The J-8 fighter is an enlarged design based on the J-7 fighter. Equipped with two WP-7A engines, the nose is lengthened to improve the high-altitude combat capability. This aircraft is a high-altitude high-speed fighter developed and produced by China Shenyang Aircraft Research Institute and Shenyang Aircraft Manufacturing Company in 1970s. It belongs to the second generation fighter, also known as the last second generation fighter in the world.
J -8 basic model, equipped with two turbojet -7A aero engines produced by Shenyang Liming Aero Engine Group Co., Ltd., with a maximum Mach number of 2.2. The machine is equipped with a 23 mm double-barrel gun, and the whole machine has 7 external points; Thunderbolt -2, Thunderbolt -5, Thunderbolt -8 short-range air-to-air missiles, Thunderbolt-1/medium-range radar-guided air-to-air missiles, unmanned navigation bombs and rockets can be used. In the1950s, the atmosphere in the Taiwan Province Strait was very tense. Taiwan Province Province sent U-2 and unmanned reconnaissance planes to express condolences to the mainland, and the US military often sent high-altitude reconnaissance planes to invade China's airspace, especially over the nuclear and rocket test bases, to obtain military information. However, the PLA fighters have limited high-altitude performance, so it is difficult to shoot down enemy high-altitude reconnaissance planes. In order to cope with this situation, in 1958, China started the independent design of Dongfeng 107 fighter and Dongfeng13 high-speed fighter. Both of these planes later suffered the fate of dying halfway.
Dongfeng 107 is a supersonic all-weather fighter designed by Shenyang Aircraft Design Institute. Its design indicators are: the maximum speed 1.8 times the speed of sound, and the ceiling is 20,000 meters; Install two engines. The aircraft was designed from August 1958, put into trial production in May/959, and made major modifications to the original design in June. The development stopped in October 16543813, and concentrated on developing Dongfeng 1 13 aircraft. Dongfeng 1 13 is a high-altitude high-speed fighter designed by the Academy of Military Engineering. The design index is: the maximum speed is 2.5 times the speed of sound, and the ceiling is 25,000m. The machine was designed at the end of 1958, and some parts were manufactured at 1960. Because the design index is too high, the materials, finished products, weapons and engines are newly developed, lacking inheritance, and divorced from the industrial level of China and the reality of aviation industry at that time. The design speed of aircraft requires a "thermal barrier", but in the 1950s, China did not solve the problems of aerodynamic heat and thermal stress theoretically and experimentally, nor did it establish the necessary aviation scientific research and experimental means. China does not have the technical basis and material conditions to develop this high-index fighter. Therefore, research and development had to be suspended at 196 1.
The aviation industry began to look for the crux of the problem through the failure of the development of high-index fighters: the foundation of independent design is not firm. Mainly reflected in two aspects: "First, professional supporting scientific research and design institutions and scientific research and experimental conditions have not yet been established;" Second, the design team itself lacks sufficient experience and necessary design reserves. "In order to solve these two problems, 196 1 established the Aviation Research Institute on the basis of the construction of the supersonic wind tunnel and flight research institute in the late 1950s, and set up a number of professional design institutes one after another, specializing in the design and research of aircraft, engines, instruments, electrical appliances, accessories and weapons. Some scientific research institutions have also been established to engage in applied research in aerodynamics, structural strength, lifesaving, optics and machinery, and automatic control. Among them, Shenyang Aircraft Design and Research Institute has concentrated domestic technical forces engaged in all aspects of aircraft design, and set up 13 design room, three laboratories and 1 general, aerodynamic and strength experimental factory, which has made organizational and technical preparations for designing fighters by itself.
At the same time, pay close attention to the improvement of the technical quality of the design team. Starting from 196 1, aircraft designers and technicians were organized to have a systematic "technical understanding" of the former Soviet MIG -2 1 aircraft. 1962 in may, the aviation research institute and the aviation industry bureau jointly issued instructions to make arrangements for understanding MIG -2 1 aircraft. Tang, president of Aviation Research Institute, visited Shenyang Aircraft Design Institute for many times to explain the meaning of "technical understanding", and mobilized scientific research and design personnel to carry out their work in a down-to-earth manner, laying a solid foundation for designing advanced fighters for themselves.
