2012-05-27 (China Military News cited from nasaspaceflight.com and by Rui C. Barbosa) — A new military communications satellite – the Zhongxing-2A (Chinasat-2A) – was launched by a Chang Zheng-3B (Y17) (Long March 3B) launch vehicle on Saturday. Lift off from the Xichang Satellite Launch Center LC2 launch complex took place at 15:56 UTC.
The Chinasat-2A satellite was built on the DFH-4 platform, with a launch mass around 5,200 kg. It was manufactured by the China Great Wall Industry Corporation (CGWIC).
Due to its military nature, there is little technical information on the satellite. However, China use two types of satellites for secure military communications: the Fenghuo and the Shentong.
The Fenghuo series is used for tactical military communications, providing secured digital data and voice communication to Chinese military forces.
The Chinese are currently operating the DFH-4 based Fenghuo-2 second generation satellite, with the first of the series – the ZX-1A Zhongxing-1A (37804 2011-047A) – launched at 13:33 UTC on September 18th, 2011, by the Chang Zheng-3B (Y16) rocket.
The Shentong geostationary military communication satellites are operated by the Army and their aim is to provide secured voice and data communications services for ground users using Ku-band. The satellite was based on the DFH-3 (Dongfanghong-3) satellite platform that was developed by the China Academy of Space Technology (CAST), having a heavier payload with better reliability and increased power supply.
Chinasat-2A will be the first of a second generation DFH-4 based Shentong-2 satellite in operation.
To meet demand of international satellite launch market, especially for high power and heavy communications satellites, the development of Chang Zheng-3B launch vehicle was started in 1986 on the basis of the fight proven technology of Long March launch vehicles. The Chang Zheng-3B is the most powerful launch vehicle on the Chinese space launch fleet.
Each of the four boosters has a 15.326 meter length with a 2.25 meter diameter, consuming 37,700 kg of N2O4 / UDMH. Equipped with a YF-25 engine capable of a ground thrust of 740.4 kN and a ground specific impulse of 2,556.2 Ns/kg.