95: Axis of Airpower


The Italian and German air forces enter the war at very different points of their interwar evolution. One of was fading from power, the other was at its zenith.


  • British Intelligence on the German Air Force and Aircraft Industry, 1933-1939 by Wesley K. Wark
  • Case Studies in the Development of Close Air Support Edited by Benjamin Franklin Cooling
  • The Development of the Italian Air Force Prior to World War II by James J. Sadkovich
  • The Strategic Dream: French Air Doctrine in the Inter-War Period, 1919-39 by Robert J. Young
  • History and Evolution of Close Air Support: World War I to the Korean War by Michael J. Chandler
  • The Origins of American Airpower Theory by James R. Cody
  • The Price of Air Power: Technological Change, Industrial Policy, and Military Aircraft Contracts in the Era of British Rearmament, 1935-39 by Sebastian Ritchie
  • Airpower and the Cult of the Offensive: Royal Air Force, 1918-1938 by John R. Carter
  • The Royal Air Force, Air Power and British Foreign Policy, 1932-37 by Malcolm Smith
  • Strategy for Victory: The Development of British Tactical Air Power, 1919-1943 by David Ian Hall
  • The War in the Air 1914-1994 Edited by Alan Stephens
  • Why Air Forces Fail: The Anatomy of Defeat Edited by Robin Higham and Stephen J. Harris
  • The Air Panic of 1935: British Press Opinion between Disarmament and Rearmament by Brett Holman
  • Trenchard and “Morale Bombing”: The Evolution of Royal Air Force Before World War II by Phillip S. Meilinger
  • The Heavy Bomber at its Inception by Jerry Hendrix and James Price
  • Rhetoric and Reality in Air Warfare: The Evolution of British and American Ideas about Strategic Bombing, 1941-1945 by Tami Davis Biddle
  • Incubate Innovation: Aviation Lessons from the Interwar Period by Lieutenant Philip d. Mayer
  • Strategy for Defeat the Luftwaffe 1933-1945 by Williamson Murray
  • Military Innovation in the Interwar Period Edited by Williamson Murray and Allan R. Millett
  • The Paths of Heaven: The Evolution of Airpower Theory by The School of Advanced Airpower Studies


Hello everyone and welcome to History of the Second World War Episode 95 - Interwar Airpower Pt. 4 - Axis of Airpower. This week a bit thank you goes out to Sean, Josh, Stuart, and Alain for choosing to support the podcast by becoming members. They now get access to ad free versions of all of the podcast’s episodes plus special Member only episodes roughly every month. Head on over to historyofthesecondworldwar.com/members to find out more. I also wanted to let you know that on June 25th I will be speaking at the Intelligent Speech 2022 conference. This is a fully online event where I will be joined by over 35 other historians and history podcasters to discuss a wide range of topics. I will be giving a talk entitled “The Correct Wrong Choice: The Interwar Years and Results Based Analysis” in which I will chat a bit about how we should approach discussions about events that happen before major events like the Second World War. During the session there will be an opportunity for some Q&A, which was a ton of fun last year. If you register before June 1st you can get the Early Bird special for just $20, and you can use my code Second, that is just the word Second, at checkout so that they know that you heard about it here. You can find the link in the show notes, or you can head over to intelligentspeechconference.com to register or to find out more. Last episode we discussed some of the Air Forces around Europe, to look at what they were trying to accomplish during the interwar years and some of the challenges that they faced in actually achieving those goals. This week we will continue our tour with 2 more Air Forces: Germany’s Luftwaffe and Italy’s Regia Aeronautica. Now the obvious reason that these two nations are grouped together in this episode would be that they would be allies during the Second World War. This alliance would begin in the prewar years as the two nations moved into closer and closer orbits due to the similarities in their overall political structure and their ultimate goals, which for both nations involved geographic expansion. And while this is one of the reasons that they are both in this episode, another is how they both would evolve during the 1930s. During the 1920s the Italian Regia Aeronautica would be considered either the second, or the first, most powerful air force in the world. This strength then carried over into the 1930s, with the Italian strength in the air serving it well during the diplomatic discussions that would occur in the middle of the 1930s. However, as the other nations of Europe began their serious rearmament campaigns, Italy would be unable to keep pace not just due to industrial issues, but also due to how Italy chose to spend its resources after 1935. It would be replaced at the top of the airpower list by Germany and its newly created Luftwaffe, which would then go on to expand and increase its strength until the start of the war. The war would then end up happening at basically exactly the correct time for the Luftwaffe, because it was in the last months before the war that it was about to be overtaken by a new challenger, just as it had overtaken the Italians. That new challenger was Britain’s Royal Air Force, which we will discuss next episode. The Luftwaffe was in a better position than the Italian Air Force because the war would start before it could really fall behind, which set the Luftwaffe up for a really impressive first 2 years of the war. There were long term problems that set it up for challenges after those first two years, but at the beginning things would go quite well. We will discuss some of the events in the last years before the war before turning to our last topic today, which will be a dive into what the British knew or guessed about the Luftwaffe and how it affected their decision making process. Investigating intelligence reports from one nation about another is always interesting, and often very important when trying to understand why nations reacted the way they did to events like the build up of the Luftwaffe.

