"Captain, you can float in half an hour, do you want to raise the periscope?"

"No, is there any contact?"

Liao Hongpeng put on his coat and walked into the command center of the submarine.

"No, there was a lot of wind and waves on the sea, and I didn't hear any unusual noises except for the courtship of a few whales."

The listener immediately replied. Unlike the destroyer, there is no sonar installed on the submarine, only a listener (in fact, it is the most primitive passive sonar, but the performance is very backward) Liao Hongpeng nodded. "All departments are ready, and as soon as they get up to the top, they start charging. This neighborhood is a frequent haunt of US Navy patrol aircraft, and we can't stay on the surface for long! ”

The order was immediately given, and the submarine immediately became lively.

Liao Hongpeng took over the "C" submarine, numbered "1O9," three months ago. This was the first type of submarine that the Imperial Navy was equipped with during the war and was intended to replace the "B" type submarines.

In terms of overall combat capability, the biggest characteristic of the "C" type submarine is that its endurance is much higher than that of the "B" type submarine, and the number of mines carried by it has also increased a lot, so the displacement of the submarine has also increased a lot, and in other respects, the difference between the submarine and the "B" type submarine is not very large.

As the first type of capital submarine of the Reich (it was the "main submarine" and not the "main fleet submarine", the Imperial Navy has always not treated submarines as capital warships, so submarines will never easily participate in the decisive battle of the fleet), the "B" type submarines did not perform badly during the Great War. In the first two years of fighting, a total of more than 150 Type "B" submarines were active on the battlefield, most of which were concentrated on the routes of the North Pacific. Within two years, the average tonnage of merchant ships sunk by an "B" submarine was close to 100,000 tons! In other words, these Type B submarines alone would be enough to paralyze Japan's external shipping. But the problem is that the problem of short legs of Type "B" submarines cannot be solved.

Before the "C" submarines were put into service, the Imperial Navy also specially modified more than a dozen "B" submarines to carry more fuel, keeping only the torpedoes in the torpedo tubes. Serves as a supply submarine. Others carried a large number of torpedoes, replenishing other submarines with torpedoes. This is only a drop in the bucket, and at most it can only help some of the "B" submarines to be active at sea for a longer period of time, but cannot fundamentally change the problem of short legs of submarines.

In response to this situation, the Imperial Navy put forward a request for submarines with a longer range. The "C" type submarine also came into being. In fact, the submarine of the "C" type was the Don Imperial version of the submarine of the German Navy Type IX. At that time, it was almost impossible for the Don Empire to redesign a submarine, it was mainly a matter of time. It will take two or three years from the establishment of the project to the launch, and the United States is in the middle of the war, and the Imperial Navy urgently needs a submarine that can sail to the Central Pacific Ocean to carry out diplomatic breakage and reconnaissance missions. As a result, the Don Empire directly selected the German Type IX submarines and made some simple design modifications. For example, the front pressurized water tank in the submarine was changed to an oil tank, and the bow torpedo tube was increased to six (a major feature of the Tang Empire's submarines, which strengthened the attack force), so the displacement of the "C" type submarine was larger than that of the Type IX submarine, and the range was slightly longer. It fully met the needs of the navy of the Tang Empire.

Liao Hongpeng was the first captain to accept the new submarine. Before this mission. He had already conducted a month-long combat patrol in the North Pacific, sinking several small American cargo ships (mainly American ships carrying cargo to the Aleutian Islands, not ships bound for Japan). The combined displacement of several small cargo ships is less than 5,000 tons. The last combat operation was mainly to test the performance of the submarine and to familiarize the dozens of officers and men on the ground with the new submarine as soon as possible.

More than 20 days ago, Liao Hongpeng returned to Naha Port after completing his combat mission, and according to the regulations, they should have at least ten days of vacation in order to allow the officers and men to regain their energy. But on the third day, Liao Hongpeng received a new order to go to the Hawaiian Islands to carry out combat patrol missions. Halfway through, he received another order. Conduct a vigilance mission in the waters near Midway, the westernmost part of the Hawaiian Islands. And this time is March 29th.

