Air Fronts: Theaters of Operation - ETO -  AP 156: Battle of Britain - 6. The Battle of London

THE BATTLE OF BRITAIN. Air Ministry Pamphlet 156; Issued by the Department of the Air Member for Training, August 1943

THE BATTLE

VI. The Battle of London
24 AUGUST - 27 SEPTEMBER

To understand why the German air attack was suddenly switched in early September to London, and why it took the form of a day and night Blitzkrieg, it is necessary to realize that it was probably intended to be the climax of the Luftwaffe's efforts in the general invasion scheme.

German Preparations for Invasion

In the first few days of September everything pointed to the fact that the German preparations for the immediate invasion of this country were, if not finally complete, in a very advanced state. In the course of a speech on 4 September, Hitler had addressed a few words to the British people - 'calm yourselves' he had told them, `we shall come', and had promised also that, as a preliminary, their cities would be razed to the ground.

In the first week in September it was discovered that 160 German long-range bombers had been recently transferred from Norway to Belgium, and Ju.87 dive-bombers moved to forward positions on the Cherbourg peninsula. On the 7th the Blitzkrieg on London started with a savage and concentrated daylight attack on dockland, and the Germans announced that Goering himself had taken personal charge of the air operations. The same day photographic reconnaissance revealed the presence in the `invasion' ports of France and the Low Countries of over 800 self-propelled barges, which were being moved rapidly westwards into the forward ports from Dunkirk to Le Havre. This seemed to indicate an early attempt to cross the Channel —otherwise the barges and merchant ships would not, presumably, have been moved to bases which were so exposed to air attack. By the 9th the liners Bremen and Europa and three merchant vessels of 10-20,000 tons had arrived at Bremerhafen from Hamburg, and could have put to sea quickly. The state of weather and tides in the Channel at this period would also have been favourable for an actual invasion attempt. On 11 September the Prime Minister himself considered it necessary to give Parliament and the nation a solemn warning about the German plans: `No one should blind himself' he said `to the fact that a heavy, full-scale invasion of this island is being prepared with all the usual German thoroughness and method, and that it may be launched at any time now upon England, upon Scotland, upon Ireland, or upon all three.' By 13 September the number of barges in North French, Dutch and Belgian ports had increased to 1,700, and a little later rose to 2,500-the main concentrations being at Antwerp, Ostend, Flushing, Calais and Boulogne. The stage for invasion had been set.

Object of Attack on London

It is against this background that the Blitzkrieg on London should be viewed. Nor should it be forgotten that the attack on London did not immediately follow the air battle over the Channel and South coast - it had been carefully prepared by intensive operations spread over a fortnight and designed to clear the approaches to the capital. Various suggestions have been put forward to account for this savage and prolonged assault on London. The Germans said two things about it: first, that the night raids were acts of military reprisal for our attacks on Berlin; second, that the `scatter-bombing' into which many of the night raids degenerated was meant to intimidate the British public into a change of government. The first assertion was meaningless, and the second, as events were to show, was misguided. Another calculation which the Germans may well have made without advertising it, was that the attack on London would provoke a public demand for retaliation on Berlin which would have had the effect of diverting some of our bombing effort away from the barges in the Channel ports. It is interesting to record that this demand actually arose - but our bombing policy remained unchanged. It was also thought that the raids on London would have great propaganda value - they were no doubt meant to undermine confidence in America, to distract attention from the Luftwaffe's failure to achieve air superiority and to hearten the German people. All these may well have been contributory causes of the London Blitz  - there is more reason, however, to suppose that the primary German target in the night attacks on the capital was not the docks, oil storage tanks, industries or hospitals, which were all heavily damaged, but London's system of communications. It is likely that the Germans intended to prevent all passenger traffic to and from London in the hope that the life of the capital would be brought to a stop, and also to cut all communications with the North and South, with the object of isolating the whole of the South-East of England. Once that had been done the invasion would probably have followed. It, therefore, seems likely that the attacks on London were not just another stage of the air battle, but the prelude to an expected land battle.

Clearing the Approaches to the Capital (24 August - 6 September)

The weather on 22 and 23 August had not been good, but with clearer conditions on the 24th the Luftwaffe resumed the intensive operations which had been broken off after the 18th. During the next fortnight the air effort was concentrated on airfields to the North and South of London and on targets in the Thames Estuary. Except on the 27th, large numbers of German aircraft were used, and this kept our fighter squadrons fully employed. Fortunately several new squadrons became operational about this time, including the two Polish squadrons, the first of the Czech squadrons, and a Royal Canadian Air Force squadron flying Canadian-built Hurricanes. Every effort was made by the enemy to deceive the defenders by feint attacks on convoys, by geographical diversions, particularly against Portsmouth, and by splitting up the large formations in different directions not long after the coast had been crossed. Considerable interest was shown in the Dover balloon barrage, which was attacked on five occasions, and the first deliberate daylight attacks on non-military objectives were also made at this period. Nothing, however, could conceal the fact that the enemy was making a supreme effort to put out of action the fighter airfields covering the approaches to London, and particularly those which guarded the Thames Estuary. The enemy succeeded in doing heavy damage on these airfields, but he did not cause them to be abandoned. From 1 September onwards airfields, industrial targets and oil storage depots in the Thames Estuary were attacked regularly both by day and by night. The particular interest in clearing the approaches over the Estuary was probably connected with the deteriorating weather conditions. On days of low or scattered cloud, when it was not justifiable to use large numbers, nuisance raids could be made by smaller numbers, but even these would have difficulty in reaching London unless they felt free to follow the course of the river. The object was, when once the intensive attacks on London had begun, to keep the capital, so far as possible, under a continuous alert.

