Chapter 11 Visit_1

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"China's largest 120-ton-class liquid rocket engine test lasts 300 seconds!"

The tractor factory caught the slander and countered with a big piece of news.

Although the 120-ton-class YF100 engine had been delivered for two years, it had not yet been improved like it would be in the future, with its thrust increased from 120 tons to 125 tons.

The maximum thrust data for the newly manufactured K120 engine during testing was 123.5 tons, indeed slightly surpassing the YF100.

By that slight margin, it's not wrong to say it is currently China's most powerful.

The maximum thrust of the other engines in active service at China's National Space Administration was only around 70 tons, until six years later, the YF130, with its 500 tons of thrust, was developed, truly marking the arrival of a powerful aerospace engine.

It was also thanks to the DX-1's straightforward structural design that a single high-thrust engine was fitted into the first stage, rather than the typical two to four smaller-thrust engines.

And there was a certain cleverness involved—the 120-ton-class engine wasn't very large; Russia and America had engines in the several hundred-ton class which made China's appear modest in comparison.

But the release of China's largest rocket engine news instantly attracted everyone's attention.

As the complete footage of the engine test was released, the voices that had been following and questioning New Yuan One's credibility suddenly vanished.

A dozen people dressed in New Yuan Tractor Factory uniforms stood in front of the camera, watching the rocket engine test video and fiercely slapped the face of those know-it-all influencers.

Especially with the title of "maximum thrust" at stake. Although it sounded improbable, upon closer inspection, it seemed to be the case indeed.

A privately-owned enterprise created China's most powerful rocket engine!

Even foreign media were surprised and shared the latest test video, which generated significant buzz.

But those most interested were the neighbors living comfortably and those constantly munching on kimchi; even their official news covered the story.

That day, when Lin Ju refreshed his dashboard, he saw the boost change from a negative 1.5% to a positive 2.2%, the effect was immediate.

The increased attention also came from the country's own space agency.

A few days later, inside the tractor factory's main assembly hall, the rocket's shell was quietly lying there.

The New Yuan One rocket was relatively small, only 31 meters high with a diameter of 2.5 meters, akin to the Long March 2 booster, which only had a thrust of 75 tons.

By then, all engines and main components of the rocket body had been manufactured, with only a handful of parts left to be installed after the main structure was complete.

Thanks to the investment and personnel support from the Southern Machinery Institute, the rocket's progress was about a week ahead of schedule, providing more time for testing and inspection.

As Lin Ju stood there, his heart swelled with pride at the sight of the nascent rocket, Deputy Director Chen suddenly came running over to deliver some news.

The factory office had received an unexpected visit request from the Aerospace Bureau Six Institute, expressing a wish to inspect the K120 rocket engine and possibly engage in commercial collaboration.

The computer on duty checked and confirmed the email address was correct, then hurried to report it.

Lin Ju was baffled and went to Baidu to search for the Six Institute, only then discovering that it was the Six Institute that designed the YF100!

Could they be eyeing the K120? Lin Ju pondered with some speculation but wasn't sure.

However, he was naturally agreeable to the visit request; after all, it was the Aerospace Bureau, a high-profile entity.

He personally sent an affirmative reply to the Six Institute. To his surprise, they responded immediately, stating someone would arrive at the factory the day after tomorrow.

Lin Ju was somewhat shocked by their speed and began to consider how to schedule the visit, which led him to seek Guo Shen's opinion.

"There isn't much to say about the New Yuan One rocket. The only thing of value is the K120, that's definitely their target. Perhaps we could arrange an engine test for that day. We're planning to do a long-duration test for 550 seconds anyway," said Guo Shen.

Lin agreed with the plan and then waited for the inspection team from the Six Institute.

On the day of the inspection, he was surprised to find that the team was led by an old acquaintance, Tang Weitian!

"Professor Tang!" Seeing the team of young and middle-aged members behind him, Lin Ju immediately understood Tang Weitian's affiliation.

"I hadn't realized you were from the Six Institute. To think that our factory received guidance from the Aerospace Bureau Six Institute!"

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"Heh, I also wanted to say, Lin Ju, please don't blame me for concealing my identity earlier, the collaboration with the Aerospace Bureau Six Institute was actually initiated by my suggestion."

