The Desert Ghost
Three days later, in Riyadh, Saudi Arabia.
The instant the automatic doors of King Khalid International Airport slid open, I nearly stumbled backward on instinct.
Whoosh—
It was like someone had pointed a giant hair dryer straight at my face and turned it on full blast.
48 degrees Celsius.
It was a dry, murderous wind that belonged to a different world from Korea’s humid heat, the kind that seemed determined to strip the moisture from your skin in an instant.
My breath caught in my throat.
Frowning, I yanked my tie loose with a rough tug.
The cool air-conditioning I had been enjoying in first class only a few minutes ago suddenly felt like a memory I could never have again.
As I passed through the arrivals gate, unfamiliar Arabic announcements and the low roar of the crowd crashed into my ears all at once.
Still, I tightened my grip on my carry-on and pushed my way through the people toward the exit.
That was when the automatic doors opened again and the raw, unfiltered heat hit me square in the chest.
“Department Head Baek Gunwoo! Over here!”
A man in a crisp suit waved at me.
It was Choi Gyeonghun, a deputy general manager dispatched from headquarters’ finance team.
He was one of Yoon Taejin’s key people, and the one monitoring the budget for this project.
“You must’ve had a rough trip. The weather’s vicious, isn’t it?”
“It sure is. I feel like my throat’s drying out just from breathing.”
“Come on, get in. I’ve got the air-conditioner cranked all the way up.”
Choi Gyeonghun opened the door of the black SUV waiting at the curb.
The cold air wrapped around me the moment I got in, but the things coming out of his mouth were every bit as suffocating as the heat outside.
“You’ve heard the rough situation already, right, Department Head? It’s a headache.”
“Yes. At least in broad strokes.”
Chairman Cho had only told me to go to Saudi Arabia and help his daughter save face.
But this was clearly not the kind of matter you could reduce to something that simple.
Was the first-class ticket and the extra 2.7 billion won supposed to be payment for dealing with this mess?
As that thought crossed my mind, Choi Gyeonghun kept talking.
“The first fifteen units were delivered, and the balance was settled too. But the Saudi military is finding fault with us now. They’re refusing to sign off on the follow-up contract, claiming the APS keeps malfunctioning.”
“What’s the on-site assessment?”
“Honestly? There’s nothing to assess. They’re just trying to squeeze the price down.” Choi snorted. “We tested those machines hundreds of times at the Yangpyeong facility in Korea and they passed every one. The mil-spec requirements were met perfectly, and since this was a big-ticket order, finance only sent out genuine top-grade parts. So a breakdown? It doesn’t make sense.”
“······”
“The local operators just don’t know how to handle it. They’re trying to pin it on our equipment and negotiate the price down, and Director Cho Yerin is swallowing it all like a fool.”
He praised the finance line’s integrity while subtly shifting the blame onto Cho Yerin, the person in charge on the ground.
There it was—the familiar flavor of corporate politics. I gave a vague nod and turned my gaze out the window.
Endless red sand dunes, with heat haze rippling over them.
It was a scorched wasteland with not a trace of life to be found.
Well, live long enough and everything happens.
Even a trip like this ends up becoming part of your work.
While I was thinking that, Choi Gyeonghun’s voice kept going.
“Director Cho’s been a little too ambitious. Maybe because she’s the chairman’s daughter, but she doesn’t know how to compromise and keeps blaming headquarters, blaming the machine... Honestly, Department Head, you need to go in there and shut it down. Tell her plainly that this isn’t a hardware defect—it’s operator error.”
Operator error, huh...
That was a mouthful.
I looked back out at the desert.
Machines don’t lie.
It’s always people who do.
Whether it’s the one trying to save money or the one trying to dodge responsibility.
“Let’s go take a look. We’ll see whether the machine’s gone mad or the people are incompetent.”
◇◇◇◆◇◇◇
Two hours by car from downtown Riyadh.
King Khalid, a self-sufficient military city, and the nearby Hanseo Defense MRO Center were a field base made up of massive tents and shipping containers.
