15 Wellingtons minelaying off Brest, Lorient and St-Nazaire without loss.
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11 Mosquitoes to north-west Germany. 9 aircraft attacked trains and rolling stock; 1 Mosquito lost.
Operational Statistics, 17/18 August to
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(125 days/nights)
Number of days with operations: 59
Number of nights with operations: 92
Number of daylight sorties: 948, from which 61 aircraft (6.4 percent) were lost
Number of night sorties: 10,256, from which 465 aircraft (4.5 percent) were lost
Total sorties: 11,204, from which 526 aircraft (4.7 percent) were lost
Approximate bomb tonnage in period: 15,421 tons
Averages per 24-hour period: 896 sorties, 42 aircraft lost, 123.4 tons of bombs dropped
Bremer Zeitung, as quoted in the Bremen Stadtarchiv report, p. 44.
Kiel im Luftkrieg 1939-1945, op. cit. p. 41.
As a 10-year-old boy, I was out in a field near my home in Boston, gathering blackberries, when the amazing and thrilling sight of nearly 100 Lancasters swept over my head carrying out one of those practice flights. - M.M.
Michael J. F. Bowyer provides a good description of the preparations for this raid and the outcome of it on pp. 263-83 of his book 2 Group R.A.F., op. cit.
Bomber Command had been struggling on now for more than three years, trying to keep its strength together in the face of urgent demands for help from other services and other fronts, trying to overcome the many obstacles to the successful bombing of German targets by night. But now, at the end of 1942, this steadfastness and patience was suddenly to be rewarded by a whole bonanza of improvements.
The first of these was called Oboe. This was a blind-bombing device fitted into an aircraft but controlled from ground stations in England. Two stations transmitted pulses which were picked up by the aircraft and retransmitted to the ground stations again. The aircraft receiving the Oboe signals used the pulses to keep itself on the correct track in order to pass over the target; the stations in England, by measuring the time taken to receive the pulses back again, calculated the aircraft's exact position and sent a short signal at the moment when its bombs should be released. An average bomb-aiming error of less than 300 yards could be achieved when all went well. The advantages of Oboe were self-evident, but there were three limitations. Firstly, it was a line-of-sight device whose signal could not be bent over the curvature of the earth; this limited the range of its use. Secondly, each station in England could only control six aircraft per hour, and as the maximum numbers of stations that could be used was three only eighteen aircraft per hour could thus use Oboe. Finally, the aircraft making the bomb run had to fly straight and level for several minutes and was likely to become an ideal target for German Flak or night fighters.
Although originally developed as a simple blind-bombing device - it had been tested as such by Stirlings against the German battle-cruisers of Brest - it was realized that the small number of Oboe aircraft that could be employed at any one time could best be used as marker aircraft in the Pathfinder Force. Eighteen aircraft per hour could not provide all the marking for a major raid but they could provide the primary marking for a raid, with non-Oboe Pathfinder aircraft of the heavy squadrons 'backing-up' with different coloured markers. In August 1942, a special Oboe marking squadron, 109 Squadron, commenced Oboe trials using Wellingtons, the type of aircraft originally intended for this work. A second squadron, No. 105, using Mosquitoes, was to be employed later. There was a delay but it was a delay which was to have a beneficial outcome. The new light bomber, the Mosquito, was found to have an operational ceiling of 30,000 feet or more, well above the altitude that could be reached by a Wellington or any other of Bomber Command's types. The Mosquito, as an Oboe bomber, would thus extend the range at which the device could be used and could cover all of the Ruhr area. The superior speed of the Mosquito would also reduce the time on the bomb run when it was vulnerable to the German defences.
The first Oboe Mosquitoes were ready for operations on
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. The way in which the device was introduced to operations is described in the relevant diary entries. On nights when the Oboe aircraft were not required for Pathfinder marking, they could be used in the bombing role; although they could never deliver a huge tonnage, their accuracy was amazing. Individual factory buildings could be attacked and were frequently hit. The Germans never managed to jam Oboe properly, one of their greatest failures of the bombing war.
Although the Oboe transmissions could be directed to intersect above any target within their range, most of the remainder of Germany would be free from the attentions of that device, at least until after the invasion of 1944 when mobile Oboe stations could move to France. But hard on the heels of Oboe came a second Bomber Command device which had no limitations to the range of its usefulness. This was H2S, the forerunner of the simple airborne ground-scanning radar set which most aircraft now have and whose presence and reliability are now taken so much for granted. Not so those early H2S sets which were delivered to Bomber Command at the end of 1942. A flickering, often indeterminate picture was all that the H2S operator in the bomber crew had, even when his set was working properly. Coastlines and wide rivers could usually be distinguished, city outlines sometimes, other features not often. But the device was a boon to a force which until then had to rely on dead-reckoning navigation and the Gee device, which the Germans were now jamming regularly from the North Sea onwards. In the hands of a skilled operator, H2S could be an invaluable navigational aid and could even be used as a rough-and-ready aiming device when no better means were available, not as accurate as Oboe but of unlimited range because the set was carried in the aircraft.
