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

Chapter 224 Failure-II

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

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

On August 14, two days after the Long March 10 was launched, a Xinyuan 3 was erected at Station 2 of the Xinyuan Space Launch Site.

This Xinyuan-3 only carries a secondary stage, and this secondary stage is what Guo Shen calls a recyclable secondary stage.

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

The appearance of this second-stage rocket is also very different. Due to the ablation of the atmosphere, the entire outer surface of the rocket turns black. It is a heat insulation layer simplified from the heat insulation tiles of the H2 space shuttle.

Since the protection object has changed from humans to fuel tanks, the weight and cost of the insulation layer have been reduced a lot, but it can still meet the requirements of resisting 100 times of atmospheric ablation.

At the same time, due to the increase in dead weight, in order not to reduce the transportation capacity, the body of the second-stage rocket was slightly lengthened by 5 meters to accommodate more fuel. Careful people can also find that there are several bulges in the lower part of it.

The recovery method of the second-stage rocket may be different from what most people think. It is neither a vertical landing gear recovery nor a grid rudder recovery, but a parachute drop.

Because the diameter of 11 meters is really too big, the arrow body is too wide and there is an H80 swinging around in the center. The test on posture control is ridiculously high. It is feasible in theory, but in practice it is very troublesome, so I want to land it vertically. It won't work on the ground.

If multiple engines are to be started for recovery, the layout must be changed. If three H80s are used to achieve this goal, then the secondary engines will change from 4 H240s to 13 H80s.

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

Now the recycling method designed by Guo Shen is:

The second-stage rocket separates, and then the original top becomes a blunt and smooth surface, with the head tilted downward to resist atmospheric ablation and protect the engine. After entering the atmosphere, the parachute on the top bounces away.

The purpose of this parachute is not to decelerate, but to adjust the posture by gradually releasing three parachutes that become larger in sequence to change the head-down rocket to the engine-down position. After roughly adjusting, it is abandoned.

Then the four huge nozzles of the H240 were opened outward to the maximum, leaving enough space for the H80 rocket engine to start swinging and slowing down until it was almost hovering at 5 to 10 meters above the sea level.

At this time, the H80 suddenly shut down, and at the same time, multiple small solid pulse rockets buried below were ignited, causing the rocket body to lie sideways and fall down.

At the same time, several bulges at the tail of the second-stage rocket cracked and a huge air bag popped up. When the rocket fell into the water, it would naturally make the tail engine face up and the rocket body face down and the engine face up and float on the water.

At this time, the tugboat lingering nearby rushed over, put on an iron chain, and towed the rocket all the way back to the port for recycling and reuse.

The rocket body is not afraid of being soaked in salt water, not to mention it has a protective layer that can resist atmospheric ablation. It will be fine if the engine gets a little water, just wash it and use it.

The biggest advantage of this recovery system is that it greatly reduces the mass of the landing part. Because it falls directly into the water, the impact on the rocket is very small, and the strength of the second-stage rocket does not matter if it falls down for a long time.

Just like this, you can save at least more than 100 million. The launch cost of Xinyuan 3 is the same as that of Xinyuan 2A. It is comfortable~

With such expectations, Xinyuan-3 flew into the sky with a black recyclable second-stage rocket.

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

From the outside of the atmosphere to the inner circle of the ionosphere, the engine cannot be started for braking, nor can aerodynamic adjustments be made. This period of time is simply a hard burn.

When Guo Shen raised his head, he could see a bright meteor on the horizon. It was the second stage of Xinyuan-2. At this time, it was violently rubbing against the atmosphere at more than 30 times the speed of sound.

Then there was a few minutes of lost contact, and then the second-stage rocket crossed the ionosphere and established contact with the ground.

Lin Ju also actively learned from Lao Ma for this launch mission. As before, every non-confidential mission has an official live broadcast. This launch said that the secondary level will be recovered, and there were a lot of people watching.

The live broadcast at this time only had cameras on the ground, and there was only one meteor in the sky at this time. No images could be sent back, and there was only radio contact.

When it entered the predetermined height, the rocket head almost fell head-first and bounced off the first parachute. The area of ​​this parachute was very small and fragile. It only had time to be deployed by the high-speed airflow for a second before it disconnected. Far.

But the attitude of the rocket had been adjusted a little, and the second parachute immediately popped up. This parachute worked for more than 2 seconds and was torn into pieces.

After that, the third parachute was also the last one to pop up. Although the rocket was still falling at a high speed, under the influence of this parachute, it took 5 seconds to almost straighten its posture.

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

At this time, the live broadcast still cannot see the specific situation in the sky, only the animated simulation of the posture demonstration.

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

Although its attitude has been completely corrected at this time, its descent rate is extremely high, almost twice as fast as previous recovery rockets.

This is because it carries less fuel to reduce weight. It is recovered at sea anyway, so a higher speed is no problem.

Entering an altitude of 1,000 meters, the H80 finally began to work continuously. This engine accelerated by the Systems Research Institute's funds was extremely reliable, and it was immediately practical after only a total of 10 1,800-second test runs.

After igniting multiple times and working for a long time, YF77 cried and fainted in the toilet.

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

Why is there white smoke?

Because the whole body is black, when the white gas escapes from the bottom side of the rocket, it is particularly conspicuous, and it is difficult not to notice it.

Netizens in the live broadcast room still don’t know what happened, but the launch center has discovered anomalies:

"The pressure in the oxidizer tank dropped sharply, and it is suspected that the rocket body has cracks!"

"01, 04 pressure sensors are abnormal, fuel is decreasing rapidly!"

"Oxidant exhausted, engine shut down!"

In full view of everyone, the second-stage rocket that had dropped to an altitude of 200 meters finally stopped emitting white mist. The H80 at the bottom stalled due to lack of fuel, and then the rocket fell straight down.

It was detected that the rocket began to fall sideways, and the four airbags at the bottom quickly popped out according to the advance instructions. Four huge white airbags wrapped the entire tail.

The second-stage rocket entered the water head-down at an angle of 80 degrees to the vertical plane but basically entered the water horizontally. It made a huge splash on the sea. It first bounced up for a while under the reaction force, and then finally floated on the sea surface because of the airbag head-down. superior.