Planet Construction Engineer's main text volume Chapter 182, 183 This is not the exercise Busan, Goryeo's first port and second largest city, and once one of the busiest ports in the world.

But at this time in Busan, there was no freighter passing by at the port; there were no congested streets in the city; there were no noisy crowds in the high-rise buildings.

Instead, there are various warships, armored vehicles, ground artillery, and temporary military fortifications.

The crowd had already evacuated to the nearby area, which was about to become a battlefield for humans and Zergs.

The world's vision is gathered here again, and the last failure happened one day ago.

The industrial strength of Sakura Country is stronger than that of Goryeo. Even with the help of Baiying, can they really defend it?

In the combat command center, the commanders are urgently discussing countermeasures. The experience of another war yesterday can be used immediately today.

How to block the attacks of the three types of beetles has become the key point they discussed.

"The beetle defense is amazing. In close-range offensive and defense battles, tank armor-breaking bombs and armor-piercing bombs have more lethality to beetles than short-range missiles. We need to reserve armor-breaking bombs and armor-piercing bombs in large quantities."

...

He Xingzhou did not pay attention to this war because the insects were also approaching the Demon City. At the current speed, they could reach the city within fifteen days!

At this time, most of the steel Great Wall in the Magic City section had been built, and it should be barely completed in fifteen days.

This is not enough!

Thousands of red beetles, green beetles, and one hundred black beetles, with mutated creatures, broke through the defense of the slash zone.

What if there are more Zergs coming to the Demon City, what will be stronger?

"The Great Wall of Steel blocks mutated creatures and level one, and level two Zergs are not a problem." He Xingzhou thought, "The third Zerg is somewhat difficult. Level four and level five Zergs, such as the black beetle. It may not be possible to rely solely on cannonballs and missiles!"

"In case there are other more advanced Zergs... the risk is too great! Weapons and equipment must be improved as soon as possible."

The development of weapons in the Xuanwu Project has already begun. He Xingzhou originally wanted to improve laser weapons first, but the appearance of beetles changed his mind. He wanted to improve the electromagnetic cannon first!

Laser weapons and electromagnetic weapons have different advantages. Suppose they fight against level 5 black beetles, laser weapons need to burn them for several seconds before they can burn them to death.

The kind of laser weapon that can instantly evaporate it is naturally impossible to create now.

The electromagnetic gun can obtain great kinetic energy in a very short time, and even a 50-meter-thick steel plate can make a big hole! It explodes instantly, while the laser weapon is more like continuous output.

"In coastal defense battles, although laser weapons have a long attack distance, they are easily affected by sea water and weather, and cannot kill beetles instantly; in contrast, electromagnetic cannons are now more lethal to beetles."

He Xingzhou analyzed and decided to improve the electromagnetic cannon first.

He called out the quantum optical brain and opened the weapon technology tree.

"Unlocking the basic induction electromagnetic gun requires 300,000 units of energy."

"Unlocking the basic electromagnetic railgun requires 500,000 units of energy."

"Unlocking the basic plasma electric heater requires 700,000 units of energy."

"Unlocking the basic electromagnetic reconnect cannon requires 1 million units of energy."

The basic induction electromagnetic gun has mastered relevant technologies in Shenzhou. He Xingzhou directly entered the information and has unlocked it.

However, this electromagnetic gun is fixed in the barrel with an acceleration coil. When it passes through an alternating current, the generated alternating magnetic field will generate an induced current in the projectile coil. The magnetic field of the induced current interacts with the magnetic field of the acceleration coil current, generating an electromagnetic field force, causing the projectile to accelerate and move and emit it.

The electromagnetic rail gun is laid with electromagnetic guide rails. After the current is applied, the guide rails generate a strong magnetic field. Under the action of ampere force, the projectile will be emitted at a large speed, and in theory can even reach the sub-light speed.

The electromagnetic railgun has a strong lethality, but if it is to manufacture now, it will face a problem, that is, its super high lethality and requires a longer acceleration track.

Plasma electric heater uses high-pressure plasma heating to push the shell forward.

As for the final electromagnetic reconnection cannon, its principle is the same as that of a coil cannon, except that it uses another method of continuous reconnection.

It combines the advantages of coil guns being able to fire large-mass projectiles and rail guns being able to fire ultra-high-speed projectiles, and can give the shell a higher acceleration peak, making it more powerful!

At present, the mainstream in the world are induction electromagnetic guns and electromagnetic rail guns, and there is no mature electromagnetic reconnection gun.

He Xingzhou unlocked all four types of electromagnetic guns in one breath. The use scenarios of these electromagnetic guns are different. Without saying that one is stronger than the other, but the manufacturing difficulty is different.

In the current situation, the most suitable one is the electromagnetic reconnect cannon, which is stronger and does not need to be made of ultra-long electromagnetic tracks for the time being. Its turret is a rectangular structure that can be manufactured in a short time.

Recently, the unit energy of quantum optical brain is sufficient, because a nuclear power plant has been built on the Great Wall of Steel, and He Xingzhou has obtained a new source of energy.

