The development of German high-altitude fighters characterized the attitude of the German leadership to air battles on the Western Front. With the exception of the Battle of England, Northwest Europe remained until a certain point a peripheral theater of operations.
The attention of Hitler and the Luftwaffe leadership awakened only after the British raid on Cologne in May 1942. At the end of 1940, daytime air battles over southeast England gradually ceased. Only at night did Luftwaffe bombers continue to harass the air defense of Great Britain.
Both sides expected daytime raids to resume as the weather improved in spring, but this did not happen. Hitler now turned his gaze to the east.
In the summer of 1941, the British Air Force gave priority to the release of D. H. 98 "Mosquito", because after the invasion of German troops into the territory of the USSR, the British government badly needed information about the redeployment of the German army and navy.
Already in August, the first 10 serial "Mosquito" P. R. 1s were transferred to the 1st photo reconnaissance squadron in Benson for military trials, and in September the new scouts made their first combat mission. His route ran through Paris and the ports of Western France - Brest and Bordeaux.
In the very first sortie, the main trump card of this aircraft appeared - high speed at medium and high altitudes: three patrol Bf 109s, who tried to attack the reconnaissance aircraft at an altitude of about 7000 m, could not catch up with him. Since the spring of 1942, the squadron, completely rearmed on the Mosquito, operated from bases in England and Gibraltar over almost all of Western and Central Europe.
In the first months of 1942, at the insistence of the Luftwaffe, based on the experience of using air defense fighters, as well as intelligence information about the enemy's development of high-altitude engines and the increased production of superchargers for existing aircraft engines, the Technical Committee of the German Ministry of Aviation (RLM) began to study the possibility of creating a high-altitude fighter. It was supposed to be capable of intercepting the high-speed D. H.98 Mosquitoes, which were appearing in increasing numbers over the territory of the Third Reich and sometimes operating at altitudes almost inaccessible to German fighters.
In contrast to the Allies, Germany's attempts to develop a high-altitude engine were somewhat chaotic, since the Planning Department, despite intelligence information, was not interested in the development of such engines. At the same time, back in November 1941, Kurt Tank pointed out the need to produce high-altitude engines: “We tried all the ways to improve the high-altitude performance of the BMW 801, but it was clear that a completely new engine was needed. I already predicted that something like this might happen. In early 1941, before the FW-190 was put into service, I spoke with General Udet and Yesonnek regarding this issue. I said that they should put into production the Jumo 213 high-altitude engine, which was being bench-tested at the Junkers, so that we can have a ready-made high-altitude version of the FW-190 in case we need it. General Hans Jeschonneck, then Chief of Staff of the Luftwaffe, replied: "Why is this necessary? We do not conduct any aerial combat at such heights!" As a result, we lost about a year in the development of an efficient high-altitude engine, a time that we never made up for. In the end, we adopted a very good FW-190D high-altitude fighter with a Jumo 213. But he was ready too late - in the summer of 1944, but by that time Germany's air superiority had been lost."
At that time, the German industry produced in large volumes several basic types of engines: Jumo 211 for Ju-87, 88 and He-111, BMW 801 for FW-190 and Do-217, DB 601 for Bf 109, Me-110 and He -111.
All these engines satisfied the current needs, however, none of them was suitable for a high-altitude fighter, because the BMW 801, not to mention the "older types", had an altitude limit of 6800 m, and in fact, it had problems already from 5900 m Regardless of their views on the problem, Junkers and Daimler Benz began developing high-altitude engines. Junkers began designing a new version of the Jumo 213E, with a volume similar to the basic Jumo 213A (35 liters), but with an increased compression ratio and increased revs, and Daimler Benz initiated the development of a new DB 603 engine with larger pistons and displacement 45 l.
All the proposals put forward to improve the altitude of the engines can be divided into two groups. The first is schemes using the so-called emergency mode, for example, the GM1 nitrous oxide direct injection system (this system for increasing engine power was first mentioned by the Germans under the code name "ha-ha"), where nitrous oxide or "laughing gas" liquid state, was injected into the supercharger under pressure. The second - the most complex schemes of engines with separate pumping units.