Intensified Attacks on Airfields

From 24 to 26 August the Luftwaffe worked to an identical plan of operations, carrying out a series of attacks on Kent and the Thames Estuary in the morning and afternoon, the last attack being timed to coincide with a heavy thrust on the Portsmouth-Portland area and with lighter attacks in the extreme South-West. On 24 August four heavy attacks were made on Manston airfield which, despite much damage and serious fires, remained serviceable by day. Hornchurch and North Weald airfields were also attacked. Warmwell was bombed on the 25th, one hangar and several buildings being damaged, and Debden was attacked on the following day, when two hangars were damaged and a barrack block and transmitting aerial were destroyed. Generally speaking, however, most of these attacks were intercepted early and several enemy formations were turned back before reaching their objective and forced to jettison their bombs in the sea or in comparatively open country. Night attacks were intensified and focused mainly on industrial targets in Birmingham and Coventry, though the first enemy bombs to fall in Central London were dropped on the night of 24-25 August.

From 28 August to 6 September the enemy confined his attention to the airfields protecting London, and to industrial targets and aircraft factories along the Thames Estuary. The heaviest attacks occurred on 30 and 31 August and on 3 September. Again the number of successful interceptions was high except on the 6th, when a thick haze over Kent and the Thames Estuary prevented our fighter squadrons from intercepting enemy aircraft which came in lower than usual. It was inevitable that under the continuous enemy pressure our fighter squadrons should occasionally be caught on the ground, and the cases of three aircraft surprised while taking off at Hornchurch on 31 August, and one squadron attacked while refuelling at North Weald on 3 September, may be mentioned as exceptional and not typical instances.* Between 24 August and 6 September airfields which were most frequently attacked were Biggin Hill and Hornchurch (both seven times), Eastchurch (six times), Detling, Hawkinge and Manston (five times), and North Weald, Debden and Lympne.**

Results of Attacks on Airfields

The object of these attacks on our airfields was to render them unserviceable, to force the abandonment of the more important sector stations, and thus not only to uncover the approaches to London, but also to imperil the operational control of fighter squadrons which were dispersed on satellites. Owing to early interception by our fighters, to the stout defence of the A.A. posts, and to the enemy's forced adoption of high-level pattern bombing, the attacks could not often be pressed home, and it was very rarely that the most vulnerable targets on airfields could be identified and bombed. Even though attacks were heavy and frequent, the damage done to airfields could be repaired sufficiently quickly for them not to remain unserviceable for long. Crater damage to the surface of landing grounds was perhaps the least of the difficulties to overcome, since even when large numbers of craters had been made it was only necessary to fill in a few in order to have a couple of runways usable. A good deal of temporary inconvenience and discomfort was caused by the destruction of administrative buildings, stores and can-teens, but this did not prevent airfields being used. Damage to purely internal communications on airfields was usually quickly repairable by the Royal Corps of Signals. The most difficult problem arose when the landline communications, particularly of fighter sector stations, were put out of action. This usually occurred when hits were obtained on operations rooms, as happened at Biggin Hill. Where emergency operations rooms were not already available they could, however, be quickly improvised, and G.P.O. repair detachments were able to restore the essential communications without delay. Direct hits on such important nerve-centres were, however, infrequent and on at least one occasion - at North Weald - on 3 September, an operations room received a direct hit on the roof without any damage being done. Finally, aircraft could be destroyed on the ground, but losses in this way were minimized by the practice of dispersal  to satellite airfields. Of the total number of aircraft in Fighter Command destroyed by enemy action, including those missing, only just over 7 per cent. were the result of bombing. Casualties to personnel were slight except where direct hits were obtained on shelter trenches as happened at Kenley and Biggin Hill.

