Aviation gun patent

After several years of careful preparation and repeated brewing, the aviation industry has begun to develop new high-altitude high-speed fighters. 1964 in may, the institute of aeronautics proposed at the meeting of new aircraft improvement scheme that a fighter with better performance should be designed on the basis of MIG -2 1. In the same year 10, the new fighter began to demonstrate the 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. Its main development work is undertaken by Shenyang Aircraft Design Institute and Shenyang Aircraft Factory. National leaders are very concerned about the development of the J-8 aircraft. 1August, 965 14, Vice Premier He Long instructed: "The J8 should be produced as soon as possible" when listening to the report on the development of the J8 in Shenyang. On August 18, in a letter to Deputy Chief of Staff Zhang Aiping, Marshal Nie Rongzhen 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. The development scheme 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, improvements were made item by item, and all performance indexes were improved: (1) The maximum speed was Mach number 2.2; (2) The maximum ceiling is more than 20,000m; (3) The maximum climbing rate is 200m per second; (4) Basic voyage 1500 km, with a maximum voyage of 2,000 km; (5) stipulated the air combat time at an altitude of 1.9 million meters; (six) the installation of improved design of aircraft guns and air-to-air missiles; (seven) the installation of radar with large search distance. This 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 this year, 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 year1February, the wooden prototype of the J-8 aircraft passed the examination. 1March, 1966, designers went to the factory to carry out on-site design with workers and technicians. At the end of 1966, a complete set of aircraft drawings was issued, and at the beginning of 1967, the corresponding production documents were issued, and the factory immediately began 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. Technicians from 60/KLOC-0 Institute, Shen Fei Factory and Aerodynamics Research and Test Department, together with Beihang University and Professor Xu, have done 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 of 62 1 research institute and casting expert, proposed to adopt hollow air-cooled 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 institutes 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, the first cast porous air-cooled nickel-based superalloy blade in China was developed, which was completely successful after being installed on 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 on 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. This time, designers and workers did experiments together, modified an air gun that can simulate shooting and fired 10 thousand fake bombs. Finally, the law was found and the design was successful. In the second half of 1965, Shenyang Aircraft Factory began to prepare for the trial production 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 1966 1 29. 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. 1966 1 1 month, after Liu Hongzhi was forced to stop work due to unfair treatment during the "Cultural Revolution", the factory jointly established the 歼 8 R&D headquarters, and Wang Xin, the deputy director of the factory, was responsible for the overall organization and leadership. Factory employees cooperate and support each other, creating a good working atmosphere. 1967, under the impact of the "January Storm" and the "Cultural Revolution", the production order of the factory was seriously damaged, and the production on the production line almost stopped. The vast number of scientific and technological personnel and workers even risked their lives to go to work. Even in July and August, when the fighting was the fiercest, the development of J-8 didn't stop. 1July, 968, the first batch of two 歼 8 aircraft completed the final assembly. 1On July 5, 969, the J-8 aircraft made its first test flight. 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. At this time, people standing at the airport gave a warm cheer. Hail the success of the first flight of China's first self-designed high-altitude high-speed fighter. From the conceptual demonstration to the first flight, the J-8 aircraft experienced four years and ten months, including general layout, technical design, wooden prototype evaluation, drawing distribution, new machine manufacturing and testing. This speed is relatively fast. Of course, this speed is not accidental, for the following reasons: it started steadily, and the design of the J-8 was based on the "technical understanding" of the MiG-2/KLOC-0 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. 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 replaced by 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 China Institute of Aviation Industry and relevant units of the Ministry of Metallurgy, which ensured the smooth flight of the whole aircraft. Mobilize all positive factors and give play to collective wisdom. In the trial-production process, the combination of "scientific research, production and use" and "leading cadres, workers and technicians" was implemented, and Qi Xin worked together to 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. Technical data span: 9.34m Captain: 2 1.52m Aircraft height: 5.4 1m Wing area: 42. 19m2 Normal takeoff weight: 13850kg Maximum horizontal flight speed: M2.2 (high altitude) Service ceiling: 20500m.