2. Archives
3. IHR
4. JHR Volume 7

From the Spanish Civil War to the Fall of France: Luftwaffe Lessons Learned and Applied

PETER H. OPPENHEIMER

Operation Magic Fire (28 July 1936 — 29 March 1939)

Hermann Göring proclaimed the existence of the reconstructed German Luftwaffe on 10 March 1935.[1] Within eighteen months, the new Luftwaffe embarked upon Operation Magic Fire, a program to assist the Nationalists in the Spanish Civil War. The war, which broke out in the summer of 1936, provided Hitler with an excellent opportunity to distract European attention from his machinations elsewhere on the Continent while at the same time enabling the fledgling Luftwaffe to field test its air warfare doctrine and equipment in military action.[2] The Luftwaffe learned much from the Spanish War in the way of strategy, tactics, logistics, and operations. These lessons were reinforced by the Polish Campaign in September 1939 and applied in Scandinavia, the Low Countries and France in 1940.

Condor Legion was the name given to the German military units dispatched in November 1936 to fight in Spain. The task of this paper is to address issues surrounding the Condor Legion in Spain. Specifically, what lessons did the Luftwaffe learn from the Spanish War? What was the role of the Condor Legion in that war? Was the Luftwaffe helped or hampered by the experience of the Spanish Civil War? Did the Spanish War play a decisive role in influencing the Luftwaffe operational doctrine that contributed to Germany’s defeat in World War II? By answering these questions, I hope to show that the Spanish War provided ambiguous benefits to the nascent Luftwaffe. Although the Condor Legion involvement in Spain proved an invaluable training and testing opportunity, the lessons it taught were occasionally interpreted erroneously. On the whole, however, the Condor Legion experience in Spain established a wellspring of variegated experience from which the Luftwaffe was to draw heavily at the beginning of the Second World War.

Small Beginnings

On 18 July 1936, Adolf Hitler approved the Spanish Nationalist request for military assistance in the civil war that had begun one day earlier.[3] Within ten days, twenty Junker Ju52s had been dispatched to Spain, flown by Lufthansa (Germany’s commercial airline) pilots and Luftwaffe volunteers. Shortly thereafter, six Heinkel He51 biplane fighters were shipped to Spain, along with twenty 20mm flak guns.[4] Although many historians have claimed that Germany entered the Spanish conflict without reservation, this is untrue. Hitler supported Franco over the objections of every ministry in his government.[5] However, the initial German assistance was restricted in both men and materiel. Indeed, only 85 Luftwaffe volunteers were sent originally to serve in Spain under the command of Major General Hugo Sperre, and the designated mission explicitly excluded direct military participation in combat operations.[6] The Freiwillige (volunteers) released from the Luftwaffe were under orders only to train Spanish men to fly the German planes. In less than a week, however, one of the Spanish trainees killed himself and destroyed a plane, while two other Spaniards crashed on their first mission.[7] Because of these mishaps, the German pilots sought and received permission to fly combat missions.[8]

The international reaction to German intervention in Spain was both immediate and hostile. Great Britain lodged a formal protest against the German volunteers and began to support the Spanish Republicans.[9] The Soviet Union subscribed to a French non-intervention plan in principle, but then demanded that Germany immediately cease aid, and began to aid the Republicans themselves.[10] Göring, having succumbed to Hitler’s desire to intervene in Spain; demanded that the Luftwaffe expand yet faster.[11]

Hitler’s true reasons for intervening in Spain had little to do with Franco’s need of assistance or the simple desire to test and develop military equipment; rather they were strategic.[12] A Nationalist-controlled Spain, as Antony Beevor points out, “would present a threat to France’s rear as well as the British route to the Suez Canal."[13] There was also the tempting possibility of U-boat bases on Spain’s Atlantic coast (Spanish ports were actually used occasionally by the Germans during World War II). Hitler also viewed the war as a way to forge the Axis with Italy while distracting Mussolini’s attention from Austria and the Balkans. The idea of the war as a testing ground for German equipment was secondary at best. Yet as the equipment initially provided to the Legion demonstrated itself deficient, Berlin responded by supplying new, untested aircraft.[14] Spain became a testing ground for the Luftwaffe by chance, not design.

In Spain, the Condor Legion was divided into six parts: a command staff (S/88), one bomber wing with three squadrons of Ju52s (K/88); one fighter wing with three squadrons of He51s (J/88), a reconnaissance squadron of twelve He70s and four heavy flak batteries of 88mm guns (A/88), two 20mm light flak batteries (F/88), and a communications detachment (Ln/88).[15]

Pre-Spanish Civil War Luftwaffe Doctrine

The airwar theoreticians most influential in the West in the 1920s and the 1930s were Douhet in Italy, Mitchell in the U.S.A, and Trenchard in England. Basically, these men postulated that airplanes could be the decisive factor in the next major war. The air provided a third dimension in which the static trench warfare in World War I could be avoided.[16] The essence of their idea lay in “strategic” bombing. Countries would possess large numbers of long-range bombers capable of destroying the enemy’s cities and industrial base. Large-scale destruction would quickly lead to the collapse of the enemy’s economy, the demoralization of his people and a quick end to the war. Inherent in this theory was the belief that “the bomber always gets through". In other words, fast, long-range, heavily armed bombers were invincible and unstoppable. Some of Douhet’s extreme adherents even claimed that air warfare made the army and navy superfluous.[17]

Germany’s airwar visionary during this period was Walther Wever, head of the Luftwaffe until his death in 1936. Wever studied Douhet’s teachings but believed that a broadly based air strategy was superior to “strategic” bombing, [18] and he argued that the air force should complement the army and navy.[19] his death left the Luftwaffe with less capable men in charge. Nonetheless, the doctrine governing Luftwaffe air power was formulated by Wever before he died. Fundamentally, the three military services were to co-operate in order to achieve the foremost goal of any war, that of destroying the enemy armed forces. “It is the task of the air force in leading the war in the air within the wider framework of the whole war to serve this goal.” [20] More specifically, Luftwaffendienstvorschrift 16: Luftkriegsführung (Luftwaffe Service Regulation l6: Conduct of the Air War) laid down three points: (l) subjugation of the enemy air force in order to achieve and maintain air superiority; (2) support of the army and navy; (3) attack against the enemy industry.[21]

These three points implied that the Luftwaffe should destroy the enemy air force over its own territory, if possible when it was still on the ground. For good measure aircraft factories ground installations, and air fields were also to be bombed. Secondly, support of the army was critical. Bombers were to clear the way for tanks and infantry by destroying depots, harassing enemy troops, and disrupting communications. Already, Luftwaffendienstvorschrift 16 hinted at the future subordination of the Luftwaffe to the Army. Once these two primary tasks had been accomplished, airplanes were to bomb production centers, food supplies, railroads, ports, traffic centers, military recruiting centers, and Government administrative centers.[22]

Luftwaffe doctrine presumed that the defense of the homeland would be the responsibility of the flak batteries. This was no nearsighted daydreaming. Prewar anti-aircraft units were highly trained and extremely effective, perhaps the best in Europe.[23]

Therefore, the prescription for aircraft production prior to the Spanish War, based on the assumption that fighters were not required for homeland defense, was three bombers to every fighter.[24] When, as a result of the Spanish War, Colonel Ernst Udet, head of the Luftwaffe’s technical department and Office of Air Armament, decided to change the Luftwaffe’s force structure from a three bomber to one fighter ratio to two bomber to one fighter ratio, it was for purely offensive reasons.[25] As far as German naval air theory was concerned, an independent naval air arm was to be created, consisting of floatplanes, flying boats, and naval fighter planes.[26] This arm would co-operate with the Navy, both offensively and defensively. Inexplicably, no aircraft carriers were completed by the Germans, although two were planned and construction on the Graf Zeppelin was begun. This strategic error indicated the myopia of the Navy general staff, which did not expect a general war until 1943-4, the landlocked nature of German air power thinking, and the fierce interservice rivalry within the Wehrmacht (armed services).The psychological component of air warfare was not neglected by Luftwaffe theorists. As early as l933, the Luftwaffe began to plan for war. Most strategists argued that the next war would be total, entailing the complete mobilization of the civilian population and the engagement of all the country’s resources. Under these conditions, many people argued that the unity created by the Nazis would better enable Germany to withstand an all-out struggle. Terror bombing of cities by the Luftwaffe would result in the collapse of the enemy’s morale and his consequent surrender. The same people assumed that a totalitarian society like National Socialist Germany would more easily endure bombing attacks than the fractured societies of France and Britain. This attitude oriented Luftwaffe thinking throughout the 1930's.[27]

In spite of the explicit air power doctrine laid out by Wever in Luftwaffendienstvorschrift 16, the Luftwaffe had little opportunity to field test its aircraft and theory in the years between its inception in 1933 and the beginning of the Spanish War in 1936. Thus, the Luftwaffe’s overriding theory was “to employ maximum forces at the decisive point of the battle.” [28] The course of the battle would necessarily dictate changes in both strategy and tactics, but this was something the Luftwaffe was prepared to do.

Tactical Lessons from the Spanish Civil War

It was in the realm of tactics, among other areas, that the German military excelled, and it was in the realm of air tactics that the Luftwaffe benefited the most from the Spanish War. The key individual in this area was Werner Mölders. During the Spanish War, Mölders grasped the change in airwar brought about by the monoplane’s increased speed and maneuverability, and he developed the Rotte and Schwarm fighter formation (called the finger-four by the British and Americans), which in one form or another is still in use today. Instead of the World War I fighter group locked in tight wing-to-wing “V” formation, the Rotte consisted of two planes, one tailing the other to protect the lead plane’s rear.[29] A Schwarm consisted of two Rottes, and the Schwarm configuration mimicked that of the Rotte.[30] When several of these units of four joined to make a Staffel (squadron), the units were staggered at different altitudes as a means of mutual search and protection.[31] This formation possessed several advantages. The increased distances between the planes allowed for greater maneuverability and higher plane speeds. This in turn gave pilots greater flexibility when confronting opponents and enabled them to use their firepower more effectively against those opponents.

