[Commentary] On April 16, the flight crew of Shenzhou 13 completed half a year of "space travel" and returned to Earth.
According to reports, the spacecraft adopted a rapid return scheme for the first time, and it only flew around the earth 5 times before landing.
[Explanation] How is the 5-lap quick return plan determined?
Recently, Shao Limin, deputy technical manager of the manned spacecraft system project of the Fifth Academy of Aerospace Science and Technology Group, answered in an interview with the media.
[Explanation] According to reports, it takes 1.5 hours for the spacecraft to circle the earth once. The Shenzhou 12 spacecraft will fly around the earth 18 times when it returns. This time, it will be compressed to 5 times to return, which greatly shortens the astronaut's "trip home" .
[Concurrent] Shao Limin, deputy technical manager of the manned spacecraft system project of the Fifth Academy of Aerospace Science and Technology Group
First of all, the choice of this lap is not as short as possible. As I mentioned earlier, if you choose short, it means that you will pass the landing field soon. If there is an abnormality after separation, you are There is no time to deal with it, you may have to wait longer on the track, so 5 laps is a compromise.
[Commentary] Shao Limin said that compared with the return process of the Shenzhou 12 spacecraft, the return procedure of the Shenzhou 13 spacecraft has not changed much except for the 5-lap quick return plan.
[Concurrent] Shao Limin, deputy technical manager of the manned spacecraft system project of the Fifth Academy of Aerospace Science and Technology Group
Compared with "Shen Twelve" (compared to), the main reason is that our flight control mode has been improved, but the specific return process has not changed. It will still involve the separation of the combination, the maintenance and measurement of the orbit before returning, and the following It is the separation of the orbital module and the return module, as well as the separation of the re-entry brake, the propulsion module and the return module, as well as the lift control of the re-entry of the return module. After entering the atmosphere, the parachute is opened at an altitude of 10 kilometers, and then the astronauts take the return. The cabin has landed softly, just such a process.
[Explanation] How to reduce the number of laps while completing the fixed operation?
Shao Limin said that by optimizing the return process, the ground researchers carried out the original serial work in parallel, thus shortening the waiting time of the astronauts in the return cabin of the Shenzhou spacecraft.
[Concurrent] Shao Limin, deputy technical manager of the manned spacecraft system project of the Fifth Academy of Aerospace Science and Technology Group
It actually has no adjustment to the software and hardware of our spacecraft. It is mainly because our flight control rhythm is more compact. For example, we changed the original serial to parallel, and we changed the tasks that needed to be done in two circles to one circle. This requires us to connect back and forth very nervously, so the five-lap rapid return this time puts a lot of pressure on the flight control personnel, but it does not have much impact on the spacecraft itself, because it does not involve soft hardware changes.
Reported by reporter Ma Shuisha and Liu Chao in Beijing
Responsible editor: [Ye Pan]