China Express has added a new delivery address - space! What is so special about the Tianzhou spacecraft?

Tianzhou spacecraft publicly "collects items"!

Two ships per year are planned to be normalized

Recently, the China Manned Space Engineering Office officially issued the "Announcement on Soliciting Opportunities for Scientific and Technological Experiments and Application Projects on the Tianzhou Series of Cargo Spacecraft", publicly soliciting projects for onboard transportation.

Related announcement content source: China Manned Space Engineering Official Website

This public solicitation marks the first time in the history of China's manned space program that cargo spacecraft resources have been opened to the public.

▲ Schematic diagram of the Tianzhou cargo spacecraft (provided by the Fifth Academy of Aerospace Science and Technology)

"Tianzhou Ferry Ticket" detailed description:

"Ride" object

This solicitation activity is mainly aimed at government agencies, research institutes, educational institutions, enterprises, industry organizations and other units, and is soliciting scientific and technological test and application projects based on the Tianzhou series cargo spacecraft platform.

“Freight” scope

1. The projects carried on board should be oriented towards the forefront of science and technology and conform to the needs of the national development strategy and the development trend of science and technology.

(II) The projects should be forward-looking and innovative, or have application value for industrial development.

(III) The necessity of carrying out experiments in space must be fully demonstrated and must be engineering feasible.

▲ Tianzhou-3 launch (data map)

Frequency of “shipping”

At present, the in-orbit construction of China's space station is progressing smoothly as planned. After completion, it will enter the application and development stage. The Tianzhou series of cargo spacecraft will be launched at an average frequency of two ships per year.

This series of cargo spacecraft is independently developed by China. It consists of a cargo cabin (generally fully sealed) and a resource cabin. The orbit is no higher than 450 kilometers. The material uplink capacity is about 6.5 tons and the flight time in orbit is about 1 year. Because of its outstanding advantages such as strong transportation capacity, long flight time and high emission frequency, it is not only a dedicated cargo and supply transportation platform for China's space station, but also can be expanded into a space science and technology and application project test (experimental) platform open to the society.

▲ Schematic diagram of the Tianzhou cargo spacecraft (provided by the Fifth Academy of Aerospace Science and Technology)

This public solicitation is the first time in the history of China's manned space program that cargo spacecraft resources have been opened to the public. The purpose is to further leverage the comprehensive benefits of the manned space program and promote innovative research in space technology and the cultivation of high-tech aerospace talents.

In the future, China's manned space program will be open to the whole society and international partners in a planned, targeted and organized manner, striving to achieve co-construction, sharing and common use, and make positive contributions to benefiting all mankind and building a community with a shared future for mankind.

As soon as the news came out, it attracted great attention. After all, this is the first time in the history of manned space flight that cargo spacecraft resources are open to the public. It is reported that the Tianzhou series of cargo spacecraft will be launched at an average frequency of 2 per year, which means that China Express has added a new delivery address - space.

As the chosen "courier", what exactly is the "extraordinary feature" of the Tianzhou cargo spacecraft? Let's explore it together.

Space Supply:

Take on multiple "express delivery" tasks

The Tianzhou cargo spacecraft is an important part of the manned space program. Its main mission is to provide various supplies for the Chinese space station. So far, it has undertaken three missions.

As early as 2017, the Tianzhou-1 spacecraft delivered cargo to the Tiangong-2 and carried out a number of tests including the verification of rendezvous and docking technology; just this year, after the Chinese space station was in orbit, Tianzhou-2 and Tianzhou-3 were launched in succession to dock with the core module, delivering a number of supplies including extravehicular spacesuits to the astronauts in the space station.

Tianzhou-1 docks with Tiangong-2

Image source: CCTV News

On October 17, CCTV live broadcast the astronauts unpacking packages, which caused a great response on the Internet. The "courier" who delivered the package was Tianzhou-3.

Astronauts are unpacking a package. Source: CCTV News

After reading these rich experiences, you should not doubt the capability of the Tianzhou spacecraft. Thanks to this capability, the Tianzhou spacecraft also undertakes the tasks of supplying propellant to the space station and serving as a space science and technology test platform.

Two-cabin structure:

Being able to pretend is the hard truth

How does the Tianzhou cargo spacecraft manage to shoulder so many responsibilities?

It turns out that Tianzhou is a real giant. It is over 9 meters long, with a maximum diameter of 3.35 meters, a total weight of 13 tons, a maximum cargo capacity of over 6 tons, and can fly independently in space for 3 months. Many of its technical indicators have reached the international advanced level.

In order to improve the cargo carrying capacity, the Tianzhou spacecraft has also optimized its internal space. Take Tianzhou-2 as an example. It adopts a two-cabin structure design. The cargo cabin is designed as a fully enclosed cabin, which fixes 160 packages in each cargo compartment like a honeycomb; the other cabin is the propulsion cabin, which carries 2.5 tons of propellant to provide power for itself and the space station.

Tianzhou-2 Image source: CCTV News

It is not difficult to see that the Tianzhou spacecraft is packed full every time, so it is not easy to send it into space. Therefore, if it wants to perform well, it cannot do without its best partner - the Long March 7 carrier rocket.

Long March 7 carrier rocket Source: China Aerospace Science and Technology Corporation

"Best Partner":

Long March 7 carrier rocket

Long March 7 is a "full-time driver" for launching cargo spacecraft, and is also a new generation of medium-sized carrier rocket newly developed by my country. It comprehensively utilizes the mature technology of Long March 2 and the new technology of Long March 5, and has stronger environmental adaptability and reliability. The YF-100 liquid oxygen-kerosene engine used in the core stage and booster stage is the same as that of Long March 5, which not only has stronger safety, but also greatly improves the carrying capacity.

Of course, for a good courier, delivery speed is also an important KPI (key performance indicator). So how does the Tianzhou spacecraft, as a "space courier", perform in this regard?

You should know that the Tianzhou cargo spacecraft uses rapid autonomous docking technology. The use of this technology shortens the time from launch to docking to 8 hours. Compared with the "Four Links and One Delivery", it is definitely a crushing level.

The so-called rapid autonomous docking means that the spacecraft uses Beidou's navigation information to achieve long-distance, fully autonomous navigation calculation and guidance control without human assistance, thereby achieving rendezvous and docking with the space station. The spacecraft relies on autonomous flight throughout the process and does not require ground participation, which greatly shortens the docking time and significantly improves delivery efficiency.

Tianzhou-2 rendezvouses and docks with Tianhe core module Source: Global Times

Science and technology are the biggest driving force. It is the continuous technological innovation that enables China's aerospace industry to continue to develop. The Tianzhou cargo spacecraft is an important achievement brought about by a number of cutting-edge technological advances. At the same time, as an important verification platform for future space experiments, Tianzhou will also feed back to the development of science and technology and promote the continuous advancement of my country's strategy of becoming a space power.

Comprehensive sources:

China's manned space program official website, China Aerospace Science and Technology Corporation, Shanghai Science and Technology Museum, CCTV Military, etc.