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3. 2nd 2nd
After the epic with the He 100, Heinkel completely stopped work on a mass single-seat piston fighter. However, the property of the human mind is such that, finding the pleasure in thinking about a certain subject, it is useless to forbid this for oneself later. And Siegfried Günter had no intention of forbidding himself anything. The fact that the company actually turned back on the fighters did not mean that he too should get them out of head. Especially since unlike other members of the design team, he did not notice any dead end in the work on the "hundred". Well, let's say the "hundred" did not meet today's requirements. But, according to Siegfried, there was no such construction, which could not be given the necessary properties by means of directed changes, larger or lesser. And the fact that He 100, conceived already during the competition with Messerschmitt, when the fighters of the monoplane era were just only looking for their face, did not quite correspond already to their quickly determined appearance, he understood for a long time. And here also information began to come from overseas about a completely new turbochargered generation of fighters Curtiss, Bell, Lockheed and Seversky, which supposedly reached the ceiling, previously subject exclusively to special high-altitude aircraft, and had the maximum available for "hundred" speed already as a cruising, moreover, at higher altitudes. And, most importantly, some of them were quite heavy crafts that achieved high flight performance without prejudice to other combat properties.
And most importantly, Siegfried clearly understood the requirements put forward to the fighter by modern tactics of its use, and knew perfectly well how to meet these requirements with advanced design and technology. For a long time, he had in his head a set of information that summed up the appearance of the most perfect fighter at the moment. And when the information became too detailed and extensive for memory to manage, he began to write and sketch. But in real work, Siegfried could not to squeeze his ideas between the authoritative decisions of his older brother Walter, Heinrich Hertel and Heinkel himself. Siegfried was especially embarrassed after the failures with the elliptical wing that he once advocated. And only when the situation sometimes reached an impasse, he allowed himself to push colleagues to ideas, and even then so unobtrusively that it was difficult to convict him of authorship. This was the case with the radiator and forward sweep for the V11. And now, observing the deplorable situation in the company with his favorite fighters, in view of the fact that the senior colleagues' own attention to them has diminished, and also since he alone was now responsible for the Günter's mark, Siegfried cheered up, and on a joyful May day, especially conducive to a sincere conversation with the chief, laid out everything to Heinkel from the soul.
According to Siegfried, from the cardinal things only two simple changes needed to be done.
First, it was necessary to give the fighter the ability to carry a tangible combat load. Usually this meant an increase in the wing area, and as a result - an increase in drag, an increase in length, an increase in mass, an increase in strength, etc. etc. A large wing was also needed for altitude. Günter proposed to do without a significant share of all this, having received additional lifting force due to the carrying stabilizer.
Secondly, it was possible to achieve parity with the Americans only by similar installing a turbocharger. And here it was generally accepted to place boosting devices in the fuselage behind the engine, that required an air intake which protruded out of fuselage profile and gives additional resistance. Leaving the air intake like that of the "hundred" supercharger - in the leading edge of the wing - was also not optimal. Günter placed a turbocharger with a large frontal air intake in front of the engine in his "mental" fighter.
Typically the contours of the aircraft were drawn around some existing engine. One of Günter's main ideas was that in his design, on the contrary, the engine had to coincide with the contours of the aircraft so much that the crankcase cover turned out to be the outer surface of the aircraft. This led to a very small frontal area of the engine compartment.
Siegfried set out his plans so clearly, as if he were simply describing the finished aircraft already standing in front of them. With each question and each of his answers, it became more and more clear - this is exactly what the future fighter should be. Heinkel looked at the sketch and was amazed - for the first time he saw a drawing in which, it seemed, there was not a single constructive, in which every smallest detail, every line was of fundamental importance.
And Heinkel decided that they still had time. Immediately resurrected the sweet anticipation of the birth of a new craft, disputes to the hoarseness of the night without a break with Heinrich and Siegfried (miserably Walter is no longer with them) among the heap of daggled sketches. Anticipation, for which he could exchange everything that he achieved over the years - wealth, fame, position. In such a mood, Heinkel immediately rushed off with the sketch to Hertel. But he did not share the enthusiasm of the chief. Looking sideways in bewilderment at the drawing, he asked where Heinkel had gotten such nonsense, and then expressed doubt that such a cuttlefish would even be able to take off.
