The cargo ship is 10.6 meters long and has a maximum diameter of 3.35 meters. Its maximum takeoff weight is 13.5 tonnes, enabling it to carry over 6 tonnes of supplies. Tianzhou-1 will dock with Tiangong-2 space station three times. After the first docking, aerospace engineers will test the controlling ability of the cargo spacecraft over the two spacecraft. The second docking will be conducted from a different direction, which aims to test the ability of the cargo ship to dock with the space station from different directions. In the last docking, Tianzhou-1 will use fast-docking technology. Previously, it took China about two days to dock, while fast docking will take about six hours. Refueling is conducted during docking.
CAS news release, April 21, 2017