The Spanish War also indicated how difficult it was for conventional bombers to hit targets both at day and night.[32] This difficulty led the Luftwaffe command to favor the more accurate dive bomber over conventional bombers. The Germans' failure to develop an accurate bombsight further reinforced support for the dive bomber. Night attacks pointed to the difficulty of not hitting targets, but finding them as well. As a consequence, the Luftwaffe placed great emphasis on the development of navigational aids essential for bad weather and night operation. The ultimate result was the Knickebein system, first used in the Battle of Britain. Knickebein was a blind-bombing system which utilized radio direction to assist aerial navigation.

Low-level attacks were another result of conventional bombing’s inherent inaccuracy. A First World War development refined during the Spanish conflict, low-level attacks enabled pilots to judge their bombing runs more accurately and to conduct strafing attacks which demoralized enemy troops, disrupted enemy communications, pinpointed enemy artillery. The one great disadvantage of ground level attacks was that they exposed aircraft to ground fire. No less significantly, ground level attacks increased the chance of crashes since there was very little time for a pilot to deal with an engine stall, unexpected terrain features, or any similar disastrous surprise.

The Spanish conflict revealed the importance of communications as well. The Luftwaffe realized that the signal corps needed to be equipped with radios to maintain close contact between air and ground forces. Furthermore, the new Rotte formation dictated an increase in the distance between planes. Although hand signals had sufficed in the past, German pilots perceived that air-to-air radio communications had become critical to the success of the new tactics.

Yet in order to understand the influence of the Spanish War on the Luftwaffe, several other areas of air warfare tactics must be addressed in greater detail. They are the development of close ground support of infantry by the Condor Legion, the evolution of fighter tactics, bombing, and reconnaissance.

Close Ground Support

Low-level attacks and close support of the infantry were tactics developed by Wolfram von Richthofen during the Spanish War.[33] During the first battle of Madrid in 1936, German air tactics proved inadequate, primarily because they were experimental.[34] The Legion acted as airborne artillery, bombing and strafing Republican strongpoints and then quickly fleeing.[35] This proved ineffective. However, by functioning as airborne artillery, the Germans learned the importance of close coordination with the ground forces so as to avoid attacking friendly troops. The Legion developed extensive communications, linking planes and ground forces, to avoid just this danger. A Legion officer was assigned to the assault troops and linked by radio to the Legion Command Post. An advantageous relationship resulted. Because the Versailles Treaty had forbidden the Germans from having an air force, almost “all future Luftwaffe officers, in the early period, had extensive training and experience in the infantry, artillery, or cavalry, and held a great knowledge and appreciation for the problems of ground commanders.” [36] In addition, Nationalist troops often attached white panels to their backs so they could be easily identified from the air. When necessary, they used flares and smoke pots as well.[37]

The equipment initially supplied to the Condor Legion also impelled close ground support. Condor Legion pilots soon discovered that their He51 biplanes were outclassed by the Russian Polikarpov I-16 monoplanes and took pains to avoid direct combat confrontation.[38] Moreover, the Nationalists were deficient in artillery.[39] As a result, the He51 was assigned the role of low-flying artillery in support of Nationalist infantry.

Ground support tactics did not develop immediately, nor did they ever attain the simplicity of textbook formulation. Rather, experience illustrated the necessity of a flexible response to local conditions. The general pattern was for German 88mm guns to bombard enemy strongpoints, followed by bomber and fighter attacks. The infantry advanced directly behind the low-flying planes.[40] There were many variations of this basic pattern. For instance, during the Battle of Brunete in July 1937, General Sperrle divided his squadron into four flights of two planes each. Successive flights swept in abreast of the enemy flak batteries, opening fire with their machine guns while still a good distance away. Over the batteries, they salvoed their bombs and pulled up as quickly as possible to avoid their own bomb blasts.[41] It was essential to neutralize the enemy flak batteries because the cumbersome Ju52 bombers which followed the fighters were easy targets.[42] Low altitude attacks also helped ensure that the Ju52s would not bomb friendly infantry. By dispatching successive relays of air attacks, the Legion wore down Republican defenses and shattered the morale of Republican forces.[43]

In the North, tactics perfected during the attacks against the Basques were put into practice. Heavy artillery and aerial bombardments destroyed the enemy defenses while He 111 bombers escorted by Bf109s penetrated deep into Republican territory, bombing important enemy targets.[44] During the Nationalist attack on Madrid in late 1936, the Republican chief of staff complained of the devastating air strikes launched against him. “The machine gun fire kept (his] men pinned to the ground to the point where they could not man their guns, and attacks in the rear caused great confusion.” [45]

Mass formation of bombers was yet another revision of tactics prompted by the well-fortified enemy strong points in the Basque North. Because an attack by only one or two aircraft simply drove the enemy into his dugouts, safe to reappear after the planes had passed overhead, the Condor Legion pilots approached the enemy from the rear, dropping their bombs all at once. The combined explosive power of the bombs was often sufficient to destroy the fortified dugouts. This innovation the pilots dubbed, “the little man’s bomb-carpet.” [46] Thus carpet-bombing was born.[47] The talent for responding flexibly to local circumstances characterized the Legion’s development of close ground support tactics, and it cannot be emphasized strongly enough that Colonel von Richthoften deserves the primary credit for the development of these tactics.

Evolution of Fighter Tactics

Fighter tactics in World War I were crude in form, constrained by the slow and unwieldy triplanes then available and limited by the lack of knowledge about aerial combat in general. As the war progressed, pilots gained experience, armaments were developed, and airplane designs advanced. But relative to World War II, airplanes and tactics in World War I were primitive. Usually, each side massed its planes to maximize total firepower in twisting dogfights. With the advent of fast monoplanes, however, tactics changed to accommodate and exploit the improved capabilities of the single-winged aircraft. Raymond Proctor explains that monoplanes

emphasized the elements of maneuver to firepower in formations. With speed and maneuver came closure, and with it the need to sight the enemy first and to protect the vulnerable tail areas. 80 % of all aerial kills are attained with the aircraft shot down never knowing the enemy is there and the attack usually comes fiom dead to the rear (or the 6 o'clock position). In the traditional formation the pilot of the new high-speed aircraft had far too much of his attention distracted by guarding against crashing into his wingman and was thereby vulnerable to enemy attack.[48]

As a consequence of the increased vulnerability of the monoplane fighter, particularly when utilizing biplane tactics, Werner Mölders devised the Rotte and Schwarm configurations described above. Yet until the Condor Legion received advanced equipment, fighter tactics in Spain differed very little from those of World War I, indeed, the slowness of the He5ls in comparison to the Russian monoplanes was not an overwhelming handicap in most instances. Only when the pilot of an He51 broke off combat with an enemy monoplane fighter did the relative slowness of his biplane become potentially fatal.[49]

On 29 October 1936 the decision was made in Germany to send modern equipment to Spain, including the Bf 109 monoplane fighter.[50] The Bf109 enabled the Condor Legion to drive the Soviet I-15s and I-16s from the skies, conclusively establishing German air superiority in Spain.[51] The offensive and defensive advantages of Mölder’s finger-four fighter formation soon proved extraordinary successful. Each Rotte, when necessary, could act as an independent entity in search, defense, and attack. Cooperation between two Rottes — as a Schwarm — increased total firepower and visual protection. When one Rotte was attacked, the other Rotte of the Schwarm, some 600 feet from its companion, was able to turn in on the enemy, bringing all its guns to bear. When attacking the leader assumed the role of a gunship while his wingman flew in a “cone” pattern to his rear, effectively protecting the leader plane’s 6 o'clock position.[52] The increased distance between the planes of a Rotte allowed the pilots to focus their attention on scanning the sky rather than on striving to maintain close formation.[53]

At times, He51 s were used as bait in Spain. The biplanes flew several thousand feet below a squadron of Bf109s, which waited until Russian I-16s attacked the He5ls. The I-l6s were then attacked by the Bf109s. During an attack, the Bf109 sought to dive from a superior altitude and pass the enemy aircraft from below, coming up behind the intended victim in his blind spot. If the pilot missed, he could use his diving velocity to escape with speed, or climb again and attempt another pass.[54] Another particularly innovative fighter tactic involved a good measure of foresight and a careful calculation of “aloft” time. Several German planes would circle in the sky near the Soviet airfields. Soon, Soviet fighters scrambled to challenge the Condor Legion pilots, who intentionally stayed out of range until the Soviet interceptors ran low on fuel. Then, another Legion flight, carefully timed to arrive over the enemy airbase as the Soviet planes refueled, bombed and strafed the grounded aircraft.[55] Eventually, the Soviets responded with appropriate defensive measures, but not before they had lost many planes.

Bombing

The effectiveness of bombing in the Spanish Civil War remained uncertain and for that reason provided the Condor Legion with lessons of dubious value. Spain was an unusual war because by mid-1937 the Condor Legion had achieved an infrequently contested dominance of the air, an advantage rarely enjoyed by an air force.

Throughout the war, German bomber pilots usually flew sorties without a fighter escort deep into enemy territory. The Republicans possessed little artillery, and what they had was generally ineffective. The freedom to bomb the enemy, unhindered by opposition, either in the air or from the ground, led the Germans to believe that a fast, heavily armed bomber was the decisive weapon in a military conflict involving aerial attacks. In many ways, the German experience seemed to support Douhet’s concept of “strategic” bombing in that it illustrated the ability of unescorted bombers to penetrate deep into enemy territory and inflict great destruction in mass bombing attacks. Yet the Germans did enlarge upon Douhet’s theory. Rather, they attempted to combine the elements of both fighters and bombers into one plane on the assumption that the resulting aircraft would be better than either its precursors.[56] Close ground support tactics also uncovered the desirability of combining both bombing and strafing capabilities into one airplane. In this way, the Germany military expenditures for the Luftwaffe could be economized, thus burdening the economy to a lesser degree. However, this was one of the many erroneous lessons drawn from the Spanish Civil War experience. The German experience with daylight bombing, night bombing, dive bombing, and naval bombing must be more fully examined to explain the development of Legion bombing tactics in Spain.

