Chapter Fifty-Four: I Have Returned

"Yang, come with me quickly, the castings are back. I guarantee you'll be amazed."

Yang Hui sat in the office all day, doing nothing but reading quietly, not visiting the main project team, simply waiting here for good news from several directions. The production cycles of the various components differed, but the longest ones had started trial manufacturing ahead of time, so whether good or bad, they would all return today.

The first success report came from the second batch of trial centrifugal impellers. Seeing Zhong Jian's excitement, Yang Hui finally felt some relief—at least one had made it back.

Putting aside the book he'd been unable to focus on, Yang Hui followed Zhong Jian downstairs, his steps light and brisk.

"Jian, judging by your expression, the trial parts must have turned out well this time, right?" Yang Hui couldn't help but ask Zhong Jian, even though he knew he'd soon see the impeller himself.

"Yang, I can't describe it in words. My feelings right now are beyond explanation; you'll understand when you see it."

Such excitement is hard to convey, and Zhong Jian was certainly experiencing it. This was the first product he'd designed that might enter mass production, so his enthusiasm was palpable.

Since it couldn't be described, Yang Hui decided to wait a bit longer—once he saw the impeller, he'd know. Even as a seasoned, mature man, Yang Hui found himself as excited as these young people; youth, it seemed, was contagious.

They arrived at the box holding the impellers, and Yang Hui was surprised to see nearly half a box filled. Though separated by straw, there were at least fifteen or sixteen in the box.

"So many? How many did you make?"

Hearing the question about quantity, Zhong Jian grinned, "Yang, there are seventeen finished impellers, out of twenty total. After heat treatment, shaping, rust prevention, and rough machining, we ended up with seventeen."

The success rate was clearly high; this batch of impellers seemed genuinely suited for mass production. Yang Hui picked up one to examine it. Surface roughness was not a concern—cast parts never have perfect finishes—but in other respects, it looked good. After post-processing, the impeller appeared quite decent: no sand holes or air pockets, and the shaft bore was well machined, with a good initial impression. Internal casting flaws couldn't be seen, but the factory inspection sheet declared them qualified, meaning no issues.

"How about it? These parts were made by the same senior engineer as last time. He praised this batch, saying it was the highest yield of any trial he's worked on."

It was no surprise—the impeller had been simplified to such an extent that a high success rate was expected.

Yang Hui carefully put the impeller back, separated by straw to prevent collision with others, nodded, and smiled, clapping slowly, "Excellent, excellent. These impellers are quite good. Your design is outstanding."

He flexed his hands and feet, noticing there were no carts or vehicles nearby. The distance from the institute gate to the testing center wasn't far but wasn't near either. He steeled himself.

"Let's go. There aren't any carts here, so we'll have to use muscle." He checked the box for sturdiness—it was quite solid, as products made these days tended to be.

Seeing the team leader preparing to roll up his sleeves and work, Zhong Jian dared not stand idle. He quickly joined Yang Hui, and the two of them hoisted the box, carrying it to the testing center. Their crab-like posture attracted many curious glances; there was a certain inexplicable pride in their stride.

On the way to the testing center, people occasionally stopped to lend a hand, and so, relying on manpower alone, they hauled the heavy box to its destination.

Sweating profusely, Yang Hui and Zhong Jian exchanged smiles—it was tough, but they'd managed. This journey was one of perseverance, and in the coming winter of the military industry, only perseverance would see them through.

Yang Hui patted the sturdy box and, smiling, went into the testing center to find someone. Last time, it had been Chief Wu who introduced him to Chief Li. This time, Yang Hui and Zhong Jian came on their own, so it was up to him to make contact.

"Who are you, and who are you looking for?"

Chief Li clearly didn't remember Yang Hui, whom he'd only met once.

Now, Yang Hui was on someone else's turf and needed to be cautious, though Chief Wu had told him Chief Li was easy to talk to.

"I'm Yang Hui, the one who came last time for the combustion chamber test." Identifying himself was the safest way.

"I see, you came with Chief Wu, right? Bringing new parts this time?" Mentioning the small combustion chamber jogged Chief Li's memory.

"Yes, we've produced our impeller and brought it for testing."

Since they'd come for inspection, Chief Li picked up his clipboard and walked outside with Yang Hui to examine the new parts.

Seeing Yang Hui with someone who looked like a supervisor, Zhong Jian quickly stood up from the box, dusted himself off, and prepared to open it.

"No need, let's carry it inside first." Chief Li set down the clipboard, tried to lift the box, and found it quite heavy.

"It's really heavy—how much is inside?" He was puzzled; aircraft engines shouldn't be so heavy, so the box must be packed with parts.

"It's just a batch of cast trial impellers."

Since Chief Li asked, Yang Hui answered frankly—there was nothing confidential.

But Chief Li was still puzzled; when had impellers become so heavy, needing a box for transport?

He watched Yang Hui and the young man carry the box inside and grew curious—what kind of impeller was so contrary to expectations? How could an engine part be so heavy?

After setting down the box, they attracted a crowd of researchers, all inspecting the heavy container.

"Come, open the box."

Yang Hui and his team had already opened it once, so it was easy to do so again.

Inside, the neatly arranged castings were disappointing to some; they'd expected something large and impressive, but instead found a bunch of small impellers.

"Are you sure these are for testing, not finished products?"

Seeing so many neatly stacked impellers, Chief Li felt it was too many for test pieces—testing didn't require such a quantity.

He picked up one impeller and said, "This is the trial piece, designed to be simple and easy to manufacture, so seventeen out of twenty succeeded."

Hearing that the impeller was so simple and succeeded on the first try piqued Chief Li's interest. If such a simple design could meet the requirements, it was remarkable—turbojet engines demand high compression efficiency, and their impellers are usually complex. He knew not to mistake simplicity for ease; the difference was vast.

He picked up an impeller, brushed off some ash from the blades, and examined it closely. There was nothing particularly special about it, except for its simplicity.

"It's strange—are you sure your calculations will work?" He got straight to the point.

"Chief Li, the calculations are based on experience, but whether it works depends on your test results." Calculations alone couldn't yield precise values—impeller efficiency was always estimated from experience, but empirical formulas were unreliable; testing was essential.

"Very well, let's test it. I'm curious to see what efficiency this ordinary-looking impeller can achieve."

While speaking, he counted the impellers, calculating how many were needed for testing. All couldn't be used—too wasteful.

"Jian, hand over the test project list for Chief Li's records." Hearing Chief Li was ready to start, Yang Hui quickly told Zhong Jian to produce the list.

"Alright, give it to me. Come sign with me." Chief Li checked the test items on the list, then led Yang Hui and Zhong Jian into the office.