What was China's space achievement in sending a man into space for the first time?

Shenzhou 5 manned spacecraft is the first manned spacecraft in China based on unmanned spacecraft, which can carry an astronaut and run in orbit for one day. During the whole flight, we will provide the astronauts with necessary living and working conditions, and at the same time send the astronauts' physiological data and TV images to the ground to ensure the astronauts' safe return. The spacecraft consists of orbital module, return module, propulsion module and additional section. The manual control function of the spacecraft and the subsystem of environmental control and life support provide a guarantee for the safety of astronauts. The spacecraft was launched by the "Long March II F" carrier rocket to an initial orbit with perigee of 2 km, apogee of 35 km and inclination of 42.4. After orbit change, it entered a circular orbit of 343km. The spacecraft circled the earth 14 times and landed in a predetermined area. Hero astronaut Yang Liwei carried out this manned space mission.

I. Brief introduction of mission implementation

The manned space mission in Shenzhou 5 is mainly to comprehensively assess the manned environment, obtain relevant data on astronauts' living environment and safety, and comprehensively assess the working performance, reliability, safety and coordination among systems of the project. The spaceship took an astronaut, flew for about one day, and returned on the 14th lap around the earth. Astronauts can manually reissue important instructions such as separation of ship and arrow and deployment of windsurfing according to pre-specified procedures and ground instructions. The spacecraft has the ability of autonomous emergency return, manual control return and return on the second and third days.

according to the plan, China's first manned flight was carried out from October 15th to 16th, 23. Manned spacecraft and launch vehicles enter the launch area to add propellant after completing assembly and testing in the technical area of the launch site. Sixteen hours before the launch, Yang Liwei, the first astronaut, was selected from the first flight echelon of three astronauts. The astronaut entered the spacecraft about 2 hours and 45 minutes before the launch.

At 9: Beijing time on October 15th, 23, the first-stage rocket engine and four booster engines were ignited at the same time. The rocket flew for 12 seconds to separate the escape tower, 137 seconds to separate the booster, 159 seconds to separate the first and second stages of the rocket, 2 seconds to separate the fairing, 46 seconds to shut down the second main engine, and 587 seconds to separate the ship and arrow. The spacecraft entered an elliptical orbit with an inclination of 42.4 degrees, a perigee altitude of 199.14 kilometers and an apogee altitude of 347.8 kilometers. After entering the orbit, the spacecraft established its orbit attitude, unfolded the solar array on the propulsion module, oriented the sun, and changed its orbit on the fifth lap to enter a 343-kilometer circular orbit. During the flight, the ground keeps close contact with the astronauts, and understands the physical state of the astronauts through physiological telemetry parameters; Astronauts monitor the execution of important instructions during the flight and the running state of the spacecraft.

Shenzhou 5's manned spacecraft returned to Earth after 14 autonomous orbits. In the first lap of return, the precise parameters of return braking are injected into the spacecraft by the ground monitoring station. The spacecraft yawed 9 degrees, and the orbital module was separated from the spacecraft. Then yaw for 9 degrees and brake to enter the return orbit. When the altitude drops to 145 kilometers, the propulsion module is separated from the return module. The return capsule re-entered the atmosphere, crossed the "black barrier" and then flew over the main landing site. The parachute was opened to slow down according to the procedure, and when it descended to the ground about 1 meter, the landing buffer engine was ignited. The return capsule landed safely at 6: 23 am on October 16, and astronaut Yang Liwei returned smoothly after flying for 21 hours and 23 minutes. After that, the orbital module continued to fly in orbit for about half a year to carry out relevant space science experiments and technical experiments.

II. Technical Achievements of Shenzhou 5 Manned Mission

An astronaut is the commander and pilot of this mission. During the flight, the astronauts will not enter the orbital module and take off their spacesuits, and manually reissue the instructions such as separation of ship and arrow, sail deployment and push-back separation according to the pre-specified procedures and ground command, so as to complete the work of spacecraft state monitoring, blood pressure measurement, photography, eating and sleeping. The normal flight time of the autonomous flight segment is one day. After the spacecraft enters orbit, it changes orbit on the fifth lap and returns to the main landing site after braking on the 14th lap. Have the ability to return on the second day and the third day. The spacecraft orbital module stayed in orbit for half a year, and the main load was CCD camera. The organization and implementation shall be carried out in accordance with the principle of daytime emission and daytime recovery.

The spacecraft has the capability of autonomous emergency return, which allows astronauts to return to 1 emergency landing zones scheduled around the world in case of emergency; With manual control return function, astronauts can manually control the return to the ground when the automatic return system fails.

The selection and training of astronauts have completed the study and training of basic theory and professional technology, flight procedures and mission simulation, space environment adaptability, lifesaving and survival. Man-ship joint test project; Spacecraft training simulator and manual training simulator training. At the end of June, according to the assessment, six preparatory astronauts were selected for intensive training, and after the intensive training was completed in September, the first manned flight of three astronauts was determined.

