Courtyard House: Starting with a 28-inch motorcycle

The last key material for the new fighter jet has successfully passed verification and will soon enter the mass production stage. The new generation of warplanes will be deployed at an accelerated pace, and an overwhelming advantage must be achieved in terms of scale.

Inside the research institute, the lab tables were brightly lit, and the team members were all focused on debugging equipment and recording data. Yan Xudong followed closely behind Xiao Yao, holding the instruments and operating them one by one—Xiao Yao not only supervised the site, but also demonstrated step by step, breaking down and explaining the core fundamentals of material synthesis, stress testing, and microstructure analysis to him.

"Teacher, I heard that you have excelled in many fields and made a name for yourself in each one. What's your secret?" Yan Xudong interjected during the break.

"Oh, you're interested?" Xiao Yao raised an eyebrow and smiled.

"Can I continue learning from you?" His gaze was intense, and his tone was not at all joking.

Xiao Yao paused, looking at his taut shoulders and shining eyes, then suddenly laughed loudly: "Alright! As long as you can digest it and delve deep enough, I'll teach you to the end." As soon as he finished speaking, he nodded steadily and forcefully.

Talent isn't something you can just force out; but if someone doesn't even have the courage to reach out, then even the best seedling will remain buried in the soil. Rather than blocking the way, it's better to first create a crack.

Yan Xudong grinned, his eyes relaxing.

Several trainees watched silently, their eyes shining, but they didn't say a word—they knew in their hearts that it would be enough for them to just focus on one main area and gain a foothold in a specific niche.

Xiao Yao never teaches his students by rote. While others memorize formulas and draw diagrams, he insists that everyone roll up their sleeves and work together to mix slurry, press boards, and test impacts, all while figuring out the principles. The fiber composite material they've developed has extremely high value for both military and civilian applications: it can be embedded in the core layer of bulletproof vests, and can also be used in high-end sports equipment, mining protective clothing, and even medical stents.

Traditional bulletproof layers rely on metal alloys, ceramic sheets, fiberglass, or nylon fabrics. This time, the focus is on two high-molecular fibers: nylon (i.e., polyamide fiber) and ultra-high molecular weight polyethylene (UHMWPE) fiber. The latter can be called the "ceiling" of the fiber industry: it currently has the highest specific strength and top specific modulus in the world, and is tear-resistant, corrosion-resistant, and has an extremely long bending life. It is resistant to knife cuts and bullet penetration.

Of the world's three major high-performance fibers—aramid, carbon fiber, and UHMWPE fiber—China has made breakthroughs in the first two. However, UHMWPE has long been hampered by foreign countries, lacking both mature production lines and systematic teaching materials, and even decent references are scarce.

When Professor Xu first saw the project application that Xiao Yao handed him, his hand trembled and he almost knocked his glasses askew. "Xiao! Are you really going to tackle this tough nut? Why don't you try a different approach first? This isn't something you can accomplish just by being ruthless!" He spoke earnestly, afraid that the young man might narrow his path by stubbornly sticking to his guns out of pride.

Xiao Yao didn't mince words: "It is indeed difficult. But no matter how difficult it is, someone has to overcome it. Materials are our weakest link—if the supply were to be cut off one day, we wouldn't even be able to make bulletproof vest linings, how would we protect our soldiers?"

Old Xu paused for a moment, then suddenly slammed his hand on the table and stood up: "Good! I fully support you! I believe you can take it down!" His voice was loud and clear, and his eyes were burning with fire.

As soon as the material project was approved, Xiao Yao immediately gathered everyone together. Standing in front of the projection screen, he used the most straightforward language to break down the molecular chain configuration, crystallinity control, and hot pressing molding logic... Every sentence was practical and there was not a single empty word.

At the same time, in the old leader's office, the news that the first new fighter jet had completed its final assembly was already on his desk.

He tapped his fingers lightly on the table, flipping through the report repeatedly, his smile deepening—behind every page of data lay the marks of independent breakthroughs. Compared to the expensive models imported in earlier years, this fighter jet not only boasts several generations of improved performance but also achieves full localization of the supply chain, significantly accelerating the pace of mass delivery.

Seeing that the core components, such as the engine, radome, and wing load-bearing frame, were all made by Xiao Yao's team, he couldn't help but ask, "Comrade Xiao Yao, you haven't been with the institute for very long, have you?"

The secretary quickly responded: "It took less than three months, from receiving the order to the successful test run on the aero-engine bench, the entire process took no more than ninety days."

The old leader tapped his cigarette against the ashtray, a spark flying: "Give him the strongest security! We can't let that close call happen again—they were already inside the cordon before we realized what was happening, too risky!"

"Immediately!" the secretary replied and turned around.

Xiao Yao was too young, and his achievements were too dazzling to hide. Fortunately, almost no one outside had ever seen him in person. Overseas intelligence networks have yet to uncover a clear picture of his face, nor have they found any trace of him during his school days—his student record has long been cleared from the school archives; even his transcripts have no record of him; only the old teachers who taught him back then, when they occasionally mention that tall, thin boy who always sat in the front row and whose questions went straight to the point, will still pause slightly in surprise.

……

Xiao Yao's civilian-grade bulletproof vest features a multi-layered blended fiber structure, making it lightweight yet robust.

