The Germans had all the air superiority they needed to invade, but the German High Command still wanted more. The Luftwaffe had been set the task of destroying Fighter Command. It had failed to achieve this, and it seemed unlikely that the Air Force would succeed in this aim before the weather broke and invasion became impossible. It was not obvious that the German fighter force could maintain the offensive much longer. Operating over enemy territory in a fighter with a very limited endurance imposed an enormous strain on the pilot. A close eye had to be kept on the petrol gauge and there was always the possibility of having to fly back over the Channel in a damaged machine. The defending fighters had all the advantages Dowding had always insisted he needed. Every time a German fighter was shot down over Britain, the pilot was lost as well, whereas a British pilot was often back with his squadron the same day. RAF fighters that crash-landed could be repaired, but Messerschmitts that were forced down were lost. Production of the Bf 109 was actually running at a lower level than Spitfire/Hurricane production. Ironically, while Dowding was considering the possibility of using the French Curtiss Hawks to reequip squadrons in the rear, the Germans were seriously considering reequipping some of their squadrons in the rear with captured French Bloch 152 fighters.
The battle in the skies was becoming a stalemate. The German Air Force was no nearer to its goal of eliminating Fighter Command, but RAF fighters were not making any substantial inroads into the German bomber force either. On 3 September, with air supremacy still not established, Hitler put the invasion date back a week to 21 September. The British were unaware of this postponement; they were only aware an invasion was imminent. Reconnaissance planes were picking up the movement of invasion barges making their way to the Channel ports.
While the air forces battled it out, the respective armies prepared as best they could. From nothing, the German Navy conjured up an invasion fleet with all manner of improvised landing craft. There were even submersible tanks and a primitive artificial harbour. The British Army was still in a desperate state, but the American government had responded magnificently; the US Army pulled hundreds of thousands of obsolete rifles, tens of thousands of machine guns, and hundreds of artillery pieces and mortars out of stores and shipped them across the Atlantic. Even so, only four of the twenty-seven divisions were considered to be fully equipped. There were just two armoured divisions and six independent tank brigades, with no more than 600 tanks in the entire country. Churchill remained bullishly optimistic any invasion would be defeated, but Brooke was not so confident; he did not think his forces were sufficiently trained, powerful, or mobile to defeat the mighty Wehrmacht. He desperately hoped his forces would at least get a winter of training before being put to the test.
With air reconnaissance picking up barges heading for the Channel ports, it seemed Brooke was not going to get his wish. It was only now that the British Chiefs of Staff realised the invasion was likely to come along the south coast rather than the east. From the night of 6–7 September, the Battles and Blenheims of Nos 1 and 2 Groups, supported by Fleet Air Arm and Coastal Command squadrons, began bombing the ports where the barges were congregating. The following night, twenty-six Hampdens joined them, but the threat of imminent invasion was not allowed to disrupt the heavies’ offensive against German industry. On 8 September, Invasion Alert No. 1 was released, but it was another week before Nos 3, 4, and 5 Groups switched all their efforts to the Channel ports.
When cloud cover allowed, Blenheims attacked by day, but coastal targets are always relatively easy to find by night, and the growing mass of invasion barges made for an attractive target. In ten days, around 1,000 sorties were flown against the ports. Up to 21 September, air and sea attack resulted in about 10 per cent of the invasion fleet being destroyed or damaged. The number that survived was another reminder of how surprisingly little damage bombing can inflict even on such an apparently vulnerable target. The bombers had made a useful contribution, but ample craft remained to set course for Britain.
There was never any doubt that the Navy would have risked all to sink the invasion fleet in transit and bombard any forces that landed. The time it took for Bomber Command to switch its main effort from German industry to invasion ports did not suggest the Air Force response would be so spontaneous. In the three months since the defeat of France, virtually no progress had been made in preparing the RAF to support the Army any more effectively than it had in May and June. If anything, the Air Force was less prepared. Tactical air support was going backwards.
