On September 13, the official Weibo of the Aviation Development Commission released the launch notice of the Wentian and Mengtian experimental modules on September 19 and 20.

The space agency is also about to be distorted by Xinyuan, the pace is getting faster and faster, and it pays more attention to time efficiency, and it also chooses to launch intensively for this important spacecraft.

Of course, the biggest reason is that there are many Xinyuan-2 rockets that can perform missions, and it is very simple to draw out two.

The Wentian and Mengtian experimental modules weigh about 43 tons each, and the Tiangong space station in the sky has been continuously increasing in quality because of the high-frequency supply launches over the past year.

After the launch of the two experimental modules, the Tiangong space station will surpass the Sheila space station by a single-digit advantage, and become the world's second largest man-made object in orbit with a mass of 230 tons.

The Sheila space station is third with a mass of 225 tons, while the Advance axial module with 220 tons is fourth.

It's a pity that the axial orbit of the Endeavour is higher, and it is not designed to dock with the space station, otherwise the combination will instantly surpass the ISS.

After the Aviation Development Commission issued a notice, Ma Yilong himself rarely appeared in the comments below, and then the Aviation Development Commission replied with a sentence inviting Ma Yilong to come to Qiongzhou to watch the rocket launch.

Ma Yilong's reply was: "There is a chance." ”

In a seemingly simple and ordinary online interaction, the two sides tacitly expressed their respective attitudes, as for Lao Ma himself?

When he sent the news, he had already decided to take a flight to Modu on the 17th and rush to Huaguo as soon as possible.

……

At the desert base, under the gaze of Yang Wei and the designers of a dry base, a gray plane looked different shades of color on the surface, like a J-20 with oxidized metal pushed out of the hangar.

The trailer towed the 2201 number 2201 on the side to the end of the runway, opened the cabin for the final inspection by the ground crew, and the pilot in the gray spacesuit sat not far away, waiting for him to come on the field.

Yang Wei looked at the strong sunlight above his head and gave a thumbs up to the base researcher next to him:

"Heat-insulating stealth paint can be done so quickly, cow."

"Not really, in fact, this has all the previous technical reserves, but it took some time to concoct."

It has been more than half a year since the desert base carried out the "Snow Bird" program, and now the original design of the body has finally been completed and is ready to enter the trial production research stage.

An important technology of the Snow Bird Project is thermal insulation/stealth coatings that can withstand ultra-high temperatures.

Although in fact, the temperature of the body can reach more than 1,600 degrees Celsius when the vehicle is violently rubbed against the atmosphere at 10 times the speed of sound, the rest of the body is also around 700 to 800 degrees Celsius.

At such a high temperature, infrared remote sensing satellites can still be found in theory, but satellites also have dead ends, don't they? It is not easy to detect without obtaining the exact flight path of the aircraft, so stealth is still the focus of consideration.

For example, the SR71 "Blackbird" reconnaissance aircraft, when flying at a speed of more than Mach 3.2, the maximum temperature of the fuselage is more than 450 degrees, and the average temperature is more than 260 degrees, but the radar reflection area is less than 1 square meter, which is a typical stealth aircraft.

The target set by the desert base for Xuehu is that the radar reflection area is less than 0.15 square meters.

The radar reflection area of the J-20 is less than 0.05 square meters, and the aerodynamic configuration and volume of the Snow Bird are there, and 0.15 square meters is about the same, and it is below 1 square meter, and there are still not many radars that can detect it.

Even if it is perceived that with the flight speed of the Snow Bird, a slight acceleration can get rid of the missile pursuit, and the current means except for laser weapons, no missile can pose an effective threat to the Snow Bird.

But the J-20 is different, after obtaining the XW-9, Yang Wei designed the J-20B interception model of the J-20.

Compared with the J-20, the J-20B has a longer fuselage, a smaller wingspan, an empty weight of 22 tons, and a maximum take-off mass of more than 44 tons, making it a typical heavy interceptor.

