Chapter Five Unique and Unparalleled

  The East China Sea southeast of the Ryukyu Islands.

  At a depth of 250 meters below the sea surface, the "Swordfish" submarine, about 80 meters long and 11 meters wide, with a dark body like a stretched cigar, has a streamlined command tower, retractable horizontal rudder, X-shaped tail rudder, driven by pump-jet propellers, is moving slowly forward at a speed of six knots along the ocean current.

  Inside the command center, Hua Jianfeng stared intently at the two bright spots on the fire control computer screen.

  If the "Swordfish" commanded by Huajianfeng is a sharp sword, then the two nearby "Chaoxiao"-class AIP conventional submarines equipped with Stirling engines produced by Swedish Kockums are ancient bronze swords dug up from underground that should have been put in a museum long ago.

  "Captain, target number one is surfacing, shall we follow?"

  "Follow the first target boat closely, keep a close eye on the second target boat." Huajianfeng walked to the back of the helmsman, "Control the heading and speed well, when the depth reaches 50 meters, start the underwater camera, let's take a look at this new friend's appearance."

  The "Swordfish" quietly followed behind that Japanese submarine and headed towards the surface of the sea.

  Two years ago, when he was transferred from the "Gun Octopus" nuclear submarine to take command of the "Swordfish", Hua Jianfeng felt that he had been "exiled" and was depressed for two months. Because the "Gun Octopus" was the most advanced attack nuclear submarine in the Republic, while the "Swordfish" was just a conventional submarine.

  But "Swordfish" was no ordinary conventional submarine.

  "Longxing New Energy Company" first developed and produced not civilian composite batteries, but military composite batteries with an energy density of 8 kilowatt-hours per kilogram. Later, the composite battery used in Jiqing Company's electric vehicle had an energy density of only 2 kilowatt-hours per kilogram, which was only 25% of the performance of the military version.

  In the military, this high-performance composite battery has another name: "Dragon Soaring Battery".

  What is the significance of a mass-energy equivalence ratio of 8 kilowatt-hours per kilogram?

  The calorific value of diesel combustion is 40,000 kcal/kg, the calorific value of gasoline combustion is 44,000 kcal/kg, and "Longxiang Battery" can store 28,800 kcal/kg of electricity, which is 72% of diesel and 65.5% of gasoline.

  The thermal efficiency of direct-injection internal combustion engines is around 50%, and the energy conversion efficiency of superconducting motors is over 70%. The power propulsion system composed of "Long Xiang Battery" and superconducting motor can completely replace the power propulsion system composed of diesel, internal combustion engine and ordinary battery, making conventional submarines truly have "AIP", that is, "non-air-dependent propulsion device".

  Equipped with a 400-ton "Long Xiang Battery" and a 7,500-kilowatt superconducting electric motor, the "Jian Yu" can dive at a maximum speed of 27 knots for 296 hours after being fully charged, traveling 8,000 nautical miles in 12 days. If the diving speed is reduced to 6 knots, it can dive for 72 days and travel 10,000 nautical miles without surfacing for air during the entire patrol mission. In comparison, even if equipped with fuel cells, the conventional submarine of the 212 class can only dive for up to 21 days, and if traveling at maximum underwater speed, it can only last a few hours.

  The "Swordfish" can be charged at any port equipped with a special charging device. If electricity is obtained from the civilian grid, the charging time is twelve hours; if there are specialized high-power generators, it only takes two hours. Conventional submarines equipped with AIP systems must replenish liquid oxygen or special fuels in military ports with matching logistics support capabilities, which is difficult to obtain logistics support in commercial ports.

  The power system consisting of "Longxiang Battery" and superconducting electric motor has another advantage.

  Apart from a diesel engine for emergencies, the "Swordfish" submarine had no other conventional power equipment and therefore no major noise sources. Combined with its pump-jet propulsion system, the "Swordfish"'s noise level was reduced to an unprecedented degree. At six knots, its own noise was less than 70 decibels; even at 27 knots, it was only 98 decibels, far lower than any conventional submarine and several decibels lower than the US Navy's Virginia-class nuclear submarines.

  The hull of the "Swordfish" was covered with a 35 cm thick sound-absorbing coating, which reduced the detection distance of enemy boats' active sonar by two-thirds. With extremely low self-noise, the "Swordfish" became the quietest submarine in the world.

  The "Swordfish" is still far from perfect.

  "Long Xiang" batteries are extremely expensive, the price of 400 tons of batteries exceeds that of an attack nuclear submarine, so its endurance is far inferior to that of a nuclear submarine. If a small fusion reactor is added to the "Swordfish", it can give it the ability of "infinite endurance".

  Restricted by the diameter of the hull, especially the tail diameter, the power of the superconducting electric motor cannot be further increased, limiting the maximum navigation speed of "Swordfish", and the maximum submerged speed of only 27 knots is still not comparable to that of the most advanced attack nuclear submarines.

  The length of the "Xiaolong" is only 80 meters, and the middle cylindrical cabin section is less than 55 meters long. The passive sonar array on the side is only 50 meters long, which is nearly 30 meters shorter than the passive sonar array on an attack nuclear submarine. As a result, the performance of the passive sonar, especially its ability to detect the direction of sound sources, has been greatly reduced.

