force on 11 August, attacking Dover, Portland and Weymouth. The British lost 32 aircraft, the Germans 38, in the most costly day of the battle so far.

On 12 August the Germans made their first and only major attack on the British radar network. Five radar bases were attacked (Dover, Dunkirk (there are a surprising number of Dunkirks in Britain - this particular one is just to the west of Canterbury), Rye, Pevensey and Ventnor). All five bases were hit, but the damage was variable. Dover and Dunkirk were able to continue operations without any delays. Pevensey and Rye were both damaged but were back in use by the next day. Only Ventnor was knocked out for a longer period, and it too was back in service by 23 August. A number of airfields were also attacked. Lympe and Hawkinge were both damaged, while Manston was briefly knocked out of operations.

After a number of delays the Germans had finally decided to begin their main effort on 13 August, 'Adlertag' or 'Eagle Day'. This grand attack got off to a bad start. Poor weather on the morning of 13 August meant that the main attack was postponed until the afternoon, but two formations didn't receive the cancellation order, and their Dorniers attacked alone. Five were shot down and six badly damaged, but they did manage to attack the Coastal Command station at Eastchurch (believed by the Luftwaffe to be a Fighter Command base).

The main attack came in the afternoon. This involved two major raids - one over Kent and Essex and one over Sussex and Hampshire. The hope was that Fighter Command would be unable to cope with two major raids and would be dragged out of shape in an attempt to respond, but Dowding's system coped well. The western attack was dealt with by No.10 Group, the eastern attack by No.11 Group. Once again the Coastal Command stations at Detling and Eastchurch were hit, as was Southampton. The day ended with the RAF losing 13 aircraft and three pilots killed, while the Luftwaffe lost 45 or 47 aircraft. So far Fighter Command was more than holding its own, but the Germans believed that they were winning great victories. General O. Stapf informed Halder that they had destroyed eight major air bases between 8-13 August, and that the ratio of British to German aircraft losses was 5 to 1 for fighters and 3 to 1 for all types. If Fighter Command was guilty of over-claiming, the Luftwaffe was far worse, and had a tendency to make plans based on these exaggerated claims.

Between 10 July and 31 October the British claimed 2,698 victories but achieved 1,733, so over-claimed by under 2-to-1. In contrast the Luftwaffe claimed 3,058 victories and achieved only 915, over-claiming by more than 3-to-1, and by twice a big a margin as the British. Any overall plan based on such inaccurate figures was bound to contain errors.
The Germans had one success on the night of 13-14 August when KG.100, soon to become famous as a elite bomber unit, managed to hit the Spitfire factory at Castle Bromwich. In the period between 14-23 August this success was followed by eight attacks on the Bristol factory at Filton and nine on Westland, Rolls-Royce and Gloster, but the only target to be hit was Bristol at Filton. 14 August was a quiet day and the Germans were absent on the night of 14-15 August, but it was clear from Ultra intercepts that this was simply because they were planning a major attack for 15 August.

The German attacks on 15 August were designed to overwhelm the British defences, using all three of their available air fleets to attack all around the country. The Germans expected to find the north of England virtually undefended, believing that Dowding must have moved his reserves south to replace the vast numbers of fighters they believed they had shot down. Instead Luftflotte 5's bombers and Bf 110s ran into the fighters of Nos.12 and 13 Groups. The overall German plan for the day was to attack Fighter Command's airfields in an attempt to provoke the decisive battle. The day began with an attack on the south-east that crossed the coast at 11.29 and hit Lympne. This was followed by the attacks in the north. One large German force attempted to attack Tyneside but was repulsed. A second formation attacked Yorkshire, where it had a little more success, but the main message of the day was that any formation not escorted by Bf 109s was very vulnerable when facing Hurricanes and Spitfires. Luftflotte 5's Bf 110s were not capable of protecting their bombers against attack.

The third major attack began at around 14.20, just at the attacks in the north were ending. This time the south-east was the target. Attacks on airfields largely failed, but two aircraft factories at Rochester were hit (Popjoy's and Short's). A fourth raid, this time against Hampshire and Dorset, was detected at 17.00 and the first raid, this time in the Dover-Dungeness area, began at around 18.15. At the end of the day the Germans had made 1,270 fighter sorties and 520 bomber sorties, and had lost 76 aircraft while the RAF had lost 34. At the time the British claimed 182 victories and 53 probable victories, one of the more exaggerated daily claims, but the day had still ended as a clear British victory.
On the same day the three air fleet commanders were in conference with Goering at Karinhall. During this conference Goering repeated that the RAF was the main target and ordered an end to raid on unrelated targets. He also suggested that the attacks on radar stations were ineffective and should stop. This suggestion was treated as an order and only two more attacks on radar stations were made during the battle. Although German losses were lower than the British believed, they were still very high, and on the same day Goering ordered that only one officer should fly in any aircraft.