From the beginning of the war, the Legion used classical bombing tactics, adapting their methods whenever necessary to meet local contingencies. Basically, classical tactics entail close ground support of friendly infantry, interdiction of enemy supplies, and bombing attacks against enemy strongholds, troop formations, transportation, and communications. Occasionally, fighter escorts were assigned to the bombers, but this became less necessary as the Legion attained air supremacy. During the attack on Bilbao in the summer of 1937:

German bombers and other air groups dropped heavy bombs in daily attacks, from morning till night, on hill positions, tunnels, command posts, artillery positions, and troop concentrations. Also, they continually bombed the passes north of Miravelles to interrupt all traffic. All air groups were ordered not to bomb, under any circumstances, villages or populated areas.[57]

The latter order, forbidding the bombing of populated areas, was soon violated. Madrid was the first European capital city in history to suffer aerial bombardment. The Germans bombed most of the residential districts of the city in a vain attempt to break the morale of the civilian population. According to Antony Beevor, this methodical experiment in psychological warfare “served only to make the populace more defiant.” [58] The Stuka was to alter that.[59] But until dive bombing received greater emphasis, the Germans concentrated on low altitude bombing runs to compensate for the difficulty Legion bomber crews encountered in accurately placing their bombs on target. Even if the Germans had possessed an accurate bombsight, it is unlikely that it would have made much difference. Bomber crews required exhaustive training to learn precision bombing, and the Condor Legion airmen could afford neither the time nor the effort for such training. Yet, because of the minimal opposition encountered by Legion aircraft, daylight bombing was very effective. The Heinkel He111, a fast, heavily-armored medium bomber, arrived in Spain in 1938 and admirably fulfilled the role prescribed by the Spanish situation.[60]

Because of the He111’s successful performance in Spain, the Luftwaffe deduced that the medium bomber could be improved simply by designing a larger version. When the Ju52 demonstrated itself inadequate as a bomber, [61] the Luftwaffe Technical Office staff requested a plane that would both correct the deficiencies of the Ju52 and extend the capabilities of the He111. More specifically, they ordered a medium bomber that:

1. had a flight time of five rather than three hours
2. had a bomb capacity of at least two tons
3. had a fully glazed nose for better visibility
4. had heavier armaments (i.e., more defensive machine guns)
5. had improved radios
6. had a stronger landing gear and fuselage
7. had larger engines to cope with the increased weight and to provide improved flight performance.

The plane ultimately developed was the Ju88 the so-called 'super' medium bomber.[62] Initially, this plane proved a failure, and saw little combat action in Spain.[63] Nevertheless, the Luftwaffe had wed itself to the medium bomber concept embodied by the He111, a concept that though spectacularly successful in Spain, eventually contributed to the Luftwaffe defeat several years later.

Night bombing was practiced infrequently in Spain due to the virtually insurmountable difficulties night operations posed. Yet during the early stages of the conflict, when the Republicans were still capable of mustering a significant fighter defense, General Sperre decided to engage the enemy in hours of darkness only.[64] Over Madrid the Legion bomber flights could gauge distances and destinations accurately because the truck traffic, upon which the city depended, was illuminated by its own headlights. Perceptively, Legion bombers struck when truck progress was slowed by bottlenecks at bridges and by the narrow roads of small towns. Weather permitting, the pilots flew sorties every night. However, the results left no doubt that it was difficult to hit small bridges with poor bomb sights at night. Luftwaffe Chief of Staff Albert Kesselring, Walther Wever’s successor, drew the obvious conclusion: night bombing was effective only when the crews possessed a high degree of discipline and technical competence.[65]

Night bombing was also extraordinarily demanding in terms of training, navigation, and mission execution. As a result, bomber research and development were directed toward two distinct goals. Men like Colonel Ernest Udet were convinced that every bomber should have a dive bombing capability. Others pushed Luftwaffe scientists to experiment with radio directional systems to aid navigation and answer the problem of bombing at night and in poor weather conditions. To fulfill the latter goal, the Knickebein system was developed and then tested for the first time in the Battle of Britain. The former goal, that of dive bombing, received a great deal more attention during the Spanish Civil War, where it was elaborated and refined.

The Spanish Civil War suggested to the German Air Staff that dive bombing was the single most accurate bombing method. As elucidated above, the special circumstances that existed in Spain enabled the Condor Legion to operate virtually uncontested in the skies over the Iberian Peninsula. Moreover, the equipment with which the Legion was provided proved unsuitable for “strategic” bombing missions. At first the Germans attempted to use the Ju52 as a bomber, but it was slow and lumbering, and thus an extremely vulnerable target for Republican anti-aircraft batteries. Not until later, in 1937, did the Legion receive aircraft, such as the He111, which was more adequate for “strategic” bombing missions. In any event the unqualified success of close ground support operation underlined the need for an aircraft that could drop bombs with pinpoint accuracy — something conventional bombers proved unable to do — so as not to scatter bombs on friendly forces. The plane that fulfilled these requirements was the Junker Ju87 dive bomber, first used during the Battle of Teruel in 1938.[66] The plane had peculiarly angled wings which gave it the appearance of an ugly vulture, and Luftwaffe officers in Spain claimed that the Stuka could drop its bomb load within five meters of a target.[67]

Wolfram von Richthofen discovered the Ju87 not only to be an accurate bomber but a psychologically demoralizing weapon as well. A technician suggested attaching sirens to the landing gear, a development which gave the Stuka its trademark whistling sound as it hurtled down on its target. Perhaps more so than the bombs themselves, the Stukas' sirens scared Republican forces, sometimes creating such a panic that the troops abandoned their weapons and fled. As the Stuka proved the value of dive bombing, the emphasis in production in Germany shifted toward the Ju87, confirming the belief among the military staff that the bomber was a tactical offensive weapon.[68] Precision bombing replaced “strategic” bombing for the Luftwaffe in Spain, and this partially explains why the Air Staff neglected the development of a heavy, four engine conventional bomber so sorely needed in later years.

For the Germans, the story of naval bombing in the Spanish Civil War was characterized by minimal results. German naval air theory in the years 1935-1939 supported the idea of an independent naval air arm with floatplanes, flying boats, and naval fighter planes cooperating directly with the Navy. However, the theory was rarely applied. Initially, land-based attacks by planes also proved ineffective. In late October 1936 Franco urged the Condor Legion to bomb Republican naval and supply ports. It did so with disappointing results.[69] Over a year later in the Mediterranean, another attempt was made at maritime bombing to interdict Soviet shipping. This time the Condor Legion enjoyed greater success, its seaplanes raiding shipping at sea by day and in harbor by night. On Franco’s orders, the maritime bombing attacks escalated into a full-scale offensive. As Willard C. Frank notes, “Raids became continuous, severely reduced the supplies needed to maintain the [Republican] civilian population, and did serve to undercut morale.” [70] By the end of the war in 1939. Italian and German aircraft had sunk 115 Republican and 51 foreign merchant ships, a total equal to nearly 75 percent of all enemy ships destroyed by those two countries during the entire war. Another 225 bombing sorties during this period damaged or delayed many Republican cargoes. choking off a source of the besieged population’s food, clothing, fuel and medical supplies and producing increased misery and despair.

Dive bombers were intended as the basic instrument of enemy shipping’s destruction. However, the only plane available at that time, the Ju87, originally had only a one-hundred mile operational radius, a factor which limited flight time. Legion pilots did ascertain that torpedo attacks and dive bombing were very promising.[71] But the Luftwaffe developed neither a long-range dive bomber nor a torpedo bomber. The He59 and He115 floatplanes were intended to be torpedo bombers, but they never carried out an operation. The Germans were aware of their limitations, but because of their indifferent attitude, they failed to exploit the equipment at hand. The Air Staff believed that the larger German warships received adequate service from their Arado and Heinkel floatplanes. This helps to account for the nearsighted decision not to complete the German aircraft carrier, the Graf Zeppelin.[72] In any case, the High Command in 1937-39 believed that war with Great Britain could be avoided, and men like Ernst Udet did not believe that Germany would wage war against a maritime power like Great Britain.[73] As an result of the maritime air war during the Spanish War, the Germans falsely deduced that ships underway did not need to fear aerial attack. Consequently, naval officers procrastinated dangerously on improvements for shipboard anti-aircraft defenses.[74] Overall, the Luftwaffe concluded that a separate naval air arm was unnecessary, and by 1940, it had begun to be reabsorbed into air force land-based squadrons.

Reconnaissance was ultimately the most successful element of German naval air policy in Spain. Initially, reconnaissance, both over land and sea, was viewed negatively because of the scanty results obtained.[75] It was believed more important to wear the Republicans down through continual bombing. But this anti-reconnaissance attitude changed as the reports obtained through aerial observation demonstrated their value. Observation planes located the enemy, thereby conserving resources by eliminating the wasteful practice of simply sending bombers on haphazardly planned and implemented missions. Given the nature of the conflict, with the great mobility of ground forces, it was important to know the enemy’s exact location at any given time. At the Battle of Brunete, Nationalist observation planes were sent aloft. Within thirty minutes of sighting the enemy concentrations. Legion bombers appeared to strike and strafe the Republican troops.[76]

The Republican Air Force always made a great effort to shoot down the Nationalist reconnaissance craft, and these observation planes were forced to engage in evasive tactics to preserve themselves. As a general rule, observation planes were less heavily armored and armed than combat aircraft. Speed was most important. When attacked, the reconnaissance planes made for a cloudbank to hide. If none was available, the planes went into a dive to gain sufficient speed to escape their pursuer, or at least limit them to one attack. Another tactic practiced by the reconnaissance planes was to begin firing their machine guns long before they were in range of enemy fighters, occasionally causing the enemy to break off his attack too early. “Considering its technical disadvantage, the Legion lost few reconnaissance planes.” [77]

Logistics & Operations

Mobility was the key logistical lesson taught the Luftwaffe by the Spanish War. The need for mobility had been demonstrated by the Italian military experience in Ethiopia in 1935-36. Mobility was frequently the key to the success of the Italian forces against the well-armed and well-trained Ethiopian Army. Yet, for the Germans in Spain, mobility meant more than just rapid deployment of men and equipment. It found its essence in ground-staff mobility.[78] The use of air transport and railroads to move entire unit installations quickly lay the groundwork for the Blitzkrieg as later practiced in Poland. The Wohnzug (railroad caravan) was the quintessential example of mobility in practice. The Wohnzug consisted of approximately eleven railway cars, two of which were locomotives attached at either end of the train, eliminating the need for turn-arounds. One-third of the cars contained sleeping compartments for officers and enlisted men. At a moment’s notice, the Wohnzug could be underway with all the squadron’s equipment and support personnel. The flight crews flew their planes to the next designated base of operations to await the rest of the railroad-transported squadron. By 1939, each Condor Legion squadron was also assigned two Ju52s to be used both as transports and as radio direction-finding stations.[79] The Ju52s proved reliable workhorses, perfectly suited to the task which was set for them.

