The H80, which is more suitable for a three-stage engine than the H50, also ushered in the first practical test at this time.

The numerical suffix of the H80 is ground thrust, which can reach 112 tons in vacuum, which is almost equivalent to the Saturn V's second-stage rocket engine J-IIB.

On August 14, two days after the launch of the Long March 10, a Xinyuan-3 was erected at the No. 2 station of the Xinyuan Space Launch Site.

This Xinyuan No. 3 is only equipped with a second stage, and this second stage is the second stage that Guo Shen said can be recycled.

According to Guo Shen's previous idea, it squeezed an H80 engine improved from the H50 in the middle of the four H240s.

The appearance of the second-stage rocket is also very different, as the entire outer surface of the rocket has turned black due to the ablation of the atmosphere, which is a simplified layer of insulation from the H2 space shuttle thermal insulation tile.

As the object of protection has changed from humans to fuel tanks, the weight and cost of the insulation have been reduced considerably, but it still meets the requirements of resisting 100 ablations of the atmosphere.

At the same time, because of the increase in dead weight, in order not to reduce the capacity, the rocket body of the second-stage rocket was slightly lengthened by 5 meters to accommodate more fuel, and careful people can also find that there are a few more bulges in its lower part.

The recovery method of the second-stage rocket may not be the same as most people think, it is neither vertical landing gear recovery nor grille rudder recovery, but parachuting.

Because the diameter of 11 meters is too big, the arrow body is too wide and the center is just an H80 swinging around, the test of attitude control is ridiculously high, theoretically feasible, but in fact it is very troublesome, so it is not possible to fall vertically to the ground.

If multiple engines were to start recycling, the layout would have to be changed, and if three H80s were used, the second stage would have to change from four H240s to 13 H80s.

Not to mention the dead weight of too many engines, the oversized nozzle required for the vacuum version alone can't be squeezed, so it really can't be done.

And now the recycling method designed by Guo Shen is:

The two-stage rocket separated, and then the original top turned into a blunt round smooth surface, the head was obliquely downwards to resist the ablation of the atmosphere and protect the engine, and after entering the atmosphere, the parachute on top bounced off.

The purpose of this parachute is not to slow down, but to change the attitude of the head-down rocket to the engine down by gradually releasing the three parachutes and increasing them in turn.

Then there are four huge vents of the H240, each of which is stretched outwards to the maximum, leaving enough room for the H80 rocket engine to start rocking and decelerating, until it is nearly hovering at 5 to 10 meters above sea level.

At this time, the H80 suddenly shuts down, and at the same time, multiple small solid pulse rockets buried underneath ignite, causing the rocket body to lie down horizontally.

At the same time, several bulges at the tail of the second-stage rocket cracked and popped out huge air bags, which naturally made the tail engine face up when the rocket fell into the water, and the rocket body faced down and the engine floated up on the water surface.

At this time, the tugboat wandering nearby rushed over, and dragged the rocket all the way back to the port on a chain to be recycled and reused.

The arrow body is not afraid of soaking in salt water, not to mention that there is a protective layer that can resist atmospheric ablation, and the engine is fine if it is stained with a little water, and it can be used after washing.

The biggest advantage of this recovery system is that it greatly reduces the mass of the landing part, because it is poured directly into the water, the impact of the rocket is very small, and the strength of the rocket body is fine if the second-stage rocket is not long.

In this way, you can save at least more than 100 million at a time, and the launch cost of Xinyuan No. 3 is on par with Xinyuan No. 2A, which is comfortable~

With such expectations, Xinyuan-3 flew to the sky with a black and recyclable version of the second-stage rocket.

After 350 seconds, the first-stage rocket of Xinyuan-3 separated into the recovery process, and the four H240s of the second-stage rocket worked for a short while, and after crossing the atmosphere, they turned around and began to recover.

From the outside of the atmosphere to the inner ring of the ionosphere, the engine cannot be started for braking, nor can it be pneumatically adjusted, and this period of time is simply hard burning.

When Guo Shen raised his head, he could see a dazzling meteor in the sky, that is, the second stage of Xinyuan-2, which was rubbing violently against the atmosphere at more than 30 times the speed of sound.

Then there were a few minutes of lost contact, after which the second stage rocket crossed the ionosphere and established contact with the ground.

Lin Ju is also actively learning from Lao Ma in this launch mission, and there is an official live broadcast of the unclassified mission every time like before, and this launch said that the second level will be recovered, and there are many viewers.

At this time, the live broadcast was only a camera on the ground, and there was only a meteor in the sky at this time, and no images could be transmitted back, only radio contact.

When entering the predetermined altitude, the head of the rocket, which fell almost head-down, bounced the first parachute, which was very small and fragile, and only had time to be disconnected by the high-speed air flow for a second.

But the attitude of the rocket has been adjusted a little, and immediately the second parachute also popped, and this parachute was shredded after working for more than 2 seconds.

After that, the third parachute was also the last to pop out, and although the rocket was still falling at high speed, it took 5 seconds for this parachute to almost correct its posture.

As the third parachute was also abandoned, the H80 engine officially began to fire intermittently, constantly adjusting its attitude.

At this time, the live broadcast screen still does not see the specific situation in the sky, only the gesture demonstration of the animation simulation.

As the altitude gradually decreased, until 5,000 meters, the magnified and somewhat blurred second-stage rocket could finally be seen in the picture.

Although its attitude was completely correct at this point, the descent rate was extremely high, nearly twice as fast as the recovery rockets in the past.

This is because it uses less fuel to reduce weight, anyway, it is recovered in the sea, and it is no problem to have a higher speed.

At an altitude of 1,000 meters, the H80 finally began to work continuously, and the engine accelerated by the System Research Institute was extremely reliable, and it was directly practical after only 10 cumulative 1800-second test runs.

After multiple ignitions and long working hours, YF77 directly cried and fainted in the toilet.

The height dropped little by little, and Guo Shen suddenly realized that something was wrong.

How is this white smoke?

Since the whole body is black, the white gas is particularly conspicuous when escaping from the bottom side of the rocket, and it is difficult not to pay attention.

Netizens in the live broadcast room don't know what happened yet, but the launch center has found an anomaly:

"The pressure of the oxidant tank has plummeted, and it is suspected that there are cracks in the arrow body!"

"01, 04 pressure sensor abnormal, fuel rapid reduction!"

"The oxidizer is depleted, the engine stops!"

In full view of everyone, the second-stage rocket, which had descended to an altitude of 200 meters, finally stopped escaping the white fog, and the H80 at the bottom directly stalled due to lack of fuel, and then the rocket fell straight down.

The rocket began to fall sideways, and according to the pre-command, the four airbags at the bottom quickly popped out, and the four huge white airbags wrapped the entire tail.

The second stage of the rocket enters the water at an angle of 80 degrees to the vertical plane with its head down but basically horizontally, making a huge splash over the sea, first bounced off under the reaction force for a while, and then finally floated on the surface of the sea because of the head of the airbag.

(End of chapter)