Throughout the 1920s the Italian fascist regime under Mussolini would spend a large amount of money on the Regia Aeronautica, which is Italian for Royal Air Force. At the same time they would also make it an independent military arm, which gave it relative autonomy to develop along its own route. By the middle of the 1920s the Italians would have the second largest air force in the world, behind only that of the French which were in many ways still coasting off of its First World War strength. Italy would continue to invest heavily in its Air Force throughout the 1920s and into the 1930s, with Italy spending around a quarter of its total military budget on its air force from 1933 to 1940. This provided plenty of funds for expansion, but they would be used in a way that would make them less impactful once the war started in 1939 and then Italy joined in 1940. The number one problem was that so much of this spending on the Air Force went into building planes and supporting operations in Ethiopia and Spain. These operations provided important political benefits to Mussolini, and they had possible payoffs in the future. Taking control of Ethiopia opened the possibility of paying off in revenue through expansion in Italian control. Helping Franco in Spain had the possibility of giving Italy an ally in the Mediterranean, and one that would be very nicely placed to interdict British forces should war ever start between Italy and Britain. The problem was that neither of these possibilities actually happened. In Africa the return on the investments made in capturing Ethiopia were negligible before the start of the war. In Spain, even after the Civil War was complete, Franco was in too weak of a position to commit to an alliance with Italy or to be able to provide meaningful assistance to Italy. The fact neither of these endeavors paid off in the way that was hoped was problematic due to how much Italy had invested not just monetarily but also the dedication of production capacity. Aircraft production capacity in Italy was limited, and so every aircraft that was created for service in Spain or Africa, or as a replacement for one lost in those theaters, was one less plane that could be provided to the Regia Aeronautica for other purposes. It also reduced the ability of manufacturers to focus on the next generation of aircraft as they focused on known models that were needed immediately for service. These production capacity problems were exacerbated by the drive to push aircraft technology forward to match that of other nations, with the shift to all metal monoplanes proving to be a shift that was difficult for the Italian manufacturers in the late 1930s. The African and Spanish adventures also strained other crucial supplies, with there being growing concerns about the availability of fuel and lubricant oil, which would be a major problem when the war started which removed the possibility of importing the resources from abroad.

Those were some of the problems faced by the Regia Aeronautica in the 1930s, but their investments in their aircraft did pay dividends. When the war began in Europe the Italians would be able to must 4,200 aircraft of all types within their Air Force, although there were of course far fewer that were capable of being useful within a combat zone. But even beyond this, the top level number also hid several important weaknesses. The first was that many of the aircraft were older models, with more than half being generally seen as obsolescent at best. Just like in ever other nation at this time, not every aircraft design that would be drawn up for Italian aircraft would be successful, when pushing for new designs sometimes things just did not go well. The Italians would have particular problems with their next generation of fighters, and then producing them in a large enough quantity, and this meant that the bulk of their fighters squadrons were on the previous generation at the start of the war. There were still some very workable fighters, with the Macchi C.200 and the Fiat G.50 being two examples. These aircraft were roughly equivalent to the fighters that other nations would have near the beginning of the war, for example the Hawker Hurricane, which was serviceable at the start of the war but was quickly outpaced by further advances in fighter technology. The Italians would never be able to really execute on the next generation, and the designs for the next generation of aircraft would not really get started until 1938 before encountering problems. These issues started almost immediately, with a delay being forced into the schedule just to allow more companies to submit proposals. And then when 4 prototypes were selected, instead of rapidly pushing to select one to focus on, effort was instead spent on all four, which would delay selection. There were similar challenges in many other nations that tried to introduce new aircraft during the war, with there always being a balance between designing, developing, and testing new innovations with the immediate demands of the ongoing conflict. While attempting to modernize its squadrons, the commander of the Italian Air Force would change to General Francesco Pricolo in late 1939. Among the 4,200 aircraft that were available, he estimated that only 647 bombers and 191 fighters were actually fully operational and were modern enough to be useful against a strong enemy. This was slightly more pessimistic than some other estimates of Italian strength, but may have been more correct. Pricolo would also be a real believer in placing great emphasis on strategic bombing, views that mimiced those that we have discussed in many air leaders in the previous episodes, with all other air power activities seen as secondary to the bombing mission, and he would treat them as such. the challenge was that Italy simply did not have the aircraft to launch any kind of strategic bombing campaign. Its largest bombers were classified as medium bombers, and by the time that Italy had entered the war they did not have the range to hit the kind of targets best suited for strategic area bombing. Without the ability to launch these strategic campaigns they would be far more focused on action closer to the front. But really, the focus on what aircraft the Italians had, or what they planned to do with them, was of secondary importance to the problems in Italian industry. They would always be at a disadvantage after the start o the war, both quantitatively and qualitatively they simply could not keep up with the demands placed upon them by the innovation and production of their enemies. And this was true even before the arrival of the Americans and their seemingly infinite production resources.

