In the early morning of January 11, 1942, under the gray-brown Mediterranean skylight, a Viic-type U-69 submarine was swimming on the sea.

The design of the Vii-class U-class submarine was started with the Ubiii-class submarine. After World War I, due to the restrictions on the Treaty of Versailles, Germany was not allowed to own submarines. The military instead funded the shell company established by its own shipbuilding company in the Netherlands - the Ship Construction Engineering Bureau, to secretly study new submarines.

The vii-class U-type submarine is the most produced submarine in history. A total of 709 have been built and many types are also available.

The most famous of them is the Viic type. The Viic type submarine has been the main force of the German submarine force in World War II since 1941, and its construction work has not been terminated throughout the war.

The viic submarine is a powerful combat machine and is the most attacking submarine of the German Navy. It can be seen in almost all waters where German submarines are active.

The diving depth of the last viic/41 submarine of the viic submarine was not reached for a long time after the war.

The boat has 52 crew members, a length of 67.1 meters, a width of 5.85 meters, a water displacement of 769 tons, an underwater displacement of 871 tons, a maximum surface speed of 17 knots, a maximum underwater speed of 8 knots, a water range of 15,742 kilometers/10 knots, an underwater range of 148 kilometers/4 knots, and a designed dive depth of 220 meters.

There are 5 torpedo tubes, 14 torpedoes in total, and the equipment is equipped with 105mm deck cannon and 1 20mm machine gun.

As the first Viic submarine to be in service, the U-69 has been in service for almost two years, and the captain is Captain Hessman, 30 years old.

This is his third combat patrol with U-69. Their super long endurance has allowed them to stay in the Mediterranean for 4 months, with a cumulative record of 3 merchant ships totaling 12,780 tons.

At this moment, u-69 took on an important task: searching for the Allied fleet that launched an attack on the port of Tobrook and waiting for an opportunity to intercept the Allied fleet.

After receiving the relevant instructions last night, Captain Hessman ordered the U-69 submarine to search the waters where the Allied fleet is located as fast as possible.

Hard work pays off. Finally, before dawn, the U-69 submarine discovered the Allied fleet returning at full speed.

Immediately afterwards, Captain Hessman immediately reported the information to the U-boat General Command.

After learning about the relevant information, Chang Yuan's U-boat General Command, who was located in Germany, immediately convened a group of U-boats patrolling at sea to form a wolf pack, and designated the U-69 submarine at a better location to serve as the contact tracking boat for the entire wolf pack, providing intelligence to the wolves and headquarters.

The U-boat Command Center for this combat was extremely high. A total of 10 U-boats were mobilized to cruise in the Mediterranean and issued a supervising telegram very rarely: "Don't shrink, move forward as quickly as possible."

The u-69 is pressing far ahead of the fleet, constantly reporting the fleet's location to the headquarters and other members of the wolf pack. Currently, 4 U-boats have gathered on the Allied routes, and 6 are gathering at the fastest speed.

"Oh, Shet, what's going on? Did they find us? How is this possible!"

However, at this moment, u-69 suddenly discovered that an escort destroyer was heading towards him near the horizontal line more than 10 kilometers away!

Not only that, there is also an anti-submarine aircraft flying in at an extremely fast speed!

"Fake! Hurry, dive now!"

Seeing this, Captain Hessman immediately ordered an emergency dive. Its 105mm deck gun and a 20mm machine gun were far from the opponent of destroyers and anti-submarine aircraft.

Hessman didn't even have time to report to the command center. He must be very surprised: At such a long distance, did the escort warship really discover me? Is there a new type of long-range radar?

But the Metox receiver on his boat didn't respond at all.

Soon, the German local U-boat command also discovered similar problems. Allied escort warships and anti-submarine aircraft were becoming more and more active, and often the wolves took the initiative to welcome them when they were still in formation.

This makes the U-boats forced to dive, and once they submersed, the U-boats had a speed of only a little over 7 knots, which would be easily thrown away by the fleet.

U-boat commander Denitz and his staff speculated that the Allies may have already had a new radar with a working frequency outside the alarm receiver band of U-boat.

Their guess is correct. The Allied new carrier-based centimeter-wave radar was put into use at this time, with a wavelength of 9.7 cm, much smaller than the 1.5-meter wavelength of the previous 286 radar.

The Metox alarm receiver on the U-boat used to listen to the meter-pole radar is completely unaware of the existence of the new radar.

Moreover, after the wavelength is reduced, the volume and weight of the radar is greatly reduced, and warships and aircraft can be easily carried; the resolution of the radar is greatly improved, and even periscopes on the water can be found within a certain range.

"I'm, Shet! Hell!"

"Quick, dive now!"

The other three U-boats were all panicked at this moment, panicked and dived at the fastest speed. Faced with the joint attack of destroyers and anti-submarine aircraft, they could not stand it at all!

Currently, submarines must use electric power when underwater attacks to maintain good silence. If you dare to use the diesel engine during cruise, it will automatically send a head.

However, since today's motor batteries are old-fashioned lead-acid battery batteries, the battery can maintain a sailing of up to half an hour to about one hour underwater.

Therefore, before the U-boat launches an attack, the submarine must be charged with a diesel engine so that the battery can be full. Otherwise, the loud voice of the diesel engine during underwater charging will not be mentioned. The harmful gases generated by the battery during charging can poison a ship of people.

There are several other tasks to ventilate and summon the wolf pack. After the wolf pack arrives at the meeting place, the wolf pack will discuss the action plan and coordinate the action plan.

Because the current underwater state cannot communicate effectively and quickly, it must be in the floating state.

This is why so many U-boats have to float together when implementing the wolves tactic.

The high speed of carrier-based aircraft can ignore the distance. Even if there is only one direction, high-speed aircraft can quickly search along this direction.

Often, U-boats are caught before they can dive, because it takes one minute for these big men to dive from the water. Even if these four submarines are not completely exposed, they just leak the periscope for observation.

But at this moment, they are facing an extremely fast anti-submarine aircraft. It is not so easy for them to quickly submerge and get rid of the lockdown.

"These German guys reacted very quickly, but this was useless! Hurry up, throw a deep water bomb and kill these German guys!"

After receiving the order, the captain of the anti-submarine helicopter, Tian Tengfeng, flew towards the enemy submarine as fast as possible.
Chapter completed!