The campaign against the Soviet Union in 1941 began in the same manner, in what had now become standard Luftwaffe doctrine. The Russian Air Force was attacked with great effect, which resulted in the destruction of over 1200 Soviet aircraft by noon of the first day. Support was then shifted to aiding the army in making penetrations and providing Close Air Support to rapidly moving ground units. However, it quickly became evident that the Luftwaffe was not large enough to cover the extensive expanses of the battlefields on the eastern front. Even as early as 1941, Luftwaffe units were subject to frequent lateral movements on the front in order to provide Close Air Support to outnumbered German ground forces to allow them to maintain momentum.
By the end of 1942, the use of airpower along the front lines in direct support of the army no longer assured victory. Because of the increasing capability of the Soviets to re-supply and reinforce the front lines, the Luftwaffe began to shift its emphasis toward interdiction. Changes were made to make the tactical forces of the Luftwaffe more flexible. At the same time units became more functionally oriented. This new orientation led to the creation of such elements as night harassment squadrons, used against Soviet troop concentrations; anti-tank squadrons using Hs-129, Me-110, Ju-87 and Ju-88 aircraft; and railway interdiction squadrons using the Ju-88.
The backbone of the Luftwaffe’s tactical support inventory was the Ju-87 Stuka. This aircraft was a single-engine, fixed-gear dive-bomber crewed by a pilot and a rear-facing gunner. It was developed during the 1930’s by Ernst Udet, the head of the Air Ministry’s production division. Udet had been infatuated by dive-bomb tactics developed in the United States. The Stuka was built not so much for its load-carrying capacity or range but because of its accurate ordnance-delivery capability. It was accurate because it could withstand the steep dive angles necessary for pin-point bombing. The Stuka proved itself well in the role for which it was designed, but in later years of the war its limited speed and maneuverability became liabilities in the face of increased Soviet counter-air capability.
The aircraft which was to take the place of the Stuka was the FW-190. This aircraft was much more maneuverable, although it carried about the same bomb load as the Ju-87. One advantage of the FW-190 was the outfitting of some models with heavy caliber rockets, allowing the Luftwaffe to institute low altitude delivery techniques against concentrations of troops and supplies. These tactics decreased exposure to antiaircraft fire and greatly increased the survivability of the FW-190 as compared to the Stuka. Later versions were equipped with 30mm cannon and given a purely anti-tank role. However, production was not started on the FW-190 until late 1941 and then only in an air-to-air version. Despite its effectiveness, it was not delivered to ground attack squadrons until just before the Battle of Kursk, and then in limited numbers.
The Henschel Hs-129 was a twin-engined aircraft designed as a tank destroyer. It was heavily armored and heavily armed with from 30mm up to 75mm cannons. The 75mm gun fired a round with a weight of 26 pounds, capable of penetrating any armor. Hs-129 squadrons were responsible for repulsing the attack of an entire Russian tank brigade during the Battle of Kursk. However, as was the case with many German aircraft by the end of the war, increased numbers of Soviet aircraft made the Hs-129 extremely vulnerable to the point where per mission losses were excessive, sometimes running as high as 20%.
Two bombers made up the remainder of the Luftwaffe’s direct support forces. The first, the Ju-88, was a twin-engined bomber served by a crew of four. It could carry a bomb load almost three times that of the FW-190 or the Ju-87 and was equipped with 30mm cannon on some versions. The second bomber, the Heinkel He-111, also had two engines but one more crew member than the Ju-88. The He-Ill was significantly slower than the Ju-88 and had shown itself to be vulnerable to fighter attack as early as the Battle of Britain. These two bombers were used in this role mainly due to the lack of sufficient numbers of ground-attack fighters. By late 1943 both were switched back to the mission of strategic bombing.