The Germans carried out three major raids on 16 August. During the second raid Fl. Lt J. B. Nicholson of No.249 Squadron won the only Victoria Cross of the battle after staying in his burning aircraft to shoot down a Bf 110 (he then escaped from the burning aircraft and survived to receive his award). The same day also saw the Germans adopt a new tactic, with their fighters operating closer to the bombers to provide more immediate protection. This did make it harder for the RAF to reach the bombers, but also made the fighters less effective and reduced the amount of time they could spend over Britain by forcing them to zig-zag to match the slower speed of the bombers.

17 August was a quiet day, but 18 August saw the Luftwaffe make their first major attacks on the inland sector stations. The Sector Operations Room at Kenley was badly damaged and had to be moved to an emergency room in a disused butchers in Caterham, while the airfield could only operate two of its normal three squadrons. An attack on Biggin Hill was fought off, while later in the afternoon Gosport, Ford and Thorney Island were all attacked. None of these last three were Fighter Command stations, reflecting once again the limits of the Luftwaffe's Intelligence branch. The attack on Gosport also saw the second aircraft type casualty of the battle (after the Defiant). During this raid the Ju 87s suffered such heavy loses that they were withdrawn from the battle and kept back for the planned invasion, when with Fighter Command out of the way their effectiveness would have been restored.

Between 8 and 18 August the Germans lost 367 aircraft (192 of them in the four days between 15 and 18 August), while Fighter Command lost 183 in combat and 30 on the ground. Just over 100 new fighters were produced in the same period, and the gap was filled by the repair units. The Command also lost 164 pilots killed, missing or seriously wounded, while only 63 new fighter pilots completed their training. This gap could not be filled as easily. On 17 August Bomber Command provided five volunteers from each of four Battle squadrons, and at about the same time Army Cooperation Command provided three pilots from each of five Lysander squadrons, for a total of 35 pilots. Pilots in the last stages of Bomber and Coastal Command training were quickly converted into fighter pilots. 18 August also saw No.310 (Czech) Squadron become operational, while No.312 (Czech) Squadron followed at the end of the month (No.303 (Polish) Squadron had been operational since late July).

If the weather had been better then 18 August would probably been seen as the start of the third phase of the battle, but for the next few days bad weather prevented any large scale raids, and so the third and most dangerous phase of the battle didn't really begin until 24 August (In his own report produced in September Park saw 19 August as marking the start of a new phase in the battle).

Phase 3 - 24 August-6 September: The Assault on Fighter Command

The third phase of the battle is generally seen as having started on 24 August. This saw the start of a period of better weather that allowed the Germans to fly an average of 1,000 sorties per day until 6 September, with peaks of over 1,600 sorties on 30 and 31 August. This period saw the Luftwaffe continue the policy first seen on 18 August of attacking RAF bases further inland, and was the period in which the Germans came closest to victory. In the earlier phase of the battle Tangmere was the only one of the crucial Sector Stations to be in a vulnerable position close to the coast, but the new German tactics saw the network of stations around London come under attack. The success of this phase of the German attack was partly accidental, in that they didn't know of the existence of the vital sector control rooms. If the control rooms had not been built at major fighter stations then this stage of the battle would have been rather less dangerous for the RAF, although the fighter stations and squadrons would still have come under severe pressure.

Although the first attack on the inland stations came on 18 August, bad weather prevented the Germans from returning in force until 24 August. This marked a period in which the Germans flew an average of 1,000 sorties per day, peaking at over 1,600 sorties on 30 and 31 August and lasting until 6 September. The gap saw two significant events. The first was a conference at Goering's palatial home at Karinhall on 19 August in which he repeated that the RAF was the Luftwaffe's main target. Enemy fighters were the first target, either in the air or on the ground, followed by the aircraft industry and the ground organisation of the bomber forces.

The second came on 20 August, when Churchill paid his famous tribute to the men of Fighter Command, remembered many for the line 'never in the field of Human conflict was so much owed by so many to so few'. What does still surprise is how early in the battle this speech was made - on 20 August the hardest part of the battle still laid in the future.

A key feature of this period of the battle was the repeated heavy attacks on the sector stations. North Weald was hit on 24 August, Biggin Hill twice on 30 August, Debden, Croydon, Biggin Hill and Hornchurch twice on 31 August. Biggin Hill was worst hit and the vital control room was knocked out of action. The staff moved to an emergency control room in an estate office in a nearby village, but this could only handle one of the three squadrons based at the airfield, so the remaining two were controlled from other sectors. 31 August also saw Fighter Command suffer its heaviest losses of the battle, with 38 aircraft shot down. The benefits of the RAF's 'home advantage' can be seen very clearly on this day. Of the 38 pilots shot nine were killed. Others will have been wounded and put out of action, but many were able to return almost immediately to the battle. In contrast very few of the crews of the 39 German aircraft lost on the same day will have escaped to fight again.

