The sharp increase in maximum speed compared to the previous generation of machines, in particular the MiG-19, gave rise to a certain euphoria - both at the customer and at the MAP management. The support was at the highest level, since the interests of MAP also coincided (after all, he needed high rates for reporting), and the customer was the Air Force (who rightly wanted to have a new car in service, which would be a worthy response to the "American challenge" 100-series fighters). It should be noted that the rivals in the person of OKB-155, headed by A. I. Mikoyan, were not asleep: in the summer of 1955, before C-1, experienced E-4 came to the test, and at the beginning of 1956, and E- 5 with the standard engine P-11. In the spring, the 1956 machine literally kept pace with the stages of the factory test program, gradually increasing speed in the unspoken competition.
As a result, the game went on for some time, one can say honestly, and the first winner (they, as already mentioned, became the Sukhoi Design Bureau) was given the right to start the machine into mass production. Soon a government decree was issued, according to which C-1 under the designation Su-7 was launched in a small series at plant No. 126 in Komsomolsk-on-Amur. By the middle of 50, this plant, like many others, was the “fiefdom” of Mikoyan: MiG-17 was produced here and prepared for the production of MiG-19. But, in contrast to the “head” factories of MAPA, No. 21 (Bitter) and No. 153 (Novosibirsk), it was not, as it were, “native”: it was far away, and the production volumes were smaller, and the equipment was smaller ... And therefore that they were going to be “taken away”, the Mikoyanovites were fairly calm. Well, it was not necessary to choose sukhovtsy, and the set of working documentation was transferred to the serial production plant in a timely manner. In 1957, before the end of the tests, preproduction began there.
State joint tests of the Su-7 front-line fighter ended on December 28 of the year 1958. Su-7 had a thrust-weight ratio of about one and the load on the wing 290 kg / m2. The aircraft developed a maximum speed of 2170 km / h and had a ceiling of 19100 meters, which was the best indicator for domestic cars at that time. At the same time, during the course of military tests, a number of shortcomings, natural and inevitable for the head series, were revealed. They demanded immediate elimination, both in production and in the ranks. To this end, a team of factory specialists refined the onboard systems and the airframe in parts with complete disassembly of the equipment, the dissolution of the electrical hutches and their re-laying on new routes with thermal protection and soldering in the connectors. At the same time, an improved automatic control system ESWS-1В was introduced and replaced with a low-frequency unit on a wider one due to the replacement of the AL-7F engine with the AL-7F-1 with the new automation system. As already mentioned, the development in the series of MiG-15 and MiG-17 plant number XXUMX carried out after the leading related companies, using their technological development. But in the production of the Su-126 plant acted as an independent serial enterprise, fully providing design and technological development of the aircraft. Ultimately, the entire rush to launch into a series of still very raw machines came out sideways for the G7 - the initial release plan failed more than once due to the need for numerous modifications. In fact, in the 7, the 1959 of the Su-96 aircraft was manufactured.
Serial vehicles carried armament, consisting of two 30-mm NR-30 guns mounted in the root parts of the wing consoles with ammunition of 65 rounds per barrel (with an allowable cartridge sleeve capacity of 80 rounds). On the ventral beam holders BDZ-56F could be suspended two PTBs of 640 liters each or, in overload, aviation bombs up to 250 kg. Since most of the flights were carried out with PTB due to the gluttonous engine, in the series two more BDZ-56Ks were installed under the wing for bombs of caliber up to 250 kg or ORO-57K blocks with unguided rockets. Initially, ORO-57K were developed in OKB-155 A.I. Mikoyan for the MiG-19 fighter, but later found limited use on the Su-7. Each unit was equipped with eight 57-mm NARS S-5M with a high-explosive warhead. The projectile was detonated by a V-5M mechanical instant fuse. Aiming was carried out using an ASP-5NM aviation rifle scope, and to determine the range to air targets, the aircraft were equipped with a SRD-5M radio range finder mounted in a container of a retractable air intake cone. The Su-7 equipment included the RSIU-4 radio station, the ARK-54I Ilim radio compass, the MRP-56P Marker radio receiver, the SOD-57 and SRO-2 Chrom transponders, as well as the radiation warning station SPO-2 "Siren-2".