He Xingzhou digested and understood this information, and directly contacted the Electromagnetic Weapons Research Institute in the cloud, bringing the team responsible for researching electromagnetic guns into the channel.

"Everyone, I have found a way to design an induction electromagnetic gun!" He Xingzhou said.

"What method?" Bao Xiangbei, the team leader, asked. He is an electromagnetic weapon expert and has led the team to design a variety of electromagnetic weapons.

He Xingzhou said: "The two positions are designed to be composed of upper and lower rectangular coaxial coils, with a gap between them. The emitter is a rectangular body, which can pass through the gap between the two coils for accelerated movement."

"Because the projectile has a continuous current, the magnetic field generated by the projectile seems to "cut off" the magnetic field of the acceleration coil when it passes through the acceleration coil, and then it is very abstractly reconnected to the next coil magnetic field."

"In this repeated reconnection process, the projectile is continuously accelerated, and the advantages of induction electromagnetic guns and electromagnetic railguns are obtained at the same time!"

Everyone understood the principle, and He Xingzhou sent a structural diagram he designed.

This is a columnar electromagnetic reconnect cannon, which mainly contains a columnar armature, which is wound by a columnar asynchronous induction coil.

By controlling the current, the effect of electromagnetic acceleration and magnetic field reconnection is achieved.

"If we can accurately control each reconnection in this design, the projectile can be continuously accelerated within a small volume, and finally achieve the same effect as the ultra-long-distance electromagnetic rail gun!" Bao Xiangbei said, "We must try it immediately!"

He Xingzhou said: "It is best to make the sample immediately. If the test is successful, mass production will be sent to the front line immediately!"

Bao Xiangbei also knew that it was a time war and needed to race against time.

He immediately said: "We will start now, and once the test is successful, start manufacturing immediately!"

...

While they were studying electromagnetic reconnection guns, the battle in Busan had already begun.

The previous process is similar to that in the Sakura Island Tsubasa area. The Zerg first uses low-level mutant creatures to attract artillery fire. After the consumption is almost done, they will send beetles to land.

Because of their previous experience, they did not feel so embarrassed this time.

The specially equipped tank armor-piercing bombs and armor-piercing bombs caused a lot of damage to the beetles, but when the black beetles landed, the tank armor-piercing bombs and armor-piercing bombs also had limited damage to them.

At the mouth of the sea, the Zerg attacked the fleet and several warships were destroyed.

"Stick for another half an hour, the mutant creature will almost die!" Commander Kim Sung-hwan shouted in the command center.

"We must defend the coastal defense line!"

Half of the first batch of black beetles that landed were killed by them, and less than fifty were left. If they survived, they would still have a chance to keep them.

But something desperate happened. They originally thought that there would be only a group of black beetles, but new big black spots appeared in the ocean, and more black beetles appeared. There were various red beetles and green beetles behind them, which were estimated to be six or seven thousand.

That scene was like countless heavy armored vehicles, charging and defensive lines!

Underwater, the giant Zergs are also striking the defense line.

The drone photographed that a tentacle that was dozens of meters long appeared in the water, tied up a small ship and pulled it directly into the sea!

"Boom!" A Tomahawk cruise missile hit it, and a large piece of scarlet appeared in the ocean, but the guy did not float up, but disappeared into the water.

In the deep water, monsters crazily hit the underwater interceptor network, and some of them can also bring their own current. The interceptor network has collapsed and the estuary has been broken.

The White Eagle's commander looked at the defense line and said, "Let's retreat, our missiles are ready."

"Retreat!" After Kim Sung-hwan gave the order, he seemed to have lost his strength.

This is Busan! Unlike the Sakura Island Tsuko District, even if you retreat to the land defense line and blow all the beetles to death, the city will suffer heavy losses!

Moreover, the monsters have opened the estuary, and starting from the Luodong River, they will enter the island.

Even greater disasters and chaos are coming!

Their soldiers retreated to the land defense line, and countless missiles fell, blowing up the Zerg around the coastal defense line!

Assimilated to ashes, there is the first port on the once prosperous island!

"Busan has fallen!" At this moment, countless islanders were crying.

"Our home is gone!"

"The Zerg has entered the river and will go directly to the inland!"

"What should we do in the future?"

No one can give the answer... After surviving with broken arms, they are more confusion and fear!

...

"Two times, two times of coastal defense, all failed!" The entire human world was shocked by this!

Although these two places are not large in size, they are both top industrial and technological powers in the world.

With their military strength, they cannot defend the estuary in front of the Zerg.

If the Zerg landed from other places, can they keep it?

Pessimism spreads in human society, and some people even begin to feel despair, proclaiming the arrival of the doomsday, expressing their desire to give up resistance, or go to heaven in advance before the Zerg arrives.

Some people began to indulge themselves. Instead of being wiped out by the Zerg, it would be better to be happy before they die.

Some people and organizations have also begun to call on all mankind to unite to resist the Zerg! Develop more advanced military technology, etc.

Various phenomena emerge one after another.
To be continued...