September started as August had ended. On 1 September Biggin Hill was hit for the sixth time in three days. Most of the buildings were now unsafe and most work had to take place outside, but the station somehow managed to keep working (largely due to the bravery of the WAAFs). Hornchurch was attacked on 2 September, North Weald on 3 September and Biggin Hill on 5 September. The aircraft industry also suffered. Vickers at Weybridge was hit on 4 September, Hawker on 6 September. The attacks also began to creep closer to London. On 5 September the oil farm at Thameshaven was hit and set on fire. The Germans returned on 6 September, and again during the raid on London on 7 September.

Perhaps the most dangerous aspect of this period of the battle was the slow but steady decrease in the quality of the British fighter pilots. As more experienced pilots were killed or wounded they had to be replaced with novices, many of whom would later become equally experienced, but that was in the future. The experienced squadrons were also becoming worn down, and under the Dowding system they were thus moved away from the battle and replaced with fresh squadrons. Unfortunately the intense nature of the battle in late August and early September meant that this policy failed. The inexperienced squadrons suffered much heavier losses than the tired units they were replacing, and in some cases had to be withdrawn themselves. On 8 September Dowding replaced the rotation system with a new 'Stabilization Scheme' (presumably because it was designed to stabilise the experienced squadrons). Fighter Command's squadrons were split into three categories. 'A' class categories were to be manned entirely with fully trained pilots and were to be used in No.11 Group and in the Middle Wallop and Duxford sectors of the neighbouring groups. Five 'B' class squadrons in No.10 and No.12 Groups were also to be kept up to strength and were to be used if an entire 'A' class squadron needed to be rested. The remaining squadrons, in every other group, became 'C' class squadrons. These had a core of five or six experienced pilots and were used to give new pilots enough experience to allow them to be moved to 'A' or 'B' class squadrons. At about the same time the number of pilots in each squadron was reduced from 26 to 16 - a move that in the short term allowed more squadrons to operate at full strength but at the price of eliminating each squadron's reserves, forcing just about every pilot to fly on every mission.

This period also saw an alarming trend in the number of fighters available to replace losses - the weeks ending 31 August and 7 September were the only two in the entire battle in which Spitfire and Hurricane losses greatly outnumbered the weekly output of new or repaired aircraft. Three more weeks at the same rate and Fighter Command might had run out of fighters, assuming it had enough pilots left.

Phase 4 - 7-30 September

7 September was one of the most important days in the entire Battle of Britain. After two weeks of attacks on its airfields No.11 Group was beginning to bend under the pressure, and another week of the same might have seen it snap. The vital sector stations had already been badly damaged and the men of the fighter squadrons themselves were operating under great pressure, knowing that they were not even safe on the ground. On the afternoon of 7 September yet another major German raid began to take shape, but much to the surprise and relief of the fighter squadrons the great attacking force bypassed them and made for London. The Germans had switched the focus of their efforts from Fighter Command to the British capital, a move that immediately reduced the pressure on Park's men and allowed them to begin to recover from the losses of 24 August-6 September.

There were two main motives behind this apparently idiotic decision. The best known of these is that a British attack Berlin so angered Hitler that he ordered the Luftwaffe to turn against London in a fit of rage - an early sign of Hitler's increasingly poor decision making. On the night of 24-25 August some German bombs fell accidently on London (Hitler had ordered the Luftwaffe not to attack the British capital without his express permission). In response Bomber Command managed to get 81 bombers over Berlin on the night of 25-26 August. The British bombers returned several times over the next few days. These raids probably didn't do much damage, but they were very embarrassing for both Hitler and Goering. On 4 September Hitler made a big speech threatening vengeance for the raids on Berlin and other German cities, and three days later the daylight attack on London began.

A less well known (but probably rather more important) motive for the change in plan was that by early September the Luftwaffe believed that Fighter Command was close to defeat. German intelligence greatly underestimated British fighter production, and overestimated the losses suffered by Fighter Command. With Fighter Command down to its last few reserves the attacks on the airfields had effectively achieved their aim and further attacks might not be so productive. The Luftwaffe was also frustrated by Park's policy of avoiding battle with their fighters as much as possible and concentrating on the bombers. What they wanted was to force the British into a single decisive battle, and it was believed that the best way to achieve that would be attack London, a move that would force Fighter Command to commit its last remaining reserves. A major attack on London was also expected to cause massive amounts of disruption, making the invasion that much easier.