Repair of Airfields

To illustrate the speed with which airfields could be brought back into commission after heavy attacks, a few typical but earlier examples will suffice. Eastchurch airfield was accurately bombed early on 13 August by 40 Dornier 215, with a large fighter escort. Much damage was done to buildings; 50 craters were made on the landing ground, which had no concrete runways, and the operations room and telephone communications were put completely out of action. Immediately the `all clear' had been sounded ground personnel and a R.E. detachment went to work on the craters, and the result was that the airfield was never out of action for day flying. A despatch rider was sent off to Sheerness at 0800 hours, the Post Office repair parties arrived about two hours later, and by twelve noon the essential telephone lines were all working. An emergency operations room was fitted up in an underground shelter and its communications and facilities, including teleprinter service, were installed by the G.P.O. authorities in about two days. Water mains and electrical cables had also been badly damaged. Temporary repairs were immediately effected to give an emergency supply and permanent repairs were completed by the afternoon of 15th. This work was carried out by men of a Works Repair Depot. Detling airfield was also attacked on 13 August, the operations room, the sergeants' mess and officers' mess and the airmen's cook-house all being destroyed. Here the essential services, including communications, were working by noon of the following day. Extensive crater damage was done to Driffield airfield on 15 August. Fifty-four bombs had been dropped, and some of the craters measured 30 feet in diameter by 10 feet in depth. There were also unexploded bombs to be dealt with. The attacks had ended about 1420 hours; by 1600 hours the nearest Works Repair Depot had been informed of what men and materials would be required to effect repairs, and by 1650 hours a working party was on its way. Royal Engineers and 200 soldiers were called in to help and work continued till dark. Aircraft took off from the airfield on the morning of 16th, and by 1700 hours of the same day all the craters had been filled in. At Kenley on 18 August the landline communications were cut and much other damage done. The emergency operations room was taken into use, and within 2 1/2 days 90 per cent. of the communications facilities had been restored by the G.P.O. working `round the clock'. At Biggin Hill at the end of August a `stand-by' operations room was available near by, and thus operational control over dispersed squadrons was never lost.

It may, therefore, be said that on these and similar occasions when airfields were the main target, the Battle of Britain was won very largely because of the foresight and skill of the station commanders in organizing their personnel and utilizing the local facilities for repairs work, the unremitting labours of the Works Repair Depots, and the indispensable assistance rendered by the G.P.O. communications staff, the Royal Engineers, and the Royal Corps of Signals. Nor should we forget the devotion to duty of the male and female ground staffs on the airfields who carried on during and after enemy attacks.

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* For an eye-witness account of the attack on Hornchurch, see R. Hillary, The Last Enemy, pp. 124-8.
** Eastchurch was a Coastal Command airfield.
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The London Blitzkrieg (7 September-27 September)

Except for two smallish raids on Southampton on 24 September, an attack on Bristol on the 25th and two further attacks on Southampton on the 26th, the Luftwaffe devoted practically the whole of its resources during this period to a Blitzkrieg on London. Attacks on our airfields in Kent continued, but they were mainly carried out by night, and the few day attacks were made from such high altitudes that they were usually ineffective. Convoys were bombed, but only spasmodically, and even these attacks were mostly feints to cover larger scale operations directed on the capital.* Besides being concentrated on London, the attacks were now carried out by night as well as by day, and for the Germans' immediate purpose the night operations may be said to have been more important. Confirmation of this, especially for the last half of September, was given by the announcements of the German High Command which, at that time, referred to the day operations as `armed reconnaissances', and the night raids as `reprisal attacks'. An exception must, however, be made of the extensive and decisive air battles of the 7th, 15th and 27th. With Goering in personal command of the offensive the situation was not without a tinge of irony, seeing that the C.-in-C. of the Luftwaffe had been the consistent advocate of the necessity of obtaining air superiority by day. Obviously, therefore, this policy had not been freely chosen by the enemy, but had been forced upon them by the successful defence put up by Fighter Command. The general object of the German High Command was to do as much damage as possible in London by night - especially to vital rail communications - and to disorganize the life of the capital by day by keeping it under continuous `alert'. Three attempts were made to break through to Central London by massive air attacks by day, but only on the 7th was this policy successful. The German effort was, however, continuous, for even on days of comparatively unfavourable weather conditions aircraft were sent over to carry out nuisance raids using cloud cover. The broad plan of campaign was thus to demolish London by night and prevent it recuperating by day. London was in this way besieged from the air and had to rely mostly for its survival on its own steady morale under heavy air bombardment and on the efficiency of its Civil Defence Workers.

At this time three problems weighed heavily upon the C.-in-C. Fighter Command and upon the A.O.C. of No. 11 Group. The first was the increasing difficulty of making interception owing to the autumn cloud conditions and the new high-flying technique of the enemy, the second was to find an answer to the new tactics which were employed by the enemy for the attacks on London, and the third was the pressing need for relieving the strain on the fighter squadrons which had been continuously engaged in the air fighting since the beginning of the battle. The first problem was technical, the second tactical, and the last administrative; and unless satisfactory solutions had been found to all three the air defence of London would have been seriously weakened.

