Siheyuan (traditional courtyard house): Starting with the Korean War, returning home to take charge

On the day the documents were sent out, He Yuzhu sat in his office until the early hours of the morning.

Three packages of "RDX Production Process" documents were wrapped in kraft paper, with addresses listed as Luzhou, Qingyang, and Taiyuan respectively. He stacked the three packages on the corner of the table, then picked up the top package, opened it, and pulled out the first page to read through. Molecular formula, synthesis route, process flow, safety regulations. He had read those words countless times; he could recite them from memory with his eyes closed. He then stuffed the paper back in and resealed it.

A gust of wind picked up outside, making the large-character posters on the courtyard wall rustle loudly. He stood up, walked to the window, and drew the curtains tightly. Returning to his table, he picked up the phone and dialed the number for the Luzhou Chemical Plant. After several rings, a young voice answered, sounding sleepy.

"Where is the factory manager? Our factory manager just left, you..."

He Yuzhu interrupted him. "No need to look anymore. Tell him tomorrow that the documents were sent out today. Have him call me back after he receives them."

A voice answered, and then hung up. He Yuzhu dialed Qingyang, then Taiyuan. After saying the same thing, he put down the phone and leaned back in his chair. All three lines were crucial; none of them could be disconnected.

Half a month after the materials were sent out, all three factories called.

Luzhou was the first to attack. The engineer there, surnamed Zhou, spoke quickly, like a machine gun. "Director He, the temperature of the nitration reactor is out of control. It starts to fluctuate when it reaches 80 degrees Celsius, jumping up and down by 15 degrees. We tried three batches, and all three failed. One batch almost exploded; the reactor lid even popped open."

He Yuzhu held the microphone. "Should the lid be lifted?"

Engineer Zhou said, "It's working. The safety valve released pressure, and no one was injured. But the workers dared not get too close; they all retreated to outside the safety line to operate."

He Yuzhu remained silent. He recalled the year they were developing anti-tank missiles; the first test launch exploded, and Ma Yuejin squatted on the ground picking up the shrapnel. Developing new technology, you can't succeed without a few failures.

"Can the temperature control system be modified?"

Engineer Zhou said, "Yes, it's possible. But we'll need to replace the controller. We're using an older model, which isn't precise enough. We need a computer-controlled one; they have them in Shanghai."

He Yuzhu said, "I'll go coordinate. You wait."

After hanging up in Luzhou, another call came in from Qingyang. The factory manager there, surnamed Zhao, spoke slowly, enunciating each word carefully.

"The centrifuge is faulty. The rotation speed is insufficient, and the purity of the separated product is only 85%. We took it apart and found that the bearings are severely worn; this machine has been used for almost twenty years."

He Yuzhu said, "We're getting a new one. A high-speed centrifuge will be shipped from Shanghai and arrive next week."

Factory Director Zhao said, "Okay."

The third call came from Taiyuan. The engineer there was surnamed Sun, and his voice was hoarse, as if he had a wad of cotton stuffed in his throat.

"The problem lies in the drying process. The hot air temperature is uneven, higher in the middle and lower at the edges. The middle layer is burnt, while the edges are still wet. We've tried several methods, but none of them work."

He Yuzhu thought for a moment. "Vacuum drying? No need for hot air, just vacuum drying at a low temperature."

Engineer Sun was silent for a few seconds. "We've never done vacuum drying before. We don't have the equipment."

He Yuzhu said, "The equipment will be transferred from Beijing. You should prepare the venue first."

After making three phone calls, He Yuzhu put down the receiver, his palms sweating. He stood up, walked to the wall, and looked at the map. Luzhou was on the banks of the Yangtze River, Qingyang on the Loess Plateau, and Taiyuan on the banks of the Fen River. Three places, three sets of equipment, three problems. He turned around, picked up the phone, and dialed the number for the Chemical Research Institute.

"Director Chen, come here."

Chen Dehou arrived quickly, still carrying that old canvas bag. He sat down opposite He Yuzhu and placed the bag on his lap.

"Director He, I've heard about the situations at all three factories. The temperature control in Luzhou, the centrifuges in Qingyang, and the drying in Taiyuan—none of them are easy to handle."

He Yuzhu pushed a copy of the three warranty documents in front of him. "You make a trip there. Luzhou, Qingyang, Taiyuan, one after another. Stay at the factory, help them solve the problem, and then come back."

Chen Dehou picked up the three packages of documents, stacked them together, and wrapped them in a canvas.

"I'll go to Luzhou first. It's the most urgent there. If the temperature control can't be handled, nothing else can be done."

He Yuzhu nodded. "You decide."

Chen Dehou stood up, walked to the door, then turned back. "Director He, if this thing is successfully developed, can our missiles penetrate the T-64?"

He Yuzhu looked at him. "Yes."

Chen Dehou nodded, pushed open the door, and left.

Chen Dehou stayed in Luzhou for ten days. He Yuzhu waited for his call every day. There was no news for the first two days, but the call came on the third night.

"Director He, the temperature control has been fixed. The computer controller that was brought in from Shanghai has been installed, and the temperature is stable within ±1 degree Celsius. We've tested two batches, and the response is normal with no fluctuations."

He Yuzhu held the microphone. "What about the purity?"

Chen Dehou said, "The initial measurement is 92%. It's still not enough, but it's much better than before. We'll continue adjusting."

On the fifth day, Chen Dehou called again. "The purity has reached 95%. The nitration reaction is stable; the next step is separation."

On the seventh day, he went to Qingyang. He stayed there for five days, replacing the centrifuge with a new one; the speed was sufficient, and the purity reached 96%. On the thirteenth day, he arrived in Taiyuan. The vacuum drying equipment was transferred from Beijing, and installation and debugging took three days. After the first batch came out, he called, his voice hoarse.

