In-orbit propellant replenishment

It takes about 5 days for the propellant to be replenished in orbit. The design of cargo spacecraft is to complete docking in 3 to 5 days, because no one needs to worry, and a few more laps can save fuel needed for attitude adjustment. The more fuel is saved, the more fuel can be used for replenishment.

In the past, the docking between unmanned and manned spacecraft was mainly circuit connection. In order to replenish fuel, the cargo spacecraft added a liquid connection with Tiangong-2, with different interfaces for propellant and oxidant. There are 29 steps to refuel, and the process is very complicated. In case of emergency, it needs to be handled in orbit, which requires the complex operation of the ground flight control system.

This time, the key steps such as pipeline leak detection, gas recovery of Tiangong No.2 tank, propellant transportation and propellant blowing were carried out successively. Under the precise control of the ground operator, the whole on-orbit refueling process is completed by Tianzhou No.1 and Tiangong No.2, in which Tianzhou No.1 is responsible for tank pressurization, pipeline leak detection and propellant delivery to Tiangong No.2; Tiangong-2 is responsible for recovering the gas in the tank and receiving the propellant from the cargo ship.

Rapid rendezvous and docking

Tianzhou-1 will carry out a rapid rendezvous and docking test, which takes only 4 to 6 laps to complete. When this technology is mature, it can be used to dock manned spacecraft.

scientific experiment

Tianzhou-1 is equipped with more than 10 application loads and 40 devices, and will carry out 13 space experiments. The equipment can be installed inside the warehouse or hung outside the hull, which not only improves the space utilization rate, but also meets the needs of different tests to the greatest extent.