Proof +19
Director Seo’s question was downright aggressive.
It was no different from picking a fight and telling me to come at him for real.
But instead of taking offense, I let my gaze drift back to the video I’d just watched and answered in a calm tone.
I could understand why he was acting like this, after all.
“You said this was a zone where aerodynamic formulas were useless. But the way heated metal warps is the same no matter what field you’re in.”
“Metal is metal, sure. But aerodynamics is a whole different—”
“Would you mind hearing me out before you speak?”
I cut Director Seo off.
He frowned, clearly irritated, but didn’t say anything else.
It was as if he wanted to see where I was going with this.
“From the materials your team submitted, once the missile breaks past Mach 5, the plasma’s superheated temperatures begin traveling through the outer shell and into the titanium frame inside. The fuel injection nozzle, unable to withstand the thermal expansion, twists by a microscopic amount.”
I could see it.
The missile casing blazing red-hot, the heat seeping inward along the titanium frame, and the fuel injection nozzle warping by the tiniest fraction in that miserable little cascade of failure.
“The nozzle angle shifts by 0.2 degrees because of the heat, and as a result, shock waves reverse inside the combustion chamber and kill the engine. It doesn’t look like a materials limit to me. It looks like a mechanical design flaw that failed to account for thermal expansion.”
“......!”
“If you wrap the fuel line around the outer shell one more time, I think you can solve it. Change the flow path so the cold liquid fuel absorbs the heat from the outer casing first, acting like coolant before it enters the combustion chamber. That should prevent ablation and improve combustion efficiency too.”
When I finished, a few people gave dry, disbelieving laughs.
But just as many stared at me as if they were questioning their own ears.
Some of them understood exactly what that meant technically; others, not being in a field that overlapped with it, simply couldn’t.
And the arrogance drained from Director Seo’s face like water from a sink.
He looked back and forth between the report in front of him and my face, dumbfounded.
“S-So if you do that... it’ll work?”
His voice cracked embarrassingly.
But in that brief moment, it was obvious that countless variables were already being calculated in his head.
He shut his eyes tight, thinking for a few seconds, then opened them again and said cautiously, “But, Director Baek. The regenerative cooling method you just mentioned is something we also considered. The problem is... this is frictional heat at Mach 5. If the fuel absorbs heat while traveling along the casing, it’ll boil and vaporize before it even reaches the combustion chamber. Wouldn’t that stop the engine?”
Well, yes.
It wasn’t as if I understood hypersonic thermodynamics or aerospace engine structures perfectly myself.
But when I mixed what I’d seen in that video with fifteen years’ worth of mechanical engineering instincts, it was a very simple problem.
“Well, I’m not especially well-versed in hypersonics.”
I gave an awkward smile and continued.
“But looking at the drawings, there’s a bit of pressure margin in the fuel pump. If the issue is the fuel boiling, wouldn’t it be enough to raise the injection pressure by about 1.2 bar? That should raise the boiling point, so it won’t vaporize and should stay liquid as it’s forced in.”
“......!”
“That’s a common fix when you’re dealing with engine overheating in tanks or working with high-pressure hydraulics. Shouldn’t it work there too?”
“Hah, ha ha... So all we needed was a change in perspective, and we’ve been—”
Director Seo muttered in a daze.
If I’d been in his shoes, I probably would’ve felt the same.
Something you’d spent years killing yourself over, never finding even the faintest clue, and then somebody glances at the paperwork once and says that’s the answer?
You’d be thrilled that the research could finally move forward, sure. But at the same time, you might also feel your motivation as a researcher collapse under the weight of a wall so absurdly huge it barely seemed real.
But that was his burden to carry.
It wasn’t my job to worry that far for him.
Thinking that, I shifted my gaze around the room.
By then, the atmosphere in the conference room had completely reversed.
Even those who hadn’t properly understood what I’d said were now looking at me with expressions that said they’d realized something from Director Seo’s reaction.