In operations, the Condor Legion learned how important ground support personnel were, particularly in the inhospitable environment of Spain. The men who fueled the motors, tinkered with the engines, and replaced broken or damaged parts played an indispensable role in the Condor Legion. At first, the Legion underestimated the number of personnel required to care for the aircraft properly as well as the number of reserves needed to replace over-tired, injured, or killed front-line pilots. The exertions demanded of the men, including long, irregular hours frequently under harsh, stressful conditions indicated that the workload had to be more evenly distributed among more men. The Legion had not realized at the beginning of the conflict that air warfare is continual. But it soon became clear that the squadrons had to carry out many tasks without resting, a feat which quickly exhausted supplies and men.[80]

The lesson in operations typified the manner in which the Luftwaffe took advantage of the war not only to evaluate its practices but also its organization. During the course of the war, the flight elements of the battle squadrons and their ground personnel were reorganized, forming the basis for what later became standard operational configurations.[81] A special combat reporting team was set up in Berlin and dispatched to Spain with orders to send back periodically for analysis and evaluation.[82] In addition, the Lehr Division (Technical Development Flying Unit) was formed at Greifswald in 1937.[83] Its purpose was to discover the lessons of the Spanish conflict and distill the experience derived from air competitions and factory research. Essentially, the Lehr Division functioned as a post-graduate flight school and advance operational training center devoted to absorbing and teaching new tactical air lessons, many of which came from Spain. Not surprisingly, much of what was learned was subsequently adopted as standard procedure to be used by the Luftwaffe throughout World War II.

Air Theory Applied in Spain

The theory of air doctrine described by Giulio Douhet in his book, The Command of the Air (1921), postulated a concept of “strategic” bombing which simply did not apply to the conflict raging on the Iberian Peninsula between 1936 and 1939. Douhet’s theory was predicated on the premise that the static trench warfare epitomized by World War I set the pattern for all future ground wars and that “strategic” bombing provided the only means to avoid bloody wars of attrition. In Spain, the contest between the Nationalists and the Republicans was of a fluid and mobile nature, covering many different types of terrains and climates, constrained by delicate political circumstances. and limited by the available equipment. Douhet suggested the way to win a war was to destroy the enemy’s cities and industrial base. In Spain, however, there was very little large-scale, heavy industry. It was perhaps to be expected that Spain was not, and, indeed, could not be, the war to verify Douhet’s theory. Except for the unusual circumstances that enabled Condor Legion bombers to attack the Republicans virtually unmolested, there was little proof that a well-organized fighter defense would be unable to check “strategic” bombers.

The development of close ground support tactics arose naturally, then, from the peculiar situation in Spain, as did the emphasis placed on dive and medium bombers. Many other factors contributed to the course of these developments, but they were of a more secondary nature.

On 1 May 1937 Richthofen wrote a letter to the Luftwaffe High Command stating “Spanish [Nationalist] artillery is always late in arriving; it fires too slowly and too poorly to keep the enemy pinned down. The load of the battle rests with the flyers; first by inflicting casualties, second, by holding him down, making him run, destroying his spirit to fight, and hindering his resupply and reinforcement.” [84] Here was a cogent summary of Condor Legion air doctrine as practiced in Spain. The air force, claimed Richthofen, bore the primary responsibility for executing the attack. Intrinsic to his belief was the desirability, indeed necessity. of close coordination between the army and the air force. The goal of the Legion flight elements was threefold: (1) seek out the enemy air force in order to remove the threat to the army, (2) attack the enemy army, harass his troops, transport and communications, and (3) protect ground troops and infantry from enemy air attack.[85] After air superiority had been established, the air force could then switch from air-to-air to air-to-ground attacks.

The Luftwaffe High Command was unaware of the efficacy and applicability of close ground support tactics at the outset of the Spanish War. It was still enthralled by the concept of “strategic” bombing. Von Richthofen slowly but surely weaned the High Command from its strategic airpower beliefs and persuaded it that close support tactics had great potential.

Some authors argue that Germany came to have an air force based on tactical air power rather than general air power because of the influence and predominance of the German Army.[86] For such authors, it was natural that the fledgling Luftwaffe be subordinated to the long-established army. But in truth there was such general opposition to anything but “strategic” bombing that it was only Richthofen’s perseverance and determination that led to the acceptance of tactical air power.[87] The first close support operations in Spain took place in March 1937 when He51 fighter bombers made a low-level attack on the Republican front at Bilbao with great success.[88] For the Germans. tactical air power as an operational doctrine and a strategy dates from this incident, and in retrospect, changed the course of the next war and all future wars.

Other forms of bombing were not precluded as a strategy merely because Richthofen developed close ground support tactics. But that bombing was included in strategic planning does not mean the same thing as “strategic” bombing. As indicated above, high altitude “strategic” bombing was practiced infrequently by the Condor Legion during the Spanish War because of the various political, economic, and structural circumstances. Yet the Spanish Civil War was not spectacularly successful with interdictory bombing. Its pilots discovered that conventional, high-level precision bombing was difficult in the best of conditions and virtually impossible against heavily defended or pinpoint targets.[89]

The lack of an accurate bombsight contributed to this inadequacy. Therefore, the move towards dive bombing was natural. The putative effects of “strategic” bombing — destruction of industrial bases, devastation of morale among the working population, and psychological demoralization of the civilian populace- as the 1938 Luftwaffe Yearbook indicates simply had not occurred.[90] In this light, it became apparent that “strategic” bombing was not only difficult to carry out, but was ineffective as well. Dive bombing, with its promise of great precision, seemed to portray the future. Another reason for the demise of “strategic” bombing in Spain was inextricably linked to the death of Walther Wever. Wever’s belief on the heavy, four-engined “Ural” bomber died with him, and there was no one else in the High Command willing to put through a costly and hypothetical program without sure knowledge of its ultimate result.

Personalities also exerted influence on the direction of Luftwaffe air theory. For example, Ernst Udet maintained a hold upon Colonel General Hans Jeschonnek, Luftwaffe Chief of Staff from February 1939 onwards.[91] Udet’s preoccupation with speed propelled German Air Staff policy in the direction of a fast light bomber, rather than Wever’s “Ural” bomber.[92] As a consequence, Germany never manufactured the equivalent of the United States Air Forces’s Boeing B17, a blunder that contributed to the Luftwaffe’s failure to bomb England into submission during the course of 1940.

The intermingling of hard-headed doctrine and vain desire, economic constraints, and overrated successes led to an erroneous application of fighter forces in the defense of the Reich in 1943-44. Spain engendered a belief in the quasi-omnipotence of the flak batteries. Germany had produced an extraordinarily effective anti-aircraft gun in the 88mm, a weapon used with repeated success in the three years of the Spanish War. The 88mm gun was used in Spain not only to protect against enemy aircraft but also to attack ships, tanks. troops, or any other ground targets. The confidence in the flak batteries was reinforced by the elite nature of the men that operated the guns. Pre-war anti-aircraft units constituted an independent. highly-trained body of men.[93] Total reliance was placed upon these men to protect against intruding enemy aircraft. As a result, the Luftwaffe neglected to develop early warning radar, as the British did, or fighter control, by the outbreak of war. This weakness was partially compensated by the excellent aircraft reporting system linking flak and fighter units (cf. Richthofen and close support tactics), but it was hardly sufficient. Because of the success of the flak batteries in Spain and the influence of Douhet’s theory of attack, as well as Hitler’s belief that the noise and the flash of the batteries had a salutary political and psychological effect on civilians. the Luftwaffe rested defense of the Heimat (Homeland) on these 88mm batteries, and manufactured fighters and bombers heavily weighted in favor of the latter. 40 percent of the pre-war Luftwaffe units were bombers and dive bombers and only 25-30 percent were fighters.[94] In the short-run this imbalance of fighters and bombers was not a problem in Spain. But in the long-run, it subjected Germany to the “strategic” bombing envisioned by Douhet. Once again, the German military aptitude for brilliant short-term tactical problem-solving undermined the long-term strategic planning imperative to the successful prosecution of war.

Summary of the Luftwaffe Lessons from Spain

From the broadest perspective, the Condor Legion intervention in the Spanish Civil War quickened the pace of rearmament in Germany. As Edward Homze states, the war “encouraged the Reich leadership to speed up the introduction of new models as rapidly as possible even though reductions in total output and a vast increase in expenditures would result. The Spanish Civil War, coupled with the Austrian and Czech crises of 1938, also removed the last vestiges of resistance in the more conservative camp that argued for a slowdown of rearmament."[95]

At peak strength in Spain in the late summer of 1938, the Condor Legion had 40 Heinkel He 111s, 3 Junker Ju 87s, 45 Messerschmitt Bf109s, 5 Dornier Do 17s, 4 He 45s, 8 He 59s and 8 batteries of light and heavy flak.[96] In addition, the Nationalist air units at that time contained 146 Spanish and 134 Italian planes. Upon returning to Germany in May 1939, the Condor Legion counted 281 officers, 4,383 men, and 4l2 civilian technicians. In total, approximately 19,000 Germans served duty in Spain. The Legion shot down 386 enemy aircraft, of which 59 were downed by the anti-aircraft batteries. The Germans lost 72 aircraft by direct enemy action and 160 through accidents. In terms of lives, 298 Germans were killed while serving in Spain; 131 were killed by the enemy and 167 died from illness and vehicular accidents.[97] Those wounded by the enemy totaled 139. Though a comparatively small price to pay in relation to what the Luftwaffe hoped to gain, German losses were substantial because of the diminutive size of the youthful air force and the materiel constraints imposed by the German economy and military-industrial complex on aircraft production.

