On February 11, China used the Long March 8A carrier rocket (also known as the Long March 8A carrier rocket) at Wenchang Space Launch Site, successfully launched the satellite Internet LEO 02 group of satellites, successfully entered the scheduled orbit, and the launch mission was a complete success, marking the addition of a new generation of carrier rocket family in China. Song Zhengyu, the chief designer of the Long March 8A carrier rocket at the First Academy of China Aerospace Science and Technology Corporation, introduced that the Long March 8A carrier rocket is developed based on the Long March 8th carrier rocket and improved to meet the future needs of launching a network of medium and low orbit giant constellations. It uses the core stage and booster of the Long March 8 carrier rocket, with the core stage being a newly developed 3.35-meter diameter universal hydrogen oxygen upper stage equipped with a 5.2-meter diameter fairing. It, together with the basic type of Long March 8 carrier rocket and the series configuration of helpless thrusters, forms the Long March 8 series carrier rocket, forming a solar synchronous orbit 3 ton, 5 ton, and 7 ton level carrier capacity echelon, effectively enhancing China's low and medium orbit satellite network launch capability Song Zhengyu said. Song Zhengyu revealed that the Long March 8A carrier rocket innovatively integrates the functions of satellite brackets, adapter frames, and instrument modules into a multifunctional module, successfully reducing the weight by 200 kilograms and improving the rocket's carrying efficiency. The application of this integrated design method in rocket structures is the first of its kind in China. In addition, as the first rocket to use a 3.35-meter diameter upper stage with a 5.2-meter diameter fairing configuration, the Long March 8A carrier rocket appears to have a larger "head" in appearance, providing more space for satellites to ride and adapt to more types and larger volumes of satellites, with stronger mission adaptability. What are the outstanding features of the newly developed 3.35-meter diameter universal hydrogen oxygen final stage? Fan Chenxiao, the designer of the First Institute of China Aerospace Science and Technology Group, said that it can carry more fuel and has adopted new technologies, new products and new processes, such as new foam sandwich bottomed storage tanks, closed expansion cycle engines, and new electronically controlled relief valves, which have significantly improved the transport capacity, effectively shortened the satellite's orbit entry time, saved fuel, and improved the satellite's life. The upper stage of a rocket fueled by liquid hydrogen and liquid oxygen has the characteristic of high specific impulse, which enables the rocket to obtain relatively large thrust with less fuel. It is currently the propellant with high specific impulse that China has mastered Liu Lidong, a designer at the First Academy of China Aerospace Science and Technology Corporation, said that in the spectrum planning of China's new generation of medium to high orbit launch vehicles, the main configuration of future medium to high orbit launch vehicles will adopt a hydrogen oxygen upper stage. Liu Lidong introduced that before the emergence of the universal hydrogen oxygen upper stage, China only had a 3-meter diameter hydrogen oxygen upper stage, which could no longer meet the development needs of China's new generation of medium-sized carrier rockets in terms of rocket body diameter and power system optimization. The selection of hydrogen and oxygen final stage module for universal design can meet the requirements of the following new generation of medium-sized rockets in China to unify product specifications, improve the degree of module level productization, improve production efficiency and further reduce costs. Song Zhengyu stated that the 3.35-meter diameter universal hydrogen oxygen upper stage will serve as a mature module for other rockets to choose from in the future, effectively enhancing the carrying capacity of the Long March series carrier rockets. Behind the successful launch of the Long March 8A carrier rocket is the vigorous development of China's aerospace industry in recent years. Exploring the vast expanse of the sky, the Long March series of carrier rockets witness each departure and journey. The first launch of the Year of the Snake has a good start, and China's aerospace industry is sure to achieve its goals and embark on a new journey towards the stars and the sea! (New Society)