. Zhou Yusheng did not intend to attack the North Carolina, but just wanted to leave the detection range of the active attack sonar.

When active sonar is working, it can only emit sound waves to a certain area and search for targets through echoes. If you conduct a large-scale search, you can only scan one by one. To put it vividly, submarines use active sonar, just like holding a flashlight to find enemies in a dark room.

From the perspective of detection range, the detection area of ​​active sonar is a cone with the sonar matrix as the vertex, and the taper is determined by the sonar performance and detection method.

As long as it is not within the search scope of active sonar, the whereabouts will not be exposed.

The attack sonar of the submarine is similar to the fire-controlled radar on the fighter jet, and the sound waves emitted have a certain direction. Although sea water has a divergent effect on the sound waves, the sound waves are divided into main lobes and side lobes, but only when they appear in the main lobes, they will be detected by the attack sonar.

Because side lobes will interfere with sonar and reduce detection distance and accuracy, when designing attack sonars, they will try to concentrate energy on the main lobe and expand the detection range of the main lobe. Some advanced fire control computers will also filter out side lobe signals when processing signals.

The "Virginia" class attack nuclear submarine is no exception. The attack sonar can only detect targets in the main lobe.

Compared with other submarine attack sonars, the performance of bqq-10 is absolutely advanced, much more advanced than the "Sea Wolf"-class bqq-5d, and the detection distance and detection accuracy have reached an amazing height. The key is that bqq-10 greatly reduces the energy of the side lobe through various methods and improves the detection range of the main lobe. When processing signals, the fire control computer can also automatically filter out the side lobe signal.

The Shark is very lucky because it is only eight nautical miles away from the North Carolina, so it does not enter the detection area that attacks the main lobe of the sonar.

But after scanning an area, the North Carolina will definitely continue to scan nearby waters.

The submarine's speed is not fast, and the Shark is in a stationary state. The horizontal maneuvering not only cannot avoid the infrasonic waves that are about to sweep, but will also enter the detection area of ​​the sonar array on the side of the North Carolina. Only by maneuvering longitudinally and approaching the North Carolina can we avoid being detected by the attacked sonar.

It must be fast, and if it is slow, it will definitely be discovered by the North Carolina.

"Will you not be discovered after getting close?" Mu Haoyang asked Yang Yuanfan.

"Of course not."

"But..." Mu Haoyang hesitated for a moment and asked, "There are two working modes for attacking sonar. If we sail quickly, we will definitely make a lot of noise."

Yang Yuanfan was stunned for a moment, then smiled and said, "The attack sonar can indeed work in a passive way. Although its performance is not as good as the side sonar array, and it can only measure direction and cannot measure distance, it cannot work in a passive way when working in an active way. The infrasonic waves emitted by the attack sonar have high energy. When fully powered, the energy contained in a strike can heat a ton of seawater to 100 degrees Celsius. Although the infrasonic waves will attenuate in seawater and will lose half of the energy when reflected on the seabed or on the target, the sound listener on the passive sonar is a very sensitive electronic component and is easily burned by the reflected infrasonic waves."

"We have an angle with the North Carolina and will not be detected by the side sonar array?"

"Don't worry, don't worry at all." Yang Yuanfan was very patient. "The sound speakers of the side sonar array are also very fragile. In order not to be burned, when using attack sonar, the two sonar arrays located in the head of the boat will generally be closed. The Virginia class has a total of six large-aperture sonar arrays, three on both sides. After closing the two sonar arrays in front, it is equivalent to forming a sonar blind spot in front of the side."

"So, even if we launch torpedoes, the North Carolina won't notice it?"

Yang Yuanfan glanced at Li Xiaoming and said, "It is indeed the case in theory, but we don't need to take the initiative to attack the 'North Carolina'."

"Do you think the Americans started attacking sonar to shake the fish and shrimps in the Dead Sea?"

Yang Yuanfan smiled, looked at Zhou Yusheng, and said to Li Xiaoming: "It is useless to tell me. Whether to attack the 'North Carolina' is up to Lao Zhou to decide."

Li Xiaoming also looked at Zhou Yusheng, but said nothing.

The previous performance is enough to prove that Zhou Yusheng is a very independent and decisive submarine commander. On tactical issues, he will definitely not listen to the advice of a layman.

Zhou Yusheng is also considering this question: Should we attack the North Carolina in a favorable situation?

At this time, the North Carolina is like a firefly in the dark night. The Shark does not need to use attack sonar to obtain the necessary attack parameters, and even guide the torpedo to launch an attack using line guidance. Because the distance is too close, even if the torpedo uses self-guided method, the hit rate will not be too low. When faced with a head-on attack, the hope of "North Carolina" avoiding the torpedo is very slim.

It is not difficult to kill the North Carolina, but the difficulty is how to avoid the upcoming anti-submarine patrol aircraft.