The moment I stepped out of the vehicle, hot wind mixed with sand slapped my cheeks.
Spitting grit from my mouth, I headed for the operations container.
Just as I reached for the handle, a shout burst from inside.
“I swear by the name of Allah, your tank is a blind man with its eyes open!”
A Saudi officer with a thick mustache was yelling in English.
In front of him stood Director Cho Yerin, dressed in work clothes and smeared with grease, looking deeply troubled.
“Colonel, according to the data there’s no sensor error. If you’d only give us a few more days, we can identify the cause...”
“Days? I already gave you two weeks! You expect me to put my men on top of a pile of scrap metal like this? If it isn’t fixed by tomorrow, I’ll demand a full recall and terminate the contract! Do you understand me?”
The Saudi colonel huffed out of the container in a rage.
He met me at the doorway, raked me over with a hostile glance, then spat on the ground and climbed into a jeep.
Damn, he’s fierce...
I clicked my tongue and stepped into the container.
Cho Yerin ran a hand through her disheveled hair and let out a sigh.
Dark circles hung beneath her exhausted eyes, all the way down to her cheeks.
“...Assistant Manager? It’s been a long time.”
“It has, Director.”
Cho Yerin, still in her work clothes, gave a bitter smile.
Her brown hair was tied up tightly, and the white nape of her neck was damp with sweat.
With her sharp nose and stubborn, catlike eyes, she looked as if she had been dragged through desert dust and hadn’t managed a proper wash in days. And yet, because she was so striking to begin with, the grime somehow made her seem even fiercer.
She looked exactly the way she had eight years ago, back when she was a new hire glaring at me with venom in her eyes every time I tore up one of her drawings.
“You must’ve had a rough time getting here from Korea. Was the flight comfortable?”
“Well, thanks to you.”
It had been first class.
There was no way it hadn’t been comfortable.
I shrugged lightly and said, “I’m not sure I should say this, but you look like you’ve really been through it. This is worse than when you used to get hounded by me eight years ago.”
“······”
Cho Yerin’s eyebrow twitched.
It was a strange expression, part embarrassment, part relief, part lingering hurt. Then she snorted and shot back, “Honestly, Assistant Manager... no, wait, I can just call you Senior, right?”
“Considering my rank now, wouldn’t it be more appropriate to call me Department Head Baek?”
“You’re my old senior. How could I do that? This isn’t Korea, where everything runs so stiffly. I’m calling you Senior, so just accept it.”
That was what she said.
I could only laugh and nod.
It felt nice to think that a junior I hadn’t seen in years still thought well of me.
“Suit yourself.”
“Yes. Anyway, I got yelled at by you in the past, and I really did work my ass off after that. I haven’t forgotten you tearing up my drawings either.”
“Ha, haha... I’d really prefer it if you could forget that part.”
“Right now, I need that version of you—the senior who got angry while ripping apart my drawings. I can’t tell what the problem is, no matter how hard I look. Will you take a look?”
“Yes. Let’s see it first.”
I set my bag down and walked up to the monitor.
Raw data from the APS radar scrolled across the screen.
The input voltage held a clean 24V DC without the slightest fluctuation, and there wasn’t a single spike of noise in the power waveform.
The cooling system was the same.
Even with the outside temperature at 50 degrees, the core temperature inside stayed frozen at 85 degrees without budging.
There was no way throttling could kick in, and the software hash values matched the certified originals on headquarters’ servers.
It was suspiciously immaculate data, the kind you’d expect from a compulsive neat freak.
“It’s perfect.”
At my words, Cho Yerin lowered her head.
“Right? It’s driving me insane. It matches the Korean specs perfectly. Like finance said, every part is genuine, and our maintenance crew checked every wire one by one all night.”
“And yet it dies in the field?”
“Yes. Once they start the engine and get moving, ten minutes later a ghost appears on the radar. An alarm goes off saying missiles that don’t exist are incoming.”
Ghost, huh.
I folded my arms and glared at the monitor.
The data was screaming that the machine was fine, while reality insisted it malfunctioned?