In 1942-43, it was still doubtful that the problem could be solved by using a turbojet engine - the behavior of the turbojet engine at such altitudes had not been studied. Such information was not available until the beginning of 1945, when the corresponding research was carried out at the Junkers firm. The advantage of the piston engine during this period was that its characteristics had a fairly wide range, and the use of superchargers or systems that increase the engine's altitude further expanded the scope of application.
The DB 603 engine had a takeoff power of 1,800 hp. The development plan for this engine was rejected by RLM, which motivated its refusal by the fact that its implementation would entail major changes in the production of other necessary engines and the inevitable suspension of the design of new aircraft.
Despite the decision of the Technical Committee, Daimler Benz continued to build prototypes on its own initiative, based on experimental data from the DB 605 engine for the Bf.109G, designed for operations at medium altitudes.
At the turn of 1942-1943, on the basis of analytical studies, it was found that the development of a high-altitude engine with a capacity of 1000 hp. at altitudes of about 10,000 m, is comparable in labor costs to the design of a conventional motor with a power of more than 3600 hp (!) and that further development of high-altitude engines is very expensive. For this reason, the development of the high-rise DB 603 proceeded much more slowly than was necessary.
A similar situation developed for the Junkers with the Jumo 213E, the first prototype of which was tested only by the beginning of 1944, however, its serial production began at the beginning of the next year. The Jumo 213E and F engines were delivered to Focke-Wulf in the fall of 1944, and the DB 603E and L in January 1945 and only a few copies. The BMW 801 TJ was also handed over to Focke-Wulf in several copies and was used only for testing it in the air.
Prototypes of the newest aircraft engines: Jumo 222, 224, 225 and DB 628, with high power, could not be brought to the series, although some projects were developed for them, including the Focke-Wulf.
By the end of the war, the Germans had reached an extremely high level in engine building, especially in the field of creating systems for increasing power and automatic control devices. However, due to the most difficult military and, as a result, the economic situation, there were not enough modernized and newest engines, not to mention their high-altitude versions.
At the end of the summer of 1942, it was already clear that the American Air Force was going to concentrate significant numbers of bombers at British bases for strikes on the territory of the Third Reich. High-altitude flights of the B-17 in combination with the Halifax and Lancaster have already caused certain problems for the German interceptors. And new intelligence brought information about the serious intentions of the United States to organize the serial production of the most powerful B-29s with even more impressive speed and altitude characteristics. As a result, there was an urgent need for a high-altitude fighter.
At a meeting held in the spring of 1942, the RLM instructed the firms to announce its requirements for a new high-altitude "super fighter" (Hohenjager), also capable of performing the functions of a high-altitude reconnaissance aircraft.
The "super-fighter" program was divided into the following stages: "urgent" with the development of a fighter based on production aircraft with the maximum use of components and assemblies of base machines, and "postponed" - with the development of a new high-altitude fighter and reconnaissance aircraft.
Focke-Wulf began to implement this program, having some experience in creating the FW-191 high-altitude bomber, although it did not enter service with the German Air Force, it tested and worked out a pressurized cabin and motors equipped with a two-stage supercharger.
FW-191.
In the same period, the rival firm Messerschmitt AG proposed its previously “frozen” project of the Me-209N high-altitude interceptor, a further development of the Me-209 record aircraft. However, the developed machine did not confirm the expected results, so the development was finally discontinued.
Aircraft created under the Hohenjager 1 program were designated FW-190B, and the first prototype of this modification was the FW-190V12, which has a pressurized cabin and equipment for high-altitude flights. Soon three more modified FW-190A-3 / U7 aircraft were prepared for testing.
In parallel with the tests at the Focke-Wulf, BMW continued to fine-tune the prototype of the BMW 801TJ engine equipped with a turbocharger, which was planned for installation on the serial FW-190B. However, these engines, by order of the RLM, "Focke-Wulf" were never shipped on time promised earlier.
