The Bombing War: Europe 1939–1945

by Richard Overy

  The damage sustained by the German aircraft industry was difficult for the Allies to gauge, not least because air intelligence estimates of German production by this stage of the war greatly understated the reality. The MEW estimates of German fighter production for the first half of 1944 was 655 a month, whereas the reality was 1,581 and rising steadily.268 The aero-engine industry, more difficult to disperse and more vulnerable, was not attacked, a failure that Göring later pointed out to his post-war interrogators.269 The attacks accelerated the further dispersal of the industry and prompted a programme for underground construction in which aircraft had a priority, a planned 48 million square metres of floorspace out of a provisional total of 93 million.270 Output nevertheless continued to increase rapidly despite the bombing, which has encouraged the view that Operation Argument effectively failed. The figures show, however, that the Allied attacks, which continued intermittently thereafter, did reduce planned fighter output substantially below expectations. Between January and June 1944, 9,255 German single-engine fighters were produced instead of the planned 12,667, a shortfall of 27 per cent. The heaviest loss was experienced in February 1944 with a shortfall of 38.5 per cent of planned output.271 Not all of this loss was due to bombing, since many other factors affected industrial performance by 1944, but the impact in February almost certainly was. The problem for Allied calculations was the failure to apprehend the rapid conversion in Germany to fighter priority and the successful rationalization and reorganization of aircraft production.

  Spaatz also planned to attack oil facilities, particularly those producing aviation fuel, which were more vulnerable than aircraft assembly halls because of the large capital plant involved and the difficulty of dispersing or concealing them. Intelligence on German oil supplies was the reverse of aircraft production, consistently overestimating German synthetic production and imports. Reluctance to renew an oil offensive after the RAF failures of 1940 and 1941 was based partly on the belief that Germany had large concealed stocks available. By spring 1944, however, Allied intelligence indicated a growing oil vulnerability in Germany. Spaatz set up a planning committee in February 1944 composed of members of the Enemy Objectives Unit to report on other target systems that would accelerate German Air Force decline, and the committee report, presented to him on 5 March, highlighted oil as the principal factor, followed by rubber and bomber production. The economists calculated that enough damage could be done to current oil production to force the German armed forces to consume remaining stocks and that this was the quickest way to undermine fighting power.272 Spaatz willingly accepted the argument and used the new oil plan to make his case, unsuccessfully, against the diversion of his resources to the tactical ‘Transportation Plan’. The aim to destroy or immobilize 27 key oil targets was presented to Portal and Eisenhower as a surer way to undermine German military mobility at the front line, but the estimate that it might take three months to do so made oil plants, in Portal’s view, a long-term objective. Instead, the ‘Transportation Plan’ won the day.

  In the end Spaatz succeeded in undertaking attacks on German oil targets by sleight of hand. In April 1944 the Fifteenth Air Force began a number of raids against the Romanian oil-producing city of Ploeşti, nominally against ‘marshalling yards’. In fact the raids hit the oilfield, as intended, and in early May, Eaker gave approval for further attacks on Romanian oil production. Spaatz managed to persuade Eisenhower that German Air Force dependence on oil made it effectively a Pointblank target too and got a verbal assurance that on days when he was not attacking French targets, he could attack synthetic oil production.273 On 12 May Spaatz finally sent 886 bombers escorted by 735 fighters to attack six major oil plants across Germany. The force lost 46 bombers (32 of them from a bomber division whose escort failed to rendezvous correctly), but the swarms of American fighters destroyed 65 enemy aircraft for the loss of just seven planes. Ultra intelligence revealed the following day an urgent German order to move all available anti-aircraft artillery to protect the synthetic oil plants, including guns that until then had been guarding the aircraft industry. The next raid on 28 May was even more devastating, temporarily destroying output at the oil plants at Leuna and Pölitz in eastern Germany. Spaatz was proved right: the oil targets not only encouraged fierce defence by the German fighter force, but quickly proved debilitating to German forces reliant on a shrinking supply of fuel. Production of aviation fuel was 180,000 tons in March, but had fallen to 54,000 tons in June. So successful were the first attacks that on 4 June, two days before the invasion of France, Eisenhower gave formal approval for the oil offensive.274

  All the while Spaatz was driving the Eighth Air Force to impose insupportable levels of attrition on the enemy fighter force. When there were no bomber raids, Kepner was encouraged to send his long-range fighters in wide sweeps over German territory, attacking German airbases and seeking opportunities for combat. For bombing operations Spaatz chose long-distance targets which would compel German fighters to attack the bombers. In March he launched a number of major raids at aircraft production in Berlin, briefly overlapping with the battle Harris had been waging since November. The raids were among the costliest of the Pointblank campaign. On 6 March 730 bombers and 801 fighters left for the first raid on the capital. Fierce battles erupted over the city so that not only was the bombing inaccurate but the raid cost the Allies 75 bombers, though only 11 escorts were lost for the destruction of 43 German fighters. Raids continued throughout March and April, culminating in a final assault on Berlin on 29 April in which the bombing was ineffective and 63 bombers were lost. The German Air Force had reacted to the advent of the long-range escort fighter by creating large concentrations of up to 150 fighters – the ‘Big Wing’ used in the last stages of the Battle of Britain – which were designed to batter their way through to the bomber stream, or, when opportunity presented, to focus entirely on bombers whose escort had failed to materialize. The results for both sides were the highest losses of the war. In April the Eighth Air Force lost 422 heavy bombers, 25 per cent of the total; the German fighter force lost 43 per cent of its strength in the same month.275

