The Royal Air Force's (RAF) bombing offensive against Nazi Germany was one of the longest, most expensive and controversial of the Allied campaigns during the Second World War. Its aim was to severely weaken Germany's ability to fight, which was central to the Allies' strategy for winning the war.
RAF Bomber Command was created in 1936 and comprised the RAF's light and heavy bomber squadrons. Over the course of the war, it developed from a limited and relatively ineffective force into a weapon of immense destructive power. It received a major slice of Britain's economic and technological resources, and many of its brightest and best young men.
In 1939 RAF Bomber Command had 23 operational bomber squadrons, with 280 aircraft. This modest force gave Britain the means to immediately strike back at Nazi Germany, but only against strictly military targets at first. Early raids against warships and airfields were conducted in daylight, but bomber aircraft were easy targets for enemy fighters and losses were heavy. The bombers also flew over Germany at night, but dropped only propaganda leaflets.
Pictured here are Vickers Wellingtons of No. 9 Squadron shortly before the outbreak of war. The belief that bombers could defend themselves in daylight if they flew in close formation was soon proved wrong. On 18 December 1939, 12 out of 22 Wellingtons were shot down by German fighters on a raid against shipping off Wilhelmshaven.
In 1940, after Hitler's invasion of France, the RAF began a night-time bombing campaign against German industry, especially synthetic oil production. But plans to hit specific factories proved impractical as crews invariably failed to identify individual factories and refineries in the darkness. Their bombs were scattered far and wide. Bomber Command lacked the strength at this stage to do any serious damage.
Pictured here is a Bristol Blenheims of No. 110 Squadron in June 1940. The Bristol Blenheim was Bomber Command's principal light bomber in the early years of the war. By the time this photograph was taken, Bomber Command had switched to night bombing, but 2 Group was tasked to continue low-level daylight operations with a variety of aircraft until May 1943.
In 1941 Bomber Command grew in strength, but navigation over blacked-out Europe was still a major problem. Setbacks in the Battle of the Atlantic meant a major effort was needed against German warships and U-boats. German night-fighters and anti-aircraft guns were becoming more effective. Heavy losses caused a slump in morale.
Pictured here is a Short Stirling of 7 Squadron at Newmarket Heath in Suffolk, July 1941. The Stirling was the first of the RAF's four-engine bombers to enter service. It could not fly as high as the Halifax or Lancaster, and so was more vulnerable to anti-aircraft fire. Stirlings were withdrawn from bomber operations in November 1943.
In 1942 Bomber Command received a new aircraft – the Avro Lancaster – and a new leader – Air Chief Marshal Sir Arthur Harris. Accepting that precision bombing was proving impossible, the War Cabinet sanctioned 'area bombing' – the targeting of whole cities to destroy both factories and their workers. It was judged necessary to defeat an enemy that seemed on the brink of victory. Harris believed it could win the war and gained much public support when he sent 1,000 bombers against Cologne.
Pictured here is an Avro Lancaster of No. 83 Squadron in June 1942. By this date seven squadrons were equipped with the new bomber, which went on to become the most important and numerous of Bomber Command's 'heavies'.
In 1943 new tactics and technology enabled crews to find and hit their targets with increasing precision. An elite Pathfinder Force guided the bombers using coloured marker flares. Major attacks were launched against Germany's industrial heart in the Ruhr valley. Hamburg was devastated by a firestorm. But attempts to knock out Berlin failed. By now the United States Eighth Air Force had joined the RAF in a 'round the clock' offensive.
In this photograph, a Lancaster is silhouetted against the fires of Hanover on the night of 8-9 October 1943. It was one of 504 Bomber Command aircraft sent on this raid, during which 27 bombers and their crews were lost. Clear weather and accurate marking made for a concentrated attack and the city was badly damaged. 1,200 people on the ground were killed.
In 1944 the combined Allied bomber force began to overwhelm the Germans. American escort fighters shot the Luftwaffe out of the sky. A successful offensive was launched against Germany's vulnerable fuel supplies. Bombers also flew in support of D-Day, softening up coastal defences and hitting railways to block German reinforcements. Enemy troops were carpet bombed in advance of major Allied ground offensives. Harris continued his city attacks, still convinced they would prove decisive.
Pictured here are Boeing B-17s of the United States Army Air Forces (USAAF) on a raid against the Focke-Wulf factory at Marienburg, near Danzig, on 9 October 1944. The Americans joined Bomber Command's air offensive in 1942. During 1943, American bombers had suffered unsustainable losses in their daylight attacks against the German aircraft industry. But in the spring of 1944 Allied escort fighters gained superiority over the Luftwaffe, which meant Bomber Command could also begin operating in daylight again.
In 1945 the bomber offensive reached the peak of its destruction. The RAF alone now had 108 squadrons with over 1,500 aircraft. Raids against oil and communications proved the most effective. Starved of fuel, the German military machine ground to a halt. Industrial cities were pounded to rubble. A record 4,851 tons of bombs were dropped on Dortmund in a single night. Enemy production was massively disrupted, and in some places ceased. Controversially, locations so far untouched were razed to the ground as they rose to the top of the target list. Dresden, Pforzheim and others were consumed by fire. With the war over, the Americans managed to distance themselves from the public and political unease caused by bombing these cities. But RAF Bomber Command, despite its major contribution to the Allied victory and the death of over 55,000 aircrew, remains mired in controversy to the present day.
This photograph shows the ruins of Hamburg in May 1945. Hamburg suffered over 70 raids during the war, most of them directed at its shipyards, U-boat pens and oil refineries. By the war's end most of Germany's industrial cities had been reduced to a similar state by the RAF and US bomber forces.