Changkong Fighter

Chapter 115 Attack from the bottom of the sea!
The towed sonar array is far away from the stern of the submarine and is less affected by its own noise. It can detect underwater submarines at a farther distance. When sailing at a speed of 6 knots in the deep sea, the detection range is within tens of nautical miles. However, this sonar array will now affect the submarine's tactical maneuvers.

The Long March 18 gently folded up its towed sonar array, just like holding the finest silk, gently and softly holding it in its arms.

After the towed sonar array was completely retracted, the shaftless pump thruster drove the propeller to rotate at a low speed, and the huge black fish slowly moved and turned into a favorable position for the unidentified submarine.

"Report to the captain! The target is unstable. The sonar is intensifying the search!" The sonar officer listened and reported in a low voice.

"Increase bow sector search!"

"Yes! Strengthen the bow sector search!" The sonar officer adjusted the sonar.

"Target bearing, 138 tracking unstable."

"Target bearing, 130 tracking unstable."

Time passed minute by minute. Every once in a while, the sonar officer would report the unknown submarine's location to the captain and the first mate. However, even though the Long March 18 was equipped with a powerful air conditioner, the crew still felt cold sweat constantly coming out of their foreheads.

Underwater combat is different from combat on the surface and in the air. When a surface ship is hit or a fighter jet is hit by a missile, the pilot has a chance of survival. However, underwater, if a submarine is hit by a torpedo, the probability of survival for the crew is infinitely close to zero!

Drops of sweat poured out, gathered together, and flowed down the sonar officer's forehead.

The technician beside him carefully took out a tissue and wiped it for him. Now, the person with the most pressure on the whole boat is the old squad leader!
The sonar officer operated the phased array sonar system on the Long March 18 to scan the area where the unidentified submarine was located.

"Report to the captain! Target detected at position 019! Stable tracking possible!"

After hearing the sonar officer's report, he clearly felt relieved. The Long March 18 successfully entered the 20° sonar blind spot at the stern of the other boat. In other words, as long as the other party did not change its course, its sonar system would not be able to detect the Long March 18.

The captain took a look at the sonar and saw the depth difference with the unknown sound source. The key is not that the greater the depth, the better. The key is that the sonar transducer should be at a depth that is favorable for detecting enemy submarines. Submarine attack is to narrow the depth difference, and now they are at the same depth as the target.

"Yes! Position 019, target number one! Attack and defense teams prepare!" the captain said in a low voice.

"Launch tubes 1 and 2 are ready!" the fire controller whispered. The prepared torpedoes do not need to be filled with water and can be launched directly when needed. It is more secretive and has a faster response speed.

After listening to the fire controller's report, the captain felt that it was not safe enough and issued a new order: "Yes! Load decoy torpedoes into torpedo tubes 3 and 4!"

"Yes! Load decoy torpedoes into torpedo tubes 3 and 4!"

In the torpedo compartment of the Long March 18, the crew began to load the corresponding torpedoes according to the captain's instructions.

While loading the torpedoes, the captain looked again at the first mate and the political commissar standing behind the sonar officer.

"Now, what do you think?"

Hearing this, the political commissar came over and the three of them discussed in a low voice.

"According to the instructions from our superiors, the mission of our boat is anti-access/area denial. Even though our superiors have clearly explained the situation to the international community, this boat still insists on going its own way. My opinion is: sink it!" The captain's voice was like the water in a cold pond, icy and emotionless.

"I agree to sink the other side."

After a moment's reflection, the political commissar agreed with the first officer's opinion. Different situations require different approaches. Now that aliens have appeared, the situation has changed. Who knows what this lurking submarine will do? What if, after shooting down the alien spacecraft, it launches a torpedo at the containment ship? Wouldn't that be a waste of time? Don't underestimate human nature. Because the success of the East China University of Science and Technology in containing the aliens may make it the first country to communicate with an alien entity, some people naturally don't want to see it happen. Letting the aliens die at the hands of the East China University of Science and Technology is in the interests of some people.

The first mate looked at the two men and nodded: "I agree to sink it too."

The three highest-ranking officers on the boat had already reached a consensus, and with the instructions sent in advance by their superiors, the captain no longer hesitated:
"Yes! Fire control officer, calculate all the parameters."

"Yes, calculate all the elements!"

Upon hearing the order from his superiors, the fire control officer immediately began to calculate the movement elements of the submarine in front.

Hull sonar is the main sonar detection equipment of submarines. It works passively and receives the propeller noise emitted by the target to confirm its existence. It can only determine the target range but not the target distance.

After the Long March 18 can stably track the target, the fire control computer continuously processes the sonar data and calculates the target direction detection data after more than four times. Combined with the submarine's tactical maneuvers, the computer finally calculates the target's course, speed, direction, distance and other motion factors.
"Captain, target distance 19000! Bearing 017, speed 10 knots. All inputs complete!"

"Yes! Launch tubes 1 and 2 ready!"

"Yes! Launch tubes 1 and 2 ready!"

Inside the launch tube, the system began to balance the water pressure inside and outside the launch tube. After the pressure was balanced, the fire control officer looked at the captain.

"Yes! Launch tube No. 1 launches electric torpedoes! Launch tube No. 2 launches thermal torpedoes!"

"Yes! Launch tube No. 1, launch the electric torpedo! Launch tube No. 2, launch the thermal torpedo!"

In launch tube No. 1, without the impact of the hydraulic tank, the self-propelled electric torpedo silently sailed out of the launch tube. Under the power of the torpedo itself, the electric torpedo approached the submarine in front at a speed of 40 knots.

The thermal mine in the No. 2 launch tube is much more violent than the electric mine. It is "catapulted" under the impact of the pulse water tank and speeds across the seabed at a violent speed of 50 knots.

The two wire-guided torpedoes are connected to the submarine's fire control system, making it easier to control them and also easier to self-destruct in special circumstances.

Click. At the moment of launching the torpedo, the captain looked at the distance between the two sides and pressed the timer in front of him.

It takes about 40 minutes for an electric mine to travel 18000 meters at 15 knots, while a thermal mine only takes less than 12 minutes, leaving the opponent with very little time to react.

After watching the torpedo launch and confirming that the hydroacoustic gradient layer was positive, the captain issued new orders.

"Yes! Bow tilt 10 degrees, set depth 240, enter the positive gradient layer."

After launching a torpedo, in order to prevent possible counterattacks from the submarine in front, it is necessary to conceal itself more. Increasing the depth difference and taking advantage of the hydrological environment are the best ways to conceal itself.

"Yes! Bow tilt 10 degrees, set depth 240, enter the positive gradient layer."

The first mate continued to repeat the order to confirm that it was correct, and the helmsman adjusted the depth of the submarine according to the captain's order.

The Long March 18's elevator adjusted its angle, and the big black fish slowly dived into the deep sea. The black hull was hidden from the translucent layer, and finally disappeared under the deep sea and entered the aphotic layer.

(End of this chapter)