In the meantime, the competitors represented by OKB-155 A.I. Mikoyan increasingly "stepping on his heels." As already mentioned, they were the first to start the race for the best fighter - February 14 1955, test pilot OKB GK. Mosolov took to the air an experienced E-2 with a swept wing and an RD-9B engine with an afterburner 3250 kgf, previously installed on the MiG-19. It was a temporary solution, since the projected E-1 fighter was supposed to be equipped with the new AAA airfields. Mikulin AM-11 kgf afterburner 5110 and triangular wing - the latest "squeak" of the aviation fashion of those years. Due to the lack of E-2, they didn’t reach the set maximum speed in 1920 km / h and the 19000 ceiling m. The E-4 fighter variant with a delta wing and the same X-Rum 9 also didn’t “shine” with flight characteristics - its maximum the speed was only 1290 km / h, and the ceiling was 16400 m. Against this background, the results shown by Sukhov's C-1 looked more preferable. The E-5 triangle with a modified wing and the AM-11 TRDF (in the Р11-300 series) did not correct the situation either. The aircraft, because of the still insufficient engine power, did not reach the TTT Air Force and was then regarded by the customer as unsuccessful and unpromising. The serial production of the E-5, which received the designation MiG - 21 in the series, began at Tbilisi Aviation Plant No. XXUMX and was quickly rolled up. At the same time, there were practically no complaints about the complex of flight characteristics of the new Sukhovo machines. Air Force Marshal K.A. Vershinin 31 January 9 of the year in a letter to the Central Committee of the CPSU pointed out that "the Air Force as a customer is interested in fine-tuning a large number of experienced aircraft in order to be able to choose ... In terms of flight characteristics, the Su-1958 has an advantage over the MiG-7 on the 21-150 km / h and the ceiling is 200-1 km, while it may be, after making small changes, a fighter-bomber. The Su-1,5 predisposition is more encouraging than the MiG-7. "
It seemed the fate of the MiG-21 hung in the balance, but the next day K.A. Vershinin together with the chairman of the GKAT P.V. Dementyev sends another letter to the same address, but already with a request to release the 10-15 MiG-21 from the existing reserve. Understanding the secrets of the “Madrid Court” is very difficult. The last request remained unheeded. However, someone “rescued” MiG-21; It is quite possible that OKB-300, which came to the rescue in time with the proposal on the forced version of the Р11F-300 engine, also said its word.
24 July 1958 of the year issued a decree of the Council of Ministers No. 831-398 and nine days later - GKAT order No. 304 on the construction of the MiG-21F aircraft (Е-6, product "72" of plant No. 21) with the Р11Ф-300 engine based on MiG-21. The new Р11Ф-300, the release of which began in 1958, had an afterburner thrust of 6120 kgf, acceptable reliability and allowed to significantly improve almost all flight characteristics of the fighter. 20 May 1958 year V.A. Nefedov tore off the ground E6-1, the first prototype of the fighter, later received the designation MiG-21F. With a forced TRDF, a sharp leading edge of the OT, a two-jump cone and other improvements, the MiG-21F developed the maximum speed of 2100 km / h, reached an altitude of 20700 m and had a flight range with one PTB 1800 km. His armament consisted of two 30-mm guns HP-30 (the same as on the Su-7), NARS, bombs and incendiary tanks. The machine had good stability and control, could be quickly mastered by pilots of combat units. In addition, with almost equal flight characteristics with the Su-7, it was simpler and easier (6850 kg versus 9245 kg). The MiG-21F was better suited for the Air Force FA because it had better flight and maneuverability, lower landing speed and, therefore, required airfields with less long runway (the length of the MiG-21F run was equal to 900 m, and the Su-7 - 1350 m). The Р11Ф-300 engine turned out to be less susceptible to surge, the Achilles' heel of the "seven", and the use of the forward-looking triangular wing added more points to the OKB-155 fighter.
