At 18:00 on November 23, 2023, the carrier system formed by Long March 2D launch vehicle/Yuanzheng-3 upper stage was launched at Xichang Satellite Launch Center, and successfully placed a satellite internet technology test satellite into the scheduled orbit, signaling a complete success of the launch mission.

This launch mission is the 84^th launch of the Long March 2D launch vehicle, the 2^nd launch of the Yuanzheng-3 upper stage, the 202^nd launch of the Long March series of launch vehicles developed by Shanghai Academy of Spaceflight Technology, and the 498^th launch of the Long March series of launch vehicles. Both the launch vehicle and the upper stage are developed by Shanghai Academy of Spaceflight Technology. The satellite is developed by Shanghai Academy of Spaceflight Technology and the Innovation Academy for Microsatellites of Chinese Academy of Sciences.

The mission marks the return of Yuanzheng-3 upper stage after a five-year hiatus, and this is also its first mission carried out at the Xichang Satellite Launch Center. Yuanzheng-3 upper stage possesses the capability for autonomous orbital maneuvers, with orbital flight duration of up to 48 hours. It is equipped with a pressure-fed engine which has a thrust of 5 kN, capable of more than 20 ignition maneuvers. The upper stage can autonomously plan the optimal flight path based on the orbital status at the time of its separation from the launch vehicle, and execute the deployment of multiple satellites on disparate orbits and supplemental constellation network deployment on low to medium Earth orbits. With a modular and standardized design, Yuanzheng-3 upper stage can be used with multiple types of launch vehicles, significantly enhancing China’s ability for rapid and flexible space entry, transfer, and utilization.

On December 29, 2018, the Long March 2D launch vehicle which carries the Yuanzheng-3 was successfully launched from the Jiuquan Satellite Launch Center. After four precise orbital transfers within 4 hours, Yuanzheng-3 successfully placed two sets of 7 satellites into the scheduled orbits with a height difference of several hundred kilometers separately, marking a complete success of its maiden flight mission.

To further improve the carrying capacity of the launch system, in this mission, the Yuanzheng-3 upper stage and Long March 2D launch vehicle adopted a joint flight method for the first time, resembling the three sub-stages of a three-stage launch vehicle. Different from the maiden flight mission, when the Long March 2D launch vehicle placed the combination of Yuanzheng-3 upper stage and satellite into a circular orbit at a height of 200 km, in this mission, the upper stage and the launch vehicle were separated at the suborbital trajectory. Within 3 seconds after the separation, the upper stage successfully placed the satellite into the target orbit after the first ignition into the orbit and a second ignition to the scheduled orbit. After that, the upper stage actively departs from the orbit under control after two additional ignitions.

In this mission, the Long March 2D launch vehicle adopted a 4-meter diameter fairing for the first time at the Xichang Satellite Launch Center. The model team accurately identified and prevented the risks through careful planning, and conducted a series of tasks including the retest of the coordination between the launch vehicle and the tower, retest of payload strength, and retest of the control system, which effectively ensured the success of the flight mission.