I ask you to build tractors, but you build rockets?

Beijing.

The Aviation Development Committee had just finished celebrating Dawn 3 when Lin Ju flew over in a hurry and asked to convene a standing committee meeting.

Since the boss also brought a few people to Huayin, there were not many people present, so Academician She was in charge for the time being.

"Xiao Lin, what do you need to confirm in such a sudden meeting? Why is it so urgent?"

Academician She has been very busy these days with matters related to the space agency, and he is still yawning now.

"I hope to finalize the lunar orbit lander as soon as possible. The original cooperation plan no longer meets future needs and should be abandoned."

"oh?"

Academician She raised his eyebrows. The Fifth Academy has been conducting research on the new reusable lander for two or three months and is about to enter the specific engineering design stage. Are you planning to overturn it now?

"The base believes that this small MTV is completely insufficient for future large-scale construction of the moon, and the rocket configuration is also not conducive to equipment transportation and loading. We simplified a configuration from that thing."

Lin Ju turned on the projector, and Academician She immediately recognized what the imagined image on it was: XN-90, but now the code name written on the PPT was "XH-40".

"The XH-40 (Hydrogen: hydrogen) landing spacecraft has an empty weight of 40 tons. It uses four 25-ton closed expansion cycle hydrogen and oxygen engines in the abdomen and two in the tail. It adopts the air tip working mode and has a vacuum specific impulse of 470 seconds;

The maximum take-off mass is 350 tons, the uplink payload is 220 tons, and the downlink maximum payload is 180 tons;

The width is 23 meters, the height is 39 meters, and the maximum height of the internal cargo compartment is 7.5 meters. "

Academician She also knew that the XN90 secret project was not too surprised by the appearance of the XH40, but others did not know that their eyes widened when they suddenly saw this thing that was completely contrary to mainstream aircraft.

It took a long time before someone spoke uncertainly:

"Vice Chairman Lin, is this...XH40 a little too radical?"

"Hiss, there was a movie three years ago... I remembered it. It was called "Interstellar". There was a lander in it that looked very similar to this thing. It also seemed to have a plug-type engine."

"The 470-second air tip engine and the carrying coefficient of 0.63 are indeed very good, but the dead weight is a bit high, and the dry mass ratio exceeds 10..."

"..."

Several other committee members started discussing spontaneously. Academician She was shocked and slowly thought of some benefits of this design.

The first is the landing attitude. Installing the engine part of the traditional lander at the tail will cause the payload part to be too high. It is still a small problem for personnel to climb up and down, but it is more troublesome for large equipment.

The XN40 is different. After landing, the tail or side hatch can be easily opened by pushing it with a trolley.

Another advantage is that the cargo bay is more square and efficient, and astronauts are more adaptable from the landing perspective.

Of course, the most important thing is the powerful carrying capacity. It has a carrying capacity of nearly 200 tons in both uplink and downlink, which is completely incomparable to traditional landers. The 6 volume-saving and high-impact hydrogen and oxygen engines are all installed outside and do not occupy the internal space of the spacecraft. , the powerful thrust of 100 tons in the vertical direction is also unprecedented.

Academician She approached Lin Ju and asked in a low voice:

"Any clues about XN90?"

Lin Ju: "The engine has to wait until next year, but the stress test of the prototype of the spacecraft is almost completed. This is a simplified and scaled-down version. Because it does not require atmospheric take-off, it is much more difficult and cheaper to manufacture. So let's build two verification machines first to practice. .”

"How long will it take to build the XH40?"

"It will be November. The engine is the same as the air tip of the TP-25. It can be used immediately after modification. The airframe can also copy the 90 design. In fact, the base has already started construction."

"..."

Good guy, construction of the base has already started before there is any result. Xinyuan's efficiency is indeed as high as ever.

At this time, the other committee members had almost finished their discussion, but they still had some questions.

An expert from one hospital raised his hand:

“Since the XH-40 uses liquid hydrogen and liquid oxygen fuel, how to solve the problems of volatilization and boiling of liquid hydrogen during long-term storage?