The Pathfinder Force received the first H2S sets to be issued to Bomber Command. Thirteen Stirlings of 7 Squadron and ten Halifaxes of 35 Squadron were ready for the first operational use by the end of January 1943. H2S would enable the leading Pathfinder crews to find the target city more quickly and drop illuminating flares or markers. Every Pathfinder aircraft would have its own H2S set in 1943 and by early 1944 there would be enough sets for the whole of the Main Force.
To round off these two major technological advances, we should mention the first developments in Bomber Command to counter the Germans' own radar and radio devices. Mandrel was a ground device in England for jamming the Germans' own ground radar stations, the same stations which directed the German night fighters in controlled interceptions. Tinsel was a small microphone near one of an R.A.F. bomber's engines which could be tuned by the aircraft's wireless operator to any frequency on which he heard instructions being broadcast to German pilots. These two devices both became operational in December 1942, the same month in which Oboe was first used. Mandrel and Tinsel did not cause major disruptions to the German night-fighter system - they were a minor but steady irritant - but they were the forerunners of a vast radio-countermeasures effort eventually mounted in Bomber Command. Everything that could help reduce casualties was needed. The recent period had seen the highest casualty rates so far in the war; fortunately the coming period would show an improvement, partly because greater numbers of bombers were starting to swamp the German night-fighter box system and partly because Bomber Command - with the help of its blind-marking and bombing devices Oboe and H2S - was beginning to restrict its operations on moonlight nights.
The scientists and engineers were still not finished. The initial operations of the Pathfinder Force had been hampered by lack of an effective 'marker bomb'. Now a purpose-built marker was produced for Pathfinder use, most of the work being done by the pre-war firework industry. A standard Pathfinder marker called the 'target indicator' was now produced and it would last until the end of the war. It was a 250-pound bomb casing packed with pyrotechnic candles which could be ejected at various heights by a barometric fuze and cascade slowly to the ground in a mass of bright colour; red, green and yellow were the standard Pathfinder variations. The target indicator was reliable, vivid, distinctive and not easily copied by German decoys; around it, the Pathfinders developed marking techniques which would also stand until the end of the war. The first target indicators were ready for use in mid-January 1943. So, after years of operating with virtually no technical aids, Bomber Command received Oboe, H2S, the target-indicator bomb and its first radio-counter-measures devices all in less than two months.
And the story of Bomber Command's resurgence did not end with that catalogue of technology. The force of aircraft available for operations was at last increasing in number. The days were gone when new squadrons were formed and trained, only to be sent away to Coastal Command or the Middle East. The new four-engined types were pouring out of the factories. 1 Group had become the second group to start equipping with Lancasters, after a brief false start with Halifaxes. 3 Group was now an almost entirely Stirling force; this group had only one Wellington squadron left. The Halifax had overcome most of its early problems and three quarters of the aircraft in 4 Group were now of this type, the remainder of its aircraft being Wellingtons. 5 Group was entirely equipped with the Lancaster and was now capable of delivering a greater tonnage of bombs in one night than the whole of Bomber Command of a year earlier.
There was a completely new group - No. 6 (Canadian) Group - based in North Yorkshire and Durham. This group had existed on paper since October 1942 but did not become operational until New Year's Day of 1943. In the interval, 4 Group had performed a valuable task in gathering together the existing Canadian squadrons in Bomber Command and forming further new squadrons. Thus nine squadrons - six of Wellingtons and three of Halifaxes - were handed over to 6 Group, most of them ready for immediate operations. Air Vice-Marshal G. E. Brooks, a Canadian officer, was the first commander, with his headquarters at Allerton Park Castle near Knares-borough. The Canadian Government would pay the full costs of the group for the remainder of the war and nearly all the ground staff and many of the aircrew were Canadians. (Canadians also served in other groups; there was never any completely national unit in Bomber Command.)
The Pathfinders were also promoted to group status, becoming No. 8 Group on
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DUISBURG
232 aircraft - 111 Lancasters, 56 Halifaxes, 39 Wellingtons, 26 Stirlings. 12 aircraft - 6 Lancasters, 4 Wellingtons, 2 Halifaxes - lost, 5.2 percent of the force.