There was no equivalent to the tactical BAFF that had existed in France. The Air Ministry had refused to create an Army Cooperation Command. The Combined Operations Room existed to pass on requests for fighter and bomber support, but Fighter and Bomber Command had not made any serious preparations to prepare their squadrons to respond. Early in September Fighter Command was reminded of its bomber escort and fleet defence responsibilities; at the very bottom of the list of priorities came protecting the troops from the Stukas. It rather underlined how short of fighters the RAF was. To have any chance, the RAF needed to mobilise every available fighter pilot and fighter in the country, regardless of their country of origin.
On 14 September, with the invasion expected any day, the Air Ministry was reminded that Fighter Command cannon-armed fighters must be held back for ground-attack duties; unfortunately, Fighter Command no longer had any. No. 19 Squadron had the cannon removed from their Spitfires because they jammed so often, and nothing came of the plan to arm Blenheims with them. Plans to equip more Hurricane Is with cannon had been postponed until the Hurricane II became available, and the four-cannon Whirlwind was still struggling with its unreliable Peregrine engines. Fighter Command did not have an anti-tank capability.
Slessor’s Plans department did not see this as an Air Force problem—it was the Army and ‘its Lysanders’ that must first deal with tanks once they got ashore. Unfortunately, these were not armed with cannon either. The army-cooperation squadrons were still administratively part of Fighter Command, so it was Dowding’s responsibility. When Deputy Chief of the Air Staff AM Shoto Douglas quizzed Dowding, he claimed to be completely unaware and very ‘perturbed’ that this instruction had not been carried out. He might argue that nobody in Fighter Command had the time to worry about army-cooperation squadrons or any cannon ground-attack capability. It would be difficult to dispute that, but it was also a rather obvious example of why the ‘Army Cooperation Command’ the War office wanted was so necessary.
Bomber Command had grown in strength during the summer. No. 2 Group had thirteen squadrons, with over 200 Blenheims immediately available. The four Polish Battle squadrons being formed brought the number available to No. 1 Group to eight, but no effort had been made to improve their ground-attack capabilities by adding armour or increasing their ground-strafing capability. The Battles had still not been equipped with self-sealing tanks. Instead of getting Bostons or Marylands, the first two squadrons (Nos 103 and 150) had begun converting to the Wellington.
The fate of the American combat planes was bordering on a scandal. American aircraft companies were modifying the ex-French aircraft to British standards and rushing them across the Atlantic as fast as they could, along with any artillery, machine guns, and rifles the American Army could spare. Obsolete artillery was gratefully received and distributed amongst the divisions. Equally obsolete rifles were handed out to the 500,000-strong Home Guard. Brand new, modern American combat planes, however, were left unused. Around 300 had arrived by the end of August, of which only half had been assembled. Bomb racks for Tiger Moth trainers and constant-speed propellers for Spitfires had been conjured up and fitted in weeks, but not a single American bomber or fighter reached a front-line squadron.
What the Prime Minister would have made of it can only be imagined. Churchill had told Sinclair how ‘shocked’ he was to see so many communication aircraft on a visit to Hendon. He felt these and their pilots could form ‘two good fighter or bomber squadrons of the reserve category’, which could be used in an emergency. Churchill might have been even more shocked if he had known about all the unused American combat planes and the unemployed Polish and Czech pilots who might have flown them.
The resources existed for a useful tactical air force, but too many within the Air Force did not believe it was their duty to provide it. In September 1940, the RAF had no specialist close-support capability and no high-speed tactical-reconnaissance planes. Bomber Command was focusing on Germany, and Fighter Command was totally consumed by its battle for survival. Winning this battle was becoming the only opportunity for the RAF to make a significant contribution to stopping an invasion. It need not have been so; Fighter Command’s furious defence of British skies should have been just the first RAF obstacle the Germans had to overcome. Instead, it was the RAF’s last stand. For the Luftwaffe, invasion would have meant a welcome return to its more familiar Army-support role. For the RAF, it was a transition the force was incapable of making. The air battle Fighter Command was engaged in was even more crucial than it need have been. The RAF might be able to prevent an invasion, but it could do very little to help defeat one. For the RAF, there was no Plan B.
