China News Service, Beijing, May 5 (Guo Chaokai, Jiang Zhe) At 18:00 on May 5, the Long March 5B carrier rocket was ignited at the Wenchang space launch site in China, successfully launching a new generation of manned spaceship test ship and flexible inflatable The cargo returned to the test cabin and sent to the scheduled orbit, the first flight mission was a complete success.

　　The Long March 5B carrier rocket was developed by the China Academy of Launch Vehicle Technology, a subsidiary of China Aerospace Science and Technology Corporation. It is China ’s first new-generation large-scale liquid carrier rocket using a first- and a half-configuration. .

　　In order to serve as an "exclusive train" for transporting the cabin section of the space station, the Long March 5B carrier rocket has carried out a number of technical breakthroughs and innovations, and has mastered a number of core technologies with independent intellectual property rights. The reporter interviewed relevant experts to decode the four "black technologies" of the Long March 5B rocket:

　　——One of "Black Technology": Development of Super Large Fairing

　　The fairing of the Changzheng No. 5 B rocket has a diameter of 5.2 meters and a length of 20.5 meters, which is equivalent to the height of a six-story building. It is currently the largest fairing in China and is specially tailored for the loading of the space station.

　　In order to improve the aerodynamic characteristics, the rocket fairing adopts a streamlined von Carmen curve shape, which can better reduce the air resistance and reduce the impact of the load. At the same time, the separation of the fairing adopts a rotary separation scheme to ensure that the oversized fairing can be separated safely and reliably.

　　—— "Black Technology" Part Two: "Zero Window" Launch

　　In order to meet the requirements of the space station rendezvous and docking, the Long March 5B rocket needs to achieve a "zero window" launch and control the launch time error within 1 second. As China's first low-temperature rocket to launch a "zero window", the Long March 5B rocket needs to weigh the relationship between the "advance" and the "consumption" of the "evaporation" of the low-temperature propellant.

　　Li Dong, chief designer of the Long March 5B carrier rocket, said that the development team has achieved reliability improvement of key systems through reliability analysis and testing; through pre-launch process optimization, the adaptability of each system to "zero window" launch has been improved .

　　—— "Black Technology" Part III: Separation of large-diameter cabin arrows

　　The connection interface between the space station cabin section and the Long March 5B rocket is more than 4 meters in diameter. The separation of cabin arrows needs to consider various factors such as reliability and impact environment. It is necessary to ensure safe separation and try to minimize the impact environment that occurs during the separation process. The adverse effects are minimized.

　　To this end, the development team adopted the "impact-isolated frame + damping box" impact reduction scheme, and applied the "particle damping technology" to achieve the effect of vibration and noise reduction. After test verification, the separation of the separation interface of the cabin arrow has been effectively improved.

　　—— “Black Technology” No. 4: Direct thrust into orbit

　　As a first-stage and half-configuration rocket, the Long March 5B rocket does not have a separate attitude adjustment and final speed correction system, but uses the first-stage rocket to directly send the payload into a predetermined orbit. When the first-level engine is turned off, the thrust of about 140 tons disappears within a few seconds, which is equivalent to the sudden "braking" of a high-speed train, and it must be steadily stopped at the designated position.

　　Li Dong said that in order to meet the higher requirements of orbital accuracy, separation safety and other aspects, the research team carried out technical research in orbital attitude control, orbital accuracy control, and separation safety control. By adopting attitude control gain optimization and compound guidance methods, the rocket's attitude control accuracy is improved, and the effect of guidance errors on accuracy is reduced, so that the rocket is in the best "attitude" and most accurate position when separating. At the same time, two off-orbit rockets were added, so that the rocket's first-grade arrow body can avoid the orbital surface of the space station cabin section in time, and the safety margin for the separation of the cabin arrow was improved.

　　It is worth mentioning that the Long March 5B launch vehicle and the Long March 5 launch vehicle belong to the “family” of the Long March 5 series rockets, and are currently the largest rocket series in China. Although the appearance is somewhat similar, there are many differences in the design and use of the two rockets.

　　From the configuration point of view, the Long March V launch vehicle uses a two-stage half configuration, and the Long March V B launch vehicle uses a first-order half configuration. From the appearance point of view, the super-large fairing of the Long March No. 5 B rocket is its most prominent feature. It is nearly 8 meters longer than the Long March No. 5 fairing, making it the largest rocket fairing in China. In terms of use, the Long March V launch vehicle is mainly used to launch large satellites with high orbits and various deep space probes, such as Chang'e V lunar probe, Mars probe, etc .; the Long March V B launch vehicle is mainly used to launch Large satellites and spacecraft in low-Earth orbit, such as the core module and experimental module of the manned space station. In terms of carrying capacity, the Long March V rocket's geosynchronous transfer orbit (GT0) carrying capacity is about 14 tons, and the Long March V rocket B's low earth orbit (LEO) carrying capacity is not less than 22 tons.

　　According to Wang Jue, chief commander of the Long March 5B carrier rocket, the Long March 5B rocket has experienced nearly ten years of development from project establishment to first flight. "As a new type of launch vehicle specially developed for the construction of a manned spaceflight engineering space station, the successful first flight of the Long March 5B rocket marked that the space station project construction has entered a substantial stage." Wang Jue said. (Finish)