According to the previous four flight tests, the launching site, TT&C communication and landing site system further improved the technical status, implemented the mission implementation plan, and re-inspected, calibrated and maintained the equipment as planned, and conducted drills and joint debugging. The scheme of medical supervision, medical insurance and medical rescue for astronauts has been determined. The preparations for these systems were completed at the end of September to ensure the implementation of the task in October.

in order to ensure the complete success of the first manned mission, in 23, the overall project arranged a large number of reliability and safety verification tests, such as the engine reliability test of spacecraft and rockets, the ignition tests of various pyrotechnic mechanisms and devices of spacecraft, the life and reliability tests of various moving parts, the reliability growth test and comprehensive stress test of electronic equipment, and the verification tests of fire prevention, moisture prevention and dew prevention measures of spacecraft. Aiming at the manual function that can't be assessed in unmanned flight test, a large number of ground simulations and tests are arranged, such as rocket escape simulation, spacecraft emergency rescue and autonomous emergency return simulation in orbit, manual control function simulation, system-level fault simulation and countermeasure verification simulation, etc., and special attention is paid to the elimination and protection of harmful gases in the spacecraft cabin, impulse noise, seat lifting and cushioning performance test and landing impact test related to astronaut safety.

from 1999 to 23, China successfully launched four unmanned spacecraft and one manned spacecraft, which broke through 13 key technologies such as lift control for manned spacecraft reentry, emergency rescue, soft landing, GNC fault diagnosis, cabin separation and heat protection. As a cross-century project in China's high-tech field, shenzhou spaceship's overall performance is superior, reaching the international advanced level in 199s. The structure and overall mode of "Three Cabins and One Section" in shenzhou spaceship have distinct China characteristics. shenzhou spaceship has a high starting point and a high degree of intelligence. Although China's manned spaceflight project started late, it didn't start from the spacecraft in the Gagarin era: first unmanned spacecraft, then single-person spacecraft, and finally multi-person spacecraft, but stepped through the 4-year development process of the United States and the Soviet Union and achieved leap-forward development. Foreign manned spacecraft began to test the astronaut's environmental control and life support system from carrying small animals, while China adopted an advanced modern device-simulated dummy to simulate the oxygen and carbon dioxide consumed by the "astronaut" and tested the physiological signal changes of the "astronaut" through the advanced ground medical monitoring platform.

In addition, the take-off mass and the maximum cockpit diameter of shenzhou spaceship in China are far greater than those of Mercury in the United States and Dongfang in the Soviet Union. The configuration of shenzhou spaceship has more functions than that of Mercury and Dongfang, and it is more complicated in the connection and separation technology of electric, gas and liquid circuits between cabins. In terms of power supply, shenzhou spaceship has adopted a power supply scheme based on solar array, which has made great progress compared with the power supply systems of Mercury and Dongfang. Especially in shenzhou spaceship, the lift-type reentry is adopted, and the GNC subsystem is used to control the lift in the reentry process. This is a more advanced return method than ballistic reentry, which can greatly improve the accuracy of the spacecraft returning to the landing site, reduce the peak value of reentry overload, and alleviate the pain of astronauts when returning to the ground. Compared with foreign advanced manned spacecraft in 199s, shenzhou spaceship is roughly equivalent to Soyuz TM spacecraft in terms of reentry mode, landing accuracy and reentry overload peak value, and has created a more comfortable environment for astronauts' work and life. Shenzhou is an excellent tool for China's transportation between heaven and earth, and it can be called the real Shenzhou for ferrying the Tianhe River.

Third, the technical level of manned launch vehicle

In terms of manned launch vehicle technology, the "Long March II F" manned rocket accurately sent shenzhou spaceship into the vast space five times. The reliability of "Long March II F" rocket has been improved to .97, which makes the safety of astronauts reach .997 and the success rate is 1%. The reliability, safety and success rate of "Long March II F" rocket have reached the international advanced level. All kinds of products of manned rockets have reached the expected goals in terms of design, quality, function and flight results. The overall performance of China's Long March II F rocket is excellent, indicating that China's space launch vehicle has entered a mature stage. This launch is the 71st flight of the Long March rocket, and it is also the 29 consecutive successful flights of the Long March rocket since October 1996. The launch success rate of the Long March rocket reached 91%.

"Long March II F" rocket is a brand-new launch vehicle used for manned space flight for the first time in China's space history, and it is also the rocket with the largest take-off mass, the longest length and the most complicated system among all launch vehicles in China at present. The "Long March II F" rocket has adopted 55 new technologies for the first time in domestic rockets, among which the main key technologies such as rocket fault detection system and escape system are worldwide problems. Hundreds of rocket failure modes and escape criteria have realized the automatic detection and diagnosis of the failure of the launch vehicle in the waiting phase and the ascending phase, and can send fault information to the escape system to implement the automatic escape of astronauts and the command escape on the ground. This technology has reached the international advanced level.

In order to improve the reliability and safety of the rocket, the important systems and key parts of the Long March II F rocket adopt redundancy technology for the first time, which gives the rocket "double insurance". In case the main system fails, it can be quickly switched to the backup system to ensure the normal work of the rocket and the safety of the astronauts.

The "Long March II F" rocket has achieved "three sags" in the domestic space history: the spacecraft and rocket have achieved vertical assembly test in the technical area; Under the condition that the launch vehicle is vertically erected, driven by the spontaneous power supply, it can walk 1.5 kilometers along the rail. It has achieved a long-distance launch of 1.5 kilometers. These technologies have reached the international advanced level.

The escape tower placed at the top of the "Long March II F" rocket is about 8 meters long and looks like a huge lightning rod. The rocket's low-altitude escape is realized through the escape tower. Low-altitude escape refers to the escape from the launch pad 3 minutes before takeoff to 2 minutes after takeoff, that is, before the rocket is thrown into the escape tower. The "Long March II F" rocket used in China's first manned launch has three modes to ensure that astronauts can escape safely in case of accidents. These three modes are: low-altitude escape, high-altitude escape and emergency separation of ship and arrow.