21st century Goguryeo

June 30, 2020, 16:00

N 36°10' E 125°10,' 12.7 km away from Korean waters

The Romeo-class SSK-315 submarine that departed from the Ching-dao naval base stopped its engines 12.7 km away from Korea's ocean border, then transitioned into silent voyage mode while submerging to a depth of 40 m.

"We now silently voyage, resting until the next order."

Under the captain of the submarine's orders, the 40 crew members all fell silent and took their break, making as little noise as possible.

"Submarine changed to silent mode. All rest in silence until the next order." The controller of the submarine relayed the captain's orders, then put down his microphone and rested silently like the rest of the crew.

The reason why they had gone silent under international waters, 12.7 km away from Korean waters, was a mystery.

* * *

June 30, 2020, 16:00

OSCAR Bunker, Daegu-si (Undersea Defense Satellite KS-SD Poseidon 2 Mission Control)

"Chinese submarine now at N 36°10' E 125°10' depth 40, and gone silent."

Puzzled by the sonar operator's report, Commander Lee Eun-soo looked at the operation controller as if he expected an answer from him.

"I'm sorry, sir," the operation controller said. "I also can't predict their intentions."

"Man, that old metal piece of junk is getting on my nerves. If we were unaware, then that would be a different story. But since we know their every move but not their intentions, it feels as if we were bitten by a mosquito in a place our hands can't reach."

"Commander, your expression is top-notch."

"Ha ha, is that so? Anyhow, since things are the way they are, have all men on watch tonight keep a close eye on that old hunk of metal. And if anything suspicious comes up, tell them to report to me immediately."

"Understood, Commander."

"Contact the Coastguard and restrict the movement of our fishing ships in this area. If something happens, that would be a major headache."

"Yes, I understand."

* * *

July 1, 2020, 04:00

OSCAR Bunker, Daegu-si (Undersea Defense Satellite KS-SD Posiden 2 Mission Control)

After receiving a call at 4:00 a.m. from the sentry officer of Poseidon 2, Commander Lee Eun-soo rushed over to the bunker, where Captain Na Gang-soo was making a brief report.

"The Chinese submarine is at N 36°10' E 125°10' depth 40, silent and stationary, no other changes."

"That means nothing changed since I left yesterday, doesn't it?"

"Please have a look at the screen, sir."

At the sentry officer's command, a map of Korea's West Sea appeared on the commander's screen. A ship 70 km away from the position of the submarine they were monitoring was heading north at a speed of 17 knots.

"What's that ship?"

"Its nation of origin is North Korea. It's the 120,000t oil tanker, the Pyeong yang 2."

"A North Korean oil tanker?"

"Exactly, sir."

Commander Lee Eun-soo took a closer look at the line indicating the Pyeong yang 2's expected route. The oil tanker would head north through international waters, and then reach its final destination in Nampo port. But what shocked Commander Lee Eun-soo was the fact that the oil tanker's route was very close to the Chinese submarine that had gone silent in the middle of the route, 40 m under the sea.

"Could the Chinese be trying to pull something to the North Korean oil tanker?" the commander asked.

"Commander, this was why I had urgently called you," the sentry officer said, full of doubt. "Our superiors are under the assumption that China will not only use economic attacks but also military attacks."

"Right. The situation is too dire to just dismiss it as a 'what if.' If they fire a few torpedoes at the North Korean oil tanker and leave, then South Korea would be held under suspicion, wouldn't it? This could also derail South and North Korea's relationship. This was good judgment on your call, Sentry Officer. I will take the command from you now."

"Understood, Commander."

"Good. Men, what we do from now on is very important. Please stay focused despite your fatigue."

"Yes, sir."

Commander Lee Eun-soo sat in his personal chair and gave orders while looking at the center screen.

"Check for ships within a 50 km radius of the Chinese submarine."

"None."

"Sonar Operator, put the sonar range at maximum output, and focus on scanning."

"Yes, sir."

"Torpedo Operator?"

"Yes, sir."

"Target Romeo-class SSK-315 submarine. Supercavitating Rocket Torpedo 'Trident' lock-on and standby."

"Supercavitating Rocket Torpedo lock-on and standby." The torpedo operator repeated the order while operating the console to put the torpedo on standby.

"Sonar Operator, calculate distance and time to reach the submarine after launch."

"Distance 54 km and time 158.8 seconds to contact."

"Confirm time based on the North Korean oil tanker's route and the shortest distance for the Chinese sub to launch torpedoes."

"Shortest distance at 2.76 km, and error of 2 seconds for 163 seconds for contact."

"There's a 35-second difference. That's cutting it way too close. Even if we do strike them down, if the torpedo explodes near the oil tanker..."

"That's right. Sir, after the Chinese fire torpedoes, it might be too late to attack. In order to conserve even a single second of time, we must strike first when the Chinese submarine opens their launch pads." Captain Na Gang-won offered this solution, which would be the best choice given the current situation.

"We have no other choice but to follow Captain Na's suggestion, since we must make every second count."

"How about requesting aid from the Western Fleet, Commander?" the operating control director said. He had just arrived and had been standing behind Major Oh Dong-gyu, silently listening to the conversation.

"No, that isn't wise. The Chinese submarine is close to our seas, but they're still in international waters. If our own ships were sent out and got caught in the crossfire, wouldn't that make the situation worse?"

"That is true."