The Problem of Information

From the middle of September onwards the Observer Corps, which was responsible for reporting the movements of enemy aircraft once they had crossed the coast, began to experience considerable difficulty in their work because of the greater prevalence of .cloud conditions, because enemy aircraft were flying at much greater heights and because the proportion of enemy fighters was increased. In these conditions the Observer Corps was not always able to decide whether the enemy aircraft were fighters or bombers, and occasionally missed them entirely. This defect in the warning system was remedied by the use of single Spitfires on special fighter reconnaissance duties which were instructed to patrol at high altitudes and to report on the movements of incoming enemy formations by R/T. This experiment worked very successfully, and on several occasions enemy aircraft flying high above the clouds were located and shadowed and vital warnings passed to sector controllers. As September went by there was also a temporary falling off in the reliability of radio location warnings, and this necessitated the withdrawal of fighter squadrons from the forward coastal airfields to bases further back from which they were better able to attain the requisite height before intercepting. From 21 September onwards a series of day patrol lines was introduced between London and the Kentish coast. Squadrons were detailed to patrol these lines at heights sufficient to allow them to intercept enemy aircraft which had split off from the main formations.

The Tactical Problem

During the September operations against London the enemy attempted to divert our fighter patrols from attacking his bombers by the use of high fighter screens. Bomber formations too operated at greater heights - from 16,000 to 20,000 feet - and were sent over on a much wider front than previously and in two or three waves. Often the large formations split up when fighter opposition was met into small raids which went on to Central London, if necessary without fighter escort. From a quarter to three-quarters of an hour before the main bomber formations appeared, however, the enemy sent up a high fighter screen over Kent to attract up our fighters and exhaust their petrol before the main attack developed. The time which elapsed between the arrival of the high fighter screen and of the bombers with their close fighter escort was varied in order to confuse the defences - sometimes the interval was only a matter of a few minutes. The escorting fighters were generally divided into two parts - some operating in close contact with the bombers and others a few hundred yards away and a little above. Close cover was provided above, behind (at a lower level), and on both sides of the bombers. If the formation was attacked from starboard, the starboard section engaged our attacking fighters, the top section moved to starboard and the port section to the top position; if the attack came from the port side then the sections moved to port in the same way. Our fighters attacking from the rear were engaged by the rear section and the two outside sections similarly moved to the rear. If the attack came from above the top section went into action, while the side sections gained height in order to be able to follow our fighters down as they broke away. If attacked themselves all the sections went into defensive circles.

These were skilful tactics and were hard to counter; it is not surprising that small numbers of bombers from time to time slipped through our defences to the capital. Nevertheless the A.O.C. of No. 11 Fighter Group, Air Vice-Marshal Park, must be credited with having evolved a system of counter tactical moves which provided an adequate daylight defence for London. The reply was to redispose and concentrate our Spitfire squadrons and to give them the responsible task of engaging the enemy high fighter screen half-way between the coast and London. This left some of the Hurricane squadrons free to deal with the bomber formations and their close escorts before they reached the outer ring of London's fighter airfields to the East and South. The rest of our fighter squadrons were used as an inner defensive screen to attack the third wave of enemy formations and also to mop-up enemy aircraft as they retreated from London. In actual operation this system resulted in a certain amount of specialization by the different fighter groups. On days of intensive air fighting the task of engaging the maximum number of enemy aircraft before they reached London fell to No. 11 Group. Enemy bombers which broke away from the main formations, hoping to attack even without escort, were often met by several squadrons from No. 10 Group which was called upon to provide the close protection of aircraft factories and airfields. Lastly, No. 12 Group was very successful in attacking the retreating enemy bomber formations, which had often been separated from their escort or broken up by the A.A. defences. The daytime defence of London was thus the result of close co-operation between the various fighter groups, so far as operational control was concerned, and of excellent teamwork on the part of the fighter pilots in actual combat.

By the beginning of September a further serious problem was the need not only to relieve the original fighter squadrons which had been in action since the beginning of August, but also to replace some of the squadrons which had been brought into the line at a later period as the intensity of the air fighting developed. Although normally a fighter squadron would remain in the line from a month to six weeks, some of the units had to be replaced on account of losses after a week or ten days. Squadrons actively engaged in the defence of London found that they had no time to complete the training of new pilots who came to them from the Flying Training Schools via the O.T.Us and the previous system of relieving two or three squadrons a week could no longer be continued. It was to meet this situation that the C.-in-C. Fighter Command devised the system of A, B and C Squadrons already referred to on page 15. There can be no doubt that this experiment tided over a period when the strain on our fighter pilots was proving severe, and enabled Fighter Command to meet the new drain upon its resources of personnel at the most crucial stage of the battle.**

Mass Daylight Attack on London

The attempt to vanquish London by a knockout blow was launched on the evening of Saturday, 7 September. This was the `historic hour' spoken of by Goering when he told the German people how the Luftwaffe had `for the first time delivered its stroke right into the enemy's heart'. The attack proved to be the biggest single attack so far delivered and was directed on the docks and oil storage depots of East London and the Thames Estuary. It took place between 1630 and 1830 hours and nearly 400 aircraft were employed. The attack was in two waves - the first at 1630 hours flying direct to the Estuary being followed about an hour later by more aircraft which went over Central London, turned round and returned over the East End and the Estuary. It was obvious that the attacks were regarded by the Germans as being of special importance, for very strong fighter escorts were provided, while the bomber formations included a large number of the heavier Do.215, eighteen of which were shot down. It was also noticed that besides flying higher than usual - at heights between 15,000 and 20,000 feet - the enemy bombers made determined efforts to maintain their formations in spite of losses by fighter attack and intense A.A. fire. The attacks were pressed home and bombs were dropped on Woolwich Arsenal, the docks at Millwall, Limehouse, Rotherhithe and Tower Bridge and also on the Surrey Docks, on the oil storage tanks at Thames Haven and West Ham power station. Silvertown was described as `a raging inferno'. These attacks were at once reported with glee in the form of running commentaries from all the German radio stations. Great destruction was done in the East End of London - the docks were ablaze along both banks of the river for miles and served to light the German night bombers to the target a few hours later.