At that moment, someone cleared their throat carefully and spoke.
“Director Baek. May I ask you a question?”
It was Yoo Byungho, the team leader in charge of the Next-Gen APFSDS development project for piercing ultra-high-hardness composite armor.
He was looking at me with a face that mixed hope and anxiety in equal measure.
“Yes, Team Leader. What is it?”
“Could there be a clue for our project too? We still can’t find the cause of the round veering off course right after leaving the barrel. In simulation, the sabot separation timing is perfect, but in live fire the penetrator’s axis twists however it wants.”
Instead of answering, I slowly lowered my eyes.
Earlier, when the meeting began, Senior Vice President Kang had placed a stack of fourteen summary reports on the table in front of me.
I picked up the one belonging to Yoo’s department, the Next-Gen APFSDS Development TF, and opened it.
[Prototype Name: K-APFSDS / Muzzle Velocity: 1,800 m/s / Sabot Separation Error: Within 0.002 sec (Normal) / Issue: Asymmetric yawing occurs when entering air resistance. Cause unknown.]
Their limitation had been recorded in dry numbers in the summary section.
Even after running tens of thousands of simulations, it always came back with zero error, yet the moment they actually fired it, it went off course—a miserable record of failure.
Without thinking, I turned to the next page, where a 3D assembly drawing showed the sabot and penetrator interlocking together.
Vwoom—
The complex equations drawn across the diagram in front of me vanished, and the inside of the barrel rose vividly before my eyes like a live image.
The instant the round accelerated to 1,800 meters per second.
I could see the flow of force moving through that massive lump of machinery.
Under normal conditions, the propellant’s force should have dispersed smoothly through the entire round.
But now, at the dovetail joint where the aluminum sabot and tungsten penetrator meshed together, crimson stress was concentrating like a swollen blood vessel about to burst.
So that was the problem.
The sabot’s teeth, unable to endure the 60,000 G acceleration and the searing heat, had lost their shape in an instant and collapsed.
The boundary between the two metals had fused under pressure, as though they’d been welded into one.
Then, just as the sabot exited the muzzle and met air resistance, the teeth that had fused together were torn free with violent force, spitting out huge red sparks like a frenzy.
If one side came loose that late, dragging the shock wave with it, the trajectory would be thrown off. It had no choice but to.
Roused from the ringing in my ears, I looked straight at Team Leader Yoo and answered at once.
“Team Leader. I’m sure you accounted for thermal expansion between different materials. But the tooth engagement angle in the drawing is only calculated for a static state, isn’t it?”
“...What do you mean?”
“When you’re hit with a shock wave of 60,000 G accelerating at Mach 5, along with superhigh heat, the aluminum tooth surfaces fuse.”
“Fuse...?”
“Yes. Not simple expansion. I mean the pressure is so extreme that the metals momentarily melt and weld together. That’s why the separation timing gets delayed as if it’s being torn free. You’ll never see that in a drawing or a conventional simulation.”
Team Leader Yoo’s mouth fell open.
That was a nonlinear blind spot even a computer couldn’t calculate, something you’d never know unless you physically dissected the fragments under a microscope.
No wonder he was shocked when I brought it up.
And once he realized it was plausible from my explanation, that surprise must have deepened even more.
“Hm. Excellent.”
Chairman Jo, who had been watching me talk with the others gathered here, spoke from the side.
He looked at me with obvious satisfaction and went on in a low voice.
“Director Baek. I dropped you in among these bastards without giving you a single sheet of prep material, so you must’ve been thrown off balance. Yet you survived beautifully.”
“Ha... haha. You’re too kind, Chairman.”
“Let me be honest. I thought you’d pass if you at least kept your nerves and grabbed one or two of them by the collar in this room. I wanted to see whether the guts and instinct you used when you were tearing into the Khanck bastards with ground equipment would still work here.”
Chairman Jo’s eyes burned.