The North Carolina has already sent out a communication buoy and sent a signal for help. After a maximum of twenty minutes, the three P-3cs can arrive. Although the North Carolina can sink within ten minutes, in the following time, the Shark will sail up to a few nautical miles. The P-3c only needs to drop a few sonar buoys that work actively to find the escaped Shark. Even if the torpedo launches a self-guided attack, the Shark will immediately turn to escape after launching the torpedo, and can only run about ten nautical miles before the P-3c arrives. This distance still does not exceed the detection range of the three P-3cs anti-submarine search.

Facing the anti-submarine patrol aircraft, the Shark has no way to fight back, and it is even more impossible to shoot down the anti-submarine patrol aircraft like sinking the North Carolina.

Attacking the North Carolina is equivalent to applying for a death notice in advance.

Can you get rid of danger without taking the initiative?

Zhou Yusheng was not absolutely sure, but he was not helpless.

As long as you can get close to the North Carolina in time and get close enough, then dive in an emergency and sneak under the belly of the North Carolina, the Shark will have the opportunity to enter the sonar blind spot of the North Carolina and avoid the upcoming anti-submarine patrol aircraft under the obstruction of the North Carolina.

This is not the best way, but the only way.

Seeing Zhou Yusheng's serious expression, Li Xiaoming was silent for a while, but still couldn't help but walk over.

Seeing Li Xiaoming coming, Zhou Yusheng sighed and said, "I will consider your suggestions, but you must abide by our agreement and I will fully command the tactical actions."

"Captain, I am not a submarine warfare expert, and I am not qualified to give you suggestions or suggestions." Li Xiaoming smiled and said, "I just want to tell you one thing."

"What's the matter?" Zhou Yusheng's face looked a little better, but he was still very serious.

"If I had to have a face-to-face game with the Americans, I would rather face one opponent than a few opponents."

Zhou Yusheng's brows jumped a few times, and he obviously heard the meaning of Li Xiaoming's words.

At the same time, dealing with the North Carolina and three P-3cs, the probability of the Shark's survival is definitely much lower than that of facing the anti-submarine patrol aircraft alone.

Only by promptly eliminating the "North Carolina" that is close to you can free up your hands to deal with the anti-submarine patrol aircraft.

Of course, Zhou Yusheng understood this principle.

It is only before making a decision, he must carefully measure the feasibility of the two tactics and the risks he bears.

This is his job alone, and no matter how advanced the computer is, he cannot help him complete such complex tactical evaluations and tactical analysis.

Zhou Yusheng must make a decision as soon as possible, because as the distance between the Shark and the North Carolina shortens, the opportunity to choose will soon be lost.

Ramons did not have so many concerns on the North Carolina.

After the attack sonar started working, Ramons issued only one order: to power the mk48-7 heavy anti-submarine torpedo in fish No. 1 and No. 4.

After discovering an "unidentified" submarine, you only need to input fire control data for the torpedo to launch an attack.

When the torpedo is powered on, the firing preparation time will not exceed twenty seconds.

For submarine warfare, which requires patience, twenty seconds are simply a blink of an eye.

However, it is not only Ramons who are considering tactics, but also Rodriguez, the first mate and navigator.

When the navigator came over, Ramons saw Campbell, who was sitting in front of the sonar console, looking back and looking very anxious.

"Campbell asked you to come?"

The short Hispanic captain, the navigator smiled and said, "I asked Campbell to reanalyze the noise signal and then draw a route map."

"Route map of enemy boats?"

Rodriguez nodded and said, "If the computer did not make any mistakes, the enemy boat was hiding on the hillside southwest of the Troy Sea Peak, and then entered from behind as we were going counterclockwise, then we must have followed us when we sailed west."

Ramons touched his chin and asked Rodriguez to continue.

The navigator was an officer or an officer with the second most powerful position on the submarine than the captain, so Ramons respected this subordinate more and did not dismiss him like he did to Campbell.

"The problem is that when we turned east, no abnormality was found." Rodriguez glanced at Ramons, "There is only one possibility: the enemy boat found us and stopped immediately after turning. Because we were hanging towing sonar at the time, the enemy boat would not be too close to us."

Ramons nodded thoughtfully, as if agreeing with Rodriguez's point of view.

Rodriguez drew a route on the chart and continued: "Because our steering radius is too large, the enemy boats have been in the detection area of ​​the side sonar array. We turned again and began to sail south, the enemy boats were on the west side of the Troy seabed peak. If we kept sailing south, the enemy boats would enter the sonar detection blind spot at some point and accelerate to catch up."

"You mean, the enemy boat is north of us?"

Rodriguez nodded and said, "It's not too far away from us. After we use the attack sonar, the ideal choice for enemy boats is to get close to us."

"Attack us?"

"If the enemy boats were going to attack us, they would have taken action long ago and would not have waited until now." Rodriguez hesitated for a moment and said, "If the enemy boats heard the sound of our projectiles, they would definitely know that the anti-submarine patrol plane was about to arrive. Their only chance was to get close to us and get under our belly."

"If so, we met a very powerful opponent."

Rodriguez smiled and said, "It's not too late to adjust the tactics now."
Chapter completed!