The step of "technical understanding" is to find out the main production technical problems, including technical keys and materials, according to the needs of imitation; Secondly, the combination of imitation, through the necessary experimental research, to understand its design ideas, design methods and technical characteristics.
During the "technical exploration" of MIG -2 1 aircraft, Shenyang Aircraft Design and Research Institute has completed 39 projects, including the verification of aircraft strength calculation report, the calculation of nose cone strength, the calculation of wing strength and stiffness, the analysis of aircraft combat performance and the verification calculation of aerodynamic characteristics. 27 items of 3300 high and low speed blowing tests were carried out; 64 tests, such as air inlet, aircraft vibration, seat ground ejection and flight, were arranged. Through these calculations and experiments, on the one hand, the design technical data are supplemented and checked, and at the same time, the original design methods are studied and mastered, and experience is accumulated. At the same time, the aircraft in western countries are also analyzed and studied. Shenyang Aircraft Design and Research Institute has systematically analyzed and studied five kinds of fighters and high-altitude reconnaissance planes, put forward research reports, drawn some drawings, and collected some technologies for reference. Practice has proved that it is correct to make the decision of "technical type penetration" for MIG -2 1 aircraft in three years. After several years of careful preparation and repeated brewing, the aviation industry has begun to develop new high-altitude high-speed fighters. 1in may, 1964, the institute of aeronautics and astronautics proposed to design fighters with better performance based on MIG -2 1. In June 5438+10, the new fighter began to demonstrate its scheme. At the demonstration meeting, Shenyang Aircraft Design and Research Institute put forward two schemes: single engine and double engine. The former is a newly developed large thrust engine scheme, and the latter is a modified trial-production scheme using a mature engine (turbojet 7A). Under the auspices of Tang, president of the Aviation Research Institute, the meeting decided to adopt the scheme of two engines. This correct choice is safe and reliable, and has a certain technical foundation, which is the prerequisite for the successful development of the J-8 aircraft.
1May, 965 17, Chief of General Staff Luo Ruiqing approved the tactical and technical indicators and development tasks of the new fighter. This plane was named J-8. Shenyang Aircraft Factory 1965 began to prepare for the trial production of the J-8 aircraft in the second half of the year. National leaders are very concerned about the development of the J-8 aircraft. 1965 in August 65438+April, when Vice Premier He Long listened to the report on the development of the J-8 in Shenyang, he instructed: "The J-8 should be produced as soon as possible." On August 18, 2008, in a letter to Zhang Aiping, Deputy Chief of Staff, Marshal Nie expounded several problems that must be considered in the design of the new aircraft, which played an important guiding role in the development of the J-8 aircraft.
Under the leadership of Gao Fangqi, the first deputy director and chief engineer, Luo Shida, the deputy chief craftsman, presided over the formulation of the 歼 8 process plan. This master plan was formulated on the basis of integrating the advanced experience of the former Soviet Union and Britain. This scheme adopts a new process matching method, that is, based on the mold line of gelatin plate, using optical instruments, fixture assembly machine and marking drill floor. Coordination method of combining local gauge setting with local mold and tire. Later practice shows that the whole machine has more than 1 1400 parts. More than 1200 standard parts, from more than 100 assembly to front and rear fuselage docking, fuselage wing docking, and then to the installation of engine and fuel tank on the plane, are basically successful. The new method also greatly reduces the process equipment and speeds up the trial production progress of the J-8 aircraft.
Just as the development was progressing smoothly, Gao Fangqi died on June 29th. 1966. The Ministry of Aviation Industry sent Liu Hongzhi, director of Shenyang Aircraft Design and Research Institute, to Shenyang Aircraft Factory as the first deputy director and chief engineer to fully lead the on-site design and trial production of J-8 aircraft. 1966165438+10. In October, Liu Hongzhi was forced to stop work due to the "Cultural Revolution", and the factory and the institute jointly established the J-8 R&D headquarters, with Wang Xin, the deputy director, being responsible for the overall organization and leadership. From 65438 to 0967, during the "Cultural Revolution", the vast number of scientific and technological personnel and workers went to work as usual, and the development of the J-8 did not stop.
