The United States Strategic Bombing Survey (USSBS) was a written report created by a board of experts assembled to produce an impartial assessment of the effects of the Anglo-American strategic bombing of Nazi Germany during the European theatre of World War II. After publishing the report in 1945, the Survey members then turned their attention to the war efforts against Imperial Japan during the Pacific War, including a separate section on the recent use of the atomic bomb in attacks on two Japanese cities.
In total, the reports contained 208 volumes for Europe and another 108 for the Pacific, comprising thousands of pages. The reports' conclusions were generally favorable about the contributions of Allied strategic bombing towards victory.
The survey said of Allied airpower that it "was decisive in the war in Western Europe. Hindsight inevitably suggests that it might have been employed differently or better in some respects. Nevertheless, it was decisive. In the air, its victory was complete. At sea, its contribution, combined with naval power, brought an end to the enemy's greatest naval threat-the U-boat; on land, it helped turn the tide overwhelmingly in favor of Allied ground forces"USSBS p37
A majority of the Survey's members were civilians in positions of influence on the various committees of the survey. Only one position of some influence was given to a prominent military officer, USAAF General Orvil A. Anderson (who had been in the Air War Plans Division) and that only in an advisory capacity. Anderson was the only one on the survey board who knew about procedures of strategic bombing as Jimmy Doolittle's former deputy commander of operations. While the Board was not associated with any branch of the military, it was established by General Hap Arnold (chief of the USAF) along with Carl Spaatz (commander of Strategic Air Forces in Europe). Failing to obtain the prominent public figure he had hoped for, Arnold settled for Franklin D'Olier.
Background The strategic bombing effort against Germany had begun at the start of the war with British attacks on German naval facilities. After heavy losses in daylight raids, RAF Bomber Command moved to night attacks for protection from German fighter defences. The Butt report identified that attacks on specific targets were inaccurate due to navigational and target identification issues. Bomber Command reorganised its efforts and targeted German industrial locations in general rather than aiming for any specific factory or industry under the Area Bombing directive. At the same time it invested in navigational aids and target marking. The total bomber force increased until the RAF was able to send 500 to 800 bombers against a single target city while still able to carry out minor raids and diversions against other areas. While in 1941 the RAF dropped about 46,000 tons of bombs, in 1944 it dropped 676,000 tons.USSBS p9
The USAAF entered the strategic bombing campaign with the intention of targeting specific industrial locations and to achieve precision bombing the attacks needed to be made by daylight. Formations of bombers flew in a mutually self-defensive "combat box" where their many machine guns would be sufficient to drive off or bring down enemy fighters. In practice due to many factors including the weather bombing accuracy fell short - around 20% of bombs fell within the required 1000 ft of the aiming point.USSBS, p13
The 1943 Casablanca conference led to the Allied strategic bombing organisation: the USAAF would be working together with the RAF in the Combined Bomber offensive concentrating on particular areas of German industry but in such a way as their commanders interpreted their instructions. In 1942 and early 1943 the US 8th Air Force based in UK had limited itself to raids close to base as it built up its strength, and developed tactics. A second strategic force, the 15th Air Force was created in the Mediterranean. Two further air forces, the Ninth Air Force in Western Europe and Twelfth Air Force in Mediterranean were focused on tactical operations in support of land forces.
The Allied strategy was to win the war by a land war in Europe rather than delivering a knock out blow by airpower alone, and the bombing strategy was in support of that. Over the course of the war, the focus of the Combined Bomber Offensive changed. As Germany was reliant on imported fuel and the synthetic generation of fuel from coal, attacks on such facilities were ordered. While some attacks were successful, the aircraft and crew losses were far beyond what could be sustained and further attacks were limited to within range of supporting fighters In late 1943, the Pointblank directive specified the importance of reducing the ability of the Luftwaffe to influence the outcome of the cross-Channel invasion of France planned for mid-1944 by attacking the production of German fighter aircraft. Changes in tactics and availability of longer ranged fighters meant that the active Luftwaffe force was significantly diminished in early 1944 and the majority of the bombing offensive was directed instead against transport routes to prevent reinforcement of the defences there.
Europe The Survey team was formed on 3 November 1944 by Secretary of War Henry L. Stimson in response to a directive by President Roosevelt.Summary (1945), Forward The headquarters was in Teddington, England, while its teams assessed the damage that had been done targets as the allied armies took control of them. German records were analysed for information and Germans interrogated including the remaining senior officials in the Nazi regime.USSBS (Europe) p 3 The survey was not able to assess the effects in Soviet controlled areas.
