Riding the wind of rebirth

"Although liquid hydrogen and liquid oxygen technology is the 'oldest' rocket propulsion fuel technology, it has been proven that being well-fed gives you strength. At least so far, the rockets used to launch into high orbits are almost exclusively liquid hydrogen and liquid oxygen rockets."

"But it was too expensive, so scientists began to look for alternatives. Soon, the liquid oxygen-kerosene propulsion system was designed. Because of its high cost-effectiveness, it has now become the mainstream of liquid rockets."

"However, the specific gravity of liquid oxygen kerosene engines is much lower than that of liquid hydrogen and liquid oxygen engines. In other words, the price is lower and the performance is worse, but there is a big advantage: the specific gravity is higher. They can use the same cooling system as liquid oxygen. At this time, the density of kerosene can reach 1100 kilograms per cubic meter. That is to say, for the same volume, kerosene liquid oxygen rockets can carry the fuel needed to complete the mission in a smaller volume, and the rockets can be designed to be very slim."

"The downside is that kerosene has a high carbon content, which can lead to severe carbon buildup in the engine and make it unsuitable for reuse. In addition, liquid oxygen kerosene is very suitable for launching low-Earth orbit satellites, but its payload capacity decreases rapidly when launching high-Earth orbit satellites, so it cannot be used for rockets launching high-Earth orbit satellites."

"So scientists started to come up with other ideas, such as using kerosene for the first or first two stages and then replacing the last stage with liquid hydrogen and liquid oxygen, which would be cheaper and have a relatively high high-orbit capability. But this would make the rocket design more complicated."

"So scientists later developed two more propellants, nitrogen tetroxide and unsymmetrical dimethylhydrazine, which are the fuels we will be using this time."

"Theoretically speaking, this fuel has an even lower ratio than no oil, and it is highly toxic, so it has a wicked nickname in the industry - 'toxicity'."

"But why do we have to use it? Because its advantages are irreplaceable by other fuels. These are two room-temperature fuels that don't even need ignition; they can be mixed together and combusted directly to generate power. These characteristics allow rocket design to be simplified to the greatest extent possible."

"This thing is very useful in low Earth orbit operations. The country is currently developing rockets with larger payloads, which are planned to be able to carry an eight-ton payload to low Earth orbit."

"But this thing's high-orbit capability is even worse than kerosene. So to achieve high-orbit capability, we also need to combine several fuels. On the basis of a two-stage nitrogen tetroxide and unsymmetrical dimethylhydrazine, we added a smaller hydrogen-oxygen engine, plus four boosters. Thus, we achieved a geostationary transfer orbit payload capacity of 5.5 tons with a takeoff weight of 450 tons." After saying that, he pointed to the big thing on the launch pad: "Currently, our largest high-orbit launch vehicle is the Long March 3B rocket!"

"Awesome! Awesome!" Yan Xiao clapped enthusiastically. Only by coming here in person could one know what a 450-ton behemoth looked like when piled up here. And the thought that it could drop the contents of the top fairing into space 36,000 kilometers away was truly awe-inspiring.

Around noon, Li led everyone to the base canteen.

The way food is served in the base canteen is similar to that on a university campus, with a row of vegetable stalls. However, the dishes are much more refined than those on a university campus, reaching the level of the food served in Zhao Zhonggang's fire brigade.

Luo Yujuan had been keeping an eye on the entrance of the cafeteria. When she saw Zhou Zhi and the others finish getting their food, she waved for them to come over.

The reason she didn't greet them at the cafeteria entrance from the start was simple: she was having lunch with several elderly people.

Zhou Zhi recognized those elderly men. Besides Old Zhang, Old Yu, Old Wu from the post office, and Chief Engineer Luo, there was another thin but sturdy old man whom Zhou Zhi did not recognize.

"Xiao Miao is getting more and more beautiful!" Mai Xiaomiao is the apple of Zhang Laoyu's eye. Seeing her makes him beam with joy, just like seeing his own granddaughter. "I heard from the chess academy that the nonlinear computing system has made great progress again?"

"Hello Grandpa Zhang, hello Grandpa Yu, hello Grandpa Wu, hello Uncle Luo." Mai Xiaomiao greeted everyone politely while holding her rice tray, then looked at the unfamiliar man: "This grandpa is..."

"This is the chief designer of the carrier rocket series at the First Academy of China Aerospace Science and Technology Corporation. Your name is Grandpa Long." "Oh, hello Grandpa Long."

Mai Xiaomiao was quite relaxed in greeting them, after all, she had dealt with these academic bigwigs so many times, and her impression of them was that they were all kind and amiable grandparents, aunts and uncles.

But Yan Xiao and the others were stunned. Even Yang Honghui, who had practiced martial arts since childhood, had a slight tendency to lose his balance, which was caused by excessive tension.

"Everyone, please sit down and eat quickly." Old Zhang introduced this man as Long Lehao, who was also an academician. He had a military bearing and a refined demeanor. His voice was gentle, giving people the feeling that nothing could disturb his emotions, making them feel at ease and secure.

"Let me introduce you, Lao Long," Zhang Lao said with a smile. "This is Mai Xiaomiao, the inventor of the nonlinear supercomputing matrix. And this one is very relevant to you. He is Mai Xiaomiao's boyfriend, Zhou Zhi, the designer of process quality control management at the Clover Group."

Zhou Zhi, who was about to sit down, stood up again: "Hello, Academician Long."

“It would be much better if he called Xiao Miao ‘Grandpa’,” Old Long laughed. “You’re being too formal with that.”

"Grandpa Long," Zhou Zhi quickly added.

"Sit down, sit down, let's eat and chat." Academician Long finally showed some interest in Zhou Zhi, then looked at the other friends: "What about them?"

“They are my friends. They came to visit during the Yi New Year. Today, the holiday is over and they were preparing to go back. But they happened to encounter the rocket launch, so they stayed an extra day to come and broaden their horizons.”

"Oh, that's great," said Old Long. "Your group's process management system and smart terminal system have been a huge help to us!"

"It's mainly because of everyone's trust," Zhou Zhi said with a smile. "And their full cooperation. Otherwise, we wouldn't be able to help even if we wanted to. The process quality control requirements of the military industry are much higher than those of our group. So, helping you develop a process management system is actually of great significance to our own improvement."

"Young Zhou certainly knows how to talk," Old Long chuckled.

“We all call him by his nickname, Elbow, so you can call him by your nickname too,” Old Yu said with a smile. “And Le Shui, they are our lucky charms. Also, the AXA Fund’s Intellectual Property Center is a treasure trove!”

“I’m telling the truth,” Zhou Zhi said with a smile. “Take the process management system for example. The fact that we were able to design a system that meets the requirements of the aerospace industry based on the existing foundation is the best advertisement in itself. Our group can now confidently say that our process management system can cover the entire manufacturing industry, large-scale industry, and even finance, medical fields. We can also confidently say that our management method has surpassed Toyota’s lean process management system and ISO standard system. It is the most advanced, scientific, and information-rich process management system in the world today.”

"Without the stringent requirements of the aerospace industry, we wouldn't have achieved what we have today." (End of Chapter)