This, however, should be remembered - that 7 September was the only occasion when London had to suffer massive air bombardment by day. The losses inflicted on the enemy were so serious that the German High Command itself made the admission that the attack had been paid for by `heavy sacrifices', and although tried again, the attempt to bomb London to pieces by daylight never succeeded. The most successful of the fighter squadrons operating on that day was Polish - the Kosciuszko Squadron - which destroyed 14 enemy aircraft. This result, how-ever, was rendered possible by good teamwork on the part of other squadrons. One incident of the air fighting illustrates this point. When the Poles arrived on the scene of the battle they met about 40 Do.215 bombers flying at 20,000 feet. Some distance behind and above was a small formation of Messerschmitt 110. Farther behind still, and at an even greater height - almost 30,000 feet - were Me.109. The initial attacks on these formations were made by a Spitfire squadron which took on the high-flying Me.109 and by a Hurricane squadron which attacked the rear of the bomber formation forcing it to turn back and thus providing the Polish squadron with a first-class target. The Poles, who had been flying in sections of three one behind the other, swung round so that the whole squadron was almost broadside on to the bombers. They dived 4,000 feet out of the sun, each pilot selecting his own victim. ` We just gave them all we'd got' said the Squadron Leader `opening fire at nearly 450 yards range and only breaking away when we could see the enemy completely filling our gun sight. That means we finished the attack at point-blank range. We went in practically in one straight line, all of us blazing away.' These and other methods resulted in the Germans losing nearly a quarter of their attacking force on that occasion.***

Night Attacks

The attack made the same night was equally severe, and was carried out by about 250 bombers, which were guided to their targets by the dockside fires. Nine conflagrations and many other large fires were caused, thousands of houses in the East End of London and some factories were destroyed and three of the main line terminal stations were put out of action.**** During the three following nights - from Sunday the 8th to Tuesday the 11th - the destruction continued. As the result of Sunday night's attack twelve conflagrations were started in the Docks and the City and every railway line from London to the South was put out of action. On Monday the enemy took to indiscriminate or ` scatterbombing' - hoping to undermine the population's morale. On Tuesday night railway stations again appeared to be special targets for the 150 aircraft which operaed. By this time the Germans had worked out a technique for the night attacks on London. Aircraft came over in small waves at intervals and flew along clearly defined corridors of approach, using different routes for the return journey. On the 10th the first wave flew in over the South coast and out over Essex; the second wave approached from the East and returned over Hastings, where it was met by the third wave crossing the coast on its way to London. Usually large numbers of incendiaries were dropped in the early attacks to light up the target for later aircraft, which unloaded H.E. bombs. On Wednesday night - 11-12 September - the inhabitants of London received a tonic when the capital's anti-aircraft barrage went into full action - the number of A.A. guns having been doubled since the 7th.***** The guns of the Inner Artillery Zone fired 13,500 rounds during the night. It was estimated that this barrage prevented a third of the attacking aircraft from dropping bombs in Central London. The damage to London's vital key points - railways, factories and public utilities - was greatly reduced, and the number of large fires was also lessened..

September 15 and its Significance

Meanwhile the day attacks had been kept up, but during the latter half of the week bad weather had restricted the scale of the operations. On Friday the 13th, a day of intermittent rain and low cloud, the enemy adopted his night-time tactics of sending over small numbers of aircraft in waves and succeeded in giving Central London its longest daylight alert from 0945 to 1355 hours, while bombs were dropped in Downing Street, on the Royal Chelsea Hospital, and according to the German communiqué on `oil installations' at Buckingham Palace. After two large attacks on the 14th, which took the form of fighter sweeps by Me.109, the Luftwaffe made on the 15th what will probably be always remembered as its greatest concentrated effort to destroy Fighter Command at this crucial stage of the operations. The air fighting which took place on that day has been brilliantly described in the official pamphlet on the Battle of Britain, and the reader is, therefore, referred to that account as the best that is yet available. In one sense 15 September may well be regarded as epitomizing the whole of the great struggle which lasted from July to October. For those who like coincidences it is interesting to remember that this fighting took place like the battle of Waterloo, on a Sunday. The result of 15 September 1940 was, however, not so immediately obvious as that of 18 June 1815, and its effect on the general course of the present war may be compared more aptly with that exerted on the Napoleonic wars by Trafalgar. The Prime Minister on 17 September spoke of the action as `the most brilliant and fruitful of any fought upon a large scale up to that date by the fighters of the Royal Air Force', and drew the conclusion that after the grievous inroads which had recently been made upon the enemy's superiority of numbers, the country could `await the decision of this prolonged air battle with sober but increasing confidence'. The impression it made in the United States was, however, immediate and profound, and it was from this time onwards that Americans became convinced that the R.A.F. would be the final victor in the battle.* ***** September 15 was one of the decisive battles of the war, not merely because the enemy lost more aircraft on that day than on any other during the battle, but also because it was a staggering defeat inflicted on the Luftwaffe, at a time when the German High Command was preparing to invade this country.