In the meantime, taking into account the test results of the first prototypes, three more serial FW-190A-1s were refurbished. These machines became the prototype FW-190B-O series. They had the following armament: two synchronous MG 17 machine guns and the same number of MG 151 / 20E cannons installed at the base of the wing.
The next FW-190B-O, like its predecessors, was a converted FW-190A-1 and was similar to the previous prototypes, with the exception of the BMW 801D-2 engine equipped with the GM system. This test vehicle was handed over to BMW.
Then three more vehicles were upgraded to the "B" series standard, which became the prototypes of the FW-190B-1. In the fall of 1943, the Focke-Wulf company decided to stop fine-tuning the FW-190B machines, directing all efforts to develop a new version of the FW-190C.
The failure in the execution of the Hohenjager 1 program, in the execution of which the FW-190B was developed, did not affect another of the same type of Hohenjager 2 program. The main difference between this program and the "Hohenjager 1" was the use of the DB 603 engine.
The development of a new prototype fighter, named FW-190C, was required not only due to the use of a new engine. The FW-190C with DB 603 was supposed to be equipped with a turbocharger developed jointly by DVL and Hirh. Daimler Benz sent several prototypes of the DB 603 to Focke-Wulf. Several production aircraft of the A-1 series were used to make the FW-190C prototypes.
A DB 603Aa motor with a centrifugal supercharger and a three-blade propeller was mounted on the FW-190V16. In August 1942, it was handed over to the Daimler Benz plant in Rechlin for comprehensive tests. Already in the first flight, a malfunction of the cooling system was identified. In the fall of 1942, after eliminating the defect in the cooling system, flights resumed, while in one of the sorties the pilot reached an altitude of 11,000 m.
Soon, at the Daimler Benz factory airfield, the FW-190C prototype reached a speed of 727 km / h at an altitude of 7000 m and reached a ceiling of 12000 m. Flying at the level of the practical ceiling became commonplace - the car sometimes stayed at this altitude for more than an hour and a half!
Naturally, in the conditions of real hostilities with installed weapons and the necessary fuel reserve, these indicators could not be achieved, however, in all respects they exceeded those with an aircraft with a BMW 801, even with the GM-1 system turned on.
In the late summer of 1944, as a result of a daytime air raid by Allied bombers on the Daimler Benz plant, the FW-190V16 was destroyed. FW-190C prototypes received DB 603 engines without turbochargers, and were, so to speak, intermediate or transitional machines from FW-190B to "C". But the FW-190V18 was the first aircraft - the standard of the FW-190C series. It was the first to be equipped with a DB 603G engine equipped with a turbocharger, but later, due to a shortage of these engines, it was equipped with a DB 603A-1 and a new four-blade propeller.
The FW-190V18 engine was equipped with a TK 9AC turbocharger (Hirth 9-228, developed jointly with DVL and Hirth 9-2281). The compressor had a mass of 240 kg (of which 60 kg fell on the gas turbine impeller) and had to 22000 rpm at a temperature of the incoming exhaust gas of 950 ° C. The device, clearly requiring further refinement, was installed under the fuselage, forming a kind of pocket, because of which the FW-190V18 was nicknamed "Kangaroo".
At the end of the winter of 1942, the test vehicle was handed over to Daimler Benz, at the factory airfield of which, after the new year, the vehicle was flown over. For further test flights, the chief pilot of the Focke-Wulf firm G. Zander was sent to the company, who, after nine flights, expressed his negative opinion about the new machine. Impressed by the flight, he qualified the aircraft as unfit for flight and expressed the need for a number of modifications to its design.
According to the chief pilot, the center of gravity of the car, due to the installation under the fuselage of a heavy compressor, moved back to the tail so much that the car did not want to rise above 7700 m. At any altitude, the aircraft is not stable in all planes and is difficult to control. The turbocharger did not produce even 20,000 rpm.