That air battle was now reaching its climax. At the beginning of September, after a month of intense fighting, both sides were looking for new solutions to break the deadlock. To win the battle, the Luftwaffe needed to shoot down more RAF fighters. To achieve a decisive victory, Fighter Command needed to shoot down more bombers. Avoiding defeat, however, might be enough—provided the German High Command did not change its mind about requiring air supremacy. In this respect, the battle was still on a knife-edge. Britain needed Germany to stick to its plans.
Luftwaffe commanders were divided about how close to defeat Fighter Command was. Figures of British fighter strength produced by German intelligence fluctuated between 100 and 350. Field Marshal Sperrle, the commander of Luftflotte 3, believed Fighter Command still had 1,000 planes. Field Marshal Kesselring, at Luftflotte 2, insisted Dowding’s force was almost finished and one final push would see total victory achieved—it just required the last remnants of Fighter Command to be induced into the air. Circumstances conspired to give Kesselring the decisive battle he wanted. On the night of 25–26 August, German aircraft dropped some bombs on central London by mistake. Whitleys retaliated with an attack on Berlin. Neither of these raids caused much damage, but Hitler’s pride was hurt. He wanted retaliation, and this gave Kesselring his opportunity. Surely the British could be relied on to throw in every last reserve in defence of their capital—the destruction of Fighter Command would still be the objective, but London would be the battleground.
The attack was launched on 7 September. The sudden change in focus took Fighter Command controllers by surprise. Squadrons had to be hurriedly switched from blocking the path to their airfields to the bombers heading for the London Docks. Once again, the escort bore the brunt of the Fighter Command assault. Fourteen Bf 109s and seven Bf 110s were lost, but only eight of the attacking 348 bombers. With Fighter Command losing thirty-seven Hurricanes and Spitfires destroyed or seriously damaged, it was another tactical victory for the Luftwaffe.
The bombing was concentrated and heavy. In ninety minutes, 300 tons fell on the East End. Warehouses, gasworks, and oil depots from Tower Bridge to Thames Haven were left blazing, and although the targets were legitimate, there was heavy loss of life. For London, it was just the beginning—the blazing fires clearly marked the way for the night bombers that would follow—but London’s suffering was Fighter Command’s salvation. The immense pressure of operating from airfields that were constantly under attack was lifted. Fighter Command stations had the respite they desperately needed. It was one of the great ironies of the war; the Command had been set up to defend London, but in the end, it was London that saved Fighter Command.
Too many advantages now lay with the RAF fighters. The Bf 109 would be operating at the very limit of its range; it was now a very long return flight. Park had more time to pair up his squadrons and get them into position at adequate patrolling altitudes. London was also reasonably close to where both No. 12 and No. 10 Groups converged with No. 11 Group, which would now allow Dowding’s fighters to be concentrated in a way that had not previously been possible.
The next day, there was a noticeable relaxation in Luftwaffe pressure. For the first time in many days, not all squadrons were placed on readiness. In the operations that were flown, there was a growing wariness amongst the German fighter pilots as they sought to counter the high-flying British fighters by flying well above the bombers they were supposed to be escorting. It was a defensive move by the fighters that left the bombers more exposed.
On the 9th, the German escorts again absorbed a lot of the Fighter Command effort. Fighter Command pilots attempted to counter the freer, high-flying German fighter formations by flying higher themselves. Altitude was everything; controllers were adding a few thousand feet to be on the safe side, and squadron commanders would invariably add a few thousand more. Bomber formations at medium altitude were getting through unhindered. Dowding ordered his sector controllers to stick to the altitudes radar was indicating. Eighteen escorts were lost, but the defending fighters probably only shot down five enemy bombers. Another twenty-three Hurricanes and Spitfires were lost.
