Galaxy Technology Empire

Chengdu, Chengdu Aircraft Corporation.

J-20 improvement project.

As the person in charge of this project, Yang Dacheng was discussing with a group of researchers from Dongtang Aerospace Group, and many people from Galaxy Aerospace Industry Group were also there.

The reason why people from the aerospace system are here is mainly the result of Chengdu Aircraft Corporation's imagination, and the rocket engine was installed on the J-20.

"General Engineer Yang, we have already got the engine you want." Huang Qinxue from Dongtang Aerospace Industry Group handed a document to Yang Dacheng.

"Oh! It's great. We have everything ready now. All we need is Dongfeng. Have you brought your engine?" Yang Dacheng asked quickly while looking through the documents.

Huang Qinxue pointed to the container not far away and said: "I brought it with me. There are four in total. However, the power of the rocket engine is very powerful. Can the J-20 body withstand it?"

"We have modified and strengthened it. We have used a lot of carbon nanotube composite materials. The empty weight of the aircraft is lighter than before. Now it depends on your engine." Yang Dacheng said.

This is the driving effect of a large-scale system project. In fact, during the development process of mass projectors and spacecrafts, the aerospace system will produce some technologies that can be applied in other fields.

As the aviation system closest to the aerospace system, they are the first to be exposed to technological radiation. The two have many technologies in common.

For example, the reusable hydrogen-oxygen engine on the spacecraft, the anti-radiation interference technology on the spacecraft, etc. These technologies can all be applied to aircraft.

After Yang Dacheng finished flipping through the documents, he turned around and told his assistant: "Have someone pull the container inside and prepare to install the engine."

"Okay." The assistant quickly went to arrange this matter.

"I asked Mr. Yang why you are in such a hurry. It will take at least two or three days to install the engine on the J-20. Why don't you invite me to your canteen for dinner?" Huang Qinxue joked, pointing to his watch.

When Yang Dacheng saw that the time was already 12:24, he immediately reacted: "I was negligent. Make arrangements for dinner immediately."

"Then I'm welcome." Huang Qinxue said with a smile.

"As long as you don't mind Cheng Fei's messy meal in the cafeteria." Yang Dacheng said while leading the way.

As Huang Qinxue was walking, he suddenly remembered something. He took out a list from his briefcase and handed it to Yang Dacheng: "But it's a waste of money. We have to reimburse you for the four engines."

"Haha, it will definitely be reimbursed." Yang Dacheng accepted the list with a smile.

Although both parties are state-owned enterprises, the brothers have settled the accounts. The total cost of the four engines is as high as 60 million yuan. Of course, these are the first batch of manufacturing and include a large proportion of research and development expenses. If it enters the stage of large-scale mass production, , the cost of one unit may be around 2 to 3 million Chinese yuan.

The structure of rocket engines is relatively simple and rough compared to turbofan engines. Coupled with the various new technologies and new materials currently used in spacecraft, it is even more simple and rough.

Yang Dacheng took Huang Qinxue and others to dinner, while the container was pulled into Chengdu's aircraft assembly workshop.

In the huge assembly workshop, many workers and researchers are busy, and a J-20 without an engine is parked quietly in the assembly workshop.

Since the hydrogen-oxygen engine needs to be modified, it is not only a matter of replacing the engine system, but also the fuel system.

The fuel used in domestic hydrogen-oxygen engines is hydrogen solid fuel, and the J-20's fuel tank has a volume of 12.8 cubic meters and can store up to 10 tons of aviation kerosene (the density of aviation kerosene is 0.78 tons per cubic meter).

12.8 cubic meters of hydrogen solid fuel (the density of hydrogen solid fuel is 0.47 tons per cubic meter) reaches about 6 tons.

The calorific value of general aviation kerosene is 41840-42890 kilojoules per kilogram, wide-cut kerosene can reach 42890-43510 kilojoules per kilogram, and aviation gasoline is greater than 43090 kilojoules per kilogram.