Of course, unlike the models currently in service with the military—it doesn't need to be deployed on the front lines, so its protection standards don't need to be comparable to those used in heavy firepower battlefields. Being able to withstand direct fire from high-velocity sniper rifles like the Mauser 98K is more than enough; after all, people who can actually get close are most likely only holding a pistol or submachine gun, which are small, easy to carry, but pose a very precise threat.

The military version is a different story: it requires the addition of special steel plates and amorphous alloy sheets, making the whole set thicker and heavier, but still able to withstand 12.7mm armor-piercing rounds. But Xiao Yao refused to accept this fate—he insisted on finding a new material that was lighter, stronger, and more flexible. Since it was for soldiers' protection, he wanted it to be perfect: wearing it, one could run, crawl, climb, and most importantly, return alive.

Besides nylon and UHMWPE, he also discovered several unnamed heterogeneous fibers in the laboratory space, whose engineering potential has not yet been thoroughly verified. Currently, he and his team are starting from the most basic aspects, such as solvent selection, spinning temperature, and draw ratio, to dismantle the black box of the process step by step.

The success of the previous rounds of material development had already ignited everyone's fighting spirit. At this moment, dozens of eyes were fixed on Xiao Yao, notes were being taken at lightning speed, and even breathing was unconsciously softened—as if the next second, he would personally push open the door to a new era.

With readily available reference samples, the research and development process went much more smoothly than expected. These core materials had to be mastered one by one and developed independently before they could officially enter the integration stage of the bulletproof vest.

"Now we will start the special suspension impregnation process, conduct parallel experiments in groups, and compare the final protective effectiveness—whichever solution is better will be the path we choose."

Xiao Yao made arrangements in a deep voice.

"Understood, Professor Xiao!" the students responded in unison.

Gazing at the sample undergoing gel solidification, Yan Xudong felt a surge of emotion, a mixture of awe and admiration. As he rapidly recorded the parameters, he exclaimed sincerely, "Professor, you've truly given your all to this research! Since the project started, you've worked dozens of consecutive all-nighters, even neglecting to queue for food in the cafeteria—we should really put your schedule on the lab door as an inspirational wall!"

Xiao Yao cleared his throat somewhat awkwardly. It wasn't as miraculous as he made it out to be. He was just gritting his teeth, hoping that the country could use its own materials in the future, without having to pay for foreign patents anymore.

Seeing the dazzling light in Yan Xudong's eyes, he ultimately didn't explain further—some admiration is more heartwarming to leave unsaid than to expose it.

Over the past three months, the team has strictly followed Xiao Yao's design logic, repeatedly deducing, testing, and optimizing, finally bringing the D3O material from blueprints into reality.

This material is usually soft like cotton, draping, flexible, and close-fitting; but once it encounters a high-speed impact or sudden compression, the internal polymer chains instantly "interlock" and harden into a dense barrier in milliseconds, dissipating the kinetic energy layer by layer; after the external force is removed, it quietly relaxes back to its original state, as if nothing had happened.

It can respond to impacts of varying intensities within nanoseconds, switching between rigid and flexible states in real time.

Essentially, this is a typical non-Newtonian fluid—completely different from "obedient" fluids like water and engine oil.

Actual test data clearly shows that the stronger the impact, the harder the material; a light touch is imperceptible, but a heavy blow feels like iron.

This is precisely the "intelligent armor substrate" that Xiao Yao has been searching for. Next, it will be deeply interwoven with ultra-high molecular weight polyethylene fiber and nylon matrix to form a new generation of composite bulletproof system.

The young people in the project team, who had just taken off their master's gowns, stared at the finished product in front of them, speechless for a long time. They had only seen D3O "theoretically" in literature before, and they never dared to believe that they had personally dragged it from the paper into reality.

Some people suddenly squatted down and wiped away tears, while others hugged their companions tightly, choking back sobs and unable to utter a complete sentence. There were no cheers, only sobs and trembling shoulders—the weight of the era's leap forward was sometimes so heavy that only tears could support it.

On the day the first composite bulletproof vest was produced, Xiao Yao frowned: Without a gun, how can we test its hardness?

"Teacher, what's wrong?" Yan Xudong noticed his somber expression.

"It's not that it's bad... it's that we can't test it." Xiao Yao smiled wryly. "We can't exactly throw bricks at it, can we? We have to use live ammunition."

Before the results were verified, he was unwilling to alarm his superiors—fearing that a false alarm would dampen the nascent enthusiasm of everyone.

"Teacher, have you forgotten where we are?" Yan Xudong reminded him with a smile, "We may lack other things, but we have plenty of bullets."

Xiao Yao slapped his forehead: I'm really confused by the data! This is a military research institute, not a university laboratory—even old-fashioned Mauser pistols are neatly arranged in the standard-issue armory.

The group quickly left the lab and headed straight for the security office. The officer on duty was taken aback: Why were all these people in white coats out together? Had someone lost their laptop?

"Professor Xiao, what happened?" Captain Zhang Jie rushed over. He was Xiao Yao's personal bodyguard and the institute's chief security coordinator. Seeing the commotion from afar, his heart immediately jumped into his throat.

"Captain Zhang, the new bulletproof vests have arrived. Borrow your guns and let's test them on the spot." Xiao Yao waved the gray-blue thin armor in his hand.

Zhang Jie's pupils contracted, and without saying a word, he immediately ordered two top-notch snipers to accompany him to the shooting range.