The J-20B sacrifices some maneuverability, but the two XW-9 on board can bring the maximum speed of sound after optimization 3.5 times the maximum speed of sound, and the maximum ceiling of 33500 meters, because of the fuel-saving characteristics of the XW-9 and the sacrifice of maneuverability in exchange for a smaller drag body, as well as the increase in internal fuel caused by the increase in body weight, the J-20B cruising radius has increased to 3000 kilometers, which is extremely exaggerated.

Such a J-20B needs to make a major change to the fuselage skin, and it is still necessary to ensure that the damage to the stealth is not too large, and the radar reflection area is still limited to less than 0.05 square meters.

For more than 8 months, through the cooperation of four research institutes, the skin problem of the J-20B was solved.

Unlike the SR71 more than 50 years ago, which needed to control the length of the skin stretch at high temperatures by reserving gaps, the J-20B uses expensive aerospace materials, and there will never be such a thing as oil leakage, and the weight basically remains the same, that is, the price has more than tripled.

The 611 Institute built a prototype verification aircraft of the J-20B by itself, and then quietly flew to the desert base, where it was coated with a special paint developed for the Snow Bird.

The Snow Bird needs to be repainted with stealth/heat insulation paint every time it flies, and for the J-20B, it can be flown four or five times and then replaced with a new one, during which the ground staff can check some weak points before each flight and repair them.

This paint formula was secretly carried out at the beginning of the aerospace fighter program in the last century, and a major breakthrough was made during the development of the "Shenlong", that is, about seven or eight years ago.

In Dou Ping's words, in the current world, this paint is the most advanced in the world, surpassing Aramco for a whole generation, so the degree of secrecy is extremely high, and the J-20B takes it for a test flight, which must be carried out in the desert base.

The new paint is a dirty metallic color after being brushed on the skin, and it is said that the price per kilogram is six figures, and the production is still very low, and the J-20B uses the production capacity that has been accumulated for 4 months.

Of course, this is also because the snow bird is still on paper, so the production is still in the laboratory.

When the official version of the J-20B is put into service, it is definitely not with this coating, but a downgraded version of the process that reduces costs and simplifies the process.

More than half an hour later, after the ground crew inspection was completed, the pilot in the spacesuit climbed into the cockpit and checked whether the ejection device was stuck by anything.

Due to the high temperature, the J-20B does not have a beautiful bubble cockpit, and the front half is composed of three thick flat glasses, which looks a bit like the cockpit of the eighth master.

And the cockpit looks a little like the two sides protruding, because the J-20B is an unprecedented long cruise interceptor, so the parallel two-seat layout is adopted to reduce the pilot's driving intensity, which is more comfortable than the tandem two-seater.

"01 (Dong Yu), are you ready?"

After a second or two, the test pilot pulled down the mechanical valve of the mask and fixed it, and then replied with the built-in microphone:

"01 is in good condition and ready to test fly!"

The heat generated by the high-speed flight of the J-20B is extremely high, in order to reduce weight, the volume of the cabin cooling equipment is limited, the air conditioning can not be turned on all the time, and only two pilots can be turned on for a while when they need to rest and change shifts.

Under normal conditions, the cabin temperature is as high as 39 degrees Celsius or more, and if you don't wear a simple spacesuit, you will be hot and dry.

Yang Wei: "I order, the high-altitude and high-speed flight test of No. 2201 will start immediately!" ”

The first flight of the J-20B has already been done in the 611 Institute, at that time, there was no stealth paint was yellow, and it was not conspicuous in a group of verification aircraft, but only subsonic test flights were done.

The test pilot was instructed to push the throttle to take off, and because the factor of the XW-9 engine and the aspect ratio of the fuselage were smaller, the taxiing distance was longer, and it took 400 meters to pull up.

The bad news: the tour is coming to an end

Good news: start going all out tomorrow

(End of chapter)