He looked as though he’d just discovered a very useful weapon, and pure delight flickered in his gaze.
“But to think you’d look at the drawings from your seat and strip all the hot air right out of these so-called experts. You’re a madman, far beyond what I expected. I like you. Very much.”
He set down his teacup and swept his gaze over the still-frozen department heads.
“And you lot. Just a moment ago, you were practically baring your teeth at Director Baek, with no thought for my face at all. So, did you enjoy yourselves?”
“I-I’m sorry, Chairman.”
“It wasn’t like that...”
Only belatedly realizing what they’d done, they began scrambling for excuses.
Chairman Jo gave a snort and lifted a hand, as if to say it was enough.
“I left you to it because I wanted you to talk technology. An engineer’s arrogance should be beaten down by even more overwhelming engineering—that’s only proper. So, then. What do you think now? Does anyone still have a problem with Director Baek?”
The conference room was swallowed by dead silence.
Chairman Jo had set the whole board up as a stage to test me, and as a giant trap to rein in the elite who’d grown complacent in their own arrogance.
Having settled the matter with a few words, he nodded in satisfaction and spoke again.
“All right, Director Baek. It seems you’ve earned everything you came here to earn, so let’s make a decision.”
“A decision, sir?”
“Yes. I told you to choose where you’d like to go first, didn’t I?”
At the chairman’s words, the conference room went utterly still.
All fourteen elite department heads held their breath, staring only at my lips.
I slowly swept my gaze around the room.
Not long ago, these were the same people glaring at me like they wanted me dead.
But now their eyes had changed, and they were hoping, desperately, that I’d come work with them.
Honestly, at this point I’d be fine with medium torpedoes or hypersonic missiles.
If I went there, I’d be welcomed as a VIP, and the work would be incredibly easy.
But this was the moment to prove myself.
Talking with my mouth alone wasn’t enough.
If I wanted to smash the financial line that controlled the company with numbers, I’d need to hand the chairman a result so overwhelming it would overturn those numbers too.
If I could prove that I was the fixer who could drive results anywhere, the chairman would be more than willing to dance with a knife behind my back.
Then—
If I wanted to make a decisive statement outside the ground-equipment division as well, I’d need to take on something truly considered impossible.
“I think I’ll...”
My gaze moved to a corner of the table.
To the man who’d been shrinking in on himself from the start of the meeting, glancing around nervously, his face worn by the pressure of failure.
Director Yoon Taeseok, head of the Multi-legged Walking Combat Robot Lab.
That place was an even deeper hell than Manager Maeng’s TF.
The company’s smartest elites were assigned there, but after years of robots that still couldn’t walk properly, it had become known as a dead-end posting in all but name.
A place so cursed that every elite sent there started browsing job sites first.
I looked him dead in the eye and spoke.
“The Multi-legged Walking Robot Lab. I’ll start there.”
“W-We...?”
Director Yoon, who had just made eye contact with me, jolted in shock and his shoulders trembled.
He looked flustered, as if wondering why it had to be his team of all people, yet at the same time it was obvious he was also hoping that if I worked with them, maybe I could make their research succeed.
Maybe that was why Chairman Jo burst out laughing, clearly delighted and intrigued.
“Hahaha! Good. Very good. Starting tomorrow, report there right away.”
Not long after Chairman Jo said that, the tense meeting came to an end.
The people leaving the room wore heavy steps, swallowing their disappointment.
As I watched their backs, Senior Vice President Kang quietly approached my side.
“Director Baek.”
“Yes, Senior Vice President.”
“As you know, the current Technical Audit Team consists of only you. While you’re working with the robot lab, take your time and find the people who’ll fit with you in the audit team. There’s no need to rush. You can look slowly.”
It was authority over team building.
I quietly nodded.
A new beginning in the company’s graveyard, and a real team I would build with my own hands.
More than fear, a pleasant excitement was rising in me.