Its main development work is undertaken by Shenyang Aircraft Design Institute and Shenyang Aircraft Factory. The development plan of the J-8 aircraft highlights the performance of high altitude, high speed, extended range, improved climb rate and enhanced firepower. In view of the shortcomings of the J-7 aircraft, it has been improved item by item, and all performance indexes have been improved: First, the maximum speed is 2.2 Mach number; Second, the maximum ceiling is more than 20,000 meters; Third, the maximum climb rate is 200 meters per second; Fourth, the basic range is 1 1,500 kilometers, and the maximum range is 2,000 kilometers; Fifth, the air combat time at an altitude of 1.9 million meters is stipulated; Sixth, install improved design aircraft guns and air-to-air missiles; The seventh is to install a radar with a large search distance. The J-8 aircraft adopts the aerodynamic layout form of nose intake, large sweep angle, small aspect ratio, thin delta wing, flat tail and double ventral fins. Two turbojet 7A engines are selected, and the thrust-to-weight ratio of the aircraft is 0.89, which is superior to that of the J-7 aircraft.
1September 1965, the design of the J-8 aircraft was in full swing. After the chief designer Huang died in a plane crash abroad in May, the technical work of the new machine development was led by Ye and organized by the chief designer's office headed by Wang Nanshou. In the same year, the wooden prototype of the J-8 aircraft passed the examination in February, 65438, and in March, 65438, 0966, the designer went to the factory to design with workers and technicians. 1966 produced a complete set of aircraft drawings at the end, and 1967 produced corresponding production documents at the beginning, and the factory immediately started trial production.
In the field design, more than 570 designers such as Wang Fushou, more than 80 workers with rich practical experience such as Chen Ayu and Wang Ahui, and more than 30 technicians implemented the "three combinations" to discuss the design scheme and design drawings together. During this period, technicians and workers in the factory put forward more than 2,330 suggestions for improvement, and 1660 suggestions were adopted, including 40 major improvements, which further improved the production technology of aircraft. For example, the innovative scheme of canceling the cushion block on the wing main beam is realized by using MIG-265,438+0 main beam with the help of technicians and workers. This transformation changed the traditional structure of MIG aircraft and reduced its weight by 4 kilograms.
In the process of aircraft development, designers have broken through many technical keys. In terms of aircraft aerodynamic layout, the biggest problem in designing supersonic fighters in the world at that time was to ensure the directional stability of the aircraft at Mach number. Gu Songfen, deputy chief designer, presided over the design research, and Ge Wenyong, an excellent pilot sent by the Air Force, cooperated to measure the directional stability and flying quality of the J-7 aircraft at Mach number, which provided reference and basis for the design of the J-8 aircraft. A research team composed of technicians from 60/KLOC-0 Institute, Shenyang Aircraft Factory, Aerodynamics Research and Test Department, Beihang University and Professor Xu made a lot of wind tunnel tests and research and analysis, and finally determined the design scheme of the vertical tail and ventral fin of the J-8 aircraft, ensuring good directional stability at Mach number.
Wing flutter of supersonic aircraft is the most dangerous aeroelastic phenomenon, and it is also an important factor restricting the maximum speed of aircraft. Guan De presided over the aeroelastic design of the J-8 aircraft, established a set of unsteady aerodynamic and flutter calculation programs, and made a large number of wind tunnel tests, ground vibration tests and real aircraft flight tests, and comprehensively determined the flutter characteristics of the aircraft. After adopting the above scheme, it not only ensures the aircraft to achieve the predetermined performance, but also minimizes the structural weight, thus improving the thrust-to-weight ratio of the aircraft. In addition, presiding over aircraft strength calculation and aircraft structure design has also achieved good results.
In the improved design of the engine, the technical research of hollow blades has made a major breakthrough. In order to increase the thrust of the engine, the temperature in front of the turbine must be increased by about 100℃, and the turbine blades can't bear such a high temperature. 1964, Ke Rong, deputy director and casting expert of 62 1 Institute, proposed to adopt air-cooled hollow blades. At that time, this technology had just developed abroad and was in a highly confidential state. Ke Rong cooperated with Shenyang Metal Research Institute, 606 Research Institute and Shenyang Engine Factory to tackle key problems. Under the auspices of Shi Changxu, Shenyang Metal Research Institute organized technical research to overcome the technical difficulties of blade casting. The first is the core choice. Small holes with different thicknesses should be evenly discharged on the blade with a length close to 100 mm, and the smallest aperture is only 0.8 mm After research and experiments by scientific and technical personnel, a usable mold was finally made, and technical problems such as coring and ultrasonic wall thickness measurement were solved one after another. 1966 developed the first cast porous air-cooled nickel-based superalloy blade in China, which was completely successful after being installed in an engine, thus narrowing the gap between China and the United States in this respect and becoming the second country in the world to adopt cast hollow blades in aero-engines.