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Back in episode 83 we spent an entire episode on the evolution of the Luftwaffe, touching on topics like the Luftwaffe’s emphasis on dive bombing, its experiences in Spain, and some of the challenges it would face as it tried to rapidly expand during the 1930s. As a review, the Luftwaffe would be created shortly after Hitler came to power, although it would not be publicly announced and acknowledged until February 1935. The delay was due to the fact that Germany was forbidden from having an air force by the Treaty of Versailles, and so the German government had to be ready to completely reject the Treaty before it could officially have an air force. In the early years of its existence the Luftwaffe would, like so many other air forces, dream of having a large fleet of four engined strategic bombers. They planned to use this fleet to directly attack their enemy’s civilian morale, and they also assumed that the enemy would do the same thing. Like others, German air theorists believed that it would be impossible to stop a strategic bombing attack after it had taken flight. One piece of the strategic bombing discussion what we have not touched on much so far is how each nation evaluated what would happen to their own civilians during a bombing exchange. Generally these evaluations looked at their own people as some how able to hold out longer than the civilians in enemy nations. In Germany this belief was rooted in the idea that a highly disciplined society, like that of Nazi Germany, with its rigorous government control and with its superior citizens, would be less effected by strategic bombing than other societies, like those lassez faire and weak western democracies. This tied directly into the racist foundations of Nazi ideology, which was centered on the idea that the German people, or the Aryan people more specifically, were simply morally superior to every other person. This would make them more prepared and able to stand up to the mental stress of being bombed, so I guess it gave them a +10 to their moral fortitude stat…or something like that. This theory would certainly be put to the test during the war, although the conclusion was generally that all civilians were better able to cope with bombing than many pre-war predictions. What would not be put to the test was a large fleet of German four engined bombers. They had two engine medium bombers, and honestly some of if not the best models in that category when the war started, but they would be unable to take the next step and build larger aircraft with a greater range and payload capacity. During episode 83 we discussed the change in direction that happened within the Luftwaffe after the death of Walther Wever, who had been a strong strategic bombing advocate, and the rise in power of Ernst Udet, and his staunch belief in the power of dive bombing. Many assumptions and guesses went into this calculation, and in Germany one of the major ones was the fact that Germany would always live or die by its ability to execute ground operations, either in offense or defense, and therefore they would justifiably place a large amount of emphasis on working with the Army. The Army, of course prioritized things that were more directly useful to their troops at the front. While changes in leadership and Germany’s geographic positioning were both important, another reason that Germany would have so many problems with the four engine bomber concept was simply that they had challenges building one. Due to the ban on military aircraft in the Versailles Treaty, Germany would enter into 1933 without a large aviation industry. Companies like Junkers and Heinkel did exist, and they were capable of producing aircraft as they had been building civilian aircraft after the end of the war, but it would take time for them to ramp up their ability to create large and complex military aircraft. The aviation industry would experience massive expansion between January 1933 and the end of 1938, growing from a tiny industry of just 4,000 workers to over 200,000, but no matter how many workers were thrown at the problem, they could not magically design something to build. Designing capable four engine bombers was a challenging endeavor, even for companies that had experience designing other aircraft. And when initial designs did not perform well the Luftwaffe would pivot in other directions. In some ways it was trying to maximize the number of engines and aircraft that would be built over a given period of time. Engines were, in general, time consuming and resource intensive, but if those engines were all placed into four engine bombers, that was 2 medium bombers worth of engines, or 4 single engine aircraft. Now, to be clear, engine manufacturing capacity is absolutely not directly transferrable on a moment to moment basis, but over a long period of time it can be. If you have a factory that can make x number of engines a month, that output can be altered and allocated a specific way given enough lead time. This would tie into another problem that the Luftwaffe would be plagued with during the years before the war, a focus on the number of front line aircraft that they could muster, instead of looking at the situation with a wider perspective. Another way in which this would manifest was a reluctance to divert production capacity into creating spare parts, instead focusing simply on making more planes. All of these issues were reasons why Germany did not have a four engine bomber at the start of the war, and they represent choices that can be defended or criticized based on how you evaluate the capabilities of strategic bombing.

