Black Thursday

On Thursday 15 August 1940 the Luftwaffe made its greatest effort of the entire Battle of Britain. For the first and last time all three air fleets deployed against Britain attacked simultaneously: from northern France and Belgium, from Normandy and Brittany, and from Norway and Denmark. From the south coast to Northumberland the Germans flew some 1,800 sorties that day, more than 500 of them by bombers. They bombed airfields, radar stations and aircraft factories, and towards evening bombs fell for the first time on the outskirts of London. The price was very high. The Luftwaffe lost about 75 aircraft, more than twice as many as the RAF, and the raid from Norway, which was supposed to surprise a north of England that was allegedly unprepared, ended in disaster. In the literature the day is known as the Luftwaffe’s “Black Thursday”; the British called it “The Greatest Day”. The next day, 16 August, the Germans attacked again, and their problems, from the short range of their fighters to their helplessness in the face of British radar, showed themselves even more clearly.

After Eagle Day

Under Hitler’s Directive No. 17 of 1 August, the Luftwaffe was to defeat the British air force as quickly as possible to make a landing on the British Isles possible. The great offensive against airfields and radar stations began on 13 August, on Eagle Day, but the first days did not bring what Hermann Göring had expected. The attacks were poorly co-ordinated, some raids were recalled, and bombs often fell on airfields that did not belong to Fighter Command. On 14 August, in bad weather, the Germans flew less. The forecast for 15 August predicted cloud, so Göring summoned the commanders of his air fleets and air corps that day to a conference at his residence, Carinhall, near Berlin.

In the morning, however, the sky over the Channel cleared. According to accounts cited by historians of the battle, the decision to carry out the previously prepared plan for a great strike was taken, in the absence of his superiors, by the chief of staff of II Fliegerkorps, Oberst Paul Deichmann. The plan assumed that attacks from the south would draw the British fighters over Kent and Hampshire, while General Hans-Jürgen Stumpff’s Luftflotte 5 struck from Norway and Denmark at the airfields of north-east England. German air intelligence assumed that Dowding had stripped the north of fighters to defend the south.

The first blows in the south

Before noon some forty Junkers Ju 87 dive-bombers, escorted by Messerschmitt Bf 109 fighters, attacked the forward airfields at Hawkinge and Lympne on the Kent coast. Lympne was badly damaged and put out of action for several days. At the same time bombs cut the power supply to several radar stations on the Kent coast, which stopped working for a while. Hurricanes and Spitfires shot down several Stukas, but the main battle of the day was to be fought far to the north.

The defeat of Luftflotte 5

At around midday British radar stations in Scotland and Northumberland detected a large formation of aircraft approaching over the North Sea. It consisted of 63–65 Heinkel He 111 bombers of KG 26, which had taken off from Stavanger in Norway, escorted by a few dozen (21 to 34, according to different studies) twin-engined Messerschmitt Bf 110 heavy fighters of ZG 76. The single-seat Bf 109s could not have flown more than 600 kilometres over the sea and back, so they took no part in the raid at all. The Bf 110 crews left their rear gunners behind and fitted extra fuel tanks under the fuselage simply to reach England and return. A planned feint, a flight by seaplanes towards the Firth of Forth, failed to draw off the defences, because a navigational error took the main formation too close to the diversionary route and the radars tracked both groups at once.

The British had time to prepare. No. 13 Group, responsible for the north of England and Scotland, scrambled its squadrons. The first Spitfires, of No. 72 Squadron, caught the Germans over the sea near the Farne Islands; then, over the coast between the Tyne and the Tees, Hurricanes of Nos. 605, 607 and 79 Squadrons and Spitfires of No. 41 Squadron struck. British pilots who had expected perhaps a dozen or so aircraft were astonished to see more than eighty. The Bf 110s, heavy and unwieldy, were unable to protect the bombers and themselves became easy targets. The escort commander, Hauptmann Werner Restemeyer, was killed. The formation broke up. Many Heinkels jettisoned their bombs into the sea or on random spots along the coast, including houses in Sunderland, and turned back.

Somewhat further south, over Yorkshire, about fifty Junkers Ju 88 bombers of KG 30 attacked, having flown from Denmark without fighter escort. They were intercepted by squadrons of Air Vice-Marshal Trafford Leigh-Mallory’s No. 12 Group, but some of the bombers got through to the RAF airfield at Driffield. It was a Bomber Command station, not a fighter base. Bombs hit the hangars, destroyed or damaged a dozen or so aircraft on the ground, mainly Armstrong Whitworth Whitley bombers, and killed or wounded more than twenty people.

