1st March – 8th August 1943 – War in the Air – Part I – Bombing by Night
There were many things that had to come together to make D-Day possible. Men, materiel and a detailed knowledge of the terrain and defences in the chosen landing zone were all vitally important. Arguably however one thing that had the greatest potential to undo all this careful preparation would be a failure to secure air superiority, not only to protect the landing zones but also to allow allied bombers to provide the maximum possible support as the troops pressed inland. That the Luftwaffe had been able to maintain a high operational tempo during the Dieppe raid, and the fact that the latest German fighters had demonstrated a clear superiority over their opponents was alarming to say the least. Formulating a strategy to ensure this state of affairs was not repeated over Normandy was a complex business, even deciding what would constitute an adequate margin of superiority was a subject for debate. In an ideal world the Luftwaffe would be swept from the skies and the Allies would have complete mastery of the air. Achieving this ideal was considered impossible if the landing were to take place in the summer of 1943, indeed it was projected that it wouldn’t be possible to clear the Luftwaffe from the skies until the Spring of 1944 at the earliest. Given this the planners had to aim for a more limited objective, specifically the ability to suppress the Luftwaffe over the landing beaches and push far enough inland to allow for the creation of forward airbases that would allow for a high enough sortie rate to provide adequate air support [1].
One of the objectives of the Allies extensive deception operations was to have Luftwaffe resources scattered to Norway, the Mediterranean and the Balkans, diluting the fighter and bomber strength in northern France. This however was not enough for the D-Day planners, they wanted to force the Luftwaffe to strengthen its deployments in the Ruhr heartland of German industry and this could only be achieved by launching a bombing campaign aimed at crippling the Reich’s war production, which since this would disrupt aircraft production would produce a double benefit for Operation Millennium. This was no small challenge for the RAF and the USAAF, as the RAF’s early attempts at bombing Germany had been largely ineffectual beyond their morale boosting effects, owing to lacking both heavy bombers and the ability to deliver their bombs with any sort of accuracy [2].
By 1943 Bomber Command had large numbers of powerful four engine bombers at its disposal, in shape of the Stirling, which had a relatively short frontline career owing to the introduction of the Halifax and the legendary Lancaster Even with the introduction of aircraft that could deliver the weight of bombs required for a true strategic bombing campaign there were still issues with accuracy. These were addressed in part by the introduction of the Pathfinder squadrons, specialist units who would mark targets for the main bomber forces following behind. These squadrons had been formed into No. 8 (Pathfinder Force) Group in November 1942. They made extensive use of the De Havilland Mosquito and while they faced a steep learning curve by 1943 they were becoming highly effective, aided in no small part by the introduction of the H2S ground scanning radar at the beginning of January 1943. This not only allowed the Pathfinders to locate targets at night but also through cloud cover, allowing for all weather bombing. The Germans were unaware of this major step forward in RAF technology until a plane carrying an H2S set crashed on the night of 27th March 1943 and they were able to piece the set back together, provoking great alarm in the Luftwaffe and a hasty program to deploy the FuG 350 Naxos radar detector, which proved of only limited use [3].
An unexpected threat to the campaign against the Ruhr came from the head of Bomber Command, Arthur Harris. He was a firm believer that the war could be won from the air, despite years of evidence to the contrary provided by the Luftwaffe. Harris argued that his bombers could be put to better use attacking Berlin, breaking the morale of the German people by reducing the city to ruins. Perhaps if Millennium had been postponed until 1944 Harris might have gotten his way, but as it was this plan encountered fierce opposition from the other service chiefs and those entrusted with the detailed planning for Operation Millennium. They were deeply dubious about the theory behind the plan, and they warned that such a diversion of resources would risk tens of thousands of losses on D-Day if air superiority could not be achieved, as they believed the impact on Wehrmacht strength from bombing Berlin would be limited. It might force the Luftwaffe to redeploy assets to protect Berlin, but it would do little to disrupt the flow of guns, tanks and aircraft to arm the defences in France. Alanbrooke as CIGS was deeply unhappy with Harris, seeing in his attitude the embodiment of the lack of willingness to co-operate with ground forces that had cost the BEF so dear in 1940. Only when the RAF had been forced to direct their bombers at the German supply lines had they proven effective and the Ruhr was the hub of the German supply system in 1943, it should be bombed into oblivion in Alanbrooke’s opinion [4].
