The Long March 10 team has not encountered any major problems except for being busy, after all, the 5-meter rocket body technology of Chang 5 is not complicated, and it has been successful for so many years.

The four boosters and the connector of the core stage have also withstood the test of simulation, and the thrust of several thousand tons is applied to the mechanism that needs to be separated, which is unprecedented in the history of China's aerospace.

Busy but not chaotic, steady and fast, this is the true portrayal of the space agency at the moment, but NACA is in trouble.

The trouble is the SLS rocket.

The SLS rocket originated from the STS, the Space Shuttle program.

How did the space shuttle get into the sky? The main power was the three RS25 hydrogen-oxygen engine engines in the tail of the shuttle, and then the shuttle lay on the orange fuel tank, with a solid thruster on each side of the fuel tank.

The SLS rocket is to cancel the space shuttle, move the engine under the fuel tank, change the three RS25s to four, and also bundle two solid rocket boosters, this is the SLS rocket.

It sounds like a change in a mature design, and it should be very easy and cost-effective, right?

Theoretically, yes, and that's what NACA thinks.

But they forgot that the shuttle was hung on the side of an 8.5-meter-diameter fuel tank, which was designed to withstand the tension of the side, and did not involve the vertical bearing.

When the SLS rocket officially began to be manufactured, NACA found out that if the previous fuel tank was completely appropriated, the axial strength would not be enough at all, and it would not be possible to strengthen it on the original basis.

The only way to do this was to create a new arrow body, which was completely redesigned, except that it looked the same as the original 8.5-meter orange can.

Technically, there is no problem, but there is a problem with the timing, and if this is done, it is likely that it will not be able to make the first flight at the end of this year.

It just so happened that at this time, Xinyuan No. 3 left the factory!

After confirming the strength of the core level, Director Claire held several demonstration meetings, but could not make the original orange can strength meet the standard, and it was decided that it could only be rebuilt.

But the launch delay is impossible, and the launch in December 2016 is already later than the newly built Long March 10 of its Chinese counterpart, and it will make people laugh if it is too late.

In the end, after a long discussion with the engineers, Claire decided to use more budget to improve efficiency, and use three or even four shifts to manufacture the new arrow body without stopping, not only to ensure that the new arrow body was built within two months, but also to make the first shot as early as December.

This means that, together with the test sample arrows, the work of creating two SLS rockets will have to be done in the remaining more than 5 months.

The cost of manufacturing the first SLS rocket is expected to increase from $400 million to $800 million, but the funding is still sufficient, and Claire does not hesitate to approve it.

News about the SLS flaw was tightly sealed and little was known to the outside world, and now everyone's attention is on the Xinyuan-3 rocket, which was launched on June 25.

Among the several research institutes of the space agency, the first academy saw that Xinyuan-3 was silently carrying out the original design of the Long March 9, and the sixth academy had begun the pre-research of YF135, only the painting style of the fifth academy was different.

On the desk of the space agency boss, there is another stack of plans.

From 10,000-ton space power stations to deep-space spacecraft, the most exaggerated is the super space station that they named "Taitianting".

The design of the "Heavenly Court" is worthy of the name, it is a super large centrifugal space station with a rotation radius of 240 meters, rotating at 1.5 revolutions per minute, and can produce 0.6G gravity, which is much more spectacular than the Advance.

And unlike the Advance, the cabin of the "Heavenly Court" is a circular part of a circle, which is internally connected, and the Heavenly Court has two rings, with a square cross-section, and an inner ring radius of 47 meters, which produces 0.12G gravity and can be used as a microgravity laboratory.

The overall mass is as high as 9,000 tons, and the full load operation is tens of thousands of tons, and it is expected to be completed with 50 Xinyuan-3 rocket launches......

After turning over for a long time, I finally saw a practical point: launching a 100-ton super-large lunar base to the moon can meet the long-term stay of 10 people.

Throw away all but this one.

……

"Liquid oxygen kerosene...... Why don't you use a methane machine? There is no carbon deposit, Xinyuan's high-thrust methane machine technology can! ”

Tang Weitian, who had just completed the first four days of preparatory training before training, also came to Qiongzhou, and looked at the Xinyuan-3 giant rocket that was so tall that he felt that the assembly building could not fit it.

Xinyuan's three series of heavy/giant rockets, Xinyuan No. 2 methane engine, Xinyuan No. 3 kerosene engine, and Xinyuan No. 4 hydrogen and oxygen engine.

From the engine technology point of view, there are completely three routes, and these three engines with different thrust can actually be simplified into three thrust section engines of one route.

Opening three lines at the same time is not ordinary.

Lin Ju knows why, of course these three engines can be unified, but the three routes have their own advantages, and what is chosen is decided according to the use case, anyway, the technology is all there, and there is no crisis that conventional enterprises may fall into R&D failure.

The M220 liquid oxygen methane engine, relying on double cryogenic fuel, can be easily applied to the common bottom tank, reducing the dead weight of the rocket, the methane burns very clean, the engine is clean and easy, and the fuel is not expensive, which is very suitable for the Xinyuan-2 series with many launch tasks.

K380 kerosene engine can not do a common bottom tank due to fuel characteristics, and after each reuse, it is necessary to focus on cleaning the carbon deposits of the engine pipeline, but the specific impulse is higher, for a giant rocket like Xinyuan 3, the cost is not bad, it is better to increase the capacity, which makes it reach a load factor of 4.2%, and the old long five is only 2.9%!

The Xinyuan-4 super-giant rocket is even more exaggerated, and now the newly changed configuration core stage uses 39 H240 liquid oxygen and liquid hydrogen engines, which have the largest specific impulse advantage and a load factor of about 5%!

After explaining the reason, Tang Weitian could only nod with a heavy face.

Three lines of engine technology with excellent performance in a row are unprecedented in the world.

In the space race of the last century, NACA mainly promoted high-performance hydrogen-oxygen engines, which were expensive and high-performance, and the space shuttle program was not so much to recycle the launch vehicle, but to recycle the three extremely expensive RS25 hydrogen-oxygen engines in the tail of the space shuttle.

$50 million for one piece, that's $50 million in the last century!

The alliance relies on its own advantages of abundant petroleum resources, plays the role of high-quality sulfur-free kerosene, and vigorously develops high-performance liquid oxygen kerosene engines.

NACA once wanted to develop a liquid oxygen kerosene engine, but the difficulty encountered was that the sulfide in the kerosene was difficult to separate, there were too many impurities, and the combustion was unstable, and it was impossible to purify it after thinking of many ways.

Due to its late start and lack of technical strength, Huaguo started from imitating the YF1 of the alliance, and developed the YF20/21 series, the main engine of the Long March 2, 3 and 4 rockets, using dimethylhydrazine-nitrogen tetroxide fuel;

Later, at the end of the century, the YF100 technology line was opened by imitating the former Alliance RD120 liquid oxygen kerosene engine.

Private companies, represented by Blue Origin and SpecaX, bet on liquid oxygen methane engines.

Xinyuan Aerospace Power: I want them all.

This exaggerated technical strength and self-confidence shocked Tang Weitian greatly.

(End of chapter)