Although it is just a 150 kilogram engine.

But the thrust reached fifty-five tons.

The thrust-to-weight ratio has reached an astonishingly more than 360 (not counting as batteries).

The comparison even reached 48.

Data naturally blinds people's eyes.

Su Han is very satisfied with Feilong x2's data.

He plans to install the Flying Dragon x2 onto a second-stage rocket.

If three units are connected in parallel.

It can generate more than 160 tons of thrust.

Instead, use a chameleon battery.

The total weight of three engines and batteries will not exceed 200 kilograms.

Two hundred kilograms plus fuel, rocket shell, and fairing will not exceed seven tons.

Then there is another ten tons of effective load.

When the second-stage rocket arrived at the Carmen Line, the fuel was at least about 150 tons, and it also reached 100 tons in low-Earth orbit.

The famous Saturn V rocket has a capacity of only 118 tons to reach low-Earth orbit.

Although his own Rockets' capacity has not surpassed Saturn V.

But if you add the first-stage rocket, your total rocket mass is only 1,300 tons.

Saturn V is a super rocket of more than 3,400 tons.

And his own rockets are only 1,300 tons.

The rocket's fuel is 50% worse than that of Saturn V.

It shows your rocket technology.

It is already the world's most well-deserved number one.

Su Han was of course a little proud.

But he also knows.

This is just my wishful thinking.

The Apollo spacecraft carried by Saturn V does not need to be recycled.

And his own second-stage rockets are to be recycled.

I want to take back the thrown things.

It also consumes carrying capacity.

After calculation.

Su Han's second-stage rocket wants to enter geosynchronous orbit.

At least eighty tons of fuel are needed to accelerate.

Accelerate requires fuel.

Reducing speed requires fuel.

Although the fuel is not used up when decelerating.

But at least forty tons.

It takes ten tons to land.

Then the fuel alone costs 130 tons.

Plus the weight of the housing.

Want to create a recyclable secondary rocket.

The carrying capacity of the Earth's transfer orbit is at most about twenty tons.

In fact, most of the transportation capacity is consumed to accelerate and decelerate fuel.

The Rockets seemed to have a lot of transportation capacity, but they finally got lonely.

The key is that the fuel is used more.

The cost is also high.

A rocket of 1,300 tons.

The fuel must be at least 900 tons.

Although liquid oxygen is not expensive.

But methane is not cheap.

Now the market is at least 20,000 yuan per ton of methane.

Even if it is only one-fifth of the dosage.

It also costs 160 tons of methane.

Then the cost of methane alone will be more than four million.

Although this fuel fee is nothing to a second-stage rocket that can be recycled.

But the key to the problem is that the capacity has dropped too much.

Overall it's not cost-effective.

How to improve the capacity of the second-stage rocket while saving more fuel is what Su Han needs to solve now.

Su Han said: "Shenlong, how do you think we can complete the recycling of the second-stage rocket without consuming fuel?"

Shenlong said: "The launch vehicle is actually acceleration and deceleration.

In order to save fuel during the acceleration phase, you can only use the gravitational slingshot effect.

When it is time to accelerate, it will take a certain amount of time.

However, deceleration also consumes fuel, but the deceleration effect is different on different tracks.

Theoretically, the closer it is to the earth, the more obvious the rocket is affected by the earth's thin atmosphere. Over time, the rocket's speed will gradually decrease. As long as the time is long enough, it will drop below several thousand kilometers in the morning and evening, and finally land on the earth.

As for the length of time, it depends on the height of the rocket from the earth and the density of the atmosphere.

The atmosphere near the Carmen Line is only one thousandth of that of the Earth.

It will take several months to slow down at this height with the Rockets themselves.

It will take at least a few years to reduce the rocket to the speed of falling to Earth."

Su Han said: "Is there no other way?"

Shenlong said: "Another way is to use a speed reduction parachute to increase the windward area. Although the speed of the return rocket reaches twenty times the speed of sound, the gas outside the atmosphere is thin, so it doesn't matter if the speed reduction parachute is a little faster. However, the strength of the arrow body must be redesigned and the space for the speed reduction parachute must be accommodated, which may add additional weight.

If you do not use a speed reduction fan, you can use a speed reduction plate that can be retracted. Although the area is smaller, it can be more flexible as the airflow changes and reduce lift. However, the speed reduction plate is not strong enough and may be damaged when leaving the earth, which is also a problem.

If you can design a dynamically open and closed fairing, you can use the open fairing to slow down. This way you can recycle the fairing together. I just calculated that if you use a deformable fairing to slow down, it will take about ten days and the rocket will drop to a speed that can return to the earth."

Su Han said: "How much can the capacity increase?"

Shenlong said: "If the total mass of a rocket is 1,300 tons, the low-Earth orbit capacity is about 100 tons transfer orbit capacity is about 100 tons, and the geosynchronous orbit is about 50 tons. If the earth-moon transfer orbit uses the gravitational slingshot effect, it is probably the same.

Of course, you can also use the method of adding fuel in the air to reduce the speed. This is a method of rapid slowdown, but you need to prepare a rocket that can add fuel under different speed orbits, and reduce the speed by adding fuel in the air.

You can consider it when implementing the moon landing plan."

Su Han was very satisfied with Shenlong’s suggestions.

If the Shenlong’s suggestion can be achieved.

Then it is really possible to complete the recovery of the second-stage rocket without losing capacity.

That's true.

That's really a little fuel fee to recycle all the rockets.

Su Han immediately organized a team to develop a retractable fairing.

At the same time, it began to develop recyclable secondary rockets.

...

November.

China's domestic mobile phones are fully committed to the Qianglong battery.

It is a siege in the world.

The cheapest Qinglong mobile phone abroad is also sold for over 3,000 meters of gold.

Foreign users can't afford such a high price.
To be continued...