"Hehe, it's done. The purity is 97.5%. All three meet the standards."

He Yuzhu didn't speak. He heard someone shouting on the other end of the phone, but the voice was far away and he couldn't make out what they were shouting.

"Come back. Next step: scale up production."

Luzhou was the first to ship out a batch. Fifty kilograms of RDX, packed in sealed barrels, were transported to Beijing by special train. He Yuzhu went to the platform to receive them; it was still dark. The train car doors opened, and workers unloaded the metal barrels, two people lifting them, moving them step by step, careful not to let them sway. A "Danger" label was affixed to the barrels, red background with black lettering, and one corner curled up.

Chen Dehou opened the bucket lid, scooped out a little with a small shovel, and placed it on a piece of white paper. The pale yellow crystals were fine and fragmented, gleaming faintly in the dim light of the platform. He handed it to He Yuzhu.

He Yuzhu took it and pinched it with his fingers. It was hard and not sticky. He smelled it under his nose; there was no strange odor.

Chen Dehou pulled a test report from his pocket and handed it over. "Purity 97.5%. Explosion velocity 8,800 meters per second. Thirty percent more powerful than the explosives we use now."

He Yuzhu folded the report and put it in his pocket. "Send it to the firing range. Load the ammunition and test fire."

The firing range was located in the mountains of Changping. When He Yuzhu arrived, it was just dawn. The anti-tank missiles were already loaded with new warheads, new shaped charge shields, and new RDX explosives. The launcher was set up beside the firing range, with the missile standing upright on it, its pointed warhead gleaming coldly in the morning light.

The target plate was transported from the steel mill; it was made of homogeneous steel, 250 millimeters thick, the same thickness and angle as the frontal armor of the Soviet T-64. Ma Yuejin squatted in front of the target plate, touched the steel surface with his palm, and then stood up.

"Dean, can this thing be penetrated?"

He Yuzhu didn't answer. He looked at the missile, the target plate, and the busy technicians. The launch operator sat at the control panel, his fingers on the launch button, veins bulging on the back of his hand.

"put."

The missile shot off the launch pad, trailing an orange-red plume, flying faster and lower, skimming the ground as it hurtled towards the target plate. He Yuzhu stared at the plume, watching it crash into it.

boom--

A burst of fire erupted, billowing smoke. Shards flew everywhere; a palm-sized piece of iron flew over He Yuzhu's head, shearing off several branches of the pine tree behind him. When the smoke cleared, He Yuzhu walked over and squatted in front of the target. There was a hole, its edges curled up and blackened, through which he could see the sky. He reached out and touched the edge of the hole; it was hot.

Ma Yuejin followed and squatted down to look. He didn't touch it; he first squinted and peered into the hole, then stuck a finger in, circled it, and pulled it back.

"I wore it. From start to finish, there wasn't a single hindrance."

He Yuzhu stood up and turned around. Some of the technicians were squatting on the ground, some were standing behind the target, and some were recording data. A young technician ran behind the target, picked up a shattered piece of debris from the ground, held it above his head, mouth open, but didn't shout. He glanced back at the hole to make sure the light was really coming from there, then suddenly turned around and shouted at the crowd—his voice was shrill and broken, as if something was blocking his throat.

"I'll wear it!"

Others joined in the shouting. Some jumped, some clapped, some crouched on the ground covering their faces. Chen Dehou didn't move. He stood at the back of the crowd, his reading glasses askew, uncorrected. He stared at the light-filled hole, his lips moving slightly, as if counting something. Someone next to him tugged at his sleeve, saying, "Engineer Chen, it's done." He grunted in response, but still didn't move. After a long while, he finally stretched out his hand, gesturing in the air to show the diameter of the bullet hole, then pulled his hand back and put it in his pocket. His hand was trembling; he didn't want anyone to see it.

Ma Yuejin walked over and opened the notebook in his hand. "Director, the penetration depth is 260 millimeters. That's 10 millimeters higher than the design requirement. That's enough. The Soviet T-64 has a frontal penetration of 250 millimeters and an angle of attack of 68 degrees. Our missile can penetrate that."

He Yuzhu didn't speak. He walked to the front of the target platform and glanced at the hole again. The edges were curled up, blackened, and the mountain behind it was visible. He turned around and walked out of the shooting range.

The voice in my head rang.

[Hidden Mission: Triggering a New Type of Explosive]

[Mission Objective: To achieve the domestic production and application of RDX explosive]

[Mission Reward: 100,000,000 points]

He glanced at it but ignored it.

That evening, He Yuzhu sat in his office and took the list out of his drawer. Turning to the page on "explosives," after the words "RDX," he wrote a few lines: "Collaboration between factories in Luzhou, Qingyang, and Taiyuan; production in three months. For use in anti-tank missiles; penetration depth 260 mm, capable of penetrating the equivalent armor of a T-64."

After finishing writing, put the list back and lock the drawer.

The missiles could penetrate, but who would they hit? Where were those T-64s parked? He remembered clearly a line in the border regiment's last briefing, written in pencil: "No tanks seen at the training ground across the way for half a month; suspected to have moved forward." Moved forward to where? How far from the border? He reached for the black telephone on the table but didn't pick it up. He was waiting. Waiting for Yang Xiaobing to come out of the next room. Waiting for him to say, "Regimental Commander, ready." Waiting for him to ask, "Where to?" and for him to answer, "Crossing the border."

The wind outside suddenly picked up, rattling the window frame with a loud clang. He didn't turn around.