On Friday, April 18, China successfully launched six experimental Shiyan series satellites into orbit. The launch utilized the Long March 6A rocket, which lifted off from the Taiyuan Satellite Launch Center in northern China at 6:51 p.m. Eastern Time (2251 UTC).
The Shanghai Academy of Spaceflight Technology (SAST) confirmed the launch's success, identifying the payloads as Shiyan-27 (01-06). SAST described the satellites' primary function as space environment detection and related technical tests—a typical description for the Shiyan series, often viewed by Western analysts as a platform for testing new technologies in the early stages of space system development. This is somewhat similar to how the U.S. military employs USA-designated satellites for classified technology demonstrations.
The U.S. Space Force tracked the satellites in 1,000 by 1,010-kilometer-altitude orbits with a 99.7-degree inclination. The rocket's upper stage was left in an 834 by 990 km orbit. While many Shiyan satellites operate in low Earth or near-polar orbits, some have been deployed to geosynchronous orbits, notably the potential inspector satellites Shiyan-12-01 and 02. Shiyan-10 satellites, conversely, have been placed in Molniya orbits.
The Long March 6A, a 50-meter-long, 530-metric-ton rocket developed by SAST, is unique for its combination of a liquid propellant core stage and solid propellant side boosters. It's capable of launching 4,500 kilograms to a 700-kilometer sun-synchronous orbit and has a dedicated launch pad at Taiyuan. This launch marked its 11th flight since its debut in March 2022, maintaining a perfect launch record despite some upper stage disintegration incidents leading to orbital debris in past missions.
SAST highlighted Friday's launch as the first to utilize "multi-satellite wall-mounted deployment," a method that involves mounting satellites around a central structure rather than stacking them vertically. SAST noted that this approach presented significant integration challenges.
This launch represents China's 20th orbital launch attempt of 2025, following the April 10 launch of the classified TJS-17 satellite via a Long March 3B rocket from Xichang. Subsequent observations by Slingshot Aerospace indicated a likely apogee kick motor near geostationary orbit, mirroring the trajectory of the TJS-15 launch.
Looking ahead, China is preparing for the Shenzhou-20 crewed mission (Long March 2F rocket from Jiuquan) next week, followed by Shenzhou-21 later in the year. A significant upcoming mission is the Tianwen-2 near-Earth asteroid sample return and main belt comet rendezvous mission, scheduled for launch from Xichang in May.