On 18 August, as already noted, the strain on the organization of Fighter Command had been prolonged; both on 18 and 27 September the enemy effort against this country was greater and on no less than sixteen other days a greater number of sorties was despatched by Fighter Command to intercept enemy air-craft. This, however, does not in any way detract from the vital significance of 15 September as the day which saw the Luftwaffe's greatest defeat. The day was notable for the high proportion of interceptions which were made. In the first action - from 1100 to 1230 hours - twenty-four squadrons operated, of which all except two engaged the enemy; in the second - from 1400 to 1530 hours - twenty-nine squadrons were despatched and only one failed to intercept and engage. In all twenty-nine squadrons operated during the day, twenty-five of them twice;** ***** and twenty-five squadrons engaged the enemy, twenty-three of them twice; while one squadron (No. 66) was in action three times. This day was decisive in another sense also, in so far as it began a new phase of the air fighting in which the Germans began to experiment with large-scale fighter sweeps. These, as time eventually showed, formed the transition to the final or fighter-bomber stage of the air battles. September 15 may or may not have decided the Germans against the immediate invasion of this country, but it did mark the beginning of the end of the Battle of Britain.

September 16 to 26

From 16 to 26 September both the nature and the scale of the operations against this country underwent a change. The scale of attack was reduced, the concentration on the capital was less marked and less was seen of the enemy's long-range bombers. September 16, as might have been expected, was not a day of great activity, most of the raids being by single aircraft and few of them reached London. One small formation flew over Bristol and spent most of its time machine-gunning cows and a balloon near Hempton, North of Filton. Other activities of this kind included a low-flying machine-gun attack on streets in the Hackney district on 19 September. The 21st was devoted almost entirely to reconnaissance flights carried out by aircraft operating singly or in pairs. Practically the whole coastline of the country was covered and particular attention was paid to the South-West. The most considerable operations at this time took the form of extensive fighter sweeps at great altitudes, during which continuous patrols were usually maintained off the Dutch and Belgian coasts and in the Straits of Dover. Enemy fighters, which were mostly Me.109, operated in this way on the 17th, 18th, 20th and 23rd. The 18th was an exceptional day in this phase - no less than 500 fighters and 240 bombers being sent over to make three major attacks on Kent and the Thames Estuary. In the third attack a few four-engined aircraft are reported to have operated. In all three attacks most of the aircraft flew at 25,000 feet or over. Little damage was done except to oil storage tanks at Port Victoria.

The enemy long-range bombers re-appeared in greater strength on 24 September, and on that and the two following days were employed in attacks on Southampton and Bristol. The operations carried out during this short spell of activity were, however, to be the last of any significance by long-range bombers by day during the Battle of Britain.*** ***** The attack on Filton airfield and on the Bristol aircraft factory on the 25th was heavy. The reports of the types and numbers of enemy aircraft engaged were conflicting, but it is probable that the formations consisted of two or three Gruppen (wings) of 27 bombers each, in wedge formation with a close escort of 30-40 Me.110. The enemy made one run over the target and all the bombs were released simultaneously, falling short of, upon and beyond the works. The damage to the aircraft factory was serious. Three squadrons and one flight of our fighters engaged the enemy aircraft, of which 18 were destroyed. Three were also shot down by A.A. fire. Two evening attacks were made on Southampton on 26 September, the first of which concentrated on the Supermarine works, and the second on public utilities.

Last Day of Intensive Air Fighting

Friday, 27 September, was the last of the `great days' which may be said to have marked the progress and determined the course of the Battle of Britain. Visibility was poor at first in Southern England, but the weather improved later, except in certain areas affected by intermittent rain. A record number of enemy aircraft - 850 - operated against this country, and four major attacks developed, three over Kent directed on London, and the fourth against Filton. During the first attack over South-East England about 180 enemy aircraft operated, crossing the coast at Dungeness in several waves. Only about a third of the enemy aircraft penetrated a line drawn from Maidstone to Tonbridge, and few reached Central London. Fourteen of our fighter squadrons were despatched, and all engaged the enemy. In the second attack, also on Kent, about three hundred enemy aircraft were involved. Many of these remained behind on the coast of Kent, but a large wave of about 200 operated over the Thames Estuary at Chatham and heavily bombed Maidstone on their return. Eighteen of our squadrons were despatched, and again all engaged the enemy. The third major attack on Kent followed in the afternoon, when about 160 aircraft were employed. Two large formations flew to Maidstone and Biggin Hill, and about 20 aircraft reached the London area. Other raids spread out fanwise over Kent. Only one of the 13 squadrons despatched to intercept failed to do so. The attack on Filton was made by about 75 enemy aircraft operating from Cherbourg. When flying over Frome a split from the raid turned back, and a further split broke off later to the North-West, probably acting as a diversion. The main formation, which appears to have consisted of about 30 He.111, escorted by an equal number of Me.110, attacked Filton from 15,000 feet, dropping eight bombs, two of which fell close to the operations room. The serviceability of the airfield was not affected. All of the five squadrons despatched engaged the enemy aircraft, of which they destroyed ten. A.A. fire shot down another two.