The calorific value of hydrogen solid fuel is 129,000 kilojoules per kilogram, which is about three times that of aviation kerosene.

Theoretically, each kilogram of submetallic hydrogen can provide three times the power. As for why not use the same hydrogen and oxygen solid mixed fuel as the spacecraft.

There are two reasons for this. The first is that aircraft mainly fly in the troposphere or stratosphere of the atmosphere, where oxygen exists; the second is that the use of hydrogen and oxygen solid mixed fuel will reduce the overall calorific value, because hydrogen and oxygen The calorific value of solid mixed fuel is 14,300 kilojoules per kilogram.

Why the calorific value of hydrogen-oxygen solid mixed fuel has dropped so sharply is mainly because the specific gravity of submetallic oxygen has increased, which reduces the specific gravity of submetallic hydrogen itself as fuel.

Theoretically, 10 tons of aviation kerosene can provide 430 million kilojoules of heat, while 6 tons of hydrogen solid fuel can provide 774 million kilojoules of heat.

In other words, after switching to a hydrogen-oxygen engine, the cruising range can be increased by 1.8 times while the engine power and fuel tank remain unchanged.

The J-20 has a maximum range of 5,500 kilometers and a radius range of 2,000 kilometers. After switching to a hydrogen-oxygen engine, the maximum range can be increased to 9,900 kilometers and the radius range can be 3,800 kilometers.

There is another advantage that cannot be ignored, that is, the weight has become lighter. After 10 tons of aviation kerosene is converted into 6 tons of hydrogen solid fuel, there is an additional 4 tons of payload.

"Gong Zhang, the engine is here." A staff member shouted to Zhang Weiting, the engineer in charge of assembly.

William Zhang immediately put down what he was doing: "Get the engine out."

"OK."

After a while, two special hydrogen-oxygen engines (the J-20 has twin engines) were gently picked up and placed on a workbench by a crane.

"Add the weight of the two engines to the data and see what the overall weight is?" Zhang Weiting ordered.

The researcher quickly calculated, and soon the data was calculated.

"Gong Zhang, the overall weight of the empty machine is 15.7 tons."

Zhang Weiting raised his glasses and remembered this data. The original design of the J-20 was 19 tons when empty, the maximum fuel loading capacity was 10 tons, and the maximum payload was 8 tons.

After the improvement, the J-20 has an empty aircraft weight of 15.7 tons, a maximum fuel loading capacity of 6 tons, and a maximum payload of 15.3 tons.

However, considering that the pilot's cockpit needs to be converted into a load-resistant liquid tank, the weight may need to increase by about 1.5 tons.

The final payload will be between 13.5 and 13.8 tons.

This improvement is simply a qualitative change. If the fuel loading capacity is increased, the maximum range may be increased to more than 10,000 kilometers, and the radius range can reach between 4,000 and 5,000 kilometers.

"Get ready for the installation work immediately." Zhang Weiting ordered.

"Okay." The engineers and workers in the assembly workshop jumped into action.

After Zhang Weiting ordered the engine installation work, he went to the workshop on the side, where the anti-ghosting life-sustaining warehouses produced by Shanmei Anti-Ghosting Warehouse Company were displayed. Chengdu Aircraft Group's aircraft-specific anti-ghosting life-sustaining warehouses are specially customized. Version.

The reason for using the anti-gravity life tank is mainly because the J-20, which uses a hydrogen-oxygen engine, is very fast and is very likely to exceed 10 times the speed of sound.

In this case, the overload that the driver needs to withstand will be very terrifying, and may reach as much as 20 or 30 G in an instant.

The anti-load technology of the spacecraft can just solve this problem.

The aircraft exceeds 10 times the speed of sound, which is faster than most rockets. Obviously, this magical modification of Chengdu Aircraft Group has brought about a qualitative change in the J-20.

If some systems are modified, it can even be used as an aerospace plane. Of course, due to the existence of the mass projector, the importance of the aerospace plane is no longer great.

After all, no matter how powerful the aerospace plane is, it can't defeat the planetary orbital gun in synchronous orbit.