After the modification of the FW-190V18, several more prototypes of the FW-190C aircraft were prepared from the serial A-1. All these machines were equipped with a DB 603S-1 engine with a TK 11 turbocharger, had a pressurized cabin and a wing increased to 20.3 sq. m area. On them, the implementation of the "Hohenjager 2" program, which became the basis for the FW-190C, was completed. Despite the fact that the machines of this series could become successful high-altitude fighters, this did not happen. The reason - too slow "maturation" of the DB 603 engine, forcing TA RLM to recommend "Focke-Wulf" to suspend the development of the FW-190C.
At the end of the war, fascist Germany had serious problems with raw materials, primarily with certain types of alloying metals. Without them, it was impossible to produce high-quality turbines and other necessary parts of high-temperature turbochargers, the service life of which did not reach even 20 hours, and then burnout of the gas exhaust pipe housings occurred. German engineers were never able to put a reliable turbocharger into production until the very last days of the war.
The third high-rise project based on the FW-190 design with a Jumo 213 engine was the FW-190D. At the turn of the 40s, the engine department of Junkers Flyugzeug and Luftwaffe AG was working on a new 12-cylinder in-line 1750-horsepower liquid-cooled engine Jumo 213, designed by Dr. August Lichte.
The Jumo 213 was a further development of the Jumo 211, while it had smaller geometric dimensions and weight, and also worked at higher revs and developed more power. Allied bombers' strikes slowed down the development and preparation of serial production of this engine. Therefore, in the required quantities, it began to be produced only in the summer of 1944, while their monthly release was about 500 copies.
Initially, the engine was designed as a "bomber" engine, but Lichte envisaged the development of two modifications "C" and "E", adapted for mounting weapons in the collapse of cylinder blocks and, therefore, suitable for use on single-engine fighters. Interestingly, the Jumo 213 mounting points were completely identical to the mounting points of the DB 603 engine.
Kurt Tank, probably not without a strong recommendation from RLM, decided to use the new engine on the FW-190, according to an "urgent" plan to develop a high-altitude fighter based on production vehicles with maximum use of predecessor components.
The first prototype of the "D" series was the FW-190V-17, converted in the winter of 1941 from the serial FW-190A-0 fighter. The fighter fuselage has become noticeably longer. The nose of the car, in which the Jumo 213A engine was located, was extended by 60 cm. The forward mixing of the center of mass made it necessary to lengthen the tail section of the fuselage by 0.6 m. The compensation section between the central part of the fuselage and the empennage, unreasonable from the standpoint of the requirements of the laws of aerodynamics, was made in such a way that allowed to change the debugged airframe production technology to the least extent.
The next five vehicles were FW-190D-1 prototypes with a standard leaky cockpit, which was planned to replace all variants of the FW-190A fighter. The delivery plan assumed large-scale production of the D-1 version, equipped with a Jumo 213A up to 950 vehicles per month.
The D-1 version was not serially built, and its only copies were five prototypes. For the next version of the D-2, two experimental vehicles, the FW-190V26 and FW-190V27, were planned. Both aircraft were equipped with a pressurized cockpit and DB 603 engines. The armament consisted of a pair of synchronous MG 131 machine guns and an equal number of MG 151/20 cannons in the wing bases. Both prototypes were the only representatives of the FW-190D-2.
By the beginning of 1944, Focke-Wulf had introduced many changes to the design of its aircraft, which affected not only the high-altitude fighter created under the program, but also other FW-190 series. For example, rejection of the problematic cab sealing system. But the most important proposal was a new component standardization system, which influenced the entire production of the FW-190 fighters.
It was as a result of these actions that they decided to stop developing versions of D-1 and D-2. Instead, a variant of the future development of a fighter and the first production version of a high-altitude fighter was given the name FW-190D-9, since the fuselage of the machines of this version was similar to the fuselage of the FW-190A-9. In turn, variants D-3 - D-8 were not designed at all and, accordingly, were not manufactured.
The order for the initial fuselage layout of the projected FW-190B-9 was placed in October 1942, and Focke-Wulf began construction at the end of the year. The RLM commission made an official inspection of the presentation of the layout in the middle of the summer of 1943.