The ammunition supply and discharge system of the J-8 aircraft gun is a design difficulty. It must ensure that the cannon can be fired continuously in the air. Previously, experts in the former Soviet Union thought that the design of this system was their patent and kept it secret. In tackling key technical problems, designers and workers did experiments together, refitted an aerial gun that can simulate shooting, and fired 10,000 fake bombs. Finally, the law was clarified and the design was successful. 1July, 968, the first batch of two 歼 8 aircraft completed the final assembly. 1July 5, 969, the first test flight of the J-8 aircraft. At 9: 30 in the morning, Cao Lihuai, commander-in-chief of the test flight site and deputy commander of the Air Force, ordered the release. Pilot Yin Yuhuan flew the J-8 plane over the airport twice and landed safely. From the scheme demonstration to the first flight, the J-8 aircraft experienced four years, including general layout, technical design, wooden prototype evaluation, drawing distribution, new machine manufacturing and testing, 10 month.
1968 September 15, 02 J-8 aircraft were tested for static failure. When loaded to 92% design load, the middle fuselage broke in many places, and the test results were unqualified. In the face of setbacks, the vast number of technicians are not discouraged and continue to tackle key problems. By June 1968, the weak parts of the structure were strengthened and various technical problems were verified and clarified.
1969 At 9: 00 am on July 5, 1969, at the airport of Shenyang Aircraft Factory, test pilot Wang Huan made his first test flight, flying at an altitude of 3,000 meters and a speed of 500 kilometers per hour, which was a complete success.
Since then, the J-8 aircraft has continued to fly in Yanliang Flight Test Institute, with Lu Mingdong as a test pilot. In the continued test flight, the plane encountered a transonic buffeting fault and could not exceed the speed of sound for a long time. Designers repeatedly tackle key problems and adopt various methods, and finally completely eliminate the transonic buffeting fault of 1977. Then, the J-8 aircraft solved major technical problems such as engine parking in the air.
1979 65438+February 3 1, the aviation product design committee agreed to finalize the design of the J-8 aircraft. 1980 On March 2nd, the National Military Standardization Committee approved the standardization. The length of the J-8 aircraft (with pitot tube) is 21.52m, the wingspan is 9.344m, the aircraft height is 5.4m, the service ceiling is 20,500m, the operational radius is 800km, and the maximum endurance time is 2: 35.
It took 10 years for the J-8 aircraft to fly from the first flight to the design finalization. Its development process is a process of "introduction, digestion and re-innovation", which indicates that China's aviation industry has embarked on the road of independent design from imitation.
Reasons for the successful development of J-8:
1, slowly but surely, from a practical point of view, the design of the J-8 is based on the "technical understanding" of MiG -2 1 aircraft for three years and drawing lessons from foreign aircraft technology. The choice of design scheme not only embodies the advanced nature, but also inherits it, which basically adapts to the domestic industrial level and technical conditions.
2. The technical decision is correct, especially the selection of engine, air intake mode and ejection lifesaving mode are fully demonstrated. The turbojet 7A engine used in the J-8 was changed to a high-temperature turbine on the basis of the original turbojet 7, and the first batch of engines were trial-produced in 1968 with the joint efforts of the research institute of the Ministry of Aviation Industry, China Academy of Sciences and relevant units of the Ministry of Metallurgy, which ensured the smooth production of the whole machine.
3. Mobilize all positive factors and bring collective wisdom into play. In the trial-production process, the combination of "scientific research, production and use" and "leading cadres, workers and technicians" was carried out to jointly develop the J-8, which quickly and well solved various technical problems in the development. Effective organization and leadership. The Ministry of Aviation Industry organized the whole industry to give a green light to the development of J-8 aircraft. All departments and regions in China have made great efforts to cooperate. The relevant departments set up a test flight leading group, the Ministry of Aviation Industry and the Aviation Research Institute set up a joint headquarters, and the Shenyang Aircraft Factory and the Aircraft Design and Research Institute jointly set up a field headquarters to conduct in-depth on-site command, and organized and solved 23 technical keys that affected the first flight. Cao Lihuai, deputy commander of the Air Force, made decisive decisions and played an important role in presiding over the test flight of the J-8 aircraft.