A point here about equipment needs emphasis. The Luftwaffe’s slowness in developing and fielding the ground-attack version of the FW-190 was a significant error. The Ju-87 needed a minimum ceiling of 2600 feet to operate effectively. This limitation often denied ground forces support in time of poor weather. Additionally, the high altitude approaches required made dive bombing a highly vulnerable tactic in the face of effective antiaircraft fire. In fact, as early as 1934 von Richtofen had stated that advances in antiaircraft made dive bombing techniques “complete nonsense.” Until the Battle of Kursk, however, the Luftwaffe had been very successful with the Ju-87. Therefore, they neglected the FW-190 as a ground-support aircraft and the warnings of von Richtoffen as well.
The Luftwaffe was also ill-prepared to face the Soviets with regards to the proper types of munitions. Standard high-explosive bombs were not effective in stopping heavily armored vehicles and tanks. Rapid work was done to improve and deploy ordnance with penetrating capability such as cannon and shaped-charge munitions. This development was somewhat successful, although the fitting of a particular weapon to an aircraft was often done in an improvised manner as exemplified when external cannons were mounted on the Stuka. The result was a decrease in speed and maneuverability in an aircraft already lacking in these critical areas.
Headquarters were organized two different ways. Initially they were assigned directly to the Army Command. In such cases the army decided the tasks to be carried out; however; the Luftwaffe staff made all decisions regarding mission execution, This concept was modified in 1942 in order to give the Luftwaffe more operational control over its own forces. After that time, Air Fleets were attached by air liaison office to the army command, normally at the Army Group level. This new system economized on the size of Luftwaffe staffs. An attempt was still made to align an Air Fleet to each Army Group’s area of operation.
Luftwaffe personnel were trained early in their service in the intricacies of providing tactical support to the Army and in army tactics in general. These tactics were taught at the Luftwaffe Air Command and General Staff College as well as in other joint schools. There was also a separate dive-bomber school which specialized in the tactics of providing Close Air Support, Training doctrine always emphasized that the Luftwaffe was designed to attack the enemy’s rear areas in the interdiction role. In the field, the army maintained an instructional staff at Luftwaffe units to keep them well briefed on the latest ground tactics. Additionally, many tactics bulletins were disseminated, giving the views of senior Luftwaffe and army tacticians.
By mid-1943, the doctrine embraced by the Luftwaffe was a modification of that which had been originally printed in Air Field Manual No. 16. As late as the eve of the Battle of Kursk in July 1943, interdiction was considered by Luftwaffe leaders to be the most decisive mission for airpower and this point continued to be stated doctrine. Attacks were to disrupt the enemy’s flow of supplies, troops and equipment to the front. Since these targets would be large and concentrated they would prove to be extremely vulnerable to attacks by the Luftwaffe. Attacks along the front were to be avoided since the targets there were necessarily dispersed and would not provide good results. Finally, Luftwaffe commanders felt airpower used to improve force ratios of ground units was to be avoided at all costs since such use was least effective. This last mission was later to become the one most commonly assigned to the Luftwaffe at Kursk.
The planning for Battlefield Air Interdiction missions was begun at Army Group – Air Fleet levels where the Luftwaffe’s capability to carry out a mission was analyzed. If the Luftwaffe staff determined that the mission was within the capability of the Luftwaffe, the mission statement was issued. The assignment of specific missions was accomplished by the flying units themselves. The combination of fighter-bombers and fighter escorts was determined by the Air Fleet staff based on aircraft availability and the status of the Soviet threat. The Luftwaffe operated under the overall tactical principle that once a target was engaged it would be engaged by multiple attacks until it was destroyed. Therefore, extensive use of aerial reconnaissance continued. Dive-bombers were generally assigned point targets which required greater accuracy, while low-level attacks were used against area targets. It was also felt that low-level attacks could produce the extra benefit of affecting the enemy’s morale.