And it was necessary to act quickly so as not to lag behind Focke-Wulf and Messerschmitt. The next day, Siegfried Günter became the technical director of Heinkel AG. It was carte blanche for the embodiment of all his ideas, even the craziest ones.
So, the airframe for the new fighter in the project was almost ready. But there were two troubles regarding the key point of the whole case - the engine unit. One was that the required turbocharger was simply not available in Germany. The second trouble was that even the last of the Jumo 211, having neither power nor altitude reserve, could not realize the capabilities of such a turbocharger, even if it existed.
It was Heinkel's turn to have soul conversations. First, he called to him Dr. Seewalde, who was in charge of turbocharger work at the German Institute for Aeronautical Research. Just called, because the doctor's group collaborated with Hirth Motoren GmbH in the development of turbochargers. And after the death of Helmut Hirth on July 1, 1938, this firm actually passed into the hands of his friend, Ernst Heinkel. Who now became the owner of not just the company, but the Heinkel-Hirth AG concern. By the way, Heinkel, who read this name not otherwise as "Heinkel minus Hirth", was disgusted by it. He himself ordered to write Heinkel+Hirth in all documents. Thus, with the light hand of Heinkel, the H+H brand was born.
Heinkel promised the doctor all kinds of support and funding for his group in the DVL, and accepted the himself doctor on the staff, making him the head of turbochargers division at the Hirth company. Instead, the doctor should have to postpone experiments and focus on creating a specific model, at that it was to be created in the closest cooperation with the JuMO firm. In his "speech in response," the doctor complained about problems with the turbine, which must be both heat-resistant and durable. Heinkel said that next to the doctor there would be work a division that creates a turbine for much more severe strains and temperatures, and that he can use all the data of the work of this group, provided confidentiality is maintained, of course.
Then Heinkel met with Walter Kambeitz, the technical director of JuMO, with the intention of playing on a sense of pride, or on the competition with Daimler-Benz, or on all whatever comes to mind, but by hook or by crook to persuade him to closely cooperation of the work on the new engine Jumo 213 being created at this time. According to Heinkel's proposal, instead of its superchargers, JuMO was to use the Hirth-DVL booster system, which would free up forces to accelerate the development and release of the engine itself, and would also result in an engine more perfect than JuMO could get when using a driven supercharger. Heinkel begged to stop working on other piston engines for the sake of finishing Jumo 213 as soon as possible, convincing that tormenting himself with the rest was pointless, since they would soon be replaced by jet engines anyway. He even offered assistance with work on a jet engine.
The reaction of the Junkers Flügzeug und Motorenwerke AG management has boiled down to deign the experiment with a turbocharger. The possibility of cooperation was made dependent on the results of this experience.
Further events developed as follows. Hirth requested the turbocharger requirements and interface designs, and sent JuMO the expected performance. The declared pressure was 1.67 atm up to an altitude of 7500 m and 1 atm up to 9250 m.
The response was that the claimed performance seemed too optimistic, that it was impossible to base work on a real engine on dubious assumptions, and that a working prototype of a turbocharger was required to evaluate performance. Apparently, the Junkers management feared that engine incompleteness could cause failure, which would negatively affect the company's reputation. And it seems that they did not want to oblige itself with promises of a soon completion. Regarding the request, it was said that it is not yet possible to determine exactly what characteristics are required from the turbocharger, and the shape of the seats will depend on the design of the turbocharger. In general, to build a prototype of turbocharger, you first have to build a prototype of turbocharger...
Then Hirth requested an example of the engine to independently determination the required characteristics. From JuMO answered that there are few engines, that they all are in work, and each on account.