"Yes, let's quietly take care of this ourselves. Honestly, it's not in our jurisdiction to act if the Chinese submarine attacks the North Korean tanker. Right now, we are not in any military agreement with North Korea, are we? If we intervene in such matters, then it will only provide the Chinese with an excuse to act out."

Commander Lee Eun-soo called the communications operator after assessing all possible situations that could take place. "Get the Navy's headquarters on the line."

When the Navy's headquarters was on the line, Commander Lee Eun-soo briefly explained the situation and then put down the wireless microphone.

"It might get boring, but let's all keep our wits about us and take care of this."

Commander Lee Eun-soo had finished making preparations for all possible events. All he had to do now was wait and see.

* * *

July 1, 2020, 06:00

OSCAR Bunker, Daegu-si (Undersea Defense Satellite KS-SD Poseidon 2 Mission Control).

After two hours had passed, North Korea's oil tanker, Pyeong yang 2, approached the Chinese submarine that was waiting silently.

"Pyeong yang 2, now 2.9 km away from the Chinese submarine."

The thirty members in the mission control room of the Posiden 2 all had their gazes fixed on the sonar screen. Their mission hinged on whether or not the launch pads of the silent submarine opened. Because of this, just like the submerged Chinese submarine, the mission control room was silent, save for the few noises and beeps from the digital machines. After a moment, one of the operators shouted, as if to dissolve all the tension in the room.

"Chinese submarine advancing toward the Pyeong yang 2 oil tanker at a speed of 5 knots and rising. They have also opened their launch pads."

Commander Lee Eun-soo hit his knee with his fist. This was something he had missed. He had been stuck on the idea that the Chinese sub would be stationary when they launched their torpedoes, but if the Chinese submarine fired their torpedoes while moving, then the 35 seconds of extra time the Poseidon had bought would be a loss rather than a gain, and this whole mission would be a terrible mistake. However, Commander Lee Eun-soo abandoned these late regrets and instinctively ordered the launch of the torpedoes.

"Fire torpedoes," he said.

"Trident launch successful."

At the commander's order, the torpedo operator fired the Supercavitating Rocket Torpedo, which boasted supersonic speeds, and it rose up from the launchpad. When the torpedo's warhead formed a supercavitation bubble, it reached a speed of 1,224 km/h, which was near the speed of sound, and headed toward the Chinese submarine.

"The Chinese submarine has launched two 533mm torpedoes toward the Pyeong yang 2. Its speed is at 25 knots and rising. The tracking method is wire guidance."

"ETA?"

"142 seconds!"

"ETA of our own torpedo?"

"139 seconds."

Three seconds. It wasn't a lot of time, and it was still too early to feel relieved, but fortunately the Chinese submarine was an old model and only had wire-guided torpedoes on board. If it could be shot down three seconds before its torpedoes reached the oil tanker, then the wire guidance for the Chinese torpedoes would be severed, and the North Korean oil tanker would have a chance to survive.

"Contact the Pyeong yang 2! Order them to make emergency maneuvers to 2-7-0 port side."

At the commander's order, the communications operator contacted the Pyeong yang 2 and relayed the order for them to make emergency portside maneuvers. The Pyeong yang 2 must have also detected the incoming torpedoes, because it accepted the South Korean Navy's orders and turned portside. The oil tanker began to lean to the left and turn.

"20 seconds before Chinese torpedoes reach. Our torpedo is 15 seconds away from contact."

The Pyeong yang 2's emergency maneuver had bought them two seconds, and the commander shook his right fist.

"Striking down the Chinese submarine in 3, 2, 1!"

Booooom.

The operator's voice was full of anxiety and tension as he shouted, "Chinese submarine hit! The wire guidance for the Chinese torpedoes has been severed, but both are still headed toward Pyeong yang 2...."

A moment later, a loud explosion sounded from the stern of the Pyeong yang 2 oil tanker.

Boom, boom.

"Two Chinese torpedoes have exploded."

"The Pyeong yang 2?"

"The Pyeong yang 2 has not been hit. It's safe."

Luck must have been on their side, because the Chinese torpedo exploded two seconds before hitting its target. But it had exploded so close to the ship, the stern took some damages, and one of the propellers broke down. However, it had no issues reaching Nampo port, since its other three screws remained intact. Meanwhile, wreckage of the Chinese submarine began to surface at the location where it had been hit. Among the wreckage were various machine parts marked with Chinese characters, along with the bodies of crew members, which had floated to the surface due to the life jackets they were wearing.

"Request the Navy to send in a salvaging ship to clean up the Chinese submarine's wreckage."

"Commander, the Western Fleet has already sent in rescue choppers and ships."

"All right."

Ten days ago, China had discovered that a North Korean oil tanker, the Pyeong yang 2, was heading from the middle east toward Nampo port. Soon after, they established operation "inferno" and executed their plans. First, they sent two Su-35 fighter jets to the airspace over the Western Sea to vigilantly conduct reconnaissance. The day before the operation was carried out, they sent in the outdated SSK-315 submarine to lurk covertly near Korean waters and the expected route of the oil tanker, then swiftly strike the tanker down and leave.

But China had no knowledge of the undersea defense satellite, Poseidon, deep in the Western sea, which caused their operation 'inferno' to turn into a complete failure. All they managed to achieve was the loss of their submarine and forty crew members aboard. The Korean government immediately sent in a proposal with North Korea to the U.N Security Council, but the proposal did not go through, as China was a permanent member of the UN Security Council.. In response, the South Korean government amended its defense strategy for the West Sea from passive defense to active offense.