In the concrete realm of day-to-day operations, the Spanish War furnished a mother lode of knowledge, although at time; this knowledge was misapplied. The combat experience gained by Condor Legion pilots was invaluable particularly because many of these pilots became instructional officers in pilot training schools in Germany.[98] The pilots also learned the importance of detailed maps, the benefits from rapid, positive target identification and the need for adequate radio communications.[99] As a catalyst for the development of technology, the conflict emphasized the value of weather forecasting. radio directional systems (i.e. Knickebein), the use of pathfinder aircraft, and incendiary flares for effective night bombing. With regard to aircraft. Spain was a very helpful testing ground and incubator. The He51 biplane demonstrated its obsolescence as a fighter when matched against the Russian monoplanes and fruitfully exchanged that role for one of close ground support. The Ju52 proved an extremely reliable transport aircraft but a limited bomber, so it too assumed a role it was to fulfill more than adequately. During the course of 1937, the Bf109 fighter, the Ju87 Stuka dive bomber and the He1 l l and the Do17 bombers were introduced in Spain and all showed their value as combat aircraft.

The mistakes engendered by the Spanish War, more than the successes, indicate the difficulty in drawing general conclusions from an unusual and specific conflict. Because Legion bomber squadrons rarely encountered much opposition after the Nationalists attained air supremacy, the introduction of the He111 fast bomber suggested incorrectly that bombers required only a light armor and little fighter protection. The high command mistakenly believed that bombers could rely on speed alone to penetrate the enemy’s defenses.[100] Berlin failed to perceive that even high performance, well-armed bombers in mass formation could not protect themselves against detetmined fighter opposition, particularly dluring daytime missions. This oversight caused the Luftwaffe to neglect the coordination of fighter and bomber development. After realizing that bombers needed fighter escorts. the Luftwaffe command discovered that their fighters lacked the range to protect the bombers during the missions. A similar nearsighted rationale approved of the concept of an all-purpose aircraft for strategic and tactical operations. Indeed, Hitler demanded that heavy, multi-engined bombers possess both a strategic and dive bombing capability.[101] The resulting hybrid aircraft, the Ju88, was unable to carry out either mission properly. The success of the 88mm flak guns in Spain suggested that flak cannons wete the best weapon for air defense, and that therefore little attention need be paid to a fighter defense system to protect Germany. The horrific losses inflicted on Germany by USAF and RAF bombers attest to the inaccuracy of this belief. The most valuable lessons taught in the laboratory of the Spanish War was the tactical concept of combat operational doctrine. The Spanish experience established within the Luftwaffe the belief in close ground support tactics as the preeminent and foremost task of the German air force. This belief produced both the Luftwaffe’s most spectacular success in Poland and later contributed to the Third Reich’s utter defeat.

The Polish Campaign (1 September — 27 September 1939)

In many ways, the Polish campaign justified the principles which had been enumerated and developed in Spain. The first of these principles was the concentration of all available effort on one task at a time. The second principle was the elimination of any obstacle that might hamper the movement of the ground forces.[102] The German Air Staff planned the military operations against Poland, Fall Weiß (Case White), largely according to these principles, and was rewarded with a spectacular success.

The strategy and tactics applied in Poland to implement the two principles elucidated above were taken from Condor Legion experience in Spain. Basically, the Luftwaffe supported infantry, and mechanized armor units, clearing the path of obstacles and seeking to achieve air superiority. The Polish Campaign demonstrated the efficacy of the lessons learned in Spain: close ground support tactics, air transport, and dive bombing. The Polish Campaign also provided the first opportunity to combine the full might of the Army and the Luftwaffe. Blitzkrieg (lightning war), as this new type of warfare was termed, was the close cooperation between tactical air and mechanized ground formations to penetrate deeply and rapidly into enemy territory.[103] The basic elements of Blitzkrieg had been developed in Spain. In Poland, they were fully implemented for the first time.

Prior to the attack on Poland, the Luftwaffe comprised 370,000 men grouped in three unequal divisions. The air force alone had 208,000 men, of which 20.000 were aircrew and 1,500 were paratroopers. The flak had 107,000 men, and the air signal units 58,000 men.[104] The Luftwaffe had amassed over 2000 aircraft in preparation for Fall Weiß, a number far in excess of the Polish Air Force’s 500 mostly obsolete fighter planes.[105] Of the German aircraft,1000 were bombers and 1050 fighters. Despite the Spanish Civil War, the Luftwaffe was not prepared to embark upon a campaign against Poland, or any other country for that matter. In September 1939 the Luftwaffe had stocked only enough bombs for three weeks and ammunition for six weeks.[106] Moreover, the Luftwaffe lacked a long-range strategic bomber, an adequate night bomber, bombs heavier than one thousand pounds, air torpedos, rnodern mines. modern armament, and accurate bombsighs. Bombers and escort fighters still lacked the means to communicate with one another.[107] Luckily, the campaign against Poland was short. It did not last long enough to reveal Germany’s underlying inventory and supply weaknesses. nor did it fully test the limited capabilities of a still unprepared Luftwaffe.

Within the context of the overall German military strategy of Fall Weiß, the Luftwaffe’s first and foremost objective was the destruction of the Polish Air Force in order to attain air superiority.[108] Only with the attainment of air superiority could the Luftwaffe hope to provide unhampered support of the Army. As part of this objective, the Luftwaffe was to dislocate the entire Polish Air Force support, supply and organization and to disrupt the Polish aircraft indusuy. Secondarily, the Luftwaffe would take part in the destruction of the Polish Army by bombing and strafing strong points. artillery batteries, and concentrations of ground troops. The combination of planes and mechanized ground units of the Army was to prove extremely successful, as the course of the campaign illustrated.

The German attack against Poland began at 4:45 AM on 1 September 1939.[109] Fog and low cloud cover delayed the morning air operations, but by afternoon, the Luftwaffe was heavily comitted. The Luftwaffe’s primary targets were Poland’s airfields. Those at Kattowitz, Krakow, Lwow, Lublin, Wilna, Kida, Glodno, and others received a thorough pounding. The out-dated Polish P.Z.L. P.11 fighters which managed to take off were easily intercepted and repulsed by the Bf109s and Bf110s.[110] Nevertheless, the Polish pilots exhibited great courage and determination in the air. The Germans did not know, however, that the Polish planes that rose to meet them were decoys fighting a feinting action. Though the Luftwaffe had hoped to catch all of Poland’s planes on the ground, Polish intelligence had discovered signs of the imminent German attack, and the Polish Air Force had transferred most of its operation aireraft to camoufiaged emergency aitstrips.[111] The Germans naturally attacked Poland’s well-known permanent airfields. Thus, they succeeded only in destroying outmoded fighters and a number of training craft not immediately serviceable. The bulk of the Polish Air Force escaped, giving the Polish Air Command time to improvise a plan for the defense of Warsaw.[112]

On the assumption that it had obliterated the Polish Air Force, the Luftwaffe shifted part of its efforts on 3 September to secondary targets and operations in support of the army. These operations followed the plans laid out prior to the campaign. The Luftwaffe bombed and strafed strong points, artillery batteries, and troop formations. To dislocate enemy supply organization, the bombers focused on factories, barracks, ammunition dumps and depots. Further behind enemy lines, aircraft attacked railway stations, bridges, tracks, and road junctions to disrupt communications and to prevent the Poles from moving up reinforcements.[113]

Cooperation between the air force and the army was excellent, due mostly to Wolfram von Richthofen.

So concerned was Richthofen with providing the army with what it needed from the air that he offered to share his quarters and command post inside Schönwald Castle, six miles from the front, with General Walther von Reichenau, commanding the l0th Army. It was a happy arrangement, for Reichenau’s armor was scheduled to punch holes in the Polish defenses while Richthofen’s ground attack formations blasted a clear path ahead. This was interservice cooperation at its closest, a thing Richthofen had learned to value while dealing with some of Franco’s generals in Spain.[114]

Richthofen also stayed current on the ground situation by stationing himself as close to the front as possible. Whenever feasible, he flew over enemy territory in his Fiesler Storch to engage in personal reconnaissance. Indeed, on the first day of the attack, he was downed by anti-aircraft fire, but he crash-landed and returned unharmed. Aside from his own fly-overs, Richthofen had at his disposal specially equipped signal units and a reconnaissance squadron to fumish him with timely intelligence information.[115]

The Battle near Kutno from 9-18 September is a good example of the effects produced by the Luftwaffe in Poland. Under General Kutzreba, the commander of the Army of Poznan, the Poles successively launched a surprise attack in the area around Kutno. To counter the Polish Army’s movement, the Luftwaffe was called in to blunt the attack. Thirty Henschel Hsl23s swarmed over the Army of Poznan at low levels, utilizing their wide range of armaments to bomb, strafe, and generally disrupt the enemy troops.[116] The Hsl23s were followed by Stukas, Dorniers, and Heinkels. The attack was so demoralizing that some of the Polish troops threw down their weapons and fled.[117] On 18 September 50,000 Polish troops surrendered and on the next day, another 105,000 capitulated. Herbert Molloy Mason Jr. describes vividly the inferno inflicted on the Poles.

To Kutzreba’s men, almost none of whom had been under air attack before, the next twenty minutes were like a nightmare in hell. The machine guns cut swaths in the ranks of men and horses; hundreds of light weight scatter bombs flamed and exploded; the heavier detonations of the 110-pounders tore gouts out of the earth, ripped through trees and flung jagged metal shards thudding into men and animals. Even when the last of the various missiles had been delivered, the 123s were not finished with low-level attacks. The pilots discovered that when the BMW engine was pushed to 1800 r.p.m., the resultant effect on the three-bladed, variable pitch airscrew produced an ear-splitting and indescribable sound that was both inside and outside of the man subjected to it. Even hardened soldiers were unnerved, and ran in all directions to escape. Horses simply went insane.[118]

The Polish planes so cleverly removed before the surprise attack to be used in the defense of Warsaw, never stood a chance against the Luftwaffe’s overwhelming numbers. In the skies above the capital, Polish P.Z.L. P.11 fighters rose to meet the Bf109s, only to be outgunned by the faster and more maneuvernble German aircraft. Occasionally, a Polish pilot by dint of bold determination, shot down an enemy fighter or bomber, but for the most part, the Polish fighters succumbed in the face of the larger numbers, the greater firepower, and the more modern equipment of the Luftwaffe fighter force.