Poor weather on the 10th prevented much activity and provided yet more time for Fighter Command to catch its collective breath. On the 11th, the premature departure of the escorting Bf 109s of LG 2 and JG 51 through lack of fuel emphasised how stretched the German fighter force now was. Hurricanes and Spitfires took advantage, shooting down seven bombers and damaging ten. Two days of relatively light activity kept German losses to a minimum but also provided yet more time for Fighter Command to prepare for the climax of the battle.
The more relaxed atmosphere at sector stations was in stark contrast to the growing tensions between Park and Leigh-Mallory. Bader had led his Duxford Wing into action for the first time in the 7 September raid on London, with No. 19 Squadron (Spitfires) covering the Hurricanes of Nos 242 and 310 Squadrons. By the time they reached their patrol altitude, the German bombers were starting to head for home, and Bader’s fighters only engaged the rear-guard escorts. On the 9th, his wing was called on again; this time, they claimed an astonishing nineteen Do 17 bombers. This seems to have been a gross exaggeration; German records do not actually record any Dorniers lost that day. More successes were claimed on the 11th, with elements from four squadrons forming a three-squadron-strong wing. Bader still felt there were insufficient fighters to take advantage of the disorder the initial attack had caused, and that more than one squadron was needed to keep off the German escort. Five squadrons was a more satisfactory number, with two Spitfire squadrons to take on the escort and three Hurricane squadrons to deal with the bombers.
Park did not take kindly to Leigh-Mallory’s claim that his tactics were better than those that No. 11 Group was using. He blamed the late arrival of Leigh-Mallory’s fighters on the need for these cumbersome wings to form up and made it clear he would prefer one squadron patrolling his airfield in fifteen minutes rather than several arriving too late. If wings had to be used, they should form up over the airfields he had asked them to defend. It was a tetchy response, demonstrating the strain Park was under. He correctly felt that winning the battle was his and No. 11 Group’s responsibility. Perhaps understandably, he saw any unsolicited help or advice that he should be fighting the battle any differently as a suggestion that his Group was not coping and evidence of personal weakness.
In practice, there was not a great deal separating the fighter formations the two Groups were using. Park seems to have been won over by his commanders’ insistence that squadrons should go into action in pairs. By 11 September, Park was instructing his controllers to use pairs whenever possible. Ideally, Park wanted a pair of Hurricane squadrons to be covered by a pair of Spitfire squadrons operating 5,000–8,000 feet higher. This was not as closely coordinated as Bader’s idea of two Spitfire squadrons 3,000–4,000 feet above a wing of three Hurricane squadrons, but the principle was the same.
Bader did not agree that using larger formations wasted valuable time, partly because he saw no advantage in the tight, rigid formations that were still common in Fighter Command. Any ‘forming up’ could be done on the way to the designated patrol zone. If his wings arrived too late, it was only because they had not been scrambled in time. With radar providing plenty of early warning, there was nothing to stop Bader getting the extra time he wanted.
Dowding saw no reason to intervene in the dispute, but giving his Group commanders free rein looked like tacit support for Leigh-Mallory, which must have offended his protégé, Park. To his critics in the Air Ministry, it looked like a lack of leadership. In the Park/Leigh-Mallory dispute, the ministry tended to side with the latter; there was growing frustration at the cantankerous commander-in-chief’s failure to make better use of No. 12 Group. It was all rather unsavoury, but for the RAF it all worked out well for the decisive assault on 15 September.
On this day, the Luftwaffe launched two raids on London. Both were relatively small compared to previous raids, but both also had massive escorts. The German crews set off, encouraged by claims that Fighter Command was down to just a handful of fighters. The first raid consisted of fifty bombers and 150 escorts. Park’s squadrons engaged as soon as the formation crossed the coast, harassing the bombers all the way to London. Up to this point, the escorts had done a reasonably good job, but over the capital, four more Hurricane squadrons and Bader’s wing of two Spitfire squadrons and three Hurricane squadrons hit the German formation simultaneously. The remaining escort was swamped and the closely packed bomber formations scattered. The crews dropped their bombs haphazardly and headed for home as best they could.