Any submarine captain knows the meaning of this order. The task of combat alert is to patrol the predetermined sea area, monitor the situation in the sea area, and if the enemy fleet is present, it must immediately send a telegram. Obviously, this is a very dangerous task. There are two ways for submarines to present the enemy fleet, one is to listen, but to watch. Listening is to use the sound of the sound to distinguish the sound of those ships, to judge whether it is a warship or an ordinary ship, and a good listener can judge the warship and the ship through the sound, but it is difficult to make a clear judgment. For example, the type of battleship, the number of warships, and so on. To see is to observe with a periscope, so that you can accurately judge the size of the enemy fleet, as well as the type of battleship. This is also very dangerous, at night, the periscope can only be seen at a maximum of several nautical miles, and if you want to see the enemy's main battleship clearly, you must enter the anti-submarine patrol range of the enemy fleet, and the periscope of the submarine can easily be seen by the destroyer.

Liao Hongpeng looked at his watch, it was already 6:45 in the evening (the submarine captain's watch will be adjusted in time according to the different time zones of the submarine's activities) He nodded to the first mate standing next to the periscope, and then walked over. Before the submarine surfaces, it is necessary to determine the situation on the surface of the sea with a periscope, and it is not until it is confirmed that there are no enemy warships nearby.

"At a depth of 15 meters, you can raise the periscope."

The first mate glanced at the depth gauge.

Liao Hongpeng looked at the listener.

"No sound contact!"

"Okay, let me take a look at the situation first."

Liao Hongpeng walked to the periscope and put down the handles on both sides of the periscope.

"Stop ascending and prepare to raise the periscope."

The first mate immediately shouted.

When the bow rudder of the submarine was leveled and stopped rising, it shook slightly, and then it was suspended at a depth of about 15 meters above the sea surface. Liao Hongpeng took a deep breath, then pushed the periscope up, and the servo mechanism attached to the periscope was immediately activated, lifting the periscope out of the water. Every time the periscope is raised, it's an adventure, and who can guarantee that right on it there will be a destroyer that doesn't move?

The periscope was raised smoothly, and Liao Hongpeng put his eyes on the eye protection cover of the eyepiece, and then quickly turned it. He first used a short focal length lens to quickly observe the sea situation within 360 degrees of the surrounding area, and there was no shadow of the existing warship. Then, he slowly rotated the periscope with a telefocal length lens, and looked at it again, confirming that there were no warships on the sea.

"It's fine. No one is eyeing us! ”

Liao Hongpeng put away the periscope, and then took out a cigarette. You can't smoke on a submarine, and although the captain has the privilege, most of the time, Liao Hongpeng doesn't smoke, because no sailor likes to see someone else smoking on a submarine.

"Floating?"

Liao Hongpeng nodded, took out a match, and he was going to wait for the submarine to float before lighting the cigarette.

"Captain. There is an anomaly! ”

Before the first mate could give the order, the listener immediately called out. Liao Hongpeng was startled, the cigarette in his mouth fell on the deck, he rushed over with an arrow, installed a spare earphone, and stuck it to his ear. Everyone else in the command module held their breath, it was a time of life and death.

Voices come from far and near, and Liao Hongpeng himself is also an expert in acoustics (many submarine captains have been trained in this area, and in the sea, submarines rely on their ears. and not eyes) The first mate walked over with a light step. As if he was afraid of making a noise to the captain.

"It's the sound of propellers, there are a lot of them, not a battleship. It's a fleet, yes, it's definitely a fleet. ”

The ears of the listener are the most sensitive on the entire submarine, "Captain, do you hear it, there is also a dull sound, it is the noise of the plane flying at low altitude, it is coming towards us." ”

Liao Hongpeng nodded slightly and handed over the spare headphones to the first mate. "It should be a fleet, and quite a few planes. Looks like we've caught a big fish this time. ”

"Are you going to prepare for an attack?"

When the first mate heard this, he was also excited.

"No, dive to 25 meters and don't prepare for an attack."

Liao Hongpeng took out another cigarette, and this time he lit it without hesitation, "Go and call the messenger, and mark our location on the chart." Xiao Gong. Is it possible to judge the number and size of enemy battleships? ”

"It should be possible, but it's hard to judge the type of battleship!"

