(Interview between the two sessions) Multi-type rockets jointly build a Chinese space station, Jiang Jie explains in detail the "Three Musketeers"

　　China News Service, Beijing, March 4th, title: Multi-type rockets jointly build a Chinese space station, Jiang Jie explains in detail the "Three Musketeers"

　　Author Guo Chaokai

　　China's space launches are expected to exceed 40 times in 2021, and the number and number of launches throughout the year will reach new highs.

The most notable of these is the space station construction task initiated by the joint efforts of multiple Long March rockets.

　　The Long March 5 B rocket will launch the core module of the space station, the Long March 2 F rocket will send astronauts into the space station by launching the Shenzhou manned spacecraft, and the Long March 7 rocket will launch the Tianzhou cargo spacecraft.

The reporter interviewed Jiang Jie, a member of the National Committee of the Chinese People's Political Consultative Conference, an academician of the Chinese Academy of Sciences, and a carrier rocket expert of the First Academy of China Aerospace Science and Technology Corporation, to explain in detail the "Rocket Three Musketeers" who jointly built the China Space Station.

Chang 5 B rocket will complete the first applied launch

　　The construction of the space station is a more complex and huge system, which includes multiple rendezvous and docking missions. This requires the rocket to complete a "zero window" launch, and requires the rocket to be ignited and launched in a pre-calculated time within minutes.

This is no small challenge for the new generation of carrier rockets Long March 5B and Long March 7.

　　According to the plan, the Long March 5B Yao-2 rocket will carry out the launch mission of the manned space station core module in the first half of this year. This is also the first application launch of the Long March 5B rocket.

This mission is the basis for carrying out the key technology verification phase of the manned space station, which directly affects the subsequent launch missions of cargo spacecraft and manned spacecraft. The whole country is concerned about it and should not be missed.

　　Jiang Jie said: "Long March 5B is a first- and a half-stage rocket. It is currently the only (type one) one-and-a-half-stage rocket in service in the world that has a simple system and high inherent reliability. It has overcome large thrusts during development. The technical problem of direct orbit precision control meets the high-precision orbital requirements of payload."

　　In addition, the Long March 5B rocket also uses the largest fairing in China, with a length of 20.5 meters and a diameter of 5.2 meters. During the development, it has broken through the separation control technology of the large fairing to meet the requirements of the space station's launch mission.

　Chang Er F rocket enters the high-density launch phase

　　This year, the Long March 2 F rocket will have 3 rockets coming into the field, 2 rockets will be launched, and 1 rocket will take turns on duty.

At the same time, in order to ensure the 100% safety of the astronauts, the Long March 2F rocket will also perform emergency duty to ensure that the emergency rescue mission of the space station can be performed in the first time in an emergency.

　　In order to adapt to and meet the needs of various missions and follow-up missions, the Long March II F rocket has continuously made adaptive improvements to improve the reliability of the entire rocket.

Compared with the Long March 2 F-Yao-11 rocket, of the 108 technical status changes of the Yao-Twelve rocket, 72 involve reliability improvement; of the 113 technical status changes of the Yao-13 rocket, 77 involve reliability improvement.

"The flight reliability of the Long March 2 F rocket has been increased from 0.97 to 0.98; at the same time, the escape system has been adaptively improved to further enhance the safety of the astronauts." Jiang Jie said.

　　Jiang Jie said that 2021 is the first year of the orbit construction mission of the manned space station, which is an important milestone for the Long March 2F rocket.

From 2021 to 2023, the Long March 2 F rocket is expected to complete 7 launch missions, and the responsibility is heavy. This also indicates that the Long March 2 F rocket has entered a high-density launch phase.

　　Changqi Rocket will launch Tianzhou cargo spacecraft with "narrow window"

　　According to the plan, the Long March 7 Yaosan rocket will launch the Tianzhou-2 cargo spacecraft to achieve rendezvous and docking with the core cabin in orbit.

Due to the particularity of manned space missions, the rockets that perform the mission will use the "zero window" launch technology.

The new-generation launch vehicle uses low-temperature fuel, and the pre-launch process is complicated. Especially after the 3-minute process, there are many system items such as power, control, and ground launch support, and the coupling is serious. Any problem in any link will cause the launch window to be missed.

　　Jiang Jie revealed that in the space station mission, the Long March 7 rocket used the new method of satellite navigation timing to automatically correct the take-off time, expanding the launch requirement of the "zero window" of the manned space rendezvous and docking mission to a "narrow window" to ensure orbit with the target. The accuracy of the surface into orbit improves the adaptability of rocket launch missions in the space station project.

　　In the Tianzhou-2 cargo spacecraft mission, the Long March-7 Yao-2 rocket will carry out technical improvements in terms of simplifying telemetry parameters and improving the coating of the transition section.

In order to further improve the reliability of the rocket system and products, and to draw inferences about other rocket quality problems, the Long March 7 Yaosan rocket will also improve the design of the rocket and ground products.

　　According to the manned space station construction mission plan, China will continue to implement 11 missions this year and next, and complete the space station orbit construction around 2022.

"The space station construction mission has attracted worldwide attention. Multiple Long March rockets will perform the same mission. This is the first time in the history of China's aerospace." Jiang Jie said.

(Finish)