In the afternoon, a second wave of bombers had no better luck. One hundred and fourteen bombers with around 500 fighter escorts crossed the Kent coast and headed for London. On the approach, German escorts again successfully fended off the efforts of No. 11 Group but they burned precious fuel in the process. Over London, six squadrons from No. 11 Group, two sent over from No. 10 Group, and the five squadrons of No. 12 Group’s Duxford Wing broke through the now scattered German escort. Once again, the bombers hurriedly dumped their loads on the suburbs before being chased back to France. Demoralised bomber crews described how formations of eighty enemy fighters had met them over the capital. The Luftwaffe lost sixty-four planes; these losses were serious, but the psychological blow of meeting such formidable formations of fighters was even greater. It was now clear to Luftwaffe aircrew and their commanders that Fighter Command was still a very effective force. On 17 September, the invasion was postponed indefinitely.
As RAF reconnaissance followed the transfer of the invasion barges from the exposed Channel ports to safer inland waterways, the Army and country breathed a collective sigh of relief. Brooke had no illusions—it was no more than a postponement. With the return of favourable weather the following spring, the invasion threat would be renewed. Britain had won a valuable six-month breathing space, but that was all. Nevertheless, Brooke would now get the winter he needed to train his army.
Britain had been fortunate. The German Navy had never required air superiority over central London—for an invasion to be successful, the Luftwaffe merely had to control the skies over the Channel and the German bridgeheads. Arguably, the Luftwaffe had long since achieved this objective. Fighter Command would never have been able to achieve the degree of concentration over a beachhead as had been possible over London, and German fighters would not have been operating in such difficult circumstances.
For the Luftwaffe, it was another failure. The German fighter force was good enough to establish a degree of air superiority, but eliminating Fighter Command had proven impossible. Fighter Command ended the summer of 1940 tired and battered, but it had more pilots and planes than at the beginning of the battle. The Luftwaffe had not even come close to destroying it. For the second time in a matter of months, the Luftwaffe had been set the task of achieving results on its own; just as had happened over Dunkirk, it failed. Fighter Command had done well in a battle where it only had to focus on the enemy air force. How well it would have done dealing with an enemy invasion will never be known.
With hindsight, the retreat of the invasion fleet signalled the end of the immediate danger, but this was not how it was seen at the time. The withdrawal of the invasion barges was a relief, but invasion was only one of the threats facing Britain, and for many it was not the most feared; the bomber still remained.
Dowding was in no doubt that the danger had not passed. The air offensive against Britain had not been halted. It was merely evolving. There had always been reasonable confidence that a daylight offensive could be dealt with, but it had always been assumed that once defeated by day, the enemy would merely turn to bombing by night. This would not be some futile act of despair by a defeated and bewildered enemy, but rather a natural progression to an offensive that posed even greater danger. Douglas had no doubt that bombing alone could bring Germany victory. At a dinner party, he was appalled by the naivety expressed by a prominent politician who claimed the bomber was overrated as a weapon of terror and could never bring any country to its knees. Douglas put the counterargument to him so strongly he found himself reported to Churchill for defeatism.
For Dowding, Douglas, and many in the Air Ministry, the battles of July, August, and early September were just the prelude to the main event. The long-awaited assault on British cites was finally underway. The civilian population would now become the principal target. This was the air war the Air Staff had always predicted, the battle they and the politicians had always most feared. It was far more dangerous than mere invasion and the German Panzer blitzkrieg; indeed, the air element of the German blitzkrieg was so prominent in the public mind that the new strategy was seen as merely an extension of the old, a purer form of the strategy with the irrelevant Panzer element removed. The transition was so smooth that the British public and press kept the same name—the German bomber offensive was referred to as the ‘blitzkrieg’, soon abbreviated to ‘the Blitz’.
As far as the Air Staff were concerned, the real war was just beginning.