Meanwhile, the continuing problems with the AL-7F on the background of a new competitor did not add supporters to a dry-car machine. It is abundantly clear from the tables below that Sukhoi has a large fighter. Nevertheless, comparing the aircraft of his and Mikoyan, it is clear that the Su-7 maneuverability characteristics turned out to be quite good. There is a significant advantage of the Su-7 in the turn radius, which is maintained with increasing height. But there is a slight lag in climb rate. The Air Force command was satisfied with the new P.O. Dry. However, the military also supported the alternative project of Mikoyan, who was better suited as a front-line fighter. Naturally, the problems arose with the MiG-21, but the number of these aircraft in the parts of the Air Force grew. In 1959, the aircraft was launched into a series at the Gorky Aviation Plant No. XXUMX, launching the launch of one of the most popular and famous jet fighters of "all times and peoples." And by the beginning of 21, the plants had already built more than 1960 (!) Machines. The concept of a light front-line fighter for air combat won out. The MiG-200 was distinguished by a simpler-to-use powerplant, lower fuel consumption, was less noticeable in the air, had better take-off and landing characteristics, and its adoption did not require an increase in runways throughout the country, which ultimately predetermined the choice of military .
In contrast to the success of the MiG-21F in the OKB-51 based on the experienced C-41, which reached the test speed 2230 km / h and the ceiling 19500 meters, the project of the C-21 fighter was developed. But before the construction of the prototype it never came.
Well, how was the situation in the United States, with constant attention to which military customers issued the TT?
In the US, Johnson with his F-104 deviated strongly from the initial plans and instead of a light fighter he created a manned rocket to achieve record-breaking performance. In general, overseas rival was the most unfortunate fighter. Actually, all this determined the future of the projects. The Americans took the non-maneuverable F-104A into service with the air defense units (and at the same time pushed it against the common sense to the allies as the main one), the MiG-21 became the “workhorse” of front-line aviation, and Su-7, in their letter, began to remake in a bomber. The latest “clean” Su-7 12 series left the assembly hall in December 1960. Total built 133 fighter, of which 10 pre-production and the first 20 production aircraft had engines AP-7F. Given the huge need of the Air Force for such fighters, the number of built Su-7 is just scanty - they were armed only with two fighter regiments - 523 and 821. Both parts were based in Primorsky Krai, closer to the manufacturer. Part of the aircraft entered the Yeisk Air Force Academy, where pilot training was deployed. Officially, the Su-7 was never adopted.
Today, from the height of past years, one can critically review the results of the work of that time. I remember in 1960-ies in aviation there was a saying: “The designer is Dry, the plane is raw, and the technician is wet,” but we will try to keep from the hasty and light-weight conclusions. It would be possible to refer to the “objective” factors that made it difficult for designers to choose the overall layout and parameters of the new machine. Such, for example, as clearly overestimated requirements of the customer and his lack of a clear concept of using the aircraft, and the OKB team has no practical experience in creating supersonic machines. Already in the process of construction and testing, the situation became much more complicated due to the non-fulfillment of tasks by subcontractors (primarily engines), the weighting of the equipment and the reduction of its characteristics. But all this is everyday life and routine, since the buyer is not interested in the seller’s complexity, the quality of the product is important to him, and any design bureau can make such excuses.
All this, of course, does not remove responsibility from designers for errors made when designing the aircraft, but here we still need to distinguish errors, so to speak, “conceptual”, related to the general level of aviation science and ideas about the subject of design. Such claims can be attributed, perhaps, to the entire generation of aircraft, both Soviet and foreign. Much more interesting for us is the question - who and how solved these problems? As an example, we can testify that in terms of airframe design, the Su-7 was an exceptionally reliable machine. According to the statistics of flight accidents, for all the time of its operation in the USSR Air Force there was not a single case of aircraft destruction in the air due to insufficient strength. And this is despite the fact that at the time of the design of the machine, the designers were virtually unknown to the rate of repeatability of loads for this type of aircraft.
