The sun is shining and the windows are shining. In the subtle morning breeze, the sound of the clanging of gold and iron from time to time faintly came from the slipway factory in the distance, bringing a little strange atmosphere to this originally quiet cabin.

"Submarines? Your Highness, what you are talking about, but the kind of gadgets that haunt underwater and are used for sneak attacks? Frick asked suspiciously. Qingying nodded and said, "That's right, I remember that this new class came out a long time ago. Frick twisted his beard with his fingers, his soybean-sized eyes narrowed slightly, and said, "But I remember, there doesn't seem to be a provision for the construction of this kind of gadget in the Navy Law, Your Highness, what are you going to do with this thing?" Qingying snorted and said, "Isn't this my personal hobby?" With this thing, you can carry out smuggling, smuggling drugs or something at sea, which is much more profitable than honestly building a ship. ”

Seeing Frick's face full of shock and a look like a ghost, Qingying couldn't help but roll her eyes. The Germans are just too rigid and rigorous, and have no other cells at all; What he said casually made this guy believe it and make this expression of dying! He shook his head a little helplessly and said, "What I said just now is just a joke, I need submarines for a more far-reaching purpose." This branch of the army has been in the Navy for decades, so there is not even a single designer who understands submarines in this shipyard, right? ”

Frick breathed a long sigh of relief and said, "Your Highness, you scared me to death just now. I'll just say, every year the royal family has nearly two million marks, and now that Your Highness has this shipyard again, how can you be short of money? As for the submarine designers......" he smiled slightly, and then said: "Your Highness, you can be regarded as asking the right person, the little Khedira in my team is a professional who is proficient in this field!" His original intention in researching submarines was to change his living conditions by using them to smuggle drugs. But later, as the empire began to develop maritime shipping, he found that the rewards of designing merchant ships honestly were also abundant, so he taught himself to design surface ships and became a member of our team. However, he didn't lose any of his skills in submarines, and always showed off his designs in front of us. ”

Qingying was pleasantly surprised, and said, "Then this Mr. Khedira, can he be here now?" Frick nodded, "He's in another office on the top floor, if His Highness wants to see him, I'll take you there." ”

Climbing stairs and ladders, panting. A few minutes later, Qingying and Frick walked into another room. The same flowers and bonsai, the same long cabinets, but the protagonist sitting on the seat has become a person in his thirties. Without waiting for the guy to ask suspiciously, Flick had already taken a step ahead of him and told his old partner what had happened.

After listening to Flick's story, the guy's eyes gradually narrowed; However, he did not show the expected surprise look, but a trace of confusion and incomprehension in his eyes. After a long while, he tilted his head slightly and said, "Your Highness, Frick should have told you, right?" I do have a lot of experience and attainments in the field of submarines, but if I don't know the purpose of the tunnel, I can't start designing it. I wonder why His Highness wants to get this thing? ”

After the introduction just now, Qingying already knew that the person in front of her was the little Khedira in Frick's mouth. In the face of his inquiry, Qing Ying said with a straight face: "Mr. Khedira, according to the assessment made by the Naval Staff, submarines will play a significant role in future wars. Therefore, I want Germany to be one step ahead of other naval powers in this area. Worried that the guy in front of him, who had never met before, would not buy his account, Qingying pulled up the banner of Tirpitz.

Hearing Qingying say this, the faces of the two people next to him put away their slightly relaxed expressions. In the past two years, Qingying has made a name for herself in the naval design industry, and the ideas she put forward have made those gold medal engineers who have been immersed in shipbuilding for decades suddenly open their minds, and no one dares to underestimate this 13-year-old boy who has just turned 13 years old. He himself has a keen insight in the navy that is unimaginable to ordinary people, and he has a close relationship with the chief of staff of the Navy, Tirpitz, and if he says that the Naval Staff has this new assessment, it is probably true!