Tang Weitian said this with embarrassment, but his face didn't show the slightest hint of awkwardness; he behaved as if he were completely familiar with the situation.

On the other hand, the expressions of the people behind him varied, and their eyes kept looking around. Lin Ju noticed this but chose not to comment on it.

Following the procedure, he first took the inspection team from the Aerospace Bureau Six Institute to see the first trial-produced engine prototype, with Guo Shen introducing the parameters and design concepts.

Two members of the team from the Institute were quietly discussing among themselves.

"Mr. He, is this the full flow? It clearly has one more pump than ours, but it looks even simpler, and the nozzle is smaller in diameter."

"I'm not sure, but the craftsmanship seems similar to ours. The design really is very straightforward though, and visually, there are far fewer parts, no wonder it's 700 kilograms lighter than ours, 700 kilograms!"

The man called Mr. He looked quite ordinary, but he had been deeply involved in the comprehensive design of the YF100 at the research institute.

In fact, when he heard that a private enterprise had developed a 120-ton liquid oxygen kerosene engine, he was extremely shocked.

In the 1990s, China's aerospace industry looked at a bunch of "poisonous engines" using hydrazine, which had low specific impulse and large pollution while only producing seventy to eighty tons of thrust, and resolved to research large-thrust rocket engines.

The YF100's proof of concept started from there; for its sake, China's National Space Administration even bought several RD120 rocket engines from the former Union, seeking references for their work.

The RD120 was also a liquid oxygen kerosene engine, maybe after researching for a few years and feeling that there were no major issues, the YF100 project was officially launched at the start of the new millennium.

Then, over the course of a long 12 years, the project faced numerous difficulties, with problems arising everywhere, until it finally stabilized only after its delivery in 2012.

The hardships during this period need not be mentioned in detail. Although the performance of the YF100 was only mediocre, at least it was a usable large-thrust engine.

However, suddenly someone claimed that a private company had, with a swoosh, developed a more advanced and reliable engine of the same class as the YF100!

Had it been anyone other than Professor Tang who sent the email, Mr. He would have really wanted to smash the messenger's sand pot with a hammer.

On his way here, he had already watched the first test video of the K120, which only complicated his feelings further.

Now, as he listened to Guo Shen explain the design philosophy of the K120, he felt they had made many foolish mistakes in the past, everywhere there was a sense of "this could have been so much better!"

He couldn't help but interrupt and asked, "Mr. Guo, is your engine entirely produced in-house?"

"Of course, right now, we have a simplified version of the K30 upper stage engine under production."

Hearing this, Mr. He felt even more depressed, unable to understand why others found success so easily.

He actually wanted to ask if the K120 was somehow obtained from America's aerospace agency, but alas, such thoughts could only be pondered and never voiced aloud.

Later, they were taken to witness a 550-second engine test, and when flames identical to the YF100's jetted forth, the eyebrows of every staff member from the Institute were twisted like buns.

After a whole day's visit, the folks from the Institute returned to the inn in the town with the technical documentation for the K120.

Nine of them booked the inn's restaurant to hold a meeting. As soon as the door closed, Tang Weitian's smile, which had lasted all day, finally faded.

"Let's hear it then, what are your thoughts?"

The other seven or eight people were flipping through the technical manual in their hands, and upon hearing this, all of them sighed with faces full of worry.

"It defies science, it simply defies science! This technology must be from America."

The person exclaiming about the defiance of science voiced everyone's perplexity, and they all fervently nodded in agreement.

"Exactly, we've been working on this for 15 years, we're still making improvements, and suddenly we're told someone else has succeeded just by blowing on it?"

"Full flow, small size, simple structure, and even greater thrust—with all these features, the K120 is already world-class. I feel that no matter how we modify the YF100, it won't reach this level."

"Who on earth designed this engine? It used to be so many parts, and now they're all integrated into a single structure. This isn't just genius, it means the designer must have incredibly extensive experience in engine design, either from America or the former Union. No one else could do this!"

Their many years of hard work were effortlessly surpassed, and everyone was voicing their grievances. Only Mr. He remained silent, prompting Tang Weitian to turn and look at him:

"Mr. He, what's your opinion?"