The Yaogan-30 high-revisit constellation

This article initially appeared on eastpendulum.com, a French-language blog about the Chinese military and aerospace industry

On November 24th, 2017, a Chinese CZ-2C rocket launched a trio of spy satellites. The payload was designated Yaogan-30-02, and was injected into a 600km orbit with a 35° inclination.

The Yaogan-30-01 trio

Although China is relatively open about its military launches, not much is known about the Yaogan-30 satellites, which are a new addition to the Chinese reconnaissance system. On September 29, 2017, a first trio was launched in a similar orbit, under the designation Yaogan-30-01. China described the purpose of the satellites as being to “carry out technological experiments on electromagnetic environments“, which sounds like an euphemism for signal intelligence.

Indeed, satellite triplets are often used for signal intelligence, for instance in the American NOSS constellation or China’s own Yaogan-16, -17, -20 and -25 triplets. The advantage of…