At morning 23rd April 2025 Beijing time CNSA –China National Space Administration, the Long March 5B Yao-7 carrier rocket from the Wenchang Space Launch Site in Hainan Province, China, People’s Republic of China., On the morning the “Long March 5B” Yao-7 carrier rocket and satellite assembly were vertically transferred from the vertical assembly and test plant to the launch tower on a mobile launch platform, and the launch mission preparations entered the final stage
On the morning of April 23, 2025 Beijing time (hereinafter referred to as Beijing time), at the Wenchang Space Launch Center on the northeast coast of Hainan Island, the “Long March 5B” Yao 7 carrier rocket satellite-rocket combination was transferred from the vertical assembly and test plant to the launch position, and the “Long March 5B” sixth launch mission entered the refueling and launch phase.
The most powerful Long March rocket near the Earth once again carries out a giant constellation network launch!
At 04:10 Beijing time on April 29, 2025, the Long March 5B Yao-7 carrier rocket/Yuan Zheng-2 upper stage ignited and took off from the 101 work site of the Wenchang Launch Center. Subsequently, the carrier rocket stage and upper stage relayed the delivery of 10 satellites of the satellite Internet low-orbit 03 group directly into polar orbit (PO).
The satellite internet low-orbit satellite group 03 is the China Star Network low-orbit satellite group 03, which belongs to the low-orbit satellite part of China Star Network and is developed by the Communication and Navigation Satellite General Department of the Fifth Academy of China Aerospace Science and Technology Corporation. The satellite internet low-orbit satellite group 03 uses Ka and other frequency band payloads, mainly providing users with broadband communication, Internet access and other services. So far, through three network launches, China Star Network’s low-orbit business satellites have been launched into orbit with 29 satellites.
The Long March 5B/Long March 5B (LM-5B/CZ-5B) is a large cryogenic liquid carrier rocket developed by the First Academy of China Aerospace Science and Technology Corporation. The four boosters are developed by the Eighth Academy of China Aerospace Science and Technology Corporation. The entire rocket adopts a one-and-a-half-stage configuration, with the core stage and four boosters bundled together. The rocket is developed based on the basic model of the Long March 5 series, the Long March 5, and is developed by removing the core stage and making adaptive improvements on the basis of the Long March 5, for low-Earth orbit launch missions.
The “Long March 5B” rocket is 53.657 meters high, with a core diameter of 5 meters and a booster diameter of 3.35 meters. It is equipped with a large fairing with a diameter of 5.2 meters and a length of 20.5 meters. The takeoff mass is about 849 tons and the takeoff thrust is about 1074 tons. The rocket has a near-Earth orbit (LEO) capacity of more than 25 tons with a perigee of 200 kilometers, an apogee of 400 kilometers and an inclination of 19.5 degrees. In Asia, the “Long March 5B” is the rocket with the strongest near-Earth transport capacity in service. Based on its large transport capacity and large space, the “Long March 5B” is a scarce rocket model for constellation network launches.
This launch mission implemented a zero-window launch, and the rocket booster air pipe connector was changed to a plug-in connector that can be detached in 0 seconds, which improved the separation reliability. In addition, the booster of this rocket used an integral bottom liquid oxygen tank for the first time. The tank was upgraded from the “block forming + component welding” production mode to an integrated tank bottom production mode. Only a single booster reduced 14 welds totaling 24 meters, improving product production efficiency and reliability.
The “Yuanzheng-2” (YZ-2) upper stage is a space transfer vehicle developed by the First Academy of China Aerospace Science and Technology Corporation. It is mainly used to perform direct launch missions into low, medium and high Earth orbits in combination with the “Long March 5” series of launch vehicles. The “Yuanzheng-2” is equipped with two YF-50D engines, using nitrogen tetroxide/uniform dimethylhydrazine room temperature propellants. The vacuum thrust of a single engine is about 0.66 tons, the vacuum specific impulse is about 316 seconds, and it can be restarted twice. The working time of this upper stage is more than 6.5 hours.
When carrying out the constellation network launch mission, the Long March 5B will send the upper stage satellite assembly into suborbital, and the upper stage will quickly send the satellite directly into orbit, and the rocket core stage will achieve controlled deorbit. According to the plan, the Long March 5B will carry out multiple constellation network launch missions.
This mission is the first launch of the Long March 5B carrier rocket in 2025, the third launch from the Wenchang Launch Center, the 24th launch in China and the 88th orbital space launch in the world.
Images and visuals are from their Respectives CMS China Manned SpaceCNSA-China National Space Administration