I think it should stay in orbit for a long time, which is a big problem. "

Lin Ju: "I think you should know a concept in the aerospace industry, zero evaporation storage technology."

Commissioners nodded. Any space agency using cryogenic fuel would be interested in the idea.

"Then what I want to say now is that Xinyuan has solved this technology. The first zero-evaporation liquid hydrogen storage tank has been installed on the fuel module of the 'Utu' space station and has been operating in the past half month. good performance."

"..."

Seeing the disbelieving looks of the committee members, Lin Ju coughed and continued:

"We have not applied for relevant patents, but we are open to customization within the Aviation Development Committee. This technology was developed by Serev and was just successful not long ago. I hope everyone will keep it as confidential as possible."

Academician She thought for a while. The power, body, and fuel storage were almost solved. Another important thing was the control... There is no doubt about Xinyuan's intelligent technology. Looking at it, the XH40 is unexpectedly mature?

But others are more surprised by the zero-evaporation storage technology that has emerged quietly. This concept has been extended from the last century to the present. It is hard to believe that it has been achieved so easily.

Being able to store liquid hydrogen for a long time is an amazing technology. The most popular fuel combination in the aerospace industry in the past two years is liquid oxygen methane. The reason is that its storage temperature is almost the same as that of liquid oxygen and it is easy to prepare.

But if liquid hydrogen can be stored for a long time, future deep space navigation can abandon the current normal temperature fuel combination and methane. The specific impact advantage of liquid hydrogen fuel is incomparable whether it is conventional power or nuclear power.

The committee is more interested in this technology than the XH40. To put it bluntly, the latter is just a special shape. Anyway, there is no atmosphere in space. Anything can be built, but the zero-evaporation storage technology is simply a big step forward for traditional aerospace. step.

Therefore, the controversy over giving the next-generation reusable lander to XH40 is much smaller, and basically no one objects.

However, Academician She kept Lin Ju alone after the meeting.

"Has your 25-ton closed expansion cycle engine been tested?"

"Of course, we directly dismantled the ready-made TP25 and modified it, conducted a test run within a week, and started building the official version this month."

Academician She nodded and then said:

"I want to give this engine the code name YF79-S."

Lin Ju was shocked: "But isn't Institute 101 still working on it? YF79 should be more than halfway done, right?"

"But this is a duplication of construction. They are all 25-ton closed expansion cycle hydrogen and oxygen machines. Yours still works in the gas tip mode, with a specific impulse of 470 seconds;

To be honest, the superiors are planning to separate some people from the Academy of Nuclear Science and send them to the space agency to set up a Nuclear Propulsion 110 Research Institute. The plug nozzle is more suitable for nuclear power, so they want to obtain some technology in this area from Xinyuan.

If the Sixth Institute can introduce this engine of yours and thoroughly understand it, it will avoid a lot of detours. Of course, you will not suffer any loss. Any conditions can be raised. "

Academician She said that she was a little embarrassed to say that after the emergence of H2, the Academy of Sciences believed that the era of chemistry had ended and that nuclear propulsion must be vigorously developed, so they prepared to build another nuclear propulsion institute under the framework of the space agency, and the starting point was very high, targeting NPAE. Joint working model.

The Nuclear Research Institute itself is confident, but Xinyuan is the world leader in the gas tip, and other countries are still having headaches about the instability of the gas tip engine.

Now it seems that this technology can be obtained through YF79S. It not only obtains a usable high-performance hydrogen and oxygen machine, but also obtains the desired plug nozzle technology.

Counting YF100K and YF77G, this is the third engine that the space agency has "converted" from private spaceflight.

Lin Ju immediately nodded and agreed without hesitation. The development center of the base is shifting to nuclear power, and the importance of traditional engines has become less and less.

Besides, is this another form of technology decentralization?

"Then we don't need money for this engine, let's change the conditions:

Mr. She, I want some high-power laser technology, and the smelting satellite light source is here. "

High power laser? Academician She thought for a while and nodded:

"Yes, in fact, the light source of the smelting satellite can be completely customized, but you can also research it yourself, but this thing is not easy."

Lin Ju looked very excited. Of course, the base did not actually need laser technology. It was just an excuse to use it in the future.