The listener replied immediately. If the distance is close enough, he can judge how many propellers those warships have by the strength of the propeller noise, as well as the sound of mutual disturbance, and this is an effective way to judge the size of the battleship, for example, destroyers generally only have two propellers, while large warships have three, or even four propellers (three are rare, four are the majority) In addition, the larger the displacement of the warship, the larger its propellers, and the more dull the noise, A good listener can roughly judge the displacement of a battleship by the noise of the propellers, but it is impossible to distinguish an aircraft carrier from a battleship with a similar displacement.

Liao Hongpeng nodded slightly, and said to the first mate: "Enter the combat state, and all noise is strictly prohibited." ”

"Enter the ...... of Battle"

Dozens of officers and men on the submarine went to their posts, and all of them tried not to make noise as much as possible. The active sonar on the destroyer can scan the nautical mile, but in general, if the destroyer does not confirm the presence of submarines in advance, it will not use active sonar, but will use the method of listening (that is, passively receiving the sound in the sea) to determine whether there is submarine activity around. At this time, if the submarine makes noise, it will be revealed, and the result will be sunk!

The submarine's propeller quickly stopped rotating, and like a huge iron box, it was suspended in the sea about 25 meters above the surface. The fleet on the surface of the sea was approaching rapidly, and it was obvious that it was only a little more than ten knots, and there were anti-submarine destroyers coming forward.

Liao Hongpeng glanced at the first mate, and both of them were quite nervous. On the sea, submarines are most afraid of two opponents, one is a destroyer, and the other is an anti-submarine patrol aircraft. Those large warships that show off their might on weekdays basically do not have anti-submarine capabilities, and if the aircraft carrier is not covered by anti-submarine destroyers, any submarine can easily kill the aircraft carrier, and the aircraft carrier has not yet fought back. But the problem is that any aircraft carrier is covered by several, if not a dozen destroyers. At the time of the destroyer attack, the survival rate of the submarine was less than 20%. In other words, as long as the destroyer appears, the vast majority of submarines will have only one destination!

Liao Hongpeng had tasted depth charges, and he didn't want to do it again.

"Captain, the fleet is above us!"

There is no need to listen to the voice report, Liao Hongpeng and they all know that the fleet is on top of the submarine, because those huge noises directly pass through the hull and enter the inside of the submarine, and everyone can hear the noise from the propellers, as well as the dull sound of the boilers on the battleship.

"I really want to go up and do a shot!"

Liao Hongpeng laughed at the grumbling first mate, he didn't laugh out loud, now only a fool would provoke a fleet of more than a dozen destroyers.

"Captain, the enemy fleet is moving away, there are about seven large warships, three of which have a displacement of more than 10,000 tons!"

"Okay, get ready to ascend to periscope depth!"

Liao Hongpeng walked to the periscope, and then glanced at the messenger who had just come over, "Find out the location of the submarine, and then prepare to report." ”

"Lao Liao, is it a little too early?"

The first mate immediately came over, and there were definitely destroyers behind the enemy fleet.

Liao Hongpeng hesitated for a moment, and then said, "Then we'll wait for another fifteen minutes!" ”

Time passed quickly, fifteen minutes later, the periscope was raised, Liao Hongpeng had not adjusted the focus of the periscope, and immediately saw the aircraft carriers that were turning in front of him, not a few, but three, three large fleet aircraft carriers with flat decks, and then, he saw several destroyers that were heading towards him. Liao Hongpeng was so frightened that he almost didn't jump, and he immediately put away the periscope.

"Maximum dive depth, emergency dive, damn it, we've been revealed!"

"Captain, destroyer, sonar contact!"

The alarm sounded immediately, and the submarine, like a whale, immediately plunged into the depths of the sea. The sea area near this is close to Midway, and the water depth is only about 2oo meters, but the maximum diving depth of the "C" type submarine is 15o meters, and the ultimate diving depth (refers to the extreme depth that the pressure hull can bear, submarines generally do not dive so deep) is 18o meters. It was not easy to dodge the two destroyers overhead.