The number of serious “conceptual” errors can be attributed to the relative imperfection of the aerodynamic layout (frontal air intake, and, consequently, large losses of internal volumes due to the long air channel; weak wing mechanization, and, as a result, deterioration of take-off and landing characteristics and d.) These reproaches would be quite fair, since they have practically nothing to argue with, except for the already mentioned references to the lack of practical experience of designers in the development of such machines and the firm, prescriptive nature of TsAGI's recommendations on choosing the layout - only from those tested and worked out at the institute.
Of particular note is the underestimation of the takeoff and landing mechanization. This mistake, which led to high take-off and landing speeds, was the “Achilles heel” of all second-generation cars, both Soviet and American. As a result, we had to struggle hard to improve them, but we failed to solve the problem fundamentally. Another example is the adjustment of the air intake to ensure stable joint operation of the turbofan engines with an axial compressor and inlet device. Here, the OKB learned from its mistakes, much then not realizing it because of ignorance of the subject, and already during the tests it found acceptable solutions to the problems. Similar difficulties arose before the OKB-155 when testing the machines of the “E” series.
More interesting is the question of choosing the engine. Was there an alternative to AL-7F? As is known, Mikoyan, who created the car of a lower dimension, took the P-11F-300 as a power plant. And I didn’t lose it, because, despite the somewhat delayed start-up period, over time, this engine reached the set parameters (except for weight), and in terms of reliability and resource, it was far ahead of its rival. How it all reminds history from front-line bombers ... Of course, from the standpoint of today it is easy to condemn P. O. Sukhoi for his choice of AL-7F, but is this justified? Indeed, at that time, when the choice was still to be made, everything was not so obvious. To ensure the specified characteristics, instead of one AL-7, we would have to deliver two P-11, and this made the machine more difficult and heavy.
The bet made by P. O. Sukhy on the AL-7F with high traction characteristics was justified in creating the high-altitude fighter, which the aircraft originally intended. In this capacity, he would probably be in no way inferior to the T-3 interceptor created in parallel with him.
If, however, to fantasize in the style of an alternative story, then it is clear that the Su-7, due to its higher cost and higher requirements for the runway, could not have become as widespread as the MiG-21. At the same time, a larger midsection of the fuselage, in case of rearrangement of the nose section by the Su-11 type of interceptor, could ensure the placement of a more powerful radar. From 1973, the Su-7 fighter would most likely get a P-23 rocket and be able to fight at medium distances. From the same year, the Su-7 could be equipped with the Р29-300 engine, which would allow raising the flight range to 1500 km without outboard tanks. With outboard tanks it would be possible to get quite a decent range. But the release of the updated Su-7 in these years would no longer make sense: with the same engine and in the same dimension, the more progressive MiG-23 was preparing for the series. I think that Su-21 could not become a long-liver, similar to MiG-7.
What performance could show the Su-7 in the Vietnam conflict is difficult to predict. In the near maneuver battle, he was not inferior to the MiG-21. However, large sizes would allow F-4 pilots to detect it more often and earlier than the small MiG-21. In part, this could be compensated by a more powerful on-board radar, which is mentioned above. In addition, a more powerful engine gave a more powerful heat trace. It would be much more difficult to drop the missiles from the Su-7 pilot's IC GOS from the tail than its counterpart on the MiG-21. Analyzing the fight with "Mirage" is even more difficult. If Mirages were migrating to horizontal turns, then Su-7 had an advantage here, but still it’s difficult for me personally to imagine Sukhoi’s best performance. In any case, the management did the right thing, giving preference to this competition MiG-21
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