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

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

The connectors between the four boosters and the core stage have also withstood the simulation test. Thousands of tons of thrust are acting on the mechanism that needs to be separated. This is unprecedented in the history of China's aerospace industry.

Busy but not chaotic, running steadily and quickly, this is the true portrayal of the space agency at present, but NACA has encountered 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 space? The main power is the three RS25 hydrogen-oxygen engines at the tail of the space shuttle. Then the space shuttle lies on the orange fuel tank, and a solid propeller is placed on each side of the fuel tank.

The SLS rocket cancels the space shuttle, moves the engine under the fuel tank, changes three RS25s to four, and also bundles two solid rocket boosters. This is the SLS rocket.

It sounds like it is a modification based on a mature design. It should be very easy, very easy, and very cost-effective, right?

Theoretically yes, NACA thinks so too.

But they forgot one problem. The space shuttle is hung on the side of the 8.5-meter-diameter fuel tank. When the latter was designed, it was mainly considered to withstand the side pull force, and the vertical bearing capacity was not involved.

When the SLS rocket was officially manufactured, NACA discovered that if the previous fuel tank was completely used, the axial strength would not be enough, and strengthening it on the original basis would not work.

The only way is to make a new rocket body. Apart from looking the same as the original 8.5-meter orange tank, it is actually completely redesigned.

There is no technical problem, but there is a time problem. If we do this, we may not be able to make it in time for the first flight at the end of this year.

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

After Director Claire confirmed the strength problem of the core level, he held several demonstration meetings, but failed to make the original orange can reach the strength standard and decided that it could only be remade.

But it is impossible to postpone the launch. The launch in December 2016 is already later than the newly manufactured Long March 10 by the Chinese counterpart. If it is later, it will make people laugh.

In the end, after a long discussion, Claire and the engineers decided to use more budget to improve efficiency and use three or even four shifts to manufacture the new rocket body non-stop. Not only must the new rocket body be manufactured within 2 months, If it is built, it must be first fired as early as December.

This means that, including the test prototype rockets, the workload of manufacturing two SLS rockets must be completed in the remaining five months.

The manufacturing cost of the first SLS rocket is expected to increase from US$400 million to US$800 million. Fortunately, the allocation is sufficient, and Clare approved it without hesitation.

Information about the defects of SLS is tightly blocked, and little is known to the outside world. Now everyone's attention is on the Xinyuan-3 rocket launched on June 25.

Among the several research institutes of the National Space Administration, the First Institute saw Xinyuan 3 silently carrying out the original design of the Long March 9, the Sixth Institute had already started pre-research on YF135, and only the Fifth Institute had a different style of painting.

There is another stack of plans on the desk of the space agency boss.

They range from 10,000-ton space power stations to deep space spaceships. The most exaggerated one is the super space station they call "Tai Tian Ting".

The design of "Tianting" is worthy of its name. It is a super centrifugal space station with a rotation radius of 240 meters, rotating at 1.5 rpm, and can generate 0.6G gravity. It is much more spectacular than the Advance.

And unlike Qianjin, the cabin of "Tianting" is a ring-shaped part, connected internally. Tianting has two rings with a square cross-section and an inner ring radius of 47 meters, which generates 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. It is expected to be completed using 50 Xinyuan-3 rocket launches...

After searching for a long time, I finally saw something practical: a 100-ton super-large lunar surface base launched to the moon, which can accommodate 10 people for long-term stay.

Throw away all but this one.

…

"Liquid oxygen kerosene... why don't you use a methane generator? There is no carbon deposits yet. Xinyuan's high-thrust methane generator technology is fine!"

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

Xinyuan's three series of heavy/giant rockets, Xinyuan 2 methane engine, Xinyuan 3 kerosene engine, and Xinyuan 4 hydrogen and oxygen engine.

From an engine technology perspective, there are completely three routes, and these three engines with different thrusts can actually be simplified into three thrust section engines on one route.

Opening three lines at the same time is an extraordinary feat.

Lin Ju knew why. Of course it was possible to unify these three engines, but each of the three routes had its own advantages. Which one to choose was decided based on the usage. Anyway, all the technologies were available, and there was no crisis that conventional companies might fall into R\u0026D failure.

The M220 liquid oxygen methane engine relies on dual low-temperature fuels and can easily use a common bottom tank to reduce the dead weight of the rocket. Methane burns very cleanly. The engine is easy to clean and the fuel is not expensive. It is used in the new Far-Earth II, which has a particularly large number of launch missions. The number series is suitable.

The K380 kerosene engine cannot have a common-bottom tank due to its fuel characteristics, and it is necessary to clean the carbon deposits in the engine pipeline after each reuse. However, the specific impulse is higher. For a giant rocket like Xinyuan 3, the cost is not bad. Why not increase the transport capacity? This has allowed it to reach a load factor of 4.2%, while the old Changwu was only 2.9%!

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

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

The continuous operation of three engine technology lines with excellent performance is unprecedented in the world.

In the space race of the last century, NACA mainly promoted high-performance hydrogen-oxygen engines, which were expensive and had excellent performance. The space shuttle program was not so much about recovering the launch vehicles as it was about recovering the three extremely expensive RS25 hydrogen-oxygen engines at the tail of the space shuttle. .

One unit costs US$50 million, which was US$50 million in the last century!

The alliance relies on its advantages of abundant oil resources and uses high-quality sulfur-free kerosene to vigorously develop high-performance liquid oxygen kerosene engines.

NACA once wanted to develop a liquid oxygen kerosene engine, but the difficulty it encountered was that the sulfur compounds in the kerosene were difficult to separate and the impurities were too many and the combustion was unstable. They tried many methods but could not purify them. The alliance directly selected high-quality kerosene, which made Ami jealous. .

Due to its late start and lack of technical strength, China started from imitating the Alliance's YF1 and developed the YF20/21 series, the main engine of the last century and even now. The main engines of the Long March 2, 3, and 4 rockets use partial 2 Methylhydrazine-nitrous tetroxide fuel;

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

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

Xinyuan Aerospace Power: I want them all.

Tang Weitian was greatly shocked by this exaggerated technical strength and confidence.