After the 1970s, the design ideas of fighter planes all over the world have changed. Instead of pursuing "higher and faster", they focus on improving the maneuverability of aircraft at low and medium altitudes and improving airborne electronic equipment, weapons and fire control systems. In order to adapt to this trend and meet the new requirements of military equipment, Shen Fei Company developed the J-8Ⅱ aircraft on the basis of J-88. In June 1984, the first flight of the prototype was successful. On March 8, 1988, the design 歼 8Ⅱ was finalized. In the same year, 10, 15, the Military Design Committee officially approved the design of the J-8Ⅱ aircraft.
J-8 is a high-altitude high-speed fighter developed and produced by China Shenyang Aircraft Research Institute and Shenyang Aircraft Manufacturing Company in 1970s. It belongs to the second generation fighter, also known as the last second generation fighter in the world. ○ 8 daytime type, all-day type and○ 8 Ⅱ have been successfully developed. Especially, on the basis of the J-8 daytime plane, the J-8ⅱ plane suitable for national air defense operations has been developed, and now it has become the main battle type of national air defense in China.
There has also been a great breakthrough in the airframe materials of 歼 8Ⅱ, which is the first time that China has used composite materials on its fighter plane in a large area.
In addition, on the basis of the J -8II, Shen Fei has successively developed improved J -8IIM, J -8III, J -8D, J -8F and J -8T.
歼-8Ⅱ develops key weapon systems, fire control systems, airborne electronic equipment and power plants. In order to provide space for the large-aperture radar antenna, air intake is adopted from both sides, which is also the biggest appearance difference between the aircraft and the J-8. This improvement leaves a lot of room for the future improvement of 歼 8Ⅱ fire control system. Finally, the radar adopts 208 monopulse fire control radar. The 208 radar is developed on the basis of the 204 radar used in the J-8. It is the first radar with interception capability in China. Using monopulse system, the plane search distance is 40 kilometers, and equipped with continuous wave illuminator, it can theoretically guide radar-guided air-to-air missiles launched beyond the line of sight.
208 radar is specially developed and produced by 780 factory. The General Staff Department put forward the development task in 198O, at that time, it was clearly pointed out that the domestic 204 radar could be selected for improvement, in order to make the J-8II have certain interception capability. 1981July 2 1 day, Air Force Command and other units reported the tactical and technical requirements of the 204 radar reform. In September, the validation meeting of the 204 radar transformation scheme was held in Beijing, and then the 204 radar was renamed as the 208 radar. At the end of the year, 780 Factory signed the first batch of agreements with 60 1 Factory and12 Factory to develop five 208 radars, submitted two finished products and started the development of 208 radars. The superior stressed that, in particular, great efforts should be made to improve the range of radar, reduce the use height and improve reliability and maintainability.
1June 1984, due to the lack of more than 60 parts and materials, 175 parts could not be delivered within the contract period, and it was difficult to complete scientific research and finalize the prototype of the flight test radar as planned. During the period of 1985, Zhengzhou Air Force 19 Division conducted a scientific flight test of 208 radar, and found that the interception rate was low and the target was easily lost in the tracking state. On May 1986 and 19, 208 radar was transferred to 630 station with 歼 8Ⅱ, ready for design and flight test, but there were still three main problems, such as large air pressure drop, unstable interception and unstable tracking, which failed to enter the flight test. By1May, 1987 18, we will focus on the end of the test flight, and finally solve the above three main problems, and then design the finalized test flight. 1988 On March 24th, the Aviation Committee approved (1988) the design finalization of the No.208 radar. 13. Practice has proved that "the adjustment and flight test of airborne fire control radar in supporting aircraft is an essential stage, and it is impossible to catch it early, do it well and take shortcuts."
But in fact, the radar does not have the real practical fire control and guidance capability of medium-range missiles, so the combat capability of the first batch of J-8II fighters has not been significantly improved, which directly leads to the inability of these fighters to equip troops. Subsequently, an improved batch of 歼-8Ⅱ 02 was formally equipped with troops and named 歼 -8B according to the naming rules issued later.