During the day 28 of our squadrons operated and all engaged the enemy. Six of these squadrons were in action three times, and nine others intercepted twice. This was the last of the great daylight attacks on London, and its failure set the seal on the failure of the German Air Force to prepare the way for invasion. After 27 September the enemy long-range bombers were employed in smaller numbers, and during October - which was to be called Messerschmitt month - the enemy relied almost entirely upon his fighters and fighter-bombers. Whenever, in future, the German long-range bombers were used they were accompanied by four or five times their number of fighters. It only remains to point out that 27 September also saw the signing by Germany, Italy and Japan of a ten-year pact which was directed against the possible intervention in the war of both the United States and Russia. Whatever the ultimate significance of this agreement, it could have only one possible immediate meaning, and that was that Germany had given up all hope of victory in 1940. It was an acknowledgment in diplomatic terms of the triumph of the R.A.F.

Bombing Attacks on Invasion Targets

The invasion threat had, however, not been met and defeated by Fighter Command alone; it had also been warded off by offensive action on the part of Bomber and Coastal Commands. Ever since 7 September, when the enemy invasion barges had been observed massing in the Channel ports, our medium and heavy bombers had attacked them by night and by day. The attacks commenced on the night of 7-8 September when Calais, Dunkirk, Ostend and other targets were bombed. Throughout September Blenheims pressed home the attacks by day whenever cloud conditions permitted, and Wellingtons, Whitleys, Hampdens and Battles operated by night. Swordfish and Albacore aircraft of the Fleet Air Arm, operating under Coastal Command, also took part. In the first attack on Ostend, one Hampden claimed eight direct hits among 60 large barges. Other particularly successful raids on invasion targets were made on the nights of 8th-9th at Calais, Dunkirk, Ostend, Boulogne, Bremen and Hamburg, and on the night of 11th-12th at Calais, Ostend and Flushing. The heaviest scale of attack during September was on the night of 20th-21st, when 150 bombers operated. The gun emplacements at Cape Gris Nez, railway centres at Brussels and in the Ruhr, and enemy airfields in occupied territory, may also be classified as invasion targets which were heavily attacked at this time. Even Goering himself was not forgotten, for on the night of 14-15 September a direct hit was scored on the Chateau d'Argenteuil, North-West of Paris, which was believed to have been his Headquarters. It was on the following night that Sergeant John Hannah, the 18-year old wireless operator and air gunner, won his V.C. for heroism in extinguishing the flames in the cockpit of a Hampden bomber which had attacked Antwerp.

During September no less than 60 per cent. of our bombing effort was directed against the enemy's invasion ports, on which about 1,400 tons of bombs were dropped. The remaining effort was concentrated against rail communications, shipyards and oil targets in Germany and occupied Europe. Between 7 September and the end of the month Calais was attacked every night except two, and Boulogne every night except three. During the same period Dunkirk was bombed on 18 nights and 38 attacks were made on Ostend. Flushing, Antwerp, le Havre and the ports of North-West Germany were also regularly visited. Many fires were started among docks, warehouses and oil storage depots, and many barges were sent to the bottom. This was at least one of the reasons why the Armada of 1940 never put to sea.

Reasons for Failure of German Night Attacks

The Blitzkrieg on London in September which the Germans intended to mark the climax of their preparations for invasion had thus failed to achieve its object. Something has already been said to explain how the daylight attacks on the capital were defeated; it remains only to indicate briefly the reasons for the failure of the night attacks. One fact in the situation which undoubtedly helped London to weather the storm was its own immense size, which meant not only that vital targets were dispersed, but also that the physical destruction of London acre by acre was impossible. The systematic destruction of London by night on the scale of effort which was employed by the Germans at that time would have taken years to complete. The enemy also made the task more difficult for himself by resorting to `scatter-bombing', which prevented heavy concentrated attacks being made and failed completely to terrorize the population. It was also a piece of bad psychology on the part of the Germans, for by spreading the damage among all sections of the city it tended to equalize the suffering and loss sustained by all classes of the community which were, as a result, linked more closely together. Thus, far from lowering, scatter-bombing actually helped to raise morale. Nor were the civilian casualties incurred during the Blitz as high as had at first been expected - during September civilian casualties for the whole country amounted to 6,954 killed and 10,615 seriously injured - the majority of these being in London. As the Prime Minister pointed out at the time, the casualties per ton of bombs dropped were lower than those of the first world war. Heavier losses had been prevented by the building of shelters and the emergency use of the underground tube stations.