  The arena of daylight air combat over Germany was among the harshest of the air war. American commanders expected a great deal of their crews. They were able to accept high losses only because a generous spring tide of aircraft and crew was now flowing across the Atlantic. For the German fighter force, high losses made it difficult to keep more than 500 serviceable fighters in the Reich Air Fleet at any one time. The result was that in air-to-air combat, fighter to fighter, the German force was completely outnumbered and the concentrations easily broken up. ‘An enormous number of us arrived, a crowd of 30, 50, sometimes 60 aircraft,’ a captured German fighter wing commander explained, ‘but each pilot simply attacked wildly at random. Result: each of them was shot down wildly at random.’276 The same officer described the decline in German pilot morale over the spring of 1944 as the order persisted to attack only the bombers, when their instinct was to protect themselves by engaging the enemy fighters first. One of Germany’s surviving pilots, Heinz Knocke, later published a vivid diary account of what air combat was like for German pilots in the spring of 1944:

  During the ensuing dogfight with the Thunderbolts my tail-plane was shot full of holes, and my engine and left wing were badly hit also. It is all I can do to limp home to our field … Immediately I order a reserve aircraft to be prepared for me to take off on a third mission. It is destroyed during a low-level strafing attack. Two of the mechanics are seriously wounded. No. 4 flight places one of its aircraft at my disposal … When we attempt to attack a formation of Liberators over Lüneberg Heath, we are taken by surprise by approximately forty Thunderbolts. In the ensuing dogfight our two wingmen are both shot down. After a wild chase right down to ground level the Commanding Officer and I finally escape with great difficulty.

  Knocke sat in the crew-room that evening with the one remaining pilot from his squadron.277 Declining morale was not di
fficult to explain with a one in two chance of surviving, repeated sorties each day, regular and unpredictable low-level attacks, irregular supplies and little chance of leave. Missions for German pilots became all but suicidal by the time of the Normandy invasion, when hundreds of fighter aircraft were sent west from Germany against odds even greater than the ones they had met in the spring.

  For American aircrews the situation was less rosy than German accounts might suggest. Morale dropped for them too during the spring offensive, partly because of high losses, partly because of the demands made on the crew from bad-weather flying. In March and April 1944, 89 bomber crews chose to fly to Swiss or Swedish bases for internment. Conditions were made worse by the decision to abandon automatic repatriation of crews to the United States after 25 missions in order to keep up the number of experienced aircrew available.278 German interrogation reports of crashed American aircrew found a deep fear of anti-aircraft fire, and a strong dislike of the order to conduct low-level attacks against German airfields because of light Flak and the tactic of stringing thick steel hawsers (Drahtsperre) across narrow valley approaches to slice into an attacking fighter.279 A major hazard was the return flight with battle damage and the difficulty of landing away from base. The crew of one B-24 ‘Liberator’ bomber, hit by anti-aircraft fire over Brussels, bailed out over Kent at the last moment before the damaged aircraft exploded: ‘I broke an ankle and incurred internal injuries,’ recalled the pilot. ‘The navigator hit a tree and broke his back … The flight engineer had a scalp injury from hitting his head on a rock. In all, we were pretty lucky.’280 The high casualty rate made it difficult for American aircrew to form any sense of whether they were winning the battle or not. In the period from January to the end of May 1944 the Eighth and Fifteenth air forces lost 2,605 bombers. Between March and May the American fighter forces lost 1,045 aircraft over Germany and France.

  Success only gradually became evident in May and June when Allied bomber losses suddenly fell sharply from the peak in April. By the summer the percentage of attacking bombers actually hit by enemy fighters fell from 3.7 per cent in March and April to only 0.4 per cent in July and August.281 The reason can be found in the corresponding German statistics. Between January and June, German aircraft losses on all fronts equalled 137 per cent of established strength, 6,259 lost in combat, 3,608 due to accidents, predominantly due to poor weather or pilot error. Despite fighting much of the time over German territory, the German Air Force also lost 2,262 pilots. Most of the losses occurred in Germany or on the Western Front in France and the Low Countries. In June 1944 losses totalled 3,534, only slightly less than the 3,626 aircraft of all types produced that month.282 This was an insupportable attrition cycle of both German material and manpower: even with the increases in fighter output that peaked later in the year, new production was sucked into a whirlpool of rapid destruction. Fighter pilots waited for the Me262 jet fighter, which first flew in March, in the hope that, produced in volume, it might turn the tide.

