The Pixiu lurked on Weizhou Island for three days, and Yang Weiwu made the first contribution and basically figured out the deployment of the devil. In particular, the situation of the Navy's ships in Nanwan Harbor.

One Kahisa-maru ad hoc seaplane carrier, two destroyers of about five or six hundred tons, and two gunboats of about three hundred tons.

After discovering that there was a seaplane aircraft carrier, Li Guang's eyes immediately lit up. Junk aircraft carriers are also aircraft carriers, and if you can sink an aircraft carrier, the impact is much greater than killing a destroyer.

There should be examples of submarines taking out aircraft carriers in World War II (Li Guang doesn't know), but there are no yet, and Li Guang is now looking forward to the first record of the Naval Resistance Army.

During the three-day waiting, the Pixiu also basically figured out the pattern of the activities of the warships. The activities of the army are very regular, and these little devils are really like working in the office, and they go out for exactly one minute every day.

At eight o'clock in the morning, four destroyers and gunboats were dispatched, and at eight o'clock in the afternoon they returned to the port. In the past three days, the garbage aircraft carrier has not left the port at all, but the planes have been dispatched twice a day, each time about five. On the other hand, the land-based Yuben fighter may have two fighters and four bombers, and it is difficult to fully grasp them because their actions are not regular.

According to this rule, the best time to attack an aircraft carrier should be during the day, because at this time, there is only one warship in the military port, and the strength is the weakest. But the problem is that Hainan's seawater is not polluted at all in this era, and the light transmittance is really good. The water is ten meters deep, almost crystal clear.

And in this Nanwan Port, the sea water is really not deep enough, the channel is only twenty or thirty meters deep, once the Pixiu appears, the little devil can see it clearly as long as he is not blind.

If you sneak attack at night, you are worried that the batteries of the little devils on both sides of the port, the entrance and exit of just over a kilometer are too easy to block. According to Yang Weiwu's intelligence, the little devil's defense is still quite tight. There were four 105mm guns on the batteries on both sides of the port. All of the Pixiu still remember the shell hit by the shell last time, and the 12mm shell could not withstand the 105mm shell at all.

Therefore, the best time for a sneak attack should be the devil's aircraft carrier taking the initiative to leave the port.

Kakumaru seaplane carrier, displacement: 6804 tons. The total length is 138.95 meters, and the draft is 8.77 meters. It is powered by a 7,740 hp diesel engine with a speed of 18.7 knots

Firepower: 2 single-mounted 10-year 120-mm L/45 anti-aircraft guns, 2 single-mounted three-year 76-mm L/40 anti-aircraft guns, 2 single-mounted Type 96 25-mm anti-aircraft guns, 2 13-mm machine guns

Carrier-based aircraft: six Type 95 water reconnaissance aircraft, four Type 94 water reconnaissance aircraft, with two catapults.

In fact, there is not much difference between the Awata Maru encountered by Kahisa Maru and Li Guang at Midway, and the firepower is actually weaker, and its biggest role is to carry fuel and supplies in addition to carrying reconnaissance planes.

Li Guang believed that there would certainly be no oil on the island, and there was no doubt that four small warships and more than a dozen planes would be indispensable for oil. In other words, sooner or later, Kakumaru will have to replenish supplies and fuel. It's just that this time interval is not easy to determine, and Li Guang has become more and more experienced in submarine warfare, and he can't eat hot tofu in a hurry, so patience can be greatly rewarded.

In the past few days, Ji Keliang's growth has been the greatest, and every night Ji Keliang commanded the Pixiu to dispatch, and if nothing else, he only used sonar to measure the terrain.

Active sonar has this function, but now active sonar is still very primitive, and this function is almost theoretical. Ji Keliang slowly figured out a set of methods, which can now be roughly used, and a few days later, a map of the seabed topography appeared in front of Li Guang.

With the advent of this map, Tikrian suggested an improvement to active sonar. He didn't understand mechanical and electrical, but Li Guang admired his suggestion.

Now the structure of active sonar is basically a transmitter that can turn the direction and a receiving network. The distance is confirmed by the time of the ultrasonic echo. However, due to the lack of accuracy of electrical components and the interference of factors such as seawater temperature, the measured distance is extremely inaccurate. But the direction is quite precise.

Now Ji Keliang suggested setting up three active sonars, so that the distance can be determined by different direction angles, and the error must be much less.

Li Guang knew that there was a sonar array in later generations, but he only knew this term, and he didn't know its principle, maybe this is the basic principle?

But then the calculation is very problematic, and in the era of computers, it is not a very simple matter to calculate such trigonometric functions. However, this problem was easily solved by the torpedo fighters of the mathematics major, as long as they got a few pieces of transparent plastic or glass, drew different functional curves on them, and stacked them together, it was easy to get the calculation results.

And the last question raised by Ji Keliang turned out to be to set up a small air conditioner for sonar. He found that as long as the German-made active sonar worked continuously for three minutes, the data drifted so badly that the static could have an error of more than 30 percent.

Don't look at Li Guang is not learning electronics, but he is also very aware of the impact of electrical heating after heating, which is common sense in later generations, and even children know that electrical heating affects the surname Neng. Li Guang had no way to improve the surname of ultrasound for the time being, but the method he adopted was much more scientific than that of Ji Keliang, making a new shell for the sonar, and at the same time installing air conditioners and fans to force ventilation. Li Guang's electronic knowledge is said to be more advanced than many people in this era, not to mention the principle of ultrasound, the principle of radar, and even the structure of the radar, but he does not understand electron tubes, only knows transistors and integrated circuits.

One of the reasons for the rapid development of technology during the war is that people are unleashing their wisdom when their lives are threatened.

The development of the Pixiu is such a process, using the backward submarine design of the United States during World War I, plus Li Guang's later insights, and then improving it from actual combat, and then thinking deeply to make further breakthroughs and development. In fact, the Pixiu has always been improved in battle, and the tactics and training subjects have also been explored and perfected step by step.

If Tikerian's idea can be implemented, then the combat mode of the submarine will change, and the submarine can launch torpedoes completely underwater, without even raising the periscope, which will undoubtedly increase the concealment of the attack, and the safety of the submarine will also be greatly improved.

Submarines of all countries in the world currently fire torpedoes on the surface of the sea. Or in shallow water. This idea of Tikrian made it possible to launch the torpedo in deep water, and for the torpedo, the design difficulty increased a lot, but in principle it was not too difficult. Just change the fuse settings of the torpedo, as well as the pressure-resistant casing of the torpedo.

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