In the actual defence of the capital by night our ground defences were undoubtedly the most effective factor. Many vital targets in London were saved from heavy air bombardment by the intensity and accuracy of the A.A. guns, and it had been the barrage of the Inner Artillery Zone which had, to some extent, obliged the enemy to resort to indiscriminate attacks. Night fighter squadrons did operate over London, but without much success in destroying enemy bombers. The main reason for this was the difficulty of interception at night. Our aircraft still relied mainly upon the illumination of enemy aircraft by searchlights. These, however, were dependent, during most of the Battle of Britain, upon sound locators for the direction of their beam, and owing to the increased height and speed of the enemy bombers, this method was becoming unreliable. Alternative methods of interception were being developed. Another factor was the comparatively low speed of the Blenheim, which was the aircraft principally used for night fighting at this time. Owing to its slow speed the Blenheim could not overtake the German night bombers except through surprise. Defiants were also employed for night fighting after being withdrawn from the day fighting, but it was not until October that the faster Beaufighters began to replace the Blenheims in the night operations.**** *****

One surprising feature of the night attacks on the capital was the fact that the Germans discontinued their heavy attacks upon its vital rail communications. Much damage had been done to these targets, and the reason for giving up the attacks is not at all clear. It is possible that owing to the defects of their night flying training the Germans found it difficult to attack specific targets such as railway stations by night. The Battle of Britain had thus forced the Germans to adopt night bombing - a method of attack in which they did not believe, and for which they had not fully prepared themselves. One further consequence of the day fighting which adversely affected the German night operations was that the enemy's losses in long-range bombers were so great that he was unable to mount mass night attacks on a decisive scale. The night operations of the Luftwaffe over London in September and October afforded adequate proof that decisive vertical assault depends on the ability to continue to drop great tonnages in concentrated areas without prohibitive loss. It was primarily because the Germans never succeeded in doing this that their night attacks on the capital failed.

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* Convoys relied a great deal at this time upon the protection afforded by flying balloons - as may be seen from an attack which occurred on 11 September. In the evening one of our Channel convoys was moving from the Nore to Portsmouth. The convoy included four trawlers with flying balloons. A first attack was made by three enemy fighters, which concentrated on trying to shoot down the balloons, then flying at about 2,000 feet. Two of the aircraft were driven off by A.A. fire, but the third attacked the balloon on the leading trawler, the Astral, several times. This balloon was later found to be riddled with bullets, but it remained in the air until Portsmouth was reached. During these attacks the enemy had been confused and misled by the rapid alteration in the height of the Astral's balloon. Soon after, a second attack was made by about 20 enemy aircraft, which dive-bombed the convoy. It was noticed that this attack was restricted to the ships forward of the Astral, i.e. the ones unprotected by balloons. A destroyer was hit and a small armed vessel damaged. No dive-bombing was attempted on the Astral, which was still flying a balloon, nor on any of the ships astern of her.
** At the same time every effort was made by Flying Training Command to increase the output of pilots by the methods referred to on page 16.
*** The Polish pilots had a reputation for aggressiveness in air combat during the Battle of Britain, which is also illustrated by an incident which had taken place shortly before. On 5 September a Polish Sergeant Pilot took part in a combat with an enemy bomber formation escorted by fighters in which he destroyed a Me.109 over the Thames Estuary. Later lie was attacked by another Messerschmitt, which he in turn chased in company with two other Hurricanes. The Messerschmitt was forced lower and lower until the Pole was chasing it at `0' feet. At that point, after giving several short bursts, his ammunition ran out. Rather than break off the action the Sergeant charged the Messerschmitt with his Hurricane and flew in so close that the enemy swerved and was caused to crash on the ground.
**** Conflagration is here used in its official sense as a huge spreading area of flames.
***** On 14 September the balloon barrage was increased by a total of 108 winches (= balloons), and by the night of 10th-17th the flying strength had been raised by 44 per cent.
* ***** It was on 19 September that Brigadier Strong, Assistant Chief of the U.S. War Plans Division and head of the American military mission which had been sent to London to observe the results of G.A.F. attacks on this country, arrived back in New York. Brigadier Strong's report that the Luftwaffe had made no serious inroad on the strength of the R.A.F., that the military damage done by air bombardment bad been comparatively small, and that British claims of German aircraft casualties were `on the conservative side', did a great deal to influence American public opinion.
** ***** 607 Squadron also engaged a small raid on Portsmouth at 1800 hours.
*** ***** Long-range bombers took part in the attack on London on 30 September, but (lid not achieve much.
**** ***** The Beaufighters had an adequate performance for night fighting but had not been properly tested out, and difficulties were experienced with their V.H.F. Radio Telephony. By the end of October a few Hurricane squadrons were being used for night work, and these represented a diversion of 8 per cent. of the effective day fighting strength.