The launch of the FW-190D-9 was scheduled for mid-August 1944. The flight test results were encouraging, but the tests themselves lagged behind the established deadlines, since of the five prototypes, due to the bombing of Germany, three remained. Despite this, the start of production was met, and the first machines of this version were laid down at the Focke-Wulf production site in Cottbus and under a subcontract with Arado. In September, licensed production of the FW-190D-9 began at the Fieseler plant in Kassel.
Compliance with the deadlines for the start of production was made possible by the fact that in March, the design bureau, led by Rudolf Blaser, sent sets of technical documentation to the factories intended for the production of the FW-190D-9. The production vehicles differed slightly from the prototypes. So, to neutralize the reaction of the propeller, the tail unit was changed, increasing its area, in addition, the fuselage structure was strengthened. When assembling engines, engineers used a lot of new design solutions. For example, the FW-190D-9 has a round hood with an annular radiator, similar to that of the Ju-88 bomber. In addition, there was no oil cooler air intake on the hood, it was mounted in the collapse of the engine cylinders and it was cooled with liquid from the general system of the engine itself.
Some technical problems were solved in a rather original way. In order to reduce the cross-sectional area of the engine compartment, the designers had to move the oil tank, which rested against the engine mount and had a large volume. Then we decided to simply pass the strut of the engine mount through the oil tank! Getting acquainted with the captured FW-190D-9, aviation specialists were amazed at the originality of the solution.
The first production fighter, the FW-190D-9, was flown around in early autumn 1944. The vehicle was used in flight performance tests. In September, the failure of the supercharger led to the need to replace the entire power plant. The new Jumo 213С-1 was mounted on the car. Tests were interrupted a month after another engine failure and did not resume until early 1945.
In September, FW-190D-9 arrived in Hanover-Langenhagen from Rechlin. There, at the airfield of the company, the MW 50 system was installed on the aircraft, providing a short-term increase in the power of the Jumo 213A to 2100 hp at an altitude of 5000 m. Interestingly, it was originally forbidden to turn on this system during takeoff, but then this restriction was removed. The FW-190D-9 was handed over to the Junkers plant for air testing of the engine.
Interestingly, the D-9's initial impression on the German pilots was unimportant. It was planned that the Jumo 213 will have a power of up to 1850 hp, but in fact it was at 100 hp. below. At the same time, the pilots also noted that the new FW-190 turned out to be less maneuverable.
The pilots disliked the FW-190D-9 so much that K. Tank was forced to personally come to III / JG54 in Oldenburg to try to convince the Luftwaffe pilots of the merits of the Dora-9. However, his arguments were as follows: “The FW-190D-9 is a temporary measure until it goes into the Ta 152 series. The engine factories that make the BMW 801 were bombed. There are simply no other suitable air-cooled radial engines. The Reich has a significant number of Jumo 213s due to the fact that bomber production programs are "frozen."
The commander of the air unit R. Weiss said: "You say that this plane is a temporary measure … Well, if you want us to fly in the Dore-9, we will fly." To the surprise of the pilots, having adapted to the new fighter, they managed to find in it a sufficient number of advantages over such fighters as the FW-190A and Bf.109, including a higher dive speed and excellent climb rate.
In horizontal flight at an altitude of 6500 m, the FW-190D-9 accelerated to 685 km / h, and using an emergency engine mode with the MW 50 system turned on, the speed increased by another 15-20 km / h. Now Luftwaffe pilots could fly at speeds no worse than the American Mustang.
The continuation of the FW-190D series was a variant of the all-weather fighter with improved armor protection D-11, which differed from its predecessor by a more powerful Jumo 213F-1 engine with a turbocharger and MW 50 equipment. the difficult situation on the fronts and in the country was never started until the end of the war. The development of the next model in the "D" series proceeded in parallel with the design of the FW-190D-11.
In the fall of 1944, RLM began preparations for production of the FW-190D-12 with a Jumo 213F engine equipped with a supercharger and, in addition to it, the MW50 system. A prerequisite for the timely start of mass production of the FW-190D-12 was the launch of two-stage superchargers no later than November 1944.
