China Launches Experimental Refueling Satellite! [Long March 3B/E Y104]
China has launched an experimental refueling satellite for its first launch of 2025.
China’s first launch of 2025 blasted off from Launch Complex 3 at the Xichang Satellite Launch Center at 04:00 am China Standard Time (January 7th), or 22:00 pm Universal Coordinated Time (January 6th), with a Long March 3B/E sending a single satellite to geostationary transfer orbit.
Aboard the first Long March 3B/E this year was the Shijian-25 (实践二十五号) satellite, developed by the Shanghai Academy of Spaceflight Technology. Shijian-25 is stated as being a technological demonstration mission for refueling other spacecraft along with extending their operational lives.
China already routinely refuels its Tiangong Space Station in low Earth orbit via the Tianzhou cargo spacecraft, having done so since a successful test in 2017 with Tiangong-2. However, a satellite refueling test mission beyond low Earth orbit is not believed to have occurred yet.
A refueling spacecraft was announced back at the Zhuhai Airshow in 2021 with details stating (shared by Chinese space enthusiast Vony7):
“The refueling spacecraft can carry 1.3 tons of fuel at one time, accounting for 52% of its own weight. It can be called a "space mobile tanker". For a satellite that is "in urgent need of rescue", it only needs to add 50 kilograms of fuel, and the satellite can extend its life by about one year. Compared with the cost of re-launching a geostationary orbit satellite, the cost is reduced by 35%. Therefore, the realization of on-orbit fuel refueling technology is tantamount to timely assistance for expensive satellites.”
“After receiving the help signal from the satellite with fuel shortage, the vehicle will be guided by the ground dispatch system to the rear of the satellite, and use the navigation system to track and approach the satellite autonomously. When it arrives within about 2 meters of the satellite, with the cooperation of the robotic arm, it will achieve a close connection with the satellite refueling port and deliver fuel to the satellite.”
If there are any problems with this translation please reach out and correct me.
With Shijian-25, China is likely to be building on previous experience obtained during the Shijian-21 mission, launched back in October 2021. While not a refueling test it was a notable test due to it servicing and moving a satellite in geostationary orbit sometime between October 2021 and January 2022. Combining the capabilities of the two missions could allow China to perform possibly world-leading spacecraft life extension missions (Paid article linked).
Shijian-designated spacecraft are flown to figure out best operational practices, with the name literally translating to Practice in English. Shiyan (实验) is a similar satellite designation used for technology development spacecraft, and the name literally translates to Experiment.
According to the China Aerospace Science and Technology Corporation and repeated by the China Academy of Launch Vehicle Technology, the Long March 3B/E launch vehicle is expected to perform over ten missions in 2025. This is a small increase over last year’s eight launches. An increased cadence is possible due to continuous optimizations to vehicle production, testing, launch preparations, and team training. The China Academy of Launch Vehicle Technology also stated that the Long March 3B/E is planned to be launched over a dozen times per year, with as little as fifteen days between missions, following its last mission of 2024.
Today’s mission was the 102nd launch of a Long March 3B vehicle, and the 555th launch of the Long March launch vehicle series. Along with these, this was the 1st launch from China in 2025.
Liftoff video via Our Space on WeChat/Weixin
As of updating (January 23rd), the Y number for this launch is believed to be Y104, this article will be updated if clarified otherwise.
Chinese companies, state-owned and private, use Y followed by a number to serialize launch mission numbering, similar to NASA with STS.
Check out the previous Long March 3B/E launch
What is the Long March 3B/E?
This section is for those less familiar with China's Long March series of launch vehicles.
The Long March 3B is an older-generation geostationary orbit workhorse of the China Academy of Launch Vehicle Technology. The first two stages and four boosters of the rocket burn Dinitrogen Tetroxide and Unsymmetrical Dimethylhydrazine, with liquid hydrogen and liquid oxygen in the third-stage.
Over the rocket's almost twenty-eight-year launch history, two versions of the vehicle have flown, the 3B and 3B/E. Since 2012 only the 3B/E variant has flown due to its increased payload capacity. The payload capacity of the launch vehicle is currently as follows:
11,500 kilograms to low Earth orbit
7,100 kilograms to a sun-synchronous orbit
5,500 kilograms into a geostationary transfer orbit
2,000 kilograms into geostationary orbit
The first-stage is powered by four YF-21C engines that burn Dinitrogen Tetroxide and Unsymmetrical Dimethylhydrazine to generate 302 tons of thurst, while the boosters are powered by one YF-25 engine burning the same fuel to generate 72 tons of thrust each. Combined the four boosters and first stage generate a thrust of 590 tons. The second stage is powered by one YF-22E and four YF-23F vernier engines that also burn Dinitrogen Tetroxide and Unsymmetrical Dimethylhydrazine to generate 81 tons of thrust. The third-stage is powered by two YF-75 engines that burn liquid hydrogen and liquid oxygen to generate 17 tons of thrust.
On the launch pad, the Long March 3B/E is 56.3 meters tall and weighs 458,970 kilograms when fully fuelled. The first and second-stage have a diameter of 3.35 meters, while the third-stage has a diameter of 3 meters, along with the four boosters diameter of 2.25 meters, and the fairing has a diameter of 4.2 meters.
So far every Long March 3B launch has occurred from the Xichang Satellite Launch Center, in the south of Sichuan province.