Before bombing the Polish capital, the Luftwaffe dropped thousands of leaflets, requesting the city’s surrender. When the request was refused, the Luftwaffe’s bombers went into action. Thereafter, the skies over Warsaw were never clear of German aircraft as the Luftwaffe bombed the city. The operation began on 23 September with swarms of Stukas stacked up in groups several thousand feet apart, diving in systematic relays on the city. Following the dive bombers, Ju52 transport planes, jury-rigged to serve as bombers, blasted the city as crewmen literally shovelled loose themite incendiary bombs out of the cargo doors.[119] No city or people could withstand such a devastating attack, and on 27 September 1939 the Polish Government surrendered the capital.

Despite the success of the Luftwaffe, it was the Army which accounted for the quick and overwhelming German victory in Poland. The Army’s rapid advance overrun the Polish early warning systems and forward bases, preventing a coordinated direction of Polish fighter aircraft. The army’s advance also engulfed depots and dumps, thereby cutting off the supply of spare parts to the remaining operational Polish aircraft. It was not until 14 September that the Luftwaffe succeeded in surprising most of the Polish bombers at an airfield near Hutnicki.[120] The Polish Air Force was broken primarily by internal collapse, not external pressure. The Luftwaffe’s major contribution was not so much the destruction of the outmoded Polish Air Force as it was the effective close support of ground troops and the destruction of the Polish Army.

Fall Weiß proved a costly campaign for the Luftwaffe. Of the 10,761 Germans killed during the campaign, 189 were pilots and aircrew. 261 aircraft of all types were lost — 7.6 percent of the Luftwaffe force structure — mostly to anti-aircraft defenses against close ground support operations.[121] Among these 261 aircraft were 47 Bfl09s (5.6 percent of force structure). 81 bombers (6.5 percent of force structure) and 50 close support craft (13.2 percent of force structure). In Poland, the Luftwaffe suffered grave, though not irreparable damage.

The Polish campaign showed beyond doubt the value of the lessons learned in Spain. The Ju52s demonstrated their utility as transport aircraft, supplying the Wehrmacht’s Panzer (armor) and mechanized units, and providing the Bf109 squadrons with spart parts, ammunition, and aviation fuel.[122] Carpet-bombing was practised occasionally, as at the Krakow airfield by 60 He111s.[123] The He111s were followed by the plane that conclusively proved its worth in Poland, the Ju87 dive bomber. At Krakow, thirty Ju 87s plummeted down upon the airstrip to unload over thirty tons of bombs on hangars, parked aircraft, and runways. The Ju87 achieved astounding results because the Polish Air Force mustered little opposition to hamper it. Lacking effective opposition, the Stukas were able to exploit the very high inherent accuracy of the steep diving attack while simultaneously demoralizing the infantry with their piercing sirens.[124] The Stukas' success reinforced the belief among the German High Command that the airplane should be used primarily for ground support.[125]

The overall result of the Polish campaign was to entrench firmly the notion within command circles that the air force was an exceedingly powerful weapon. At the time, much was made in the press and elsewhere of the vital role played by the Luftwaffe and the new type of Blitzkrieg war made possible by the air force. The success of Fall Weiß was overwhelming, perhaps deceptively so.

The Polish Air Force was outdated and outmoded, and those planes which managed to get airborne were outnumbered by the Germans almost four to one. Yet the campaign led to wild claims regarding the Luftwaffe’s ability. In retrospect, such declarations accounted in part for Göring’s claim prior to Dunkirk that the Luftwaffe alone could win the battle, and perhaps the war. Albert Kesselring wrote,

Beyond all other military arms, the Luftwaffe, by virtue of its mobility in space accomplished tasks which in former wars had been inconceivable … The Polish Campaign was the touchstone of the potentialies of the German Air Force and an apprenticeship of special significance. In this campaign, the Luftwaffe learned many lessons … and prepared itself for a second, more strenous and decisive clash of arms.[126]

Denmark and Norway (7 Apri1-10 May 1940)

After Fall Weiß the warring countries entered a period that became known as the “Phony War.” Military engagements occurred infrequently. During this time, the Luftwaffe units that had participated in the Polish campaign returned to their bases in Germany. Aircraft were repaired, serviced, and refitted. and the air force continued to expand in anticipation of the spring campaign in the West. Luftwaffe operational activity was reduced to a minimum, restricted to occasional bombing runs on shipping and reconnaissance sorties. Fighter units, especially those stationed near France’s highly touted Maginot Line, were discouraged from engaging in combat.[127] The Luftwaffe was concerned primarily with repairing the damage suffered in Poland and preparing itself for the next attack.

In the spring of 1940, the Phony War ended abruptly. Instead of pushing westward, Germany launched a surprise attack northward against Scandinavia. The attack was intended to pre-empt British plans to secure Scandinavia as a military base as well as to protect crucial iron ore imports from Sweden.[128] Furthermore, the Germans wished to gain Scandinavia for themselves as a strategic base for future air and naval attacks on the British isles.

Luftwaffe strategy for Weserübung (Exercise Weser), as the campaign against Norway and Denmark was code-named, was based on the same two principles that had dictated the course of action in Poland. Denmark, bordering Germany’s northernmost province of Schleswig-Holstein, presented much less of a problem than Norway. Norway had a lengthy coastline that made the country easily accessible to intervention by the Royal Navy. As a result of these concerns, Germany needed to act covertly and with complete surprise. For the first time in modern warfare, paratroopers were used to achieve this element of surprise. Notwithstanding some tactical innovations, the Luftwaffe’s first goal was still attainment of air superiority followed by support of the army. Once these objectives had been accomplished, the Luftwaffe could begin its secondary tasks: supply and reinforcement of ground and motorized units, reconnaissance of coastal areas, attacks on British naval forces, support of troops operating in Norwegian valleys, and protection by fighters and flak of territory already taken.[129]

The attack against Denmark and Norway began on 7 April 1940. Ju52s dropped airborne troops on the periphery af the Danish capital as well as at two airfields at Ålborg. Land forces crossed the Danish frontier at the same time as seaborne forces landed on the Danish coastal islands. Within several hours, King Christian X had ordered his troops to cease fire, awed by a display of Hellls and Dol7s flying in massed formations over Copenhagen.[130] Germany had conquered Denmark with the loss of only twenty men killed and wounded.

The attack on Norway, which began concurrently with the attack on Denmark, quickly became the focus of extensive military action. German troops occupied the towns of Bergen, Trondheim, and Narvik, but they encountered determined opposition from Norwegian troops. Paratroops dropped on Oslo overwhelmed harbor forts that had sunk the German heavy cruiser Blücher as she had entered the fjord. Luftwaffe bombers knocked out forts at Christiansand protecting the harbor entrance so that the Kriegsmarine (Navy) could land troops. Large numbers of Ju52s delivered airborne troops to the strategically vital airfields at Fornebu (outside of Oslo) and Sola (near Stavanger). Long range twin-engined Bf110 fighters escorted the lumbering Ju 52s, but opposition was slight.[l31] Much of the small Norwegian figher force, its equipment largely obsolete, was destroyed by attacks on the airfields that preceded the paratroop drops. The Germans soon occupied the airfields and rushed in additional reinforcements by air.

The operation did not continue unopposed. The Royal Navy stepped up pressure on the coastal towns occupied by the Germans. At Narvik the besieged Germans under General Eduard Dietl had to be supplied and then reinforced by air.[132] British troops landed at Narvik, Namsos, and Andalsnes on l5-17 April. The Luftwaffe was forced to redirect its efforts against the British landing, the amphibious transports, and their naval escorts. Level and dive bomber units mounted continuous sorties. In the face of negligible air opposition, they inflicted serious damage on the British force.[133] German control of the airfields, a result of their successful surprise attacks, was crucial to turning back the British landing force. Indeed, the British had to call off a direct seaborne attack on the Trondheim area because the fleet would have been subject to air attack.[134] The distances were too great for the RAF to maintain a sizeable air contingent, and this prevented the British from establishing a force inside Norway. Luftwaffe reconnaissance planes spied an attempt by the RAF to operate old Gladiator fighters from frozen lakes. Shortly, German bombers arrived, unloading explosives which broke up the ice and destroyed the landing surface. Towards the end of the campaign, a small number of Hurricanes appeared, but it was too late for them to have much of an effect on the fighting.

At maximum strength, the Luftwaffe in Norway (Fliegerkorps X) comprised over 700 aircraft There were 360 long-range bombers (He 111s and Ju88s), 50 dive bombers (Ju87s), 50 single-engined fighters (Bf l09s), 70 twin-engined fighters (Bf ll0s), 60 reconnaissance craft (Do17s) and 120 coastal types (He l115s, He 59s, Do l8s).[135] In addition to these aircraft, 500 Ju52s were made available for transport, supplemented by a small number of four-engined Ju90Bs [136] and Focke Wolf Fw200 Condors.

Throughout Weserübung, the Germans made extensive use of air transport to move, supply, and reinforce troops. Indeed, the primary function of the Luftwaffe in the seizure of Scandinavia was that of a transport service. The German expedition’s commander, General Nikolaus von Falkenhorst, wished to execute a friendly invasion, and for this reason, the Luftwaffe’s role as an air shuttle service was emphasized. German air transport theory was fully and successfully tested. Other lessons learned during the Scandinavian campaign stressed the importance of fighter escorts for bombers striking targets protected by fighters. Air superiority was crucial, enabling the Germans first to establish and then to maintain troops in isolated and otherwise inaccessible areas. Furthermore, the Germans inflicted grave damage on the Royal Navy ships protecting the attempted seaborne landings at Trondheim. As Sims notes, “Air power properly installed and employed could force even the most powerful ships and navies from waters within aerial bombing range.” [137] The surprise occupation of towns like Oslo and Stavanger was made possible only by the use of paratroops and air-landed units. Air reconnaissance, carried out extensively over the broad reaches of the Scandinavian peninsula, facilitated communications in areas where roads were poor. Reconnaissance also pinpointed the location of the Royal Navy, enabling the Luftwaffe and the German Navy to sink several British transport- and warships.