The sociologist Charles Fritz was part of the survey team before going on to become a significant theorist in disaster research. The Survey was tasked with producing an impartial report on the effects of the bombing against Nazi Germany, in order to:
aid the upcoming campaign against the Japanese home islands, establish a basis for evaluating the importance and potentialities of air power as an instrument of military strategy, provide data for planning the future development of the United States armed forces, and determine future economic policies with respect to the national defense.
The report, along with some 200 supporting documents, was dated 30 September 1945. However it was not publicly released until 30 October 1945. The major conclusion of the report was that strategic bombing, particularly the destruction of the oil industry and truck manufacturing, had greatly contributed to the success of the Allies in World War II. However, despite the overall contribution of the bombing, the survey concluded that the impact of strategic bombing could not be separated from the general collapse of Germany in 1945.USSBS p 11
The survey notes the effects on the German population: 3,600,000 "dwelling units", approximately 20% of total housing stock were "destroyed or heavily damaged" with an estimated 300,000 civilians killed and a further 780,000 wounded. About seven and half million were left homeless. The survey found that German morale deteriorated after attacks night bombing having a greater effect but although dissatisfaction with the war increased, under the German police state the will or means to oppose the leadership was absent.
In attacks on urban areas incendiary bombs, were ton for ton, four to five times as destructive as high explosive. German fire defences were inadequate and in cases of fire storms ineffective. While cities were provided with very strong bunkers (resistant to direct hits) as air raid shelters, there was insufficient capacity (enough for 8 million) and casualties outside the shelters among those sheltering in basements and cellars was high.
Successes The Survey noted several successes against crucial industrial areas: "The Attack on Oil". This section of the USSBS presents the statistics for the Oil Plan portion of the bombing campaign against petroleum, oil, and lubrication (POL) products, particularly regarding the Leuna complex (largest of the plants) that produced a notable portion of the synthetic oil which as a result of bombing averaged an output of 9% of capacity from mid 1944 The survey reported the Nazi Germany position that the attacks were "catastrophic" with Speer writing on 30 June that aviation fuel was reduced by 90%. An attempt at rebuilding and dispersing production employing a workforce of 350,000 men was made but incomplete by the end of the war USSBS p 21 From May 1944 production was less than consumption and reserves were drained. The Ardennes offensive of December 1944 was predicated on capturing Allied fuel to sustain it. The synthetic oil plants were also a source of nitrogen for German agriculture and this was heavily cut back (at first to 50%, then 25%, then altogether) in order to release nitrates for explosive production. Ammunition: Production fell markedly in 1944 and the arms industry shipped bombs and shells packed partly with rock salt, as Germany ran out of nitrate, a vital ingredient and methanol (another product of fuel synthesis). Finally, Albert Speer, head of the Nazi economy, shifted the last nitrogen from the war effort to agriculture because he believed the war was lost and next year's crops were more important. Truck manufacturing facilities were extensively bombed. Of the top three producers, Opel at Brandenburg, was completely shut down in one raid in August 1944, and never recovered. Daimler-Benz was decimated a month later. The third largest producer, Ford's German subsidiary at Cologne was never directly attacked, but production was sharply cut during the same period by elimination of its component supplies and the bombing of its power sources. By December 1944, production of trucks was reduced to 35 percent of the average for the first half of the year. After the war, General Motors, owner of Opel, successfully sued the US government for $32 million in damages sustained to its German plants (Ford Motor Company also demanded compensation from the U.S. government for "losses" due to bomb damage to its German subsidiary). U-boat (submarine) manufacturing was halted in early 1945. Disruption of transportation: German transport was dependent on the Reichsbahn railways and on waterways. Bombing from September disrupted movement of material and products. In February 1945 the Ruhr was completely isolated from supplies of coal.
Failures The Survey also noted a number of failed or outcomes of limited success:
Aviation production: "In 1944 the German air force is reported to have accepted a total of 39,807 aircraft of all types -- compared with 8,295 in 1939, or 15,596 in 1942 before the plants suffered any attack." According to the report, almost none of the aircraft produced in 1944 were used in combat and some may have been imaginary. Armoured fighting vehicle production "reached its wartime peak in December 1944, when 1,854 tanks and armoured vehicles were produced. This industry continued to have relatively high production through February 1945, but the effect [of bombing] again may have been to cause the industry to fall short of achievable production". Ball bearings: "There is no evidence that the attacks on the ball-bearing industry had any measurable effect on essential war production." "Secondary Campaigns" (Operation Chastise against German dams and Operation Crossbow against V-weapons sites): "The bombing of the launching sites being prepared for the V weapons delayed the use of V-1 appreciably. The attacks on the V-weapon experimental station at Peenemunde, however, were not effective; V-1 was already in production near Kassel and V-2 production had been moved to an underground plant. The breaking of the Mohne and the Eder dams, though the cost was small, also had limited effect."