The outcome of the northern raid was catastrophic for the Germans. According to the figures cited in most studies, Luftflotte 5 lost about twenty aircraft – most often given as 16 bombers and 7 fighters – or roughly one in six of the aircraft that had taken off. British losses were limited to a few damaged fighters and wounded pilots. The assumption that the north had been left undefended proved false. Dowding had not moved all his forces south, because his system allowed him to defend the whole country while also giving a rest to exhausted squadrons from the south, which he sent north. Luftflotte 5 never again attempted a daylight raid on England, and its bomber units were later moved to France and Belgium.

Afternoon and evening in the south

In the south the fighting went on until evening. After 2 p.m. Dornier Do 17 bombers of KG 3, with a strong fighter escort, attacked Kent. Some of them bombed the Short Brothers works at Rochester on the Medway, where the new four-engined Short Stirling bombers were being built. Several finished aircraft and the assembly sheds were destroyed, delaying production of the bomber by many months. Other formations struck the airfield at Eastchurch. A dozen or so fighter-bomber Bf 110s and Bf 109s of Hauptmann Walter Rubensdörffer’s trials unit, Erprobungsgruppe 210, raced in at low level over Suffolk and bombed the airfield at Martlesham Heath, which was unusable for two days.

At about 5 p.m. Field Marshal Hugo Sperrle’s Luftflotte 3 sent some two hundred aircraft over Hampshire and Dorset. Ju 88 bombers attacked the sector airfield at Middle Wallop and the Fleet Air Arm airfield at Worthy Down, but did little damage. A dozen or more squadrons of Nos. 10 and 11 Groups fought heavy battles over the coast, in which the Germans lost more than twenty aircraft, many of them Bf 110s, and the RAF a dozen or so fighters.

In the evening, shortly before seven, Erprobungsgruppe 210 set out on its second attack of the day. Its target was the sector airfield at Kenley, but the pilots mistook their target and bombed the airfield at Croydon, a few kilometres away, formerly London’s main airport. Bombs fell on the hangars, the terminal building and the factories adjoining the airfield. Six members of the airfield staff and 62 civilians, mostly workers in armaments factories, were killed, and nearly 200 were wounded. It was the first serious raid on the Greater London area, even though Hitler had at that time forbidden the bombing of the capital. Over the target Erprobungsgruppe 210 was intercepted by Hurricanes of Nos. 32 and 111 Squadrons. The group lost seven aircraft, and Rubensdörffer was among the dead.

The tally and the reckoning of losses

According to post-war tallies based on the records of both sides, the Luftwaffe lost about 75 aircraft on 15 August. More than a hundred aircrew were killed or captured. Fighter Command lost more than 30 fighters in combat, and a dozen or so airmen were killed. The difference was thus large, but not as enormous as both sides claimed. The Air Ministry in London announced 182 German aircraft shot down, and the press and radio described the day as a great victory. German pilots also claimed far more kills than were real, and the German high command went on believing that the RAF was rapidly losing strength.

Göring drew his own conclusions at the Carinhall conference. According to the surviving record, he said it was doubtful whether there was any point in continuing to attack the radar stations, since not one of those attacked so far had been put out of action for long. The Germans thus abandoned systematic attacks on the radars – the foundation of the British defence – just as they were beginning to take effect. Göring also decided that no more than one officer should fly in any one crew, because the Luftwaffe was losing too many experienced commanders.

Beaverbrook’s factories

Some chronologies note under 15 August that British fighter production was beginning to accelerate. In reality it had been accelerating for three months. When Winston Churchill became Prime Minister on 10 May, he separated aircraft production from the Air Ministry and entrusted it to a new minister, the press baron Lord Beaverbrook. Beaverbrook, a man of enormous energy and no respect for procedure, made the factories concentrate on a few types of aircraft, above all the Hurricane and Spitfire fighters; he took raw materials and machine tools from other departments, took over from the air force the storage units and repair depots in which hundreds of undelivered aircraft stood, and organised the repair of damaged machines on a large scale.

The effects were immediately visible. In the first four months of 1940 British factories delivered 638 fighters, and in the next four, from May to August, 1,875. Nearly 500 fighters were produced in July and about 470 in each of August and September – roughly twice as many as the Germans were building Messerschmitt Bf 109s. On top of this came hundreds of machines repaired in the workshops of the civilian repair organisation, which returned to the squadrons after a few days or weeks. Historians debate how far this was Beaverbrook’s personal achievement and how far the fruit of decisions taken before the war, when new factories were built and increased production was planned. Hugh Dowding himself, however, later wrote that Beaverbrook had given him the aircraft without which he could not have withstood the battle of attrition. By mid-August Fighter Command had more fighters than at the beginning of July, despite its losses. What it lacked was rather experienced pilots.