When the war did start, Germany would still, regardless of any other problems, have several key advantages that would put it in a good place in the early stages of the conflict. First up, was their simple front line strength of reasonably modern and capable aircraft. Were spare parts maybe a problem? Sure, but they did not become a major issue during the early campaigns of the war which were generally quite short, which prevented any issues with spare parts of replacement aircraft from becoming a problem. Second, the Luftwaffe would have the advantage of experience. There had been many German air crews that had participated in the Spanish Civil War, and even those that did not participate benefitted from the feedback and lessons that had been learned in Spain. There would also be other great opportunities for experience to be gained when the war had started. The campaign in Poland, was a campaign in which the Luftwaffe largely controlled the action in the air, despite the best efforts of the Polish Air Force. This allowed the entirety of the Luftwaffe to gain crucial experience in real combat situations. The effect of all of this experience, when combined with the relatively light losses in the early campaigns of the war, meant that the Luftwaffe had a much higher number of combat hours on many of its pilots compared to the other opponents that it would face during the early years of the conflict. this was similar to the advantages that the Japanese would have due to their war in china, which also involved a large number of air operations with a relatively low attrition rate. A third strength was that the Germans would have very capable aircraft that would provide them with exactly the capabilities that they wanted. In 1939 the Stuka was a top quality dive bomber, the Me-109 was a very capable fighter, the medium bombers were excellent. All of these, and many other supporting aircraft were designs that hit at the right time for the Luftwaffe. They were designed and built late enough to be very capable or top of the line in 1939, but had been designed early enough that they could be fielded in reasonable numbers during the early campaigns of the war. Many of these advantages would evaporate over time, but that would all come later.

One interesting way to look at a military force, really at any point in history, is to view what other militaries believed about it. These beliefs are always some level of incorrect, but they can reveal interesting viewpoints on how specific actions were viewed, and what information decisions were being based on. For the rest of this episode we are going to look at what the British were able to gather about the strength, capabilities, and doctrine of the Luftwaffe before the Second World War. This was of course a very important topic for British planning purposes, and so a lot of effort was put into gathering and analyzing the available information. After Germany announced the creation of the Luftwaffe and the plans for Germany to enter a phase of rearmament, the focus of British intelligence was shifted very quickly to how capable the Germans were of expanding. Already in March 1934 there were reports that German aircraft production had increased by 50 percent in just a year, there would then be further reports in November 1934 that the number of workers in aircraft production and adjacent industries had doubled in just 6 months. The estimates for what this meant were all over the place, for example Air Chief Marshal Sir Edward Ellington would estimate that it would take the Germans until the end of 1939 to reach 1,000 planes. The French would share some intelligence that they had gathered that the Germans were actually aiming to achieve a total of 1,300 aircraft by October 1936. Now of course what the Germans planned to do and what they did do were two very different things, and as Germany would revise its targets ever upward in the last years of the 1930s British estimates of their strength would similarly increase. With British estimates of German capabilities all over the place, using them as an input into British planning was challenging. The data being received was such that for most of 1936 the British RAF Air Staff refused to endorse any specific predictions on German air strength beyond April 1937. In October 1936 they would finally release an estimate of Germany having 2,500 planes by April 1939. This was a number that seemed reasonable to others in the government, like the Foreign office that had dismissed some earlier predictions as too optimistic with the predicted German numbers being too low. That 2,500 would later be revised upward, which was in line with the fact that the Germans kept extending their production targets. Beyond just the raw numbers, which were important but not everything, there was also the question of what Germany planned to do with the aircraft, and this question was even more tricky. They did have some first hand information from the Germans themselves, for example in June 1937 the French would forward a copy of of the German Air Staff Analysis of some 1936 exercises. However, there were limitations to what this information could provide in terms of understanding how Germany would prosecute a war in the air. Quantitative metrics of German aircraft were very uncertain, with range and payload numbers unknown for the newest German bombers. This made it impossible to know what they were capable of. Was the Heinkel 111 and the Dornier 17 capable of reaching London from German air fields, and if it could would it have enough bombs to cause massive damage? The answer was almost always an unknown. These unknowns about German capabilities, along with a very real understanding of some of the challenges that Britain was having in extending its own capabilities, gave ample opportunity for more pessimistic views to come to the fore after 1937 and into 1939. It was a simple as taking the known British strength and comparing it to the greatest possible German strength. After the optimistic estimates of the early rearmament years, the estimates of both numbers and capabilities would swing decisively in the pessimistic direction right at the critical point where the actual threat of war was increasing. These estimates then had real and important impact on the government leaders making decisions and forming policy. But also, the run away fears of the possibilities of German air power gave a lot of support to those who wanted additional rearmament funds put into the Royal Air Force and air defenses. And it is hard to say that those resources were not critical to British actions after 1939.