Choi Gyeonghun, who had been watching my reaction, seized the moment to jump in.
“See, Director? I told you the machine’s perfectly fine. This is just the sensor misreading desert mirages or heat haze. It’s a temporary error caused by the environment. Just submit a report saying so. If we lower the sensor sensitivity, the problem should go away.”
“Lower the sensitivity?”
I turned and shot him a look.
“So when a real missile comes in, what then? I suppose you’ll be collecting condolence wreaths instead of penalties.”
“No, I mean we have to close the contract now...”
That was how accidents happened—forcing things forward while staring only at the money.
The first or second time, maybe you could get away with it without any major disaster.
But once one became two and two became three, the risk grew exponentially.
I ignored Choi Gyeonghun and stood up.
“We won’t get an answer just by staring at monitors here. I need to hear from the people actually driving this hunk of metal.”
“You mean the operators? They don’t even make any sense. All they do is complain that it’s too hot.”
“The people you’re calling complainers are our customers, Deputy General Manager.”
Seriously. Unbelievable.
I frowned and said it flatly.
Choi Gyeonghun looked embarrassed and averted his eyes from mine.
◇◇◇◆◇◇◇
One corner of the maintenance hangar.
Three tank crewmen in Saudi military uniforms were sitting in the shade, smoking a water pipe.
They looked to be barely twenty.
When they saw me, they turned away with irritated expressions, as if they were thinking, Great, another headquarters fossil coming to lecture us.
Then the man seated deepest inside slowly stood up.
He was tall and refined, with an intelligent air about him. The watch visible beneath the rolled sleeve of his uniform was a Patek Philippe—top of the top.
“Excuse me. Are you the Wizard from Korea?”
Fluent British English.
Choi Gyeonghun’s jaw dropped open.
I gave a faint smile and answered in equally fluent English.
“I’m not a wizard, just a mechanic sent to fix what’s broken.”
“A pleasure to meet you. I’m Lieutenant Fahad, tank commander.”
He held out his hand.
Shaking it, I asked him straight out, “Lieutenant, what’s the most annoying thing about driving this tank? If you can be honest, it’ll help a lot.”
Lieutenant Fahad gave a crooked smile.
“Honestly? It’s disappointing. The mobility is excellent, but the electronics are too sensitive. They scream even when there’s nothing there. My men have started to believe it’s an Allah-given curse.”
“Screaming, you say... When does it usually happen? At night? During the day?”
Fahad thought for a moment before answering.
“It’s always the same. It happens when the engine torque rises to its maximum. That’s when the ghost appears.”
Maximum torque.
If this were a simple electronics fault, it shouldn’t have anything to do with engine output.
But he said it only appeared when the engine was working at its roughest, so it wasn’t a power issue...
Something that inevitably came with rising torque.
The engine’s roar, and the vibration shaking the hull.
Something brushed through my mind.
◇◇◇◆◇◇◇
The desert training ground behind the MRO base.
Kuuuuung—!
The 1,500-horsepower engine exhaled a rough breath as the tank began to move.
The tracks churned up sand and sent the vehicle racing across the desert.
Inside the turret were me, Cho Yerin, and Lieutenant Fahad.
“Pick up the speed! Drop the gear and push the RPM all the way to the limit!”
At my order, Lieutenant Fahad relayed the command to the driver.
Kwaaaaang—!
The tank brutally climbed a sand dune.
Thanks to that, the engine tachometer needle shot up to just before the red zone.
Feeling a vibration so huge it seemed to pound directly through my chest, I kept scanning the surroundings.
Then, all at once—
Beep— beep— beep—!
The APS alarm shrieked.
Cho Yerin shouted in alarm, “Ghost targets! Twelve o’clock, two o’clock, nine o’clock—multiple contacts approaching!”
“Damn it. There it is again.”
Lieutenant Fahad grimaced.
On the monitor, dozens of scarlet dots were swarming toward the tank.
I barked, “Do not stop! Keep the RPM steady! Don’t let the torque drop!”