In short, the Luftwaffe learned five lessons in Scandinavia. Paratroops and airborne operations rendered surprise easy, caused confusion among enemy troops, and invested the attacking German troops with the initiative; the air force intervened effectively in ground fighting in the rugged terrain of the peninsula; reconnaissance aircraft facilitated communications between pockets of isolated infantry and furnished accurate information on the where-abouts of enemy concentrations; air transport proved invaluable in delivering, supplying and maintaining troops from the air; and air power inflicted great damage on naval ships lacking aerial escort. Many of these lessons served well in the planhing of the next German move, an attack against the Low Countries and France.

Battle in the West (10 May — 26 June 1940)

The German attack against Holland, Belgium, and France began on 10 May 1940. The Luftwaffe arrayed over 4,000 planes against the Allies 1,700, a mismatch that to a large extent indicated the course of the battle. Against 1,680 bombers, France and England could gather only 830 fighters, while the Luftwaffe could put over 800 Bf l09s into the air to escort their bombers.[138] Of the total German planes available for the attack, there were 1,300 long-range bombers, 380 dive bombers, 860 single-engined fighters, 350 twin-engined fighters, 640 reconnaissance planes, 475 transport aircraft, and 45 assault gliders.[139]

For the fourth time in as many campaigns, the Luftwaffe’s role in the Battle against France and the Low Countries was primarily that of support and transport. Initially, the Luftwaffe was to gain control of the air. Then, it was to clear the way for airborne operations by powerful attacks on enemy airfields. In conjunction with airborne attacks, Ju52s were to tranport paratroops to their destinations. Subsequent to and subject to the success of these objectives, the Luftwaffe was to support the Wehrmacht’s armored thrust westward. Finally, the Luftwaffe was to supply the advancing mechanized and ground troops, keeping disparate forces in motion and in contact with command headquarters.[140] Hitler added, perhaps superfluously, that “the air force will prevent attacks by the Anglo-French air forces on our army and will give all necessary direct support to the advance.” [141]

The meticulously prepared and well-integrated attack of the German army and air force in the Low Countries was overwhelming. The Lifftwaffe bombed and strafed Dutch and Belgian airbases, destroying the meager and obsolete equipment those countries possessed. Luftwaffe paratroops seized bridges and road junctures, while glider forces assaulted the Belgian fortress of Eban Emad. This fortress, an underground system of fortifications manned by 1,200 Belgian soldiers and reputed to be impregnable, was besieged by 85 German assault pioneers until German reinforcements arrived on 11 May, forcing the garrison to capitulate.[142] The element of surprise was achieved by means of airborne gliders, which had been towed by Ju52s from Cologne and released over Aachen, 15 miles from the fortress.[143] At the Hague, airborne troops captured the three main airfields and took the important Moerdijk bridge near Rotterdam. However, a plan to capture the Dutch Royal family and government failed.[144] The Willems bridge, spanning the Meuse River in the center of Rottertlam, was seized in an unorthodox attack by troops landed on the river by He59 floatplanes. Holland surrendered on 15 May and the Belgian Army laid down its arms thirteen days later.

The focus of the battle then shifted towards France and the all-important Meuse River crossing. The west bank of the Meuse was strongly fortified, for the river marked the last natural boundary and impediment between the advancing German forces and the French countryside beyond. On 13 May at 4 PM, the Luftwaffe began to bombard French positions on the west bank. As the battle got underway, the Luftwaffe acted as a mobile artillery barrage, providing powerful and direct air support for ground troops. The French Air Force, in the process of converting to a new generation of aircraft, proved less than a match for the Luftwaffe. Operational ready-rates in the Armée de l'Aire squadrons were as low as 40 percent.[145] German reconnaissance gave the German High Command a detailed picture of the British and French forces. In the remaining hours before darkness, the Luftwaffe carried out over 500 sorties by dive and level bombers. As in Poland, when Richthofen had shared his quarters with the army’s General Reichenau to facilitate close interservice cooperation, General Heinz Guderian carefully worked out a plan ahead of time with General Bruno Loerzer, head of Fliegerkorps II (Air Force Corps II), to coordinate the attack.[146] The two men decided that continuous support by the Luftwaffe would best serve the troop movements. Continuous dive bombing attacks prevented French artillerymen from firing at the German infantry crossing the Meuse. By nightfall, the troops had established a bridgehead on the west bank.

An example of the devastation wreaked by the Luftwaffe took place at the town of Sedan, situated on the banks of the Meuse. On 13 May, Do17s accompanied by He111s unloaded explosives on the town for over four hours, demolishing telephone lines, roads, railroad tracks, and many buildings. Following the conventional bombers, Stukas stacked in layers dove on the city for a total of five more hours, dropping 500 pound bombs which penetrated reinforced bunkers, upended artillery pieces, and flattened barracks. The bombers were effectively guarded by Bfl09s and Bfll0s which fended off British and French fighters.

The following day, as the tanks prepared to cross the Meuse, Bfl09s shot down half of a French bomber squadron which had launched an attack on the pontoons spanning the river. A second attempt by the RAF Advanced Strike Force under Air Marshal Sir Arthur Barratt, with 71 Blenheims and Battles, and an assortment of 250 French Moranes, Curtisses, and Dewoitine fighters, suffered a similar fate. The attack was decimated by flak and Bfl09s which broke through the fighter screen to shoot down 40 bombers. In the aerial melee, 50 of the Allied fighters also perished. “No higher rate of loss in an operation of comparable size has ever been experienced by the RAF.” [147] The advancing German Panzers forced the French Army divisions to retreat and resistance along the river disappeared.

The rapid deployment of troops and equipment essential to the mobile warfare practiced by the Germans was made possible by the Ju52 transport planes. Fuel, spare parts, ammunition, and ground personnel were flown to their destinations because the Meuse bridge crossings were often congested. Thereafter, as the mechanized Panzer corps advanced, the supply lines lengthened dangerously. The Ju52s again played a vital role, transporting all the neccessary supplies. The lumbering craft themselves had to be moved forward to new airbases every day. The rapid German advance was indicative of the course of the fighting, which became a rout of the Allied forces.

As the German troops moved northwest towards the English Channel some 200 miles away, long-range bombers with fighter escorts attacked a broad spectrum of targets, from railway marshalling yards to all movements of the Allied armies. The French and British forces were subject to incessant bomber and fighter attacks, usually conducted at low levels to achieve surprise and accuracy. Bf109s and Bfl10s rained a veritable hail of machine gun and cannon fire on enemy troops. Bombers followed closely behind with explosives fused for a delay of several seconds to ensure ground level explosion.[148]

The French and British armies retreated towards the coastal town of Dunkirk. Göring pleaded with Hitler to permit the Luftwaffe to be the sole instrument of the Allied armies' destruction. Hitler acceded, and ordered General Guderian’s tanks to halt outside of Dunkirk. What followed was the first rebuff of the Luftwaffe in World War II. British fighters, operating closer to their bases than the German planes, could remain over the Dunkirk beaches for a longer period of time than the BFl09s and Ju87s. The Spitfire fighters proved a match for the snout-nosed 109s, and as a result, the Luftwaffe failed to achieve air superiority.[149] During the nine days between 26 May and 3 June, the Luftwaffe lost 240 planes to the RAF’s 177.[150] Poor weather also prevented the German fighters and bombers from achieving the prolonged concentration of attack essential to success.[151] Frustrated by the quantitatively and qualitatively equal British fighters, the Luftwaffe also discovered that bombing the beaches was ineffectual. “Dropping 110 and 550 pound bombs into the soft sand was like stuffing firecrackers deep into sawdust.” [152] To deprive the Luftwaffe of the visibility afforded by daylight, British and French troops were evacuated under cover of darkness. Countered at almost every turn, the Luftwaffe focused on the ships transporting the Allied armies across the English Channel. 243 of the 861 ships involved in the evacuation from Dunkirk were sunk by German bombers.[153] Nevertheless, the bulk of the Allied troops escaped -338,226 men — and the Germans had to be content with the mass of equipment left behind.

Although France capitulated on 26 June 1940, the Luftwaffe’s failure over Dunkirk contained ominous signs for the future aerial attack on Britain. Yet, the air doctrine applied by the German Air Force in the last continental campaign of 1940 had not been rendered invalid. The air support throughout the 46 day battle was fundamentally a large scale application of the lessons learned in Spain and improved in Poland. The validity of those lessons was, if anything, strengthened. The Luftwaffe successfully attained air superiority until Dunkirk, and control of the air proved to be an element essential to the success of the ground troops. The Luftwaffe followed through on its close cooperation with the mechanized ground forces, delivering, supporting, supplying, and reinforcing paratroops and infantry. The reputation of the Stuka was further enanced in the campaign. as it destroyed enemy dugouts, fortifications, pill-boxes, and tanks with frightening accuracy. The potential logistical problems brought about by the rapid advance of the army was averted by the dependable Ju52 transport plane.

Luftwaffe failures in the West taught the Germans that formations of unescorted bombers could not survive in the face of a well-equipped and determined fighter opposition, such as the British mustered over Dunkirk. The German bomber crews who believed their Do17s to be as fast as British fighters, and were therefore possessed of a reasonable chance of success in a dogfight, were quickly disillusioned.[154] The German fighter crews also realized that the twin-engined Bf110 could not confront the single-engined British fighters.[155] The Luftwaffe had been dealt a sobering lesson at Dunkirk. This lesson was soon followed by an even more disastrous defeat in the skies over the British Isles.

Conclusion

Despite the Luftwaffe’s failure over the beaches of Dunkirk, the lessons derived from the Condor Legion experience in the Spanish Civil War were not invalidated. Rather, the aerial battles over Dunkirk finally revealed that some of the lessons the Luftwaffe drew from the Spanish War experiences had been misinterpreted and misapplied.

