Chapter 383 Operation Starvation (7)

Japanese technicians continuously improved torpedoes, but the navy was still dissatisfied with their top speed and hoped for further enhancements.

At that time, Italy developed a torpedo capable of reaching speeds up to 50 knots. Japan immediately procured ten of these torpedoes for testing. During the experiments, they discovered the secret to the high-speed underwater operation: an air cavity at the front of the torpedo reduced water resistance (Italy wasn't only known for eccentric weapons; they had some serious innovations too).

Based on this insight, Japanese engineers modified the torpedoes' previously round heads by adding a sharp cap. As a result, the torpedoes achieved a speed of 50 knots, and theoretically, they could even reach 60 knots!

Additionally, Japan lacked the capability to produce pure oxygen. Consequently, they imported oxygen generators from Germany and replicated them at the Nagasaki Mitsubishi Arsenal for mass production. These generators were installed on cruisers and destroyers. Cruisers used oxygen extracted from gas, while destroyers used oxygen extracted from liquid. Although the latter's oxygen generator was smaller, it produced oxygen of decent purity. After a series of improvements and preparations, the Naval Torpedo School conducted test launches aboard the cruiser "Tone" in 1935. The results satisfied the military, and on November 28, 1935, the Type 93 Oxygen Torpedo officially entered service in the Japanese Navy.

Before World War II, the Type 93 Oxygen Torpedo stood as the pinnacle of torpedo technology worldwide. Its specifications far surpassed similar weapons in other countries.

Japanese technical experts at the time claimed that the Type 93 torpedo was 20 years ahead of the West.

The successful implementation of oxygen-assisted combustion significantly boosted the torpedo's power. Its range and speed saw substantial improvements. At the maximum speed of 50 knots, the range reached 22,000 meters, and at a low speed of 36 knots, it astonishingly extended to 40,000 meters!

This distance even exceeded the firing range of most battleships' main guns at the time. Moreover, the use of pure oxygen made the torpedo's wake extremely small, rendering it highly concealed and difficult to detect. Although there was a noticeable wake within the initial 300-400 meters due to the air-started main engine, this distance paled in comparison to the Type 93 torpedo's extraordinary range.

Beyond its long range, high speed, and minimal wake, the Type 93 torpedo's destructive power was unprecedented. Its explosive charge increased from 295 kg (Type 89 torpedo) and 400 kg (Type 90 torpedo) to 490 kg. This far exceeded the torpedo charge limits referenced in other nations' underwater protection designs. It's hard to imagine any ship withstanding the explosive force of nearly half a ton of TNT. These advantages made the Type 93 torpedo an immediate "secret weapon" in the Japanese Navy, classified as top-secret. Even personnel involved were forbidden from uttering the word "oxygen," using terms like "second air" or "unique air" instead, all in the pursuit of absolute secrecy.

The advantage of a time traveler lies in possessing knowledge from the future. What others painstakingly researched for decades can be summarized in just a few sentences for someone like me.

For example, the oxygen ratio in the oxygen torpedoes posed a challenge for Japanese researchers. They faced numerous accidents, failures, and setbacks while attempting to determine the correct ratio. Countless technicians were lost in the process. Yet, with a single sentence, Wilhelm pointed out the solution. Additionally, they improved the torpedoes by installing their own "acoustic homing system."

Logically, adding so many components to the torpedo would create tight internal space. However, the German technical department replaced the original high-explosive warheads with air-fuel explosives.

As a result, when the torpedo struck its target, the residual high-pressure oxygen from the propeller would spray out, forming an air-fuel explosive powder-oxygen cloud. Igniting this mixture would result in an explosion equivalent to 500 kg of TNT, even though the actual air-fuel explosive weighed only 60 kg. This power was sufficient to easily destroy large ships. If detonated close to the water's surface, the explosion would create an air-fuel explosive powder-oxygen "bubble" underwater. The explosive force of air-fuel explosives in oxygen-rich water far exceeded that in air. Upon detonation, the high-pressure shockwave could rupture the side armor of the target, causing it to rapidly take on water and capsize.

As Submarine Captain Schepke issued the launch command, a torpedo plunged into the sea, hurtling toward a transport fleet 15 kilometers away at a speed of 50 knots (approximately 93 kilometers per hour).

Five minutes later, the torpedo's acoustic guidance system activated, having already covered more than 7,000 meters. It detected a slight deviation in its course and adjusted its direction using the pendulum control system, aligning itself with the transport fleet.

In the original timeline, the introduction of acoustic torpedoes by the German Navy caused considerable panic among the Allied forces. These torpedoes seemed to have a keen eye, specifically targeting large-tonnage vessels. When a small boat sailed near a larger target, the torpedo would ignore the small boat and home in on the noisier ship.

However, once the Allies understood the characteristics of these acoustic torpedoes, their weapons experts quickly devised countermeasures. Their overall strategy was to "create more significant noise where our own warships are not present to disrupt visual and auditory tracking." They deployed noise generators, enticing the acoustic torpedoes to move away from the target area, ultimately changing the situation from passive defense to active offense for the Allies. Simultaneously, the Allied nations intensified their use of radar and sonar to search for and engage German submarines lurking beneath the sea.

This is also why Wilhelm strictly prohibited large-scale use of acoustic torpedoes in submarine fleets. After all, once these torpedoes are widely deployed, their characteristics become easily detectable, rendering them no longer a secret weapon.

At the thirteenth minute, the torpedo had already penetrated the transport ship convoy, yet its excellent stealth capabilities easily evaded the destroyer ships patrolling the perimeter.

Despite the various engine noises surrounding it, the torpedo's acoustic guidance system had locked onto a large transport ship ahead.

This particular vessel weighed at least 20,000 tons and was laden with much-needed special steel for Britain, along with several rare metals. The ship's draft was already quite deep, and despite running its engines at full power, its speed barely reached a pitiful seven knots.

The torpedo collided head-on with this transport ship.

Boom! A deafening explosion erupted, sending a towering column of water skyward.

Due to its metal cargo, the ship's remaining buoyancy was minimal. Struck suddenly by this massive blow, the cargo ship split into two pieces, sinking rapidly.

To make matters worse, another transport ship followed closely behind, almost tailgating the first one. With no room to maneuver, the bow of the trailing ship rammed into the stern of the already sinking vessel.

Thud! The dull impact sound echoed as the front ship's bow forcefully pierced the rear ship's stern, creating a long gash.

Although it seemed perilous, this wasn't a crippling blow. Perhaps with some repairs, the ship could continue its journey. However, before the crew could react, accompanied by a deafening blast from the ship's whistle, the second transport ship rammed into the scene. The result: a three-way collision. Unfortunately, the middle ship was now beyond salvage.