"Without legislation, it is difficult to protect long-term large-scale government science and technology projects, and it is difficult to restrain professional departments from making decisions in violation of national strategies. Whether or not the large-scale aircraft project, which has been dismounted three times, will repeat the historical tragedy of the first large-scale aircraft program, it is necessary to bring into play the power of social supervision in order to break the monopoly of a department in a high-tech professional field. And the power of public opinion is scattered and non-professional, so how can it play a real role? Personally, I think there is a need for legislative oversight. ”

"The cycle of large aircraft projects is often about 10 years, and it often spans the term of one or two governments. Judging from Airbus's successful experience in the development of the aviation industry, there has been no incident of a change of government and a plane being dismounted. Of course, the political systems of China and Europe are different, and it is worth paying attention and studying whether Huaxia needs a 'large-scale civil aircraft industry development law' to ensure the stability and sustainability of the project's decision-making and investment. ”

"Earlier, I talked about some issues related to the system and law of the large aircraft project, and now I will talk about some scientific research problems encountered in the research and development process of large aircraft."

"Although after decades of development, China's technological strength and industrial base are no longer what they used to be, but this 'Huaxia Dapeng' is like Airbus A-380 and Boeing-787 soaring into the blue sky, and there are still several technical difficulties to be overcome. The process of producing large aircraft involves a variety of disciplines, including aerodynamics, materials science, avionics, and more; The large aircraft industry involves chemical, electronic, metallurgical and other sectors, and is known as the "flower of modern industry". In order to ensure that the large civil aircraft developed by Huaxia has international competitiveness and meets airworthiness standards, it is necessary to break through a number of key technologies, including the most critical engine technology, advanced composite material technology, and long-life and high-reliability structural design technology. ”

"Taking advanced composite materials as an example, in order to meet the requirements of light weight, high strength, corrosion resistance and fatigue resistance, large passenger aircraft usually use composite materials that combine the advantages of various materials. At present, the composite materials of large passenger aircraft have been changed from the previous advanced aluminum alloy to high-strength carbon fiber, which greatly improves the performance index and reduces the cost at the same time. According to the website of Boeing and Airbus, the composite material content of Boeing-787 now accounts for 50% of the structural weight, and by 2020, all the large passenger aircraft they produce will be made of composite materials. At present, China mainly masters the manufacturing technology of metal aircraft, and the research and development and manufacturing process of advanced composite materials are quite different from the current international advanced level. ”

"Another thing that has to be mentioned is the engine. The engine is the power source of large supersonic jet airliners, and its design involves many disciplines such as mechanics, machinery, materials, and chemical engineering. The simultaneous establishment of China's large aircraft and large aircraft engines also illustrates the importance of engines. At present, China can only introduce the technology of other countries in aircraft engines. ”

"In the past few years, great progress has been made in the development of aviation equipment, such as fighter aircraft, large transport aircraft, carrier-based aircraft, armed helicopters and other advanced models have been flying into the sky, super large fuselage, faster speed, far-sea combat environment, etc., have put forward new and higher demand for aviation materials, especially the development of ultra-high strength steel. The consistent principles of long life, high reliability, lightweight and other aviation equipment development are also more clearly and directly reflected in the performance requirements of aviation ultra-high strength steel, and there are still many problems that need to be solved. ”

"Ultra-high strength steel is the strongest metal structural material at present, and aviation ultra-high strength steel represents the highest level of metallurgy in a country. Aerospace ultra-high-strength steels are mainly used as key components such as landing gear, transmission gears, main bearings and butt bolts. Everyone understands the role of landing gear in ensuring the safety of aircraft and crews, high-performance transmission gear is the core component of the helicopter transmission system, the main bearing determines the service life and reliability of the aero engine, and the docking bolt is directly related to the safety of the aircraft. ”

"The research and development of aviation ultra-high strength steel is very difficult, but it is a hot spot of competition in developed aviation countries. Among them, the steel used for the landing gear represents the highest level of ultra-high-strength steel in a country. The United States developed 300M ultra-high-strength steel in the 50s of the last century, began to be used for aircraft landing gear in the 60s, developed AERMT100 ultra-high-strength steel in the 90s, and did not develop S53 ultra-high-strength stainless steel suitable for aircraft carrier-based aircraft landing gear until the beginning of the 21st century. In the 50s of the last century, the United States spent 10 years to increase the life of the main bearing of the turbojet engine for passenger aircraft to 30,000 hours, which supported the life of the engine, but the gear bearing steel still could not meet the requirements of use. Although the strength of the butt bolt has reached more than 1800MPa, there is no ideal ultra-high strength steel. China's aircraft and engines have developed to the world's advanced level, and naturally need the world's advanced level of ultra-high-strength steel. There is still a big gap between China's aviation ultra-high strength steel and the development needs of aircraft and engines, especially the long life, high reliability, structural weight reduction and economic affordability of these key components. In order to become an aviation manufacturing power, it is necessary to reach or even exceed the advanced level of foreign countries. ”