Luftwaffe air warfare doctrine was encapsulated in Luftwaffedienstvorschrift 16: Luftkriegsführung. Throughout the course of the Spanish War and the campaigns in Poland, Scandinavia, the Low Countries, and France, the Luftwaffe adhered faithfully to three basic air warfare rules. The first was the subjection of the enemy air force and the attainment of air superiority. Second was the support of the army and the navy (especially of the army). Third was the destruction of the enemy’s industrial base and the disruption of his means to wage war.

In Spain, the Condor Legion followed only the first two rules. Spain had very little industry, and the nature of the civil war often precluded attacks on Spain’s meager industrial base. Nevertheless, the application of these two rules resulted in success, and within the context of those rules, tactics were conceived and bore fruit. Close ground support tactics were developed by Wolfram von Richthofen. Fighter tactics evolved, primarily under the tutelage and perseverance of Werner Mölders. Daylight bombing, night bombing, dive bombing, and naval bombing were practiced and refined. The Condor Legion learned and absorbed the advantages afforded by mobility and rapid deployment of men and equipment. The structure and organization of the Condor Legion was rationalized and improved. When the Condor Legion returned to Germany in March 1939, it brought with it experienced pilots who taught and trained new Luftwaffe recruits. Inevitably, the Condor Legion brought back to Germany combat lessons and field experience which nourished the minds planning the next Luftwaffe campaign, the assault on Poland.

The Polish campaign demonstrated on a larger scale the value of the lessons learned in Spain. As in Spain, the Luftwaffe concentrated on destroying the enemy’s air force and attaining air superiority. This accomplished, the Luftwaffe proceeded to the second rule, support of the army. The Blitzkrieg, first employed in Poland, combined mechanized Panzer units and air power to devastate the Polish Army. Reflecting the rapidity of the German advance, the Poles surrendered after four short weeks, their army and air force crushed. The Luftwaffe’s major contributions were close ground support tactics, dependable air transport, and accurate dive bombing. Luckily for the Luftwaffe, the Polish Campaign was too short to reveal its supply and equipment deficiencies. Nevertheless, its strategy and tactics proved spectacularly successful, and it had time to recuperate before the next campaign.

The Weserübung against Scandinavia followed the basic pattern established in Poland. The Luftwaffe quickly attained air superiority and used paratroops for the first time in modern warfare to achieve complete surprise. The Luftwaffe then supported the German ground forces, providing reconnaissance and transport services to bolster the army’s assault. By the end of the campaign on 10 June, the Luftwaffe had learned the importance of fighter escorts for bombers, the ability of air power to force naval ships from waters within aerial bombing range, the necessity of air reconnaissance, the surprise rendered by airborne asault, and the positive services provided by air transport. These lessons formed the foundation for Germany’s last continental victory.

Against Holland, Belgium, and France, the Luftwaffe applied its well-tested air warfare doctrine, again achieving success. Gliders delivered airborne troops, an innovation which enabled 85 men to capture the fortress of Eban Emael. The army and air force cooperated closely, relentlessly forcing the Allied army to retreat. The French Air Force, like the Polish, Norwegian, Belgian and Dutch air forces before it, failed to halt the Luftwaffe, while suffering grievous losses trying. At Dunkirk, the Luftwaffe was finally rebuffed by the Royal Air Force, which enjoyed qualitative and quantitative equality.

Over four years, the Luftwaffe showed the world air power unexcelled. The essense of its strategy was air superiority. Without superiority in the air, troops could not be easily transported, motorized ground units could not move rapidly, enemy troop concentrations could not he disrupted, and enemy fortifications and communications could not he destroyed. When the Luftwaffe failed to attain air superiority, as at Dunkirk, it failed to win. The lessons learned in Spain, and enlarged and elaborated in the succeeding European campaigns, were faithfully though not always correctly applied. After the fall of France, the Luftwaffe’s neglect of heavy bombers, long-range fighters and radar manifested itself. The British began to outproduce the Luftwaffe, and the Russian quagmire swallowed entire squadrons. There can be no question that the Spanish Civil War decisively affected the development of Luftwaffe operational doctrine. There can also be no question that initially, the result of that doctrine was success, demonstrated as the Luftwaffe rendered indispensable assistance in the triumphs over Germany’s enemies. At the same time, the Luftwaffe’s deceptively easy victories hid the seeds of its defeat. Although this defeat was a long time in coming, often masked by brilliant German inventions and innovations, come it did. Like the air forces it had helped vanquish, the Luftwaffe too learned defeat.

Notes

Bibliography

Primary Sources

• Bekker, Cajus. The Luftwaffe War Diaries. Ed. and Trans. Frank Ziegler. Garden City, NY; Doubleday & Company, Inc., 1968.
• Eichelbaum, Hauptmann Dr. (E). Die Deutsche Luftwaffe: Ein Bilderwerk. Berlin: Junker and Dünnhaupt Verlag, 1940.
• Eichelbaum, Hauptmann Dr. (E). Die Lüftmächte der Welt: Ein Bilderwerk. Berlin: Junker und Dünnhaupt Verlag, 1939.
• Mayer, S.L. and Tokoi, Masami, eds. “Der Adler": The Official Nazi Luftwaffe Magazine. New York: Thomas Y. Crowell Company, Inc. 1977.
• Trautloft, Hannes. Als Jagdflieger in Spanien. Berlin: Albert Mauck & Company, 1947.

Secondary Sources

• Alegi, Gregory. “Italian Fighters in the Spanish Civil War.” Yale University term paper, History 428b, Spring 1985.
• Andrews, Allen. The Air Marshals: The Air War in Western Europe. New York: William Morrow & Company, Inc. 1970.
• Beevor, Antony. The Spanish Civil War. New York: Peter Bednek Books, 1982.
• Collier, Basil. A History of Air Power. New York: MacMillan Publishing Company, Inc., 1974.
• Deichmann, Paul. Der Chef im Hintergrund: Ein Leben als Soldat von der preußischen Armee his zur Bundeswehr. Hamburg: Stalling Verlag GmbH, 1979.
• De Seversky, Major Alexander P. Victory Through Air Power. New York: Simon & Schuster, Inc., 1942.
• Faber, Harold, ed. Luftwaffe: A History. New York: Quadrangle/The New York Times Book Company, Inc., 1977.
• Frank, Willard C., Jr. “Naval Operations in the Spanish Civil War, 1936-1939.” Naval War College Review, January-February 1984, pp. 25-55.
• Galland. A., K. Ries and R. Ahnert. The Luftwaffe at War, 1939-1945. Trans. D. & I. Dunbar. Ed. David Mondey. Chicago: Henry Regnery Company, 1972.
• The Rise and Fall of the German Air Force. 1933-1945. Intro. Air Commodore H.A. Probert. By the Great Britain Air Ministry. London: Arms & Armour Press, Lionel Leventhal Ltd., 1983.
• Gurney, Major (USAF) Gene. The War in the Air. New York: Crown Publishers, Inc., 1962.
• Halley, James J. The Role of the Fighter in Air Warfare. Ed. Charles W. Cain. New York: Ziff-Davis Flying Books, 1978.
• Homze, Edward L. Arming the Luftwaffe: The Reich Air Ministry and the German Aircraft Industry. 1919-1939. Lincoln, NE: University of Nebraska Press, 1976.
• Irving, David. The Rise and Fall of the Luftwaffe: The Life of Luftwaffe Marshal Erhard Milch. London: Weidenfeld & Nicolson. 1973.
• Jablonski, Edward. Terror from the Sky. Garden City, NY: Doubleday & Company, Inc., 1971.
• Kosin. Rüdiger. Die Entwicklung der deutschen Jagdflugzuege. Koblenz: Bernard & Gräfe Verlag. 1983.
• Larrazabal, Jesus Salas. Air War Over Spain. Trans. Margaret A. Kelley. Shepperton, Surrey: Ian Allen, Ltd., 1969.
• Macksey, Kenneth. Kesselring: The Making of the Luftwaffe. London: B.T. Batsford, Ltd., 1978.
• Mason, Herbert Molloy, Jr. The Rise of the Luftwaffe: Forging the Secret German Air Weapon, 1918-1940. New York: The Dial Press, 1973.
• Murray, Williamson. Luftwaffe. Baltimore, Maryland: The Nautical & Aviation Publishing Company of America, Inc., 1985.
• Murray, Williamson. “The Luftwaffe against Poland and the West.” Unpublished Article.
• Nowarra, Heinz J. Fernaufklärer 1915-1945: Entstehung, Entwicklung, Einsatz. Stuttgart: Motorbuch Verlag, 1982.
• Overy, Richard J. The Air War. 1939-1945. New York: Stein and Day, 1980.
• Price, Alfred (Flight Lieutenant). Pictorial History of the Luftwaffe, 1933-1945. London: Ian Allen, Ltd., 1969.
• Proctor, Raymond L. Hitler’s Luftwaffe in the Spanish Civil War. Westport, CT: Greenwood Press, 1983.
• Ries, Karl. Luftwaffen-Story, 1935-1939. Mainz, Verlag Dieter Hoffman, 1974.
• Sims, Edward H. Fighter Tactics and Strategy, 1914-1970. New York: Harper and Row, Publishers, Inc., 1972.
• Sims, Edward H. The Fighter Pilots: A Conparative Study of the RAF, the Luftwaffe, and the USAF in Europe and North Africa, 1939-1945. London: Cassel & Company, Ltd., 1967.
• Thomas, Hugh. The Spanish Civil War. Middlesex: Penguin Books, 1965.
• Völker, Karl-Heinz. Die Deutsche Luftwaffe, 1933-1945: Aufrau, Führung and Rüstung der Luftwaffe sowie die Entwicklung der deutschen Luftkriegstheorie. Stuttgart: Deutsche Verlags-Ansalt GmbH., 1967. Vol. XIII.
• Von Forell, Fritz. Werner Mölders. Flug zur Sonne: Die Geschichte des großen Jagdfliegers. Leoni am Stamberger Sec: Druffel Verlag, 1976.
• Weal, Elke C. Combat Aircraft of World War II. New York: Macmillan Publishing Company, Inc., 1977.