China deploys more surveillance satellites

China successfully deployed three Yaogan-31 observation satellites on 13 March, with the orbits they were placed in suggesting they are part of the Jianbing-8 constellation of ocean surveillance satellites.

The Yaogan (meaning ‘remote sensing’) satellites were carried into orbit by a Long March 4C rocket that took off from the Jiuquan Satellite Launch Centre in the Gobi Desert in northwestern China. They are the fourth group of Yaogan-31 satellites to be deployed, with each group containing three satellites.

Previous Yaogan-31 satellites have been described by Chinese state-owned media as being designed to “conduct electromagnetic environmental monitoring and related technology tests”. However, such broad or generic functions are often ascribed to satellites that are considered to have a military function.

On 13 March China launched into space the fourth group of three Yaogan-31 remote-sensing satellites aboard a Long March 4C rocket that took off from the Jiuquan Satellite Launch Centre. (Via PLA Daily)

The recently deployed satellites are believed to be for electronic intelligence (ELINT) exploitation, designed to intercept the radar and communications system emissions of ships. The satellites in each triplet group are positioned in close proximity so that the location of the transmitting ship can be determined by triangulation, measuring the difference in a signal’s time of arrival at each satellite.

The first group – known as Yaogan-31-01 – was launched on 10 April 2018, the second one – Yaogan 31-02 – was deployed on 29 January 2021, and the third – Yaogan 31-03 – was placed into orbit on 24 February.