In effect the Germans made the decision that saved Fighter Command because they believed they had already won and the invasion would take place in the next few days.
On 5 September the British intercepted a radio message ordering the Luftwaffe to carry out a massive raid on the London docks on the afternoon of 7 September. This allowed the civil defence organisation to quietly prepare for the attack, but on this occasion at least Ultra intelligence was not followed by victory in the skies. On the morning of 7 September the Luftwaffe attacked Hawkinge four times, suggesting that the attacks on the airfields would continue for some time. Park was thus slightly caught out when the main German attack developed in mid-afternoon. As No.11 Group's squadrons prepared to defend their airfields the Germans flew right past them - only four squadrons were able to attack them on their way in. Eventually twenty three squadrons were put in the air and twenty one made contact with the German formations, but with comparatively limited success - the Germans lost 41 aircraft, Fighter Command 25. One reason for the relatively low German losses was that they had developed a new formation, with the bombers protected by vast numbers of Bf 109s. Some provided the sort of high cover that the German fighter pilots preferred, but many more were used to provide the close escort, which was flew above, below, behind and to the sides of the bombers. This approach may have been unpopular with the fighter pilots, who found it too restrictive, but at least on 7 September it was very effective, making it difficult for Fighter Command to get at the bombers. As a result Woolwich, Thameshaven and the West Ham docks were very badly damaged in a major daylight raid for the first and only time. That night the German bombers returned, this time virtually unopposed and by the following morning 306 civilians had been killed and 1,337 seriously injured.

After the striking success on 7 September the weather prevented the Germans from returning on the following day. Large attacks took place on 9 September and 11 September, but without the success of 7 September. On 11 September Hitler was forced to postpone the date for the invasion from 21 to 24 September. This meant that another decision had to be made on 14 September, in order to give the German navy the ten days notice it required, but bizarrely Hitler chose to bring the invasion forward to 17 September. Once again German intelligence had overestimated the damage done to Fighter Command, and the major attack planned for 15 September was confidently expected to eliminate the few remaining fighters. This despite a week in which the Fighter Command had lost half as many Spitfires and Hurricanes as in the previous week (weeks ending 7th and 14th September), and had seen their reserves increase for the first time in three weeks.

After the battle 15 September was commemorated as 'Battle of Britain Day'. It was the day on which the RAF claimed the most victories, 185, although it was also the day on which the RAF over-claimed most dramatically, for the Germans actually lost 61 aircraft. This was still the third highest total they suffered on any day, but came as something of a disappointment when the German figures were discovered after the war. The real important of 15 September was that it made it clear that Fighter Command had not been defeated, and indeed was just as strong as at the start of the battle. On 17 September, the day on which the invasion was to have been launched, Hitler was forced to postpone it indefinitely.

The German attack on 15 September was not one of their best efforts. The massive formations took shape within radar range, and without any protective feints. Park was able to intercept the Germans as they crossed the coast, and their formations were under constant attack all the way to London. As a result they lost much of their shape, many bombs were jettisoned randomly to avoid attack, and limited damage was done. Goering ordered a second attack in the afternoon. This signal was intercepted and decoded and the news passed on to Dowding. This combined with a second well run radar interception to produce another successful defensive battle.

On 17 September the British had their first hints that the immediate threat of invasion was gone. Ultra intercepted a message ordering the air loading equipment for troop carrying aircraft on Dutch airfields to be dismantled. Photographic evidence came on 23 September when PR aircraft visited the invasion coast and found that the number of invasion barges between Flushing and Boulogne had gone down by one third, while a number of German destroyers had left the invasion ports for safer waters at Brest.

In the second half of September German tactics changed once again. There was still two major daylight raids, on 27 September and 30 September, but neither was successful, and the attack on 30 September was the last large scale daylight raid on London. The night time raids continued, while during daylight hours the Germans began to carry out a large number of fighter-bomber raids.

Phase 5 - 1-31 October

The final stage of the Battle of Britain saw the Germans abandon large scale daylight raids. Instead they focused on small-scale low level raids by Ju 88s and high-level fighter bomber raids, using bomb-carrying Bf 109s supported by pure fighters. The Bf 110 was also used as a fighter bomber during this phase of the battle. The main German bomber force was now used almost exclusively at night. Some of the daylight raids were on a very large scale, with up to 1,000 sorties on the busiest days, and the new German tactics posed a very serious challenge to Fighter Command. The fighter bombers were very hard to intercept, and losses on both sides fell significantly. Even so Fighter Command still lost 144 aircraft during the month.

In Britain the battle officially ended on 31 October. This day saw no aircraft lost on either side, and thus does mark a suitable stopping point. Of course the fighting didn't end, and the night bombing campaign, the Blitz, continued on across the winter of 1940-41 only ended when the Luftwaffe moved east in preparation for the attack on the Soviet Union, but the daylight battle was now at an end.