Timely engagement of interdiction targets was critical. By early 1943 the Luftwaffe realized that strikes at interdiction targets would have an effect on the front line siguation within a few days. Soviet strategy all along the eastern front was to fight a battle in one area and then shift emphasis to another. Lateral mobility became an extremely important factor in Soviet and German plans. By 1943 interdiction became essential in combating the lateral movement of Soviet forces. Later in the war, notably after the fall of Orel in August 1943, the inability of the Luftwaffe (and the entire German war machine for that matter) to move rapidly to counter Soviet thrusts would prove to be decisive to Soviet victory.
The Soviets were fond of massing troops in large concentrations close to the front lines in preparation for any operation. In 1941, the Luftwaffe often engaged Soviet troop columns in excess of 100 34 yards wide. However, the best target was the Russian rail system. This was true for a number of reasons, of which the lack of an effective road system over which large amounts of heavy equipment could be transported was primary. Rainy weather often made the few available roads impassable. The Luftwaffe had initial problems in determining the correct way to go about interdicting rail traffic. Luftwaffe planners assumed that interdiction of single track routes where no bypass could easily be constructed would be most effective. For this reason transshipment points and railway depots were neglected. Later, however, it was discovered that rapid repairs could be made to sections of track along primary routes with relative ease. In fact, the only real result of attacks made on track was the tying up of a great deal of Soviet manpower in prepositioned sites as railway repair crews. Attacks on transportation centers were more successful since they usually destroyed a certain amount of supplies and equipment and effectively cut routes for a longer period of time. One drawback was that such critical areas were easier to defend and Soviet antiaircraft often took a heavy toll. A Soviet air defense officer at the time confirmed that Russian air defense fighters and the bulk of antiaircraft artillery were stationed very close to transshipment points like railway junctions. Another method of cutting routes on a more permanent basis was to concentrate on destroying railroad bridges. Bridges, however, were also easy targets to defend. (This was a lesson which the USAF was destined to relearn in attacks against the transportation system of North Viet Nam.) The most effective way of cutting the rail system was to attack locomotive repair facilities and the locomotives themselves. The Soviets attempted to deceive Luftwaffe pilots by instructing their engineers to release quantities of steam to simulate destruction. This tactic proved ineffective since the timing of the deception was critical. Luftwaffe pilots soon became adept at determining when a locomotive was truly hit.
The Luftwaffe developed an excellent system of studying areas of expected action ahead of time to determine the vulnerabilities of the rail transportation system. This information was then compiled into a publication entitled “Instructions for the Strategic Assembly and Conduct of Combat Operations.” This detailed study was coordinated ahead of time with the army so that German mobility would not be effected. Such coordination was not as important later in the war when movement of the front was generally east to west. What was especially noteworthy about this system was that it gave the Luftwaffe the option to plan action early and allowed timely attack of enemy concentrations and routes.
Certain realities prevented the Luftwaffe from carrying out a more extensive and effective interdiction campaign. Principally, by 1943 the Luftwaffe was tied to an overall strategy whose objective was to blunt Russian offensive action and force the Soviets to collapse due to heavy losses. To this purpose, Hitler decreed that battles of attrition were to be fought and forced the German Army to hold every piece of ground as if it were located in downtown Berlin. Defensive patterns were static and even encirclements were accepted in hopes that the Soviets would wear themselves out in such actions. Therefore, the Luftwaffe was tied more and more to the success or failure of the ground forces by bolstering the wall against which the Soviet forces would expend their might. Additionally, air superiority became more fleeting as Soviet air forces began to recover from the disasters suffered in 1941. Also, by 1943, the most experienced pilots were being drained from the eastern front to counter the air threat of the strategic attacks against Germany by forces of the RAF Bomber Command and the US Eighth Air Force. Consequently, less escort was available to allow fighter bombers to attack safely behind the front lines. Armed reconnaissance missions which had been successful under earlier situations of at least local air superiority could no longer be accomplished effectively. Such was the state of the Luftwaffe as it made preparations in early 1943 for the Battle of Kursk.