  The point at which Allied air supremacy was established in German air space is difficult to establish because of the continuous, fluid and incoherent nature of air combat. Some historians date it from the first attrition battles in March 1944, others from the early attacks on oil installations. The German head of the Historical Section of the German Air Force, Maj. General Hans-Detlef von Rohden, argued in a post-war assessment that Allied air supremacy over Germany had been achieved by the time of the Normandy invasion: ‘Germany had lost the struggle for Air Control.’283 A Joint Intelligence Committee evaluation in August 1944 concluded that the German Air Force ‘can no longer affect the military situation on any front’, which was not entirely true, but did reflect the exceptional degree of operational flexibility now available to American and, increasingly, British aircraft over Germany.284 No date is entirely satisfactory, but by June, when German reserves were sucked into the aerial maelstrom in France, the attrition cycle was, for the moment, complete. This was a situation the German Air Force wanted to reverse. In September 1944 a staff paper reflected on the lessons of the Battle of Britain: ‘We must try to achieve what England achieved in 1940.’285 The larger question posed by the ‘Battle of Germany’ is why the German Air Force failed where in 1940 the RAF – by a narrow margin – succeeded.

  There are certainly grounds for comparison. The German Air Force had a substantial fighter force with technology at the cutting edge, particularly after the Me109 fighter was refitted with the more powerful Daimler-Benz 605A engine; aircraft production was concentrated on an emergency fighter programme; a large pool of more than 2,000 fighter pilots were regularly available; there was a complex advance-warning system based on sophisticated radar equipment; and the organizational reforms during the winter of 1943–4 created a central control and communication system not unlike the centralized structure available to Hugh Dowding in 1940. The German Air Force had good intelligence warning of incoming attacks and a thorough understanding of enemy tactical weaknesses. Like Fighter Command, the men who fought in the German fighter force were defending their homeland and prepared to take high losses in doing so. Like their opponents in the Battle of Britain, the German Air Force leaders believed that success in the air was in 1944 ‘the most decisive precondition for victory’.286

  The comparison is nevertheless a superficial one. Germany’s strategic position in 1944 was very different from Britain’s in 1940, fighting on two major fronts in the Soviet Union and Italy and facing growing resistance in other areas of German-occupied Europe. The German priority was not simply to frustrate the Allied search for air superiority but to try to defend a fortress area in central Europe against overwhelming material superiority on all fronts. The strategic crisis explains the emergency programme of fighter production, like the British crisis of summer 1940. German fighter output reached its wartime peak between the last months of 1943 and the autumn of 1944, though this was achieved in an environment of heavy and continuous bombing. As a result, the gap between German fighter production and Anglo-American fighter output (produced in an almost entirely bomb-free environment) was not as significant as the gap in economic resources might suggest. British and American fighter output between January and June 1944 was 11,817; German production over the same six months was 9,489.287 In both cases this production was spread among a number of fighting fronts. Yet the Eighth Fighter Command had more than twice the number of fighters available when compared with the Reich Air Fleet, as well as additional support from RAF Fighter Command and the Ninth Tactical Air Force. In May 1944 the Reich Air Fleet had 437 serviceable fighters, the Eighth Air Force 1,174. The explanation lies partly in the difference between the two training regimes already noted, which put novice German pilots at a permanent disadvantage. There was also a major contrast in serviceability rates, which were higher for Allied aircraft once the American logistical system was working effectively. Under constant air attack and short of manpower, the production and distribution of spares and the supply of adequate ground engineering staff all declined in Germany. More than 9,000 German aircraft in 1944 were lost in transit from Allied air attack before they reached the combat squadrons.

  These contrasts were reflected in rates of operational readiness and rates of loss. During the Battle of Britain the peak loss rate for Fighter Command reached 25 per cent in September 1940. German Air Force monthly fighter losses were already 30 per cent of the force in January 1944 and more than 50 per cent by May (see Table 6.4). Numerical inferiority was then compounded with the demand that German fighters seek out the Allied bombers rather than fighters, which made them more vulnerable at the moment of attack, and by the decision to assemble large numbers of fighters together (like Douglas Bader’s ‘Big Wings’ in the Battle of Britain); this meant time lost in flight to assembly points and, for pilots who had flown on the Eastern Front in pairs or loose groups of four, a difficult adjustment to flying in larger formations.288 The RAF in 1940 avoided both these operational handicaps by using Spitfires a
gainst enemy fighters, Hurricanes against the bombers, while Dowding judiciously resisted the switch to ‘Big Wings’. The difference between the two sides was not simply a product of economic resources, as is usually argued, but stemmed from operational and tactical choices which rested in the end with those in command.

  Table 6.4: Comparative Fighter Statistics, German Air Force and Eight/Ninth US Air Forces, January–June 1944