But Koppenberg did not take into account that he was dealing not with someone, but with Heinkel, seasoned in behind-the-scenes battles. The latter, after reading the last answer, sighed about the unlucky subcontractor and immediately, without getting up from his working chair, scribbled a petition in RLM stating that instead of producing light engines, the needs for which, in his opinion, were more than covered by the capabilities of, say, the same Argus, he wants to occupy the capacity of Hirth with releasing of "real" engines for the Luftwaffe. Moreover, the release of the JuMO engines, since only they, say, are desperately needed for his bombers. And with the release exactly of Jumo 213, since only with a new engine can its bombers make the Reich indestructible. And that Jumo 213 is not completed, so Hirth's experts will help - you look, and fine-tuning will go faster. As a result of this "initiative" over the summer, Hirth received not only a example of the engine, but all the documentation for the Jumo 213, as well as access to all further work on the engine.
And by the new year 1940, JuMO was "blessed" with a gift - Hirth returned the example. But this was already a slightly different "two-thirteenth".
Hirth did not only do her part of the work, but also fulfill what JuMO was supposed to do. And even overfulfill.
From the original engine only the cylinder block remained. The units, in fact, also generally remained the same. But Hirth made a new reduction gear housing, placing the units on it. All units were already driven by a reduction gear. Now the engine could be attached to the firewall directly by the rear end of the cylinder block. Thanks to this simple change, without taking into account the turbo/supercharger, it became 8% lighter and 15% shorter. It is also important that the heaviest cylinder block was now the rearmost part, as close as possible to the attachment points, and the attachment consoles themselves became shorter. This has a beneficial effect on vibration conditions.
The exhaust gases were fed forward, where they drive turbine. That rotated the two-stage axial compressor located in front. Further, the air through the intercooler on the lower surface of the motor unit would have to flow to the engine supercharger, which was also located on the main shaft, from which it was driven by planetary gear. However, a miscalculation showed that two low-speed compressor stages, in comparison with 20 thousand rpm of the turbocharger, will not only thresh the air, but even slow down the flow. Therefore, in the engines that went into series, it was necessary to abandon the mechanical drive of the supercharger, and put it on the compressor shaft, which, as a result, received two additional centrifugal stages. Now air entered the intercooler after passing through the centrifugal stages.
Thus, as was proposed, only the improvement of the engine itself, the cylinder block, remained to JuMO's share - mainly in terms of strength.
A takeoff power class of about 2000 hp at 3600 rpm and max altitude class of about 12,500 m was expected.
The engine unit turned out to be quite long and heavy, which further shifted the center of mass forward. In addition, the carrying stabilizer required a more rear centering. Therefore, although the wing was shifted forward and redesigned, straightening the break, again had to resort to the already tried solution - negative sweep.
For the wing and stabilizer, a profile with an even more rearward burble point than that of the He 100 was used. The almost symmetrical profile had insufficient carrying properties at low flight speeds and during takeoff, especially with increased load. Therefore, the engine was installed with a nose tilt downward by 4.5°. When the lift dropped at low speed, the plane was oriented along the thrust line, the wing lowered relative to the point of thrust application, and received a certain attack angle - the lift was retained. With an increase in speed, the lift increased, the wing rose relative to the point of thrust application, and the attack angle decreased to almost 0° at maximum speed - the minimum resistance was achieved. But even then, the slanted propeller was blowing a slightly upward flow on the wing, which created the effect of a positive attack angle. The total carrying surface area was 16.7 sq. m of wing plus 3.3 sq. m of stabilizer.
If everything was clear with the carrying surfaces, then with the fuselage there was some hitch. At first it was based on the "hundred" construction. But Günter, instead of sheathed frames, wanted to use the ultra-modern assembly technology from large-volume spatial elements in the new aircraft. And the shape of the tail section of the "hundred" did not really fit into the frame of this technology. In addition, it was necessary to ensure mating with the stabilizer located unusually low in order to withdraw it from the aerodynamic shadow over the entire range of attack angles. In search of a suitable shape, the models of several variants were blown, which did not satisfy Siegfried. Fortunately, Robert Lussier returned from Messerschmitt at that moment. He told Günter about the shape of the fuselage of the P.1065 project developed under his supervision, and an acceptable solution was born instantly.
The engine mounting brackets have become not only load-bearing elements and at the same time external surfaces - in addition, they have become tanks: one for oil, the other for coolant.