"Like other advanced materials, aviation ultra-high strength steel is at the forefront of the discipline and needs to be completed through the application of basic theory, steel grade development, industrial production and service feedback research. The purpose of the research is to apply. Therefore, it is necessary to complete the two whole processes of 'material development' and 'material application research' in order to do a good job in key components and support the development and safe service of aircraft and engines. Aviation ultra-high strength steel should attract enough attention and receive more attention. ”

"Aviation ultra-high strength steel, like other advanced materials, has high requirements, small dosage, difficult development, and low enthusiasm of enterprises, which seriously restricts the supply guarantee. Given the special nature of ultra-high-strength steels and other advanced materials for aviation, the aviation industry must plan for its own supply security. In order to solve this problem, there have been decades of ideas and attempts, such as building a small-batch trial production, production and supply plant in a materials research institute, but so far it has not been successful. ”

"I've thought about how to solve the problem, but I haven't found a good solution, after all, I haven't practiced it. I think that there are three issues that need to be considered to solve the problem of small-batch trial production, production and supply of key materials for aviation and military industry. The first is to ensure that the requirements are met, the second is to combine peacetime and wartime, and the third is to achieve high efficiency. The disadvantage of the material research institute attached to it is that it cannot be combined with peacetime and wartime, and the reason for the low enthusiasm of the enterprise is that the efficiency is low. ”

"The best solution should be to set up a special trial production line in the enterprise. It can not only transform the advanced technology brought in by the research institute into production technology, drive its large-scale production technology to improve its level, accelerate the value-added, upgrading and transformation of products, but also ensure that it will immediately switch to mass production in wartime. Moreover, aviation ultra-high-strength steel and other advanced materials that do not meet the high quality of aviation can be used as general aviation components, and lower quality materials can be used for other military components or civilian components. It is very important to establish a high-level special small batch trial production and production line in the enterprise, and the research institutions cannot solve the problem of materials for large-scale production, and non-large-scale production materials cannot be used as key components of aviation. For example, for more than 60 years, Fushun Steel Plant has been a manufacturer and supplier of aviation ultra-high strength steel and high-temperature alloy materials, with the highest technical level in China, and almost all of the aviation ultra-high strength steel and high-temperature alloy materials that have reached the physical level of the United States are also trial-produced by Fushun Steel Plant. The establishment of a special small-batch trial production and production line in Fushun Steel Plant should be able to meet the needs of aviation ultra-high-strength steel and high-temperature alloys. With the rapid development of the aviation industry, the requirements for the small batch production and supply of aviation ultra-high strength steel and high-temperature alloys and other materials are getting higher and higher, and investment should continue to be increased. ”

……

Since the successful realization of the dream of astronautics, another important dream of flying that Huaxia has been planning since the founding prime minister - building Huaxia's own large aircraft, has finally set sail again after 20 years of freezing. While the giant aircraft with millions of parts and components across almost every engineering discipline are known to all as the 'flower of industry', no country has been able to break through the skies of Boeing and Airbus until now. ”

"Even if you attack that beach, even if you get into that mountain, even if you take that island country, you will never reach the other side. Like the 'Granma' that carried more than 80 hot-blooded men such as Castro and Guevara to sea in the Gulf of Mexico on the night more than 40 years ago, Huaxia Aviation Industry, which has been defeated and defeated again and again, still started another voyage without seeing the horizon, knowing that the road is long, difficult and tragic. ”

At this end, Professor Gong walked up to the podium, picked up the microphone and said: "Thank you Miss Zhao Zhiying for her wonderful speech, she gave us a very intuitive and clear understanding of Huaxia's large aircraft project. It can be summed up in one sentence: the future is bright, the road is tortuous, which requires us to work hard to complete and struggle. The following is the question time, students who have questions can ask Ms. Chi Tsz Ying questions. ”

There is this kind of opportunity to communicate with the beautiful sisters of the Academy of Sciences on an equal footing, of course, the students will not let it go, and in an instant, many people who have been prepared immediately raised their hands.

Wang Liheng on the side saw that there were a lot of people asking questions, so he was busy talking to the side: "That's it, there are too many people, I'll help Senior Sister Zhao screen a few people to ask questions on behalf of you, okay?" ”

The students knew that it was impossible for everyone to have a chance to ask questions, so they all agreed.

"Zhang Jiawei, you are the best student in our class and the secretary of the party branch of the class, you can ask this first question." With a slight expectant smile, Wang Liheng pointed out Zhang Jiawei's name without warning, but in fact, Zhang Jiawei didn't raise his hand at all just now, so it is conceivable that the goods just wanted Zhang Jiawei.