Rather than watching the sensor monitor, I concentrated all my attention on the source of the vibration, staring toward the APS module at the rear of the turret.
The heavy vibration waves from the 1,500-horsepower engine.
They were striking the hull in a steady rhythm.
Thud, thud, thud.
It was a normal blue wave.
But the instant that wave reached the sensor support frame—
Kwaaaang—!
The small wave suddenly turned into a massive red tidal surge.
The frame wasn’t merely passing the external vibration along; it was swallowing the energy whole and swelling larger with it.
The timing was the worst possible.
The rhythm of the engine hitting its stride and the rhythm of the frame shaking lined up with chilling precision.
Like pushing a swing, the engine’s vibration kept shoving the frame from behind.
No wonder a perfectly normal steel support was flailing like a mad thing.
“...Found it.”
This wasn’t the fault of a part.
It was just bad luck.
Because the two rhythms happened to match with horrifying precision.
“I found it. Let’s stop for a moment.”
“What?”
“Stop it for a second!”
At my shout, Lieutenant Fahad began to slow the tank.
As the engine RPM dropped and the vibration subsided, the alarm stopped as if nothing had ever happened.
I opened the hatch and climbed outside.
Cho Yerin and Lieutenant Fahad followed with puzzled expressions.
I opened the cover of the APS module at the rear of the tank and placed my hand on the frame, which was still trembling faintly.
Jiiiiiiing—
An unpleasant high-frequency vibration ran through my fingertips.
“What is that? Why are you doing that?”
Cho Yerin asked.
“When the engine applies power, the vibration it produces matches the frame’s natural frequency. By sheer coincidence, the two of them were in perfect rhythm and dancing together.”
I tapped the frame, which was still humming softly.
“You said earlier that the ghost only appears when the engine is running at full blast, right?”
“Yes. You said it only happened when torque was turned all the way up.”
“That was the key piece of evidence.”
I counted off on my fingers as I explained.
“If it were a sensor defect, the error would’ve appeared the moment the engine started. If it were just overheating, slowing down wouldn’t have shut it off immediately. And if it were only a vibration problem, the shaking should have increased proportionally as speed rose.”
“Uh... then...”
Cho Yerin’s eyes began to widen little by little.
I nodded and went on.
“This thing was fine until it hit a specific RPM, then suddenly had a seizure. The moment it dropped out of that range, it stopped as if nothing had happened. By now, it’s obvious.”
“...A physical amplification that only responds at a specific frequency.”
“Yes. Resonance.”
“...I’m going to lose my mind.”
Cho Yerin muttered in disbelief and raked a hand through her hair.
She was staring at me with a face that said she couldn’t possibly understand how this had happened.
“Wait. You just went for one drive and figured that out?”
“Haha... I guess my instincts got a little better.”
“Is that what you call having good instincts? You’ve turned into a complete... monster.”
“A monster? That’s a little much. This is just field experience.”
I brushed it off with an easy grin.
But Lieutenant Fahad still looked grave.
“Resonance? Does that mean there’s a structural defect?”
“Strictly speaking, yes. The design failed to account for the desert environment and the engine load at the same time.”
“Ha...”
Cho Yerin let out a deep sigh and collapsed into a squat.
“Then we have to redesign it! Change the frame thickness, change the material, shift the natural frequency somehow... how are we supposed to do that here? Even if we ran simulations again at headquarters in Korea, it would take at least a month!”
It was a hopeless situation.
With the contract possibly being scrapped tomorrow, they were being told to redesign the structure from the ground up.
Cho Yerin looked like she was on the verge of tears.
“Who said we’re redesigning it?”
“What? Then what do we do? The frequencies overlap.”
“We can’t change the design, but we can change the rhythm.”
“The rhythm?”
“Let’s do this the quick-and-dirty way. If we can tame this vibration, this thing’s eyes will open a lot wider.”
“...Quick-and-dirty?”
“Yeah. Quick-and-dirty.”
I grinned.
Cho Yerin stared at me as if a giant question mark had materialized over her head.