In general, large-sized stamped panels were widely used, which served as power and external ones. Two armored partitions were also power ones. The flanges of the partitions, which were also external surfaces, covered the ammunition and the pilot from the sides. The upper part of the rear bulkhead was supposed to protect the pilot when nose-over. These partitions, together with the side and bottom panels, formed a rigid sealed cockpit box, to which the engine mount consoles were attached in front, and these all made up the front part of the airframe. The cockpit was mounted on the front and rear longerons, connected to the tail section.
The landing gear was now attached directly to the front longeron. The tailwheel was non-retractable, controllable, part of the rudder design.
A wide-chord four-bladed screw was used. The tanks have been increased.
But that was not all. The gun of the future fighter was supposed to hit aircraft of similar mass and dimensions at a distance of 250 m - it was assumed that heavy twin-engine fighters with more powerful guns would fight with heavy bombers. Therefore, the barrel armament of the new fighter was made extremely small in number - just from one cannon. But what one!
MG FF, with which they suffered when installing on previous fighters, did not like for Gunter at all. He was impressed by its lightness and simplicity. He didn’t like the low-capacity uncomposable magazine and the insufficient rate of fire. Günter dreamed of cannon driven by an engine, which, according to his calculations, should have solved the issue of fire rate.
The arms group was actually only responsible for the installation of arms from other companies in the developed airplanes. However, the leader of the group, the talented designer Heinrich Straume, who came from Mauserwerke (What, however, Heinkel's talent for collecting equally talented subordinates! Almost the only talent needed by the boss.), had the idea of a gun, the barrel of which would be driven through a crank. Gunther suggested that he try to implement this idea.
Straume took the cartridge and the shape of the MG FF bore. The high rate of fire determined the high load on the barrel, as well as the high consumption of projectiles and the large required ammunition amount. Therefore, it conditioned the installation of a gun on a fighter only in the singular and the possibility of fire only in short bursts. But Günter and Straume considered all this not a disadvantage, but an advantage. The calculation was made on the fact that at the assumed huge speeds and angular displacements of aircraft relative to each other, the time to hold the target in the crosshair of the sight will be extremely short, and this will make a long burst unnecessary. But a high rate of fire will be critical, since it will provide a smaller gap between the projectiles of the burst, and, therefore, less deviation of subsequent projectiles in the burst due to aiming line displacement.
The thick barrel had longitudinal cooling ribs. The breechblock slid along the guide rails and this slides pair was designed as a linear roller bearing to reduce the strain. The feeding was tape. The links were connected by a cartridge, and the middle ring had a backlash, which allowed free bending of the tape, including in the plane. There was no bolt box. Fire control was carried out by a softened cam clutch in the drive. Ammunition had excellent access for reloading through the niches of the chassis. Feeding was carried out from two cartridge boxes of 500 rounds. If an overload on the external load was planned, only one box could be taken. Each fighter had to have two sets of ammunition boxes - while one was on the plane, the other had to be reloaded. Such an accelerated procedure was envisaged, since it was assumed that two pilots could be assigned to each aircraft.
The canopy was compact, but with good visibility. The rabbet of the cockpit canopy was sealed with a rubber gasket. To prevent the gasket from peeling off, the canopy did not slide, but swing back and up. In the event of an emergency escape, when removing from the locks, it was pushed in by a spring system and was thrown off by the oncoming stream.
The new craft in the firm documents was designated as "export fighter He 113F-0". But now the name He 113 was being used not to mislead the "world community", but to lull the RLM's vigilance and this time to really get rid of unnecessary attention and leadership interventions. The Ministry, having staged a farce with He 113, itself gave Heinkel this opportunity. Everything looked as if they were talking about a minor modification with the aim of selling abroad the aircraft not adopted for service. Therefore, the project, naturally, did not receive the "P" designation. The F mark was taken by analogy with the development of the Bf 109F, which was launched at that time, which, as it was known, was also supposed to become a cardinal modification of the "thin". And since, according to Heinkel, a cardinal modification was supposed to mean a dramatic improvement in performance, these two crafts seemed to him to be future competitors, so to speak, in the F generation. The V11 was considered the E model.
