Chapter 197 Super Submarine

During the extensive development of submarines in World War I, reaching its peak in World War II, submarines of that time couldn't be truly called submarines. They were more like boats that could submerge, making the term "submersible boat" more appropriate. At that time, submarine designs were essentially boat-shaped (conventional), resembling a regular boat. It is said that Leonardo da Vinci had conceptualized a ship capable of underwater navigation, but such vessels were considered evil, and he did not draw up a design.

The majority of submarine designs from World War I to the early stages of World War II were quite different from modern submarines. They closely resembled surface vessels and, to reduce wave resistance during navigation, the bow adopted a shape similar to surface ships. Most of these boat-shaped submarines spent more time sailing on the surface, much like surface vessels. Therefore, a significant technical characteristic of boat-shaped submarines was that their surface speed exceeded their submerged speed.

In the design of the new "Tiger Shark", Wilhelm drew significant inspiration from later conventional submarine designs.

Firstly, this "super submarine" completely abandoned the sharp bow design, adopting a unique double-hulled whale-shaped structure to reduce fluid resistance. It became the world's first vessel with a surface speed slower than its submerged speed.

The more rounded bow brought an additional benefit to submarine designers that was previously unattainable. A portion of sonar systems could be installed in the broadest location of this submarine's coverage angle. As a result, the submarine could detect its targets underwater from a greater distance and earlier, with only the stern being a blind spot.

The power of this sonar system lay in its ability to target torpedoes without the need for a periscope, enhancing its safety.

To reduce resistance during submersion, the entire submarine, except for the conning tower (control room), appeared exceptionally neat and clean on the surface, devoid of miscellaneous equipment. Even the radar antennas and forward hydroplanes were foldable. This not only maximized the submarine's speed but also minimized irregular parts generating more noise underwater.

The improvement of this "super submarine" went beyond its external appearance.

In terms of propulsion, the "Tiger Shark" was equipped with two "MAN" diesel engines (each with 1500 horsepower) and 380 maintenance-free lead-acid batteries, forming a massive super battery with a weight of 270 tons, the largest single-component functionality, occupying at least 10% of the submarine's displacement.

With this new power assembly, the "Tiger Shark" could achieve an astonishing maximum underwater speed of 19.5 knots. Its endurance at a silent speed of 5 knots (using the cruising electric motor) exceeded 100 hours. It only needed to surface periodically to charge at periscope depth. Fortunately, it had more space, featuring amenities such as a food refrigerator, shower facilities, and even fitness equipment that other German submarines lacked, significantly alleviating the crew's inconvenience of not being able to surface frequently.

Regarding silence, the first improvement was made to the propeller. The popular three-blade design was discarded in favor of a seven-blade large skew propeller for the first time.

In the battle between submarines and surface warships, submarines were always at a disadvantage. For submarines, constantly improving their silent performance was the basis for continued existence. When underwater sound noise could be comparable to the background noise of the ocean, it became extremely difficult for surface warships to detect submarines underwater.

Seven-blade propellers are asymmetrical, making them less prone to resonance and quieter. To achieve the same speed as a seven-blade propeller, the speed of a three-blade propeller must be at least ten times higher. High speeds can cause significant noise variations, and generally, faster speeds result in noise levels tens of decibels higher.

Although there are no modern multi-axis linked machine tools for precision machining, the absence of such equipment does not mean it is impossible to produce seven-blade skewed propellers. It just means that the resulting products won't achieve the same silent effect as those produced using multi-axis linked machine tools.

Moreover, the current underwater detection technology worldwide is not as advanced as in later years. Unless the periscope or ventilation pipe of a submarine is spotted, everyone must rely on sonar to roughly locate the submarine. Then, they compensate for the insufficient detection accuracy using the blast radius of depth charges.

Currently, submarines of various nations can travel underwater at a maximum speed of only four to five knots. Now, with a "super submarine" that has tripled or quadrupled the speed about to emerge, it means that traditional detection methods will be ineffective.

By the time the enemy detects its approximate location and drops depth charges, this "super submarine" has long escaped the destructive radius of the depth charges.

Of course, there is more than one method for achieving silence. In the later stages of World War II, under the powerful anti-submarine forces of the Allies, the German Navy's submarine force began to decline. Germany's U-boats were continuously sunk.

To reverse this situation and reduce the losses of U-boats, the German Navy's research institutions urgently developed a synthetic rubber sound-absorbing material called "Alberich". This rubber material, made into blocks about 3 cm thick, could be attached to the surface of U-boats to significantly improve their stealth performance. These rubber blocks, affixed to the submarine's surface, were considered the world's earliest sound-absorbing tiles for submarines.

In later years, the thickness of sound-absorbing tiles generally reached 150mm. Wilhelm was unsure how effective the Germans' 30mm thick sound-absorbing tiles would be, so he increased the thickness of the sound-absorbing tiles to 80mm.

Because the "Tiger Shark" has a double-hulled structure, sound-absorbing tiles are applied to both the outer and inner hulls. The outer layer of sound-absorbing tiles is mainly used to deal with active sonar, while the inner layer is mainly used to reduce self-noise. In addition, soundproofing and shock-absorbing mounts are installed internally for the engines and equipment with significant vibrations. After these efforts, this submarine can be considered the quietest submarine today.

Since the submarine is now larger, it means it can carry more supplies and more ammunition. Therefore, this "Tiger Shark" has an astonishing full load displacement of 2700 tons, truly a terrifying underwater giant.

In terms of weapons, this giant has powerful firepower with six torpedo launch tubes in the forward bow position. Moreover, the more specialized torpedo tubes are equipped with trendy hydraulic torpedo reloaders, allowing it to reload six torpedoes within eight minutes. With torpedoes ready in the launch tubes, it can launch 30 torpedoes within 30 minutes, exhausting all carried torpedoes.

Wilhelm couldn't help but exclaim, "I really look forward to it. I wonder which unlucky fellow will become its first prey."

Dönitz smiled and replied, "No matter who it is, they should feel honored. This is a revolutionary super weapon, and it's hard to imagine anything surpassing it."

Wilhelm chuckled inwardly; of course, there was something surpassing it. In later years, the underwater sovereigns were nuclear submarines. A strategic nuclear submarine in later years could easily destroy any medium-sized country and severely damage any major power.

Speaking of nuclear submarines, Wilhelm thought of the nuclear research department in Area 51. The small reactor built by Einstein before, which could only light up a building's light bulb, was a complete success. Ideally, the next step would be to build a real reactor. However, unfortunately, this war happened. If the nuclear power station were accidentally bombed by the enemy, turning into a German version of "Chernobyl", the loss would be too great.

Therefore, Wilhelm had to set aside the nuclear power station plan and let Dr. Einstein and his team continue researching nuclear power.

This was another challenge. After all, nuclear power was quite different from nuclear power plants in terms of fuel, structure, and coolant. However, following the timeline and with his support for German technology, it should take less than three years to develop.

And the high-speed centrifuge that he had been eagerly anticipating was finally constructed. Otto Hahn's nuclear weapons research group also accelerated its progress.