Harris’s stubborn resistance to the Ruhr campaign came in the wake of his attempt to block the creation of the Pathfinder squadrons and according to accounts in the diaries of Churchill and several senior RAF officers Harris came very close to being relieved of his duties in the spring of 1943. In the end he knuckled under, unwilling to see ‘his’ bomber crews placed under the command of a less capable officer, though this was simply postponing the inevitable for Harris. One after effect of this argument was that Harris was forced to commit to follow-up conventional raids in the event that Operation Chastise, better known as the Dambusters Raid, proved successful. This was another operation that Harris had been against mounting, and the success of the Dambusters in breaching the Möhne, Edersee, and Sorpe dams, on the night of 15th/16th May 1943 did nothing to strengthen his standing in the eyes of his superiors [5].
The attack caused massive disruption as the huge drop in water levels not only impacted the movement of goods along the industrial but cutting off the vital supply of hydroelectric power from the plants associated with the dams. The follow up raids, dropping conventional HE bombs, took place on the nights of June 16th and August 8th. These raids killed many of the thousands of workers that had been rushed into undertake repairs and destroyed much of the infrastructure put in place to carry out the work. These attacks meant that the dams were not fully restored to service until Christmas 1943, and the repairs were only completed because Harris finally got his wish and opened the ‘Battle of Berlin’ in September of 1943. This proved to be every bit as much a failure as the Luftwaffe’s effort to bomb Britain into submission three years earlier and the heavy losses taken during the campaign are credited with finally ending Harris’ tenure at Bomber Command. Nonetheless the damage to the dams was credited by some in the Nazi leadership with causing the fall in production of armaments that plagued the Luftwaffe and the Heer during the summer of 1943, with Albert Speer going so far as to claim that its impact was greater than all the other air raids on Germany in 1943 combined. With the Eastern Front still receiving the highest priority for equipment in the summer and autumn of 1943 this forced a scaling back in the build-up of defences in France and Normandy fell even lower in the priority list [6].
Many have argued that the relatively modest decline in industrial output in Germany in the latter half of 1943 is evidence that the Ruhr offensive was a waste of resources and that the men and materiel invested in Bomber Command could have been put to better use elsewhere. Such analyses fail to account for the factors that worked against the RAF bombing effort. New manufacturing capacity that had been laid down under Nazi economic programs in 1939-40 was finally coming online in 1943. At the same time there was a drive to rationalize the German aircraft industry, undertaken by the Luftwaffe and not the Speer ministry despite claims to the contrary, imposing greater control over the various companies and at the same time taking advantage of the increased productivity resulting from long series production. Manufacturers inevitably found ways to streamline the manufacture of a particular model of aircraft over time, what is commonly referred to as the learning curve. The downside of exploiting this experience was the necessity of freezing designs and keeping potentially obsolescent models in production to avoid the drop in output introducing new ones would engender. Before the Ruhr campaign was in full swing the men in charge of the Reich’s war economy were expecting a significant rise in production, thus the drop that actually occurred was a devastating blow to the Wehrmacht’s plans [7].
Assessing the impact of the Ruhr campaign one also has to take account of the resources diverted by the need to rebuild or defend Germany’s industrial heartland. Every 88mm cannon deployed in the anti-aircraft role was one less sitting in an emplacement in Normandy or fitted to the fearsome Tiger tank. Rebuilding dams and factories, or building new factories underground consumed raw materials and manpower that could have been used strengthening the Atlantic Wall. Consumed should be taken literally where the manpower is concerned as most of it was slave labour worked to death in appalling conditions. The Ruhr offensive not only degraded the flow of new aircraft to the Luftwaffe but equipment to the whole of the Wehrmacht and weakened the defences the troops coming ashore on D-Day would face, it was then a successful battle and one that in the end justified the losses suffered by Bomber Command in pressing it home night after night [8].
[1] So basically, they will have to live with air superiority, not supremacy. There are trades with an earlier D-Day.
[2] It was bad to say the least, it was estimated that they were lucky to drop bombs within 5 miles of their intended target.
[3] You may be able to tell I was recently reading up on the subject of electronic warfare in WWII.
[4] IOTL the RAF threw away their bombers on pointless missions and never touched the German supply columns. Here they hit them hard and Alanbrooke has not forgotten how important that was in securing the survival of the BEF.
[5] Yes, they got Sorpe as well this time, a pure butterfly effect sees 617 get just that bit luckier on the night.
[6] There is no ‘armaments miracle’ because this time the RAF aren’t wasting their time trying to turn Berlin into finer and finer rubble. The follow up raids were planned out but never executed because of Harris’ attitude to Chastise and the whole Ruhr campaign.
[7] You can tell I’m not a fan of the Speer as a miracle worker mythology, can’t you?
[8] The OTL campaign was also successful, the one ITTL is more so and its easier to see that success in the impact on the war.