The bombing force found that the target area was clear and claimed much damage. It has not been possible to obtain a report from Duisburg.
LUTTERADE OBOE TRIAL
6 Mosquitoes of 109 Squadron were dispatched to bomb a power-station at Lutterade, a small town in Holland near the German frontier. The first Oboe-aimed bombs were dropped by Squadron Leader H. E. Bufton and his navigator Flight Lieutenant E. L. Ifould. 2 other crews bombed on Oboe but the equipment in the remaining 3 aircraft did not function properly and they bombed elsewhere. The Mosquitoes all returned safely.
Daylight photographs taken after the raid showed so many old bomb craters from an earlier raid when the Pathfinder mistook Lutterade for Aachen that it was impossible to identify the Oboe results reliably. A local report, however, states that 9 bombs fell together in open ground 2 km from the power-station, fortunately just missing a large area of housing situated between the power-station and the place where the bombs fell. It is surprising that the target for this first Oboe trial should have been a location in friendly Holland which had so much housing near by.
4 O.T.U. Wellingtons on leaflet flights to France without loss.
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to S March 1943
(75 days/nights)
Number of days with operations: 38
Number of nights with operations: 58
Number of daylight sorties: 923, from which 25 aircraft (2.7 percent) were lost
Number of night sorties: 9,057, from which 251 aircraft (2.8 percent) were lost
Total sorties: 9,980 sorties, from which 276 aircraft (2.8 percent) were lost
Approximate bomb tonnage in period: 17,834 tons
Averages per 24-hour period: 133.1 sorties, 3.7 aircraft lost, 237.8 tons of bombs dropped
Official History, Vol. IV, pp. 152-3.
Feuersturm ber Hamburg, op. cit., pp. 157-8.
Sir Arthur Harris called the period from the spring of 1943 until the spring of 1944 his 'main offensive'. He had steered Bomber Command through the recent winter with great skill, recognizing that the time was not yet ripe for an all-out effort, conserving and building up his force, yet constantly experimenting with new tactics and the introduction of new devices. But now, in the early March of 1943, all was ready for a sustained and major effort against Germany and Harris decided that he would commence what he called at the time the Battle of the Ruhr. History would confirm the suitability of that title.
The 'battle' concept was a reflection of the principle of concentration, with the main strength of Bomber Command's night force being directed as much as was tactically possible against one target system until that target system was destroyed. It is probable that Harris had Berlin in mind as his ultimate battle; to destroy Berlin would surely force Germany out of the war. But Harris knew that Berlin was too difficult a target for Bomber Command at that time. The vital considerations were the need for further development of target-finding methods and the duration of darkness. Berlin required the increasing nights of autumn and winter, not the shortening ones of the coming spring. The Ruhr was the logical place to fight Bomber Command's first pitched battle. The whole of the Ruhr area, with its huge spread of industrial cities, was within range of the blind-marking device Oboe and any target in that area could easily be reached in the shorter nights of spring and summer.
There were two aspects of the coming offensive which should be mentioned. Firstly, none of Bomber Command's battles could ever concentrate exclusively on one target area. Such a course of action would have allowed the Germans to concentrate their night-fighter and Flak defences and defeat the bombers. The main Battle of the Ruhr would last for four months, during which forty-three major raids were mounted. Two thirds of these raids were on the Ruhr but the remainder were scattered across widely spread areas of Europe - to Stettin on the Baltic, to Pilsen in Czechoslovakia, to Munich deep in Bavaria, to Turin in Italy. It was a good example of the flexibility of air power and the Germans were never allowed to concentrate all their defences at the Ruhr. The second point, however, is that the Flak and searchlight defences around the Ruhr cities were already the most powerful in Germany and the night-fighter units manning the boxes on the routes between the coast of Europe and the Ruhr were already the most experienced and best equipped in the Luftwaffe. Despite the dispatch of some raids to distant points, the Germans were bound to reinforce both their ground and air defences around the Ruhr as the battle developed. The coming period was going to be a major test between the skill, determination and courage of the participants. On the one side stood the commander-in-chief of Bomber Command and the men of his squadrons; on the other side stood the German city civilians and the personnel of the Flak and night-fighter units which were attempting to defend the cities. The levels of death and destruction were about to mount dramatically.
Two major factors were on the side of the British. The first was the continuing increase in Bomber Command's striking power. At the opening of the Battle of the Ruhr there were nearly 600 bombers available and, at the peak of the battle, towards the end of May, the city of Dortmund would be attacked by more than 800 aircraft. Four fifths of these were four-engined aircraft. One set of statistics can illustrate this point. On the
