In previous times, submarines did not stay underwater all year round, most of the time they were on the water, and only after finding a target, would they carry out a diving attack.

Therefore, submarines are not structures that adapt to elongated water droplets underwater, and most of them are the same structures as surface ships, which are suitable for sailing on the surface.

Naturally, they are also armed with powerful deck guns.

After all, torpedoes are so valuable that many captains don't want to waste them, leaving them to use when they need them to do so.

In the early days of the Atlantic theater, German submarines would warn ships and wait for their crews to leave the ship before resurfacing to attack with deck guns. If the opponent is armed, the submarine will damage it with a torpedo and then clean up the mess with artillery.

During this period, their deck guns were of large caliber, mostly 88 mm and 105 mm.

The German Navy has achieved many victories with deck guns, in addition to sinking millions of tons of various merchant ships.

For example, the U-242 boat even shot down a Soviet plane with 88mm deck guns, and the U-134 also shot down a US Coast Guard airship with 88mm deck guns.

"U-130" destroyed the refinery and warehouses in Crussell with 105-mm deck guns in the Caribbean. "U-711" destroyed the Soviet radar stations "Pravoch" and "Prague Boentzga" with 88-mm deck guns.

However, with the continuous increase of the Allied anti-submarine forces, the German submarine forces were often threatened, and for them, as long as they were discovered, they were destroyed, so in the later period, the German submarine forces almost lost the opportunity to operate the deck guns, and accordingly, they also canceled the deck guns, which were no longer needed.

Now, Germany has not yet faced this threat, and it would be quite funny and exaggerated to equip a submarine with deck guns from the point of view of later generations, but when you think about it, it is the inevitable choice of the German Navy.

You must know that only nuclear submarines can attack the Arctic route, and when there is only one nuclear submarine, it is impossible for it to repeatedly cross the North Pole and return to its own port for replenishment.

Then, it is a good choice to use torpedoes to attack key targets and deck guns to attack secondary targets.

And on the other hand, the task of the deck gun has changed, it is mainly used for air defense.

It is absolutely self-defeating to let submarines and planes fight against each other, and the advantage of submarines is concealment, but in case of an accident, such as a problem with the reactor of a nuclear submarine or a failure of the oxygen production system, which leads to having to surface, there must be means of air defense, right?

Therefore, its deck guns are not large 88 mm or 105 mm deck guns, and it is not easy for such large guns to hide under the submarine's silencing tiles.

It is equipped with a rapid-fire 20mm Bofors gun, which can be used both in the air and at sea, and in the German army's equipment, it belongs to the role of a panacea, for example, in addition to its own anti-aircraft guns, it has also been widely improved into tank guns, aviation guns and so on.

Now, on submarines, it is also cleverly hidden in front of the conning tower.

Another reason for being able to do this was that the submarines of this era were almost all in a double-hull layout.

Inside is a pressure-resistant shell, which is used to withstand the huge pressure of seawater, and the inside of the pressure-resistant shell is the working environment of personnel.

The structure of the double hull is different, outside the pressure-resistant shell, there is also a non-pressure-resistant shell, with a distance of more than one meter in the middle, filled with seawater, and at the same time various external equipment can also be deployed inside, the advantage of this is that it greatly increases the anti-strike ability of the submarine.

For example, in the typhoon of later generations, there is more than two meters of seawater between the two shells, and when the other party's torpedo comes and explodes outside, it can only damage the non-pressure-resistant shell outside, and it is almost ineffective against the pressure-resistant shell inside.

At the same time, it is also convenient to operate in areas like the Arctic, in case of encountering ice floe or something, you can carry it hard, and when it is critical, you can even break the ice directly on the Arctic Ocean.

Following Otto's order, the three sailors led by the second guard officer of the submarine stepped on the wet deck and came to the front of the deck gun.

Two men quickly turned up the deck guns, and the other two were responsible for disassembling the watertight shell box on the other side to complete the task of loading, and Otto looked at them from above and shouted: "Take the shield apart!" ”

In World War II, when German submariners used deck guns, some serious accidents occurred, that is, they exploded, which was completely caused by negligence.

The deck gun has to sail underwater with the submarine, even if it is sealed, it will enter the water, and the seawater is corrosive, so the muzzle of the deck gun is usually covered with a protective cover, which plays the role of sealing, and then opens it when it is used, but when the sailors operate, they always forget!

Under Otto's reminder, the second guard realized that he had made a serious mistake, and hurriedly stepped forward to remove the cover on the muzzle, and then, all preparations were made.

Let's fire!

"Tom tom!" The 20 mm deck gun is definitely not powerful enough, and against a cargo ship of tens of thousands of tons, it is like using a pistol against a tank.

If it were a warship, it would have taken a lot of artillery to sink it, but now all you have in front of you are cargo ships.

"Boom!" The armor-piercing incendiary bomb drilled into the belly of the cargo ship and immediately exploded a large hole, and the hull of the cargo ship could not withstand such an impact at all, and immediately broke a hole, and the sea water poured into it.

Alright, let's move on to the next one!

Almost every cargo ship was hit by only three shells, and the cargo ship was opened a big hole and slowly sank downward.

"Double car, full speed backwards!" Suddenly, Otto shouted loudly.

The two propellers in the tail immediately spun at high speed, dragging the 6,000-ton hull backwards, and just as they had just withdrawn a hundred meters, the cargo ship in front of them, which had just been hit, exploded violently.

"Boom!" The weapons carried inside were violently detonated, and on the surface of the sea, with it as the center, within a radius of several hundred meters, all there was terrible fire!

If the submarine hadn't retreated just now, I was afraid that it would have been damaged by the fragments that had fallen from the explosion at this time, and everyone was relieved.

Captain Otto's reaction was really too fast.

"Look, what's that?" An lookout shouted.

In the explosion, the cargo ship was completely torn apart, and the goods it was transporting were scattered on the surface of the sea, and in the distance there was a large cylindrical thing floating in the distance, which looked very much like the equipment of an oil refinery.