China resumed construction of its Space Station in 2022, launched TianZhou-4 Cargo Spacecraft

Lifted off from Wenchang spaceport, TianZhou's autonomous rapid flight profile completes Rendezvous and Docking to the Country's Space Station in 6 hours and 58 minutes.

Long March 7 Y5 carrier rocket lifted off with Tianzhou-4 cargo Spacecraft, at the Wenchang Spaceport in Hainan Island. credit: CASC

May 10, 2022 China launched the Tianzhou-4 (天舟四号, Tiān Zhōu Sì Hào, TZ-4) cargo spacecraft on Monday, May 9, 2022, with liftoff at 01:56:29,373 Beijing time(May 10) – 17:56:29.373 UTC. The Long March-7 No. Y5 rocket carrying the spacecraft took off from the Wenchang Spaceport off the coast of the island province of Hainan in southern China. The spacecraft was placed in an initial 200 km × 400 km orbit, with an inclination of 41.46°, to then use its engines to meet and dock with the station.

Tianzhou-4 Cargo Spacecraft Docked with Tianhe core module in Low Earth Orbit. Credit: BACC

According to the plan, The spacecraft docked with the aft (rear) port of the station's Tianhe core module, Today at 0054 UTC (08:54 Beijing). Delivered supplies, equipment, and propellant, which will be used by its third visiting crew, to be launched from the Shenzhou-14 spacecraft, planned NET June 5.

Infographics by S.I and HDE

The Tianzhou-4 mission is the third unmanned flight to transport cargo to the Chinese orbital station's Tianhe module. "China plans to transform the space station into a world-class space laboratory that will allow long-stay astronauts and large-scale scientific, technological and application experiments," said Zhou Jianping, chief designer of the country's manned space program. This is the 22nd launch mission of the country's manned space project. It is the first launch mission of the space station construction from the key technology verification stage to the on-orbit construction stage. It is also the 420th flight of the Long March series of launch vehicles.

The Spacecraft Measuring 10.6 meters in length and with a maximum diameter of 3.35 meters, the Tianzhou-4 had a maximum take-off weight of 13.5 tons and carries 6.8 tons of goods and materials. The payload-to-weight ratio combined with the 6.5-ton payload capacity is 0.48.

The items packed on board are divided into five main types:

• Supplies for the expedition of the Shenzhou-14 mission.

• Toolkits for space station maintenance

• Equipment and cartridges/containers for scientific research

• Refrigerator to store biomedical research results

• Seeds for cultivation on board.

Loading of Supplies and Cargo to Tianzhou-4 spacecraft, Courtesy: CCTV

Tianzhou-4 in orbital flight configuration – The spacecraft adopts the structure of two modules, a cargo compartment, and a propulsion compartment. The cargo compartment is a sealed compartment with a maximum diameter of 3.35 meters. It is divided into three parts: a front cone section, a cylindrical section and a truncated cone-shaped rear section. The cargo is stored in the cylindrical compartment, and the diameter of the propulsion compartment is about 2.5 meters. Tianzhou is equipped with 36 orbit and attitude control engines, four of which are 490 Newton thrust orbit control engines and the others are 32 attitude control engines with thrusts of 150N, 120N and 25N respectively. After docking with the space station, the spacecraft may also capable of orbital raising of station, apart from the station keeping "Hall effect" thrusters of the core module.

Tianzhou-4 Cargo Spacecraft (CMSA)

The spacecraft has 400-liter metal diaphragm propellant tanks. They are divided into propulsion tanks and supplementary tanks. The two types can be interconnected to give flexibility to station refueling tasks or self-propelled. The main propellant capacity is 3.1 tons, and the supplementary propellant capacity is 2.1 tons.