16 August

The next day the Germans again flew some 1,700 sorties. Before noon bombers attacked the airfield at West Malling in Kent, which was afterwards out of action for several days, as well as targets in the Thames Estuary. At about 1 p.m. a formation of some 150 aircraft from Cherbourg came in over Sussex and Hampshire. Several dozen Ju 87s of StG 2 fell on the sector airfield at Tangmere near Chichester. They destroyed hangars, workshops, the officers’ mess and a dozen or so aircraft on the ground, and a dozen or so people were killed. In the fighting over the airfield a pilot of No. 601 Squadron, the American Billy Fiske, a two-time Olympic bobsleigh champion, was wounded. He brought his burning Hurricane back to Tangmere but died the next day; he was the first United States citizen to be killed in this war as an RAF pilot. Other formations again attacked the radar station at Ventnor on the Isle of Wight, already put out of action on 12 August, and the Fleet Air Arm airfields at Gosport and Lee-on-Solent. In the afternoon two Ju 88s dropped bombs on the training airfield at Brize Norton, where according to British figures they destroyed 46 aircraft in the hangars, mostly trainers.

That day over Southampton, Flight Lieutenant James Nicolson of No. 249 Squadron, who had taken off from Boscombe Down, was attacked by Messerschmitts. Cannon shells wounded him and set his fuel tank alight. As he was preparing to bail out of his blazing cockpit, he saw a German aircraft in front of him. He got back into his seat, attacked it and kept firing until the German began to go down. Only then did he jump, badly burned. As he came down by parachute he was fired on by volunteers of the local defence force (Home Guard), who took him for a German. Nicolson survived, and in November 1940 he was awarded the Victoria Cross, the only one given to a Fighter Command pilot during the war. He was killed in May 1945 over the Bay of Bengal.

On 16 August the Luftwaffe lost about 45 aircraft, the RAF more than 20 fighters, some of them on the ground.

Short range and radar

The Germans were hampered by the short range of their aircraft and by British radar. Both days showed this very clearly. The Bf 109, the only German fighter equal to the Spitfire and the Hurricane, had fuel for the Channel crossing and for a quarter of an hour, at most twenty-odd minutes, of combat over Kent and Sussex. Over London it could fight for a few minutes at most, and raids on central and northern England had to do without its protection altogether. The twin-engined Bf 110, which Göring regarded as a long-range escort fighter, itself needed protection in combat with single-engined fighters. On 15 August the Luftwaffe lost about 30 of them, the most in a single day of the whole battle. The Ju 87 dive-bombers, so dangerous over Poland and France, suffered enormous losses over England whenever they lacked a strong escort.

On the other side stood the Dowding system. The Chain Home radar stations detected German formations while they were still assembling over France, Belgium or the North Sea, and the group and sector operations rooms directed the fighters to where they were needed. That is why, on 15 August, squadrons that according to German intelligence should not have been there were waiting for the Germans over the Tyne. The Germans did not understand how the system worked. The radar towers, narrow steel lattices, were hard to hit, and damaged stations were quickly repaired or replaced by mobile ones. The attacks on airfields often struck bases that did not belong to Fighter Command, such as Driffield, Brize Norton or the naval air stations, and German intelligence overestimated the damage and the RAF’s losses.

Place in the war

15 August was the day of the Luftwaffe’s greatest effort in the Battle of Britain and one of its costliest days. The defeat over northern England showed that the RAF could not be taken by surprise and that without fighter escort bombers stood no chance by day. The following weeks, however, were to be the hardest for the British. On 18 August there was another great battle over the airfields at Kenley and Biggin Hill, and after the Carinhall conference Göring ordered his fighters to escort the bombers more closely and withdrew the Ju 87 from the main battle. From 24 August to 6 September attacks on the sector airfields of Air Vice-Marshal Keith Park’s No. 11 Group wore down Fighter Command, which was losing pilots faster than the schools could train them. Only when the Luftwaffe turned against London on 7 September did the airfields get a respite. Beaverbrook’s production and the defence system that had inflicted such heavy losses on the Luftwaffe on 15 and 16 August enabled the RAF to survive this period. After the defeat of 15 September Hitler postponed the invasion of Britain, and in the autumn he in effect abandoned it.