At this thought, Khedira's face showed excitement, and he said, "It's amazing that the Admiralty would be interested in a smuggling ship like mine. But when I first researched it, I didn't add any elements of war to it; Now the Navy needs this kind of gadget, and it should have to put something else on it. Am I right? ”

Qingying nodded and said, "That's right." Since the submarine itself was too small in tonnage to engage in artillery battles with enemy warships, the Navy Staff decided not to install cannons on it, but to equip it with torpedo tubes that could fire torpedoes underwater. If this kind of torpedo-firing submarine can be built, we can let it dive underwater to attack enemy warships; As long as it is within our attack range, we can give it a hard shot! ”

Khedira shook his head a little disappointed, and said, "Your Highness, if the Navy's idea is like this, then I can say very responsibly that no one in the world can make this thing. Theoretically, this scenario is indeed feasible; However, there are two problems that are difficult to solve when it comes to concrete implementation. ”

"First, there is the issue of submarine power. Although submarines have evolved from primitive human-powered to steam-propulsion, they are still unbearably slow. At present, steam-powered submarines have a surface speed of only 3 to 4 knots, and a endurance of just over 150 nautical miles, and their speed and range are not even one-third of that of the oldest patrol gunboats! This low speed and range directly limited the range of activities of the submarine, making it impossible for this weapon to move near its own military port and not to go to sea to perform its tasks at all. In addition to this, since this steam power is coal-burning, it requires a lot of air; Once the submarine dives, it is covered with seawater on all sides, and the boiler can no longer continue to operate. And if the submarine is propelled by an electric motor, the consumption is too great, and the endurance is only one-third of that of steam power. ”

Khedira said: "Second, there is the problem of the torpedo itself. At present, the range of torpedoes is too short, and the effective range is only a few hundred meters, which greatly limits its scope of application. For example, the 350-mm torpedo that Germany commissioned five years ago had a range of only 400 meters; And even the latest 450-mm torpedoes have a range of only 1200 meters. This distance is simply not enough to see for the vast ocean, not to mention that the submarine still can't move underwater! Unless the opposing warship happens to pass in front of the torpedo tubes of our submarines, there is no chance of attack at all! Your Highness is proficient in the navy, and the probability of this kind of thing happening, I don't think I need to say it again. The idea of using submarines to attack the enemy's surface warships will not be possible without solving the two problems of submarine power and torpedo range together. ”

"Wait, Mr. Khedira, what did you just say? Submarines are powered by coal-fired steam? Qingying's mouth opened wide, as if she had heard some unbelievable news, and said with a look of surprise, "Did you make a mistake somewhere, how can this thing be used on a submarine?" Khedira was stunned and said, "If you don't use steam power, what is it for?" The compressed air engine is not as effective as the steam engine. Coal-fired boilers and steam engines are the most standard power for naval vessels. ”

Qing Ying increased his forehead with his hand and said in a tone full of helplessness: "Mr. Khedira, the reason why naval warships use steam power is that steam power appeared early, and second, the space in the ship is relatively large, which can meet the power combination of boiler and steam engine. However, on the submarine, it is necessary to analyze the specific problems in detail. The traditional steam power is a high-power device, and now it is completely a way to miniaturize and install it on submarines. Why can't we think differently and consider magnifying the gasoline engine on a car and installing it on a submarine? As far as I know, this kind of thing is much better than a pocket-sized coal-fired boiler in terms of calorific value and consumption, right? Qingying did not jump to the diesel engine in one step, because the real maturity of the diesel engine technique will have to wait until after the time point when the dreadnought appears.

Khedira's eyes lit up and he was surprised, "Yes, I really forgot that there is such a thing as a gasoline engine." This low-power internal combustion engine is not suitable for use on battleships, but it can be used on sampan-class submarines! If Benz and Daimler could provide a gasoline engine with enough power, I could have tried this new idea. However, the gasoline engine still consumes air, so what should be done after the submarine dives? A thin snorkel pipe alone is still not enough to meet the consumption of gasoline engines. ”

"Mr. Khedira, the British built a submarine powered by a battery 10 years ago, and the battery can work well under water. Therefore, it is possible to equip the submarine with two power units: when the submarine is on the water, it is powered by a gasoline engine, and after submersible, it is propelled by a battery. When the battery is exhausted, the submarine can also surface and start the gasoline engine to charge the battery. In this way, the problem of underwater maneuvering of submarines can be solved to a certain extent. Qingying reminded him.