The craft first flew in January 1940, despite the fact that the engine had not yet been finished, and produced only 1500 hp. But Heikel needed this engine so much that he was ready to provide even precious first examples of a fighter for testing it. After all, the aircraft technology allowed it to be manufactured into the thousands. But the engine - the future of the aircraft depended on it. In fact, aircraft actually was this engine itself.
After the first successful tests, Heinkel did indeed send invitations to foreign missions to demonstrate the "new modification of the fighter". RLM was not notified of the show. But rumors about the craft had already spread, and the ministry sent representatives there - just for the sake of order.
The demonstration program did not contain any carcolom tricks, except for the appearance in front of the audience with a half-ton bomb mock-up, and a flight at a speed unprecedented for a serial aircraft after dropping this mock-up. The machine made a splash itself.
Heinkel responded to offers to immediately discuss the terms of the purchase, smiling that it was better to make deals in a calm atmosphere, when emotions and the roar of engines not interfere with this. In fact, he was expecting a completely different offer, for the sake of which he arranged this show, for the sake of which he went through all the circles - first with 112th, then with 100th, now with this one. And this proposal was finally followed.
Initially, it was ordered to submit the He 113 to the competition of "additional fighters" with the FW 190. But as got acquainted with Heinkel's brainchild, it became clear that no competition would work - the "weight categories" were too unequal. In fact, these were aircraft of different generations - Focke-Wulf, which had just reached a speed of 600 km/h and an altitude of 7.5 km, against Heinkel, who had overcome the "threshold of 720" and the bar of 12.5 km.
Moreover, the question arose about the expediency of further production even the main fighter - Bf 109. Even the last, F model, looked like an alien from the past in comparison with the He 113.
It would seem that there is nothing more to be desired. But the H+H specialists had new surprises in store.
4. Exzellenz among piston.
After the success of He 113F, RLM's preferences changed dramatically: now all the plans of the ministry and the Luftwaffe were guided by the level set by the activities of H+H.
Meanwhile, the success of the He 113F did not become a reason for Heinkel's team to rest on their laurels. In the process of creating the machine and engine, a number of proposals were made that were late for timely implementation. And now the specialists of H+H have taken up the modification of G, which must take them into account. RLM legalized these works with the stamp P.1076.
The power plant has undergone the greatest modification. During its creation, the consideration of interaction of the turbocharger with the drive supercharger showed that the mechanical connection allows the excess of the turbine power to be transferred to the main shaft. For this was decided to return the planetary gear, but now to the turbine shaft.
Another improvement was the increase of internal tanks.
The long blades of standard propellers were not designed for the high speeds the new motor was running at. Shorter high speed blades were created. On the latest modifications of the F model, there were five blades. And G model received coaxial propellers of opposite rotation with six even shorter blades each.
During the service of the gun, it became clear that the idea of short bursts at a high rate of fire was justified, and that such a mode of fire gives the usual ammunition consumption. To further dispersion reduce was decided to arm the new model with a two-barrel MG 155/2.
And that was not all that the H+H designers were able to squeeze out of the single-engine midsection.
G-1 data:
Dimensions: 9.6 m × 11 m
Carrying area: 16.7 sq. m + 3.3 sq. m
Weight:
empty: 3200 kg
takeoff:
nom: 4300 kg
max: 6000 kg
Specific load:
max: 336 kg/sq. m
nom: 240 kg/sq. m
Power: 2750 hp, with MW - 3000 hp
Max speed: over 800 km/h at 11 km
Climb rate: 25 m/s at 9 km
Ceiling: 14500 m
Internal fuel: 880 kg (1050 l) + 360 kg (400 l)
Aux tanks: 2 ×250 kg (2 ×300 l) + 960 kg (1200 l)
Max flight radius: over 2000 km
Max ferry range: over 4000 km
Barreled armament: MG 155/2 ×500-1000 cart
External load: up to 3 units (2 ×500 kg + 1000 kg or 1 ×2000 kg)
_________________
"I have thousand advisers who know how build a pyramid, but have not one who can tell me whether to build it or not." - John Kennedy.
Last edited by armyco on July 6th, 2021, 7:43 am, edited 3 times in total.
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