The Germans planned an invasion of Britain to destroy her potential for making war. The plan, Operation Sea Lion, called for implementation by the autumn of 1940 and depended on German forces defeating and eliminating the Royal Air Force, clearing the English Channel of British mines, dominating the coastal zone between occupied France and England with heavy artillery, and eliminating the Royal Navy as a threat.
German success relied heavily on its air force, the Luftwaffe, dealing with the R.A.F quickly and efficiently and gaining air superiority over Britain with a series of concentrated bombing attacks throughout the British Isles. Winston Churchill called what followed “the Battle of Britain” – fifteen weeks of aerial combats, much happening directly above the towns and villages of England. The threatened invasion never came. Herman Goring’s vaunted air force failed to achieve the prerequisites for Sea Lion and Adolf Hitler was forced to call it off.
The Luftwaffe bombing raids on Britain continued, however, into mid-May 1941, resulting in an unprecedented fifty-seven night campaign of horror for the British people. The airmen of Goring’s bomber force, sometimes referred to as ‘eagles’, were a unique breed involved in a remarkable experience, a prolonged, dramatic, strategic bombing effort that was met and challenged by a relatively small force of R.A.F fighter pilots determined to do whatever it took to prevent the enemy invading.
The ferocity of fight they put up left the German bomber crews in no doubt about the sort of threat they faced. The Battle of Britain: Luftwaffe Blitz offers a gripping, graphic view of the routine repeated each day and night, from the summer of 1940 through the following spring, by the German bomber crews bringing their deadly cargoes to Britain.
Through mainly German archival photos, it features images of the airmen on their French bases and in the skies over England; the aircraft they flew, fought and sometimes died in; their leaders; their targets and results; the R.A.F pilots and aircraft; and the losses. The images, from the Bundesarchiv and other German and British photographic sources, vividly convey a real sense of events as they played out, as do the compelling memories of many on both sides, participants and eyewitnesses to one of the most brutal sustained bombardments of the Second World War.
By November the bombing campaign had been extended to other British cities and,for the most part, the enemy raiders came and went on their deadly night-bombing assignments with very little response or interference by local or night-fighter defence. The new British Airborne Interception radar system was about to become operational against the night raiders, but had not yet been put to the test and was still essentially experimental.
From the German perspective,the campaign of night-bombing was under way at a lower rate of efficiency than was customary for the Luftwaffe. Its night navigation and bombing accuracy were not up to standard, which was largely due to it having lost so many of its more experienced bomber crews in the run-up to and early part of the Blitz.
The Luftwaffe bomber crews at that point were dependent upon three main blind-bombing and navigation systems.The first was called Knickebein (bent leg) and was utilized in bomber aircraft equipped with a Lorenz blind-approach device. With this system, a pilot flew his bomber along a radio beam to the target. His bomb aimer released the bombload when his aircraft reached a second radio signal that crossed the approach beam. Advantage: the system could be employed by a large number of aircraft. Disadvantage: the system was easily jammed.
The second such system was called X-Gerat (X Equipment) and was made specifically for the Heinkel He III H-4 bombers of Kampfgruppe 100. This system comprised one approach beam that was crossed in the vicinity of the target by three other beams. The pilot received the first such signal some thirty-one miles short of the target, at which point he accurately aligned his aircraft on the approach beam. The second and third traversing beams were reached at twelve miles and three miles from the target respectively. A system computer then used the groundspeed of the aircraft to set an automatic bomb release point when the third beam signal was received. Advantage: highly accurate. Disadvantage: the system could be easily jammed.
The third such system used by the German bomber crews early in the Blitz was Y-Gerat (Y equipment), a bombing aid used only in the He IIIs of III/KG 26. In this system, bomb release occurred at an accurately-measured point along an approach beam.The range computation was made by a ground radar station which sent a pulse signal to the bomber. After an established interval the bomber returned a pulse to the ground station and the range to the bombing point was then computer-calculated in milli-seconds. The ground station then relayed the bomb-release signal. Advantage: very accurate. Disadvantage: readily jammed.
Night navigation and bombing aid accuracy were not the only problems that the Luftflotten 2, 3 and 5 had to cope with in their Blitz attacks on London and the other major cities of Britain. ln theory, the Luftwaffe had upwards of 1,3OO bombers available for use in the attacks, but in practice only about 700 were actually serviceable and employed in the raids.
In the month that followed the huge daylight raid of 7 September on the London docks, an average of between sixty and 260 bombers were utilized each night.The Knickebein blind-bombing and navigation system was the primary system in use during October, and was effectively jammed by RAF Signals personnel, reducing the navigation and bombing capability of the Germans to reliance on moonlight.
From 9 October, the German bomber fleets were ordered to raise the bomb tonnage they were delivering, in an increased effort to panic the British civilian population and force a capitulation. But,just as they had failed in securing air supremacy over England in the Battle of Britain,they failed too in this effort.
That failure led to an expansion by Goering ofthe present bombing campaign to one in which a lengthy attrition of British war-related industry was the goal. It was then that the X-Gerat navigation and bombing system entered service with the bombers of KGr I00. It was utilized in conjunction with the dropping of incendiary bombs for target-marking purposes in aid of the main bomber force to follow in to the target area.
In an early example of the X-Gerat system deployment, KGr I00 attacked the city of Coventry on the night of 14/15 November In the attack, a dozen Heinkel He IIIs dropped more than 1,000 incendiaries on the city at 8:15 p.m.to mark it for the three separate main bomber streams then approaching from the directions of the Wash, Portland, and Dungeness. The terrifying raid lasted through the night, with wave after wave of bombers — 469 sorties in all – blasting Coventry with nearly 400 tons of high explosives, as well as fifty-six tons of incendiaries and 127 parachute sea-mines. Once again,there was little in the way of air defences; an easy night for the raiders.
Not so easy, however, on the night of 19 November, when the German bomber force attacked Birmingham in a heavy raid that cost the attackers five of their aircraft. Keeping up the large-scale attacks through the rest of November and December, the Luftwaffe struck heavily at Southampton, Sheffield, Liverpool, Bristol, Plymouth, and London.
Only the relatively sudden appearance of rapidly deteriorating weather put a stop to a massive raid on London in the night of 29 December 1940 after two hours of attacking.The 130 sorties flown that evening were all incendiary deliveries and, despite the early curtailment of the raid, by 10 p.m. the number and scale of the raging fires in the City area of London exceeded the scale of the Great Fire of 1666.The bulk of the incendiaries fell just to the north- west of St Paul’s Cathedral and the fires they started served to guide the delivery of the high explosives of the main bomber force that followed.
By January 1941 ,the Luftwaffe had developed a distinct lack of confidence in the X-Gerat system of blind-bombing aid, and that, in combination with the RAF’s ability to jam the system, together with its growing use of decoy fires, helped to force the Germans to navigate and bomb mainly by moonlight and to again redirect their targetting now to the British seaports of Swansea, Cardiff, Bristol, Hull and Plymouth.