  Due to the limited space in the bow, even if the torpedo room is moved aft and four torpedo tubes are installed on the sides of the submarine, only a six-meter-diameter spherical main/passive sonar can be equipped at the bow, so the active sonar performance of "Swordfish" is not as good as that of "Gun Octopus".

  Finally, due to the limited internal space of the hull, "Swordfish" can only carry 22 torpedoes and missiles, which is far less than the 38 torpedoes and missiles carried by "Gun Octopus".

  For a conventional submarine with an underwater displacement of only 3,350 tons, the performance of "Swordfish" is already quite outstanding. Not only can no conventional submarine match it, but even the French Navy's "Barracuda"-class attack nuclear submarines are not necessarily much stronger than "Swordfish".

  After seeing "Swordfish", Hu Jianfeng immediately changed his previous view.

  What surprised him even more was that the Republic Navy only built one "Swordfish". Mainly because of its price tag of 18.4 billion, which made the navy hesitant to take it on. If not for taking on the role of a "testbed", the navy would have rather spent the same amount of money to procure two "Gun Octopuses". The captain assigned to the "Swordfish" was not a demotion, but a promotion.

  For the next two years, Hua Jianfeng called "Jianyu" home.

  As "Assembly Dragon", Hua Jianfeng participated in the construction of "Swordfish" and put forward several very valuable opinions to engineers during this period.

  Through relevant work, Hua Jianfeng gained a deeper understanding of this submarine.

  In addition to having a strong "heart" and a large enough "lung", the "Swordfish" also has a well-developed "brain".

  The highly automated operating system, and the posts saved after the removal of conventional power equipment, reduced the crew of "Swordfish" to thirty-four people, normally only eight people were needed to control the entire submarine. The highly integrated detection, search and fire control systems, combined with a central computer running 250 million times per second, gave "Swordfish" the most sensitive reaction speed. In combat, "Swordfish" could track eight targets at the same time, controlling four torpedoes to attack two of the most threatening targets.

  A good horse deserves a good saddle; a brave warrior deserves a precious sword.

  The "Swordfish" was equipped with the most advanced weapons, especially heavy torpedoes.

  The new electric torpedo uses a composite battery as the power source. In high-speed mode, it has a range of 35 kilometers at 70 knots; in low-speed mode, it can reach a range of 65 kilometers. The warhead is equipped with 250 kilograms of high-energy explosives, which is enough to cause significant damage to a destroyer with one torpedo, or a cruiser with two torpedoes, and three torpedoes can render an aircraft carrier unable to fight.

  Everything made Hua Jianfeng overjoyed, he thought "Swordfish" was more like a super submarine in science fiction.

  Half a year ago, after the "Swordfish" was officially put into service, Hua Jianfeng and 33 other officers and men had new tasks. Within five months, the "Swordfish" participated in three joint military exercises, and its performance was fully affirmed.

  A month ago, Hua Jianfeng set sail again.

  Their mission was to track down the second Japanese Navy submarine that had been upgraded with an AIP system and was training in the waters around Okinawa.

  Up until now, "Swordfish" had been tracking those two Japanese submarines for eleven days.

  Three days ago, after completing the last task, "Swordfish" used active attack sonar to "greet" that Japanese submarine. As a result, more than 20 "Sea Hawks", eight P-3C "Orion" anti-submarine patrol aircraft and hundreds of sonobuoys were called in by the Japan Maritime Self-Defense Force. The "Swordfish" did not leave and remained behind the Japanese submarine, taking the opportunity to understand the Japanese submarine's anti-submarine tactics.

  Two days ago, another "Shang" class submarine arrived.

  If it comes to a fight, Hua Jianfeng is confident he can take down two "Jianchao" at the same time.

  "Captain, we're at fifty meters now."

  Hua Jianfeng came back to his senses. "Turn on the external illumination lamps, enter from the rear of the enemy submarine, and let's take a closer look at the appearance of the little devil's new submarine."

  A blurry figure appeared on the screen of the fire control computer.

  The eighty-meter-long, ten-meter-wide Japanese submarine was like a huge whale, quietly floating twenty-five meters below the surface of the sea. The Japanese submarine was testing its new non-penetrating photonic mast and satellite communication equipment, completely unaware of the "Swordfish" that had appeared behind it.

  "It's just like a big sea cow. With a conductor's podium from the bottom, dozens of little devils will be done for."

  "I'm reluctant to give it up." Hua Jianfeng smiled faintly, "Go around from the left side, slow down to second gear, and see if the little devils can hear our voices."

  The "Swordfish" slowly turned and came up on the left side of the Japanese submarine.

  "Captain!" The sonar chief suddenly shouted, "Contact!"

  Hua Jianfeng's eyebrows furrowed slightly. "Been discovered?"

  "No. Ten o'clock direction, very far away, very faint."

  "An American nuclear submarine," said Le Jia Cheng as he walked over. "Perhaps it's the Los Angeles of the Seventh Fleet."

  "It should be 'Seawolf' or 'Virginia'," Sonar corrected the executive officer's statement, "There is no matching characteristic noise data, definitely not 'Los Angeles'."

  At this time, a freshly printed order came out of the laser printer.

  "Emergency dive." Hua Jianfeng quickly finished reading the just-received order and handed it to Le Jiacheng. "We've already completed our mission, we should have returned long ago."

  After reading the order, Le Jia let out a faint sigh and nodded slightly towards the helmsman who turned back to look at him.

  The General Staff Headquarters has issued a recall order, "Swordfish" should go home.