China… Communication Portal Takes Off (Satellite)

[SatNews] This is the second tracking and relay satellite for China…

Rui C. Barbosa has posted, on the NASASpaceflight.com site, an info piece regarding a new Chinese satellite. The article states this is an important step for the next phase of the country’s manned space program. China launched its second tracking and data relay satellite, Tian Lian-1B (TL-1B). The launch took place at 15:41 UTC on Monday from the Xi Chang Satellite Launch Center, in Sichuan Province, using a Long March 3C (Chang Zheng-3C) launch vehicle.

The launch of Tian Lian-1B anticipates the high point for the Chinese Space Program this year, the launch of TG-1 TianGong-1 and SZ-8 Shenzhou-8. These two unmanned vehicles will attempt, for the first time in Chinese spaceflight history, to dock in orbit. This is an important step ahead of the launch of SZ-9 with its three person crew, which are scheduled to dock with TG-1. The Chinese tracking and data relay satellite was developed by the China Academy of Space Technology (CAST). It is similar to the American Tracking and Data Relay Satellite System (TDRSS) in concept. The system is designed to support near-real-time communications between orbiting spacecraft and the ground control, and will complement the ground-based space tracking and telemetry stations and ships to support future space projects

Like its predecessor, Tian Lian-1A, the Tian Lian-1B satellite is based on the DFH-3 bus. The DFH-3 (DongFangHong-3) platform is a medium-capacity telecommunications satellite platform also designed and developed by CAST (Chinese Academy of Space Technology). The platform can carry multiple telecommunications payloads for providing numerous services, such as fixed communication, international satellite communication, national and regional communication, wide-band data communication, mobile communication and direct broadcast; military communication, spacecraft tracking and data relay, etc.

The platform comprises six subsystems: control, power, propulsion, measurement and control, structure and thermal control subsystem. It’s configuration features a module subdivision, which includes communication module, propulsion module, service module and solar array. The platform adopts a three-axis stabilized attitude control mode, with solar array output power of 1.7 kw by the end of its design lifetime of 8 years. Its mass is 2,100kg with payload capacity 220kg.

The satellite platform has been successfully applied in the DFH-3 satellite, Beidou navigation test satellite, and other satellites, all of which are currently operating normally. This was the seventh flight of the CZ-3C Chang Zheng-3C launch vehicle. This rocket was developed to fill the gap between the CZ-3A Chang Zheng-3A and the CZ-3B Chang Zheng-3B, having a payload capacity of 3,800 kg for GTO. This is a three stage launch vehicle identical to the CZ-3B but only using two strap-on boosters on its first stage. CZ-3C provides two types of fairing and two kinds of fairing encapsulating process and four different payload interfaces, which is the same as CZ-3B launch vehicle. The various fairing and interface adapter and the suitable launch capacity make CZ-3C a good choice for user to choose the launch service.