The FW190D-12 series was a modification of an all-weather fighter, with reinforced armament from MG 151/20 cannons in the wing and a synchronous 30 mm MK108.
The prototypes of the next and last, equipped with Jumo 213 engines, the D-13 series were the V62 and V71 aircraft transformed from the FW-190A-8 serial fighters. Both of these machines actually did not differ from the representatives of the previous series, with the exception of the MG 151/20 synchronous cannon mounted instead of the 30 mm MK 108.
Later, these fighters were fitted with Jumo 213F-1 engines with a 9-821 ЗН compressor and MW 50 equipment. Due to the fact that the D-13 series machines were supposed to be used as high-altitude interceptors, the prototypes were equipped with pressurized cabins. The FW-190D-13 series was supposed to be launched from December 1944, even before the end of the tests, since it differed from the D-12 only in armament.
By the end of 1944, there was significant progress in the development of the DB 603 high-altitude engine, which was improved by the efforts of the Daimler Benz design bureau and was prepared for production. As you know, even before 1943, Kurt Tank began designing a new fighter under the code Ta-152, planning to use the FW-190D airframe with a DB 603 engine with a supercharger or with the latest version of this type of engine. Despite the lobbying of the topic by K. Tank, RLM, the ministry did not want to stop the established production - the design unification of the new FW-190 fighter was practically absent. Thus, it was required to modify the aircraft already in production into a transitional version of a new high-altitude fighter. Such an intermediate machine was the FW-190D-14.
Two prototypes were hastily prepared. The first prototype was equipped with a DB 603E engine with a takeoff power of 2100 hp. with an improved supercharger, which made it possible to raise the engine's altitude to 11000 m and with MW 50 equipment. The second prototype received a DB 603E with a takeoff power of 1800hp.
For the D-14 planned armament, consisting of a synchronous cannon MK 108 or MK 103 and two wing MG 151/20. After completion of assembly in the winter of 1944, both prototypes were transferred for testing to Daimler Benz in Echterdingen. During the tests, they reached an altitude of 11,700 m and a speed of 710 km / h.
The final phase of testing the prototypes of the D-14 series coincided with the final stage of the war, and therefore the serial production of the FW-190D-1 4 could not be realized.
There are other reasons why this series ended on two prototype machines. For example, simultaneously with the development of the D-14 series, work was underway on the D-15 variant, which was better adapted for mass production, or that RLM allowed the detailed design of the Ta-152 to begin. Therefore, after the cancellation of the program for the further development of the FW-190, both vehicles were transferred to the pressurized cabin test program for the Ta-152 project. In general, the D-14 series was initially stillborn.
Work on the latest model, the FW-190D, began at the same time as the FW-190D-14. The new version of the D-15 was based on the FW-190F-8 design, while the wing and other parts, with the exception of the front and tail parts, taken from the Ta-152C, remained unchanged. In other words, the FW-190D-15 was a mixture of the FW-190F-8 and Ta-152C designs, with a simpler design than even the FW-190D-9.
The start of the serial processing of the FW-190F-8 into the FW-190D-15 was planned from April 1945 to which, however, of course it did not come. Thus, prototypes of this version were not produced. However, from April 11 to April 17, 1945, at Gaspel's request, 15 FW-190Ds were transferred from combat units to replace the Jumo 213A-1 engines with DB 603G.
Since the plant in Echterdingen was the subject of constant Allied air raids, the refurbishment was carried out at another plant in Nellingen, located 50 km from the main plant of the company. They managed to replace engines only on a few machines, which made up an experimental batch of FW-190D-15. The non-converted planes left there on April 22, that is, at the time when Nellingen was occupied by American troops.
Two FW-190D-15s did manage to be transferred to combat units, one of which was found by American troops in very poor condition.
The Long-Nosed Focke-Wulf was the best production fighter in Germany. He showed himself perfectly in aerial battles with "Mustangs" and "flying fortresses". In total, more than 700 FW-190D fighters were produced out of a total of 20,000 FW-190s. But no fighters, even the most successful ones, were able to save the Reich. Nothing could stop the victorious offensive of the Soviet Army.
