China kicks off their big 2011 push with BeiDou-2 launch

by Rui C. Barbosa

The first Chinese launch in 2011 took place at 20:47UTC on Saturday (April 9), as their Chang Zheng-3A (Long March 3A) launch vehicle orbited the third BeiDou-2 a navigation satellite, following lift-off from the Xi Chang Satellite Launch Center, in Sichuan Province. China is planning around 20 missions in 2011.

Chinese Launch:

This constellation of satellites – developed in the basis of the DFH-3 satellite platform and have a lifespan of eight years – will consist of 35 vehicles, including 27 MEO satellites, 5 GSO satellites and 3 IGSO. The satellites will transmit signals on the: 1195.14-1219.14MHz, 1256.52-1280.52MHz, 1559.05-1563.15MHz and 1587.69-1591.79MHz, carrier frequencies.

The Compass Navigation Satellite System (CNSS) is China’s second-generation satellite navigation system capable of providing continuous, real-time passive 3D geo-spatial positioning and speed measurement. 

The system will initially used to provide high-accuracy positioning services for users in China and its neighboring regions, covering an area of about 120 degrees longitude in the Northern Hemisphere. The long-term goal is to develop a global navigation satellite network similar to the US GPS and Russian GLONASS systems.

Like the American and Russian counterparts, CNSS will have to kinds of services: a civilian service that will give an accuracy of 10 meters in the user position, 0.2 m/s on the user velocity and 50 nanoseconds in time accuracy; and the military and authorized user’s service, providing higher accuracies.

The first phase of the project will be focused on the coverage of the Chinese territory, but in the future the Compass constellation will cover the entire globe.

The previous BeiDou launch took place on December 17th when a Chang Zheng-3A orbited the ‘Compass-I2’ (37256 2010-068A) satellite. That was the twentieth flight of the CZ-3A Chang Zheng-3A launch vehicle.

The CZ-3A is a three-stage liquid launch vehicle, which has inherited the mature technology of the CZ-3 Chang Zheng-3. An upgraded liquid hydrogen and liquid oxygen cryogenic third stage has been developed to enable CZ-3A performing greater geostationary transfer orbit (GTO) capability.

The CZ-3A is equipped with a more flexible and sophisticated control system which supports substantial attitude adjustments to orient the payloads before spacecraft separation and provides adjustable satellite spin-up rotation rate. It has paved the way for the development of CZ-3B Chang Zheng-3B and CZ-3C Chang Zheng-3C, and become the basic type of GTO launch vehicles.

The CZ-3A is mainly used for GTO missions; it also can be used for LEO, SSO and polar orbit missions, as well as dual-launch and multiple-launch missions. The launch capacity of the CZ-3A to GTO is 2,650 kg, the lift-off mass is 241,000 kg, the overall length is 52.5 meters, the diameter of first stage and second stage is 3.35 meters, the diameter of third stage is 3.0 meters, and the maximum fairing diameter is 3.35 meters.

The first stage and second stage of CZ-3A employ storable propellants, i.e. unsymmetrical dimethy1 hydrazine (UDMH) and nitrogen tetroxide (N204), and the third stage uses cryogenic propellants, i.e. liquid hydrogen (LH2) and liquid oxygen (LOX).

Chinese Space Flight Specific Articles:

On the first stage the CZ-3A uses a DaFY6-2 engine with a 2961.6 kN thrust, while the second stage is equipped with a DaFY20-1 main engine (742 kN) and four DaFY21-1 vernier engines (11,8 kN each). The third stage is equipped with two YF-75 engines (78.5 kN each). The fairing diameter of the CZ-3A is 3.35 meters and has a length of 8.89 meters.

CZ-3A consists of rocket structure, propulsion system, control system, telemetry system, tracking and safely system, coast phase propellant management and attitude control system, cryogenic propellant utilization system, separation system and auxiliary system, etc.

The launch success rate of CZ-3A is 100 percent since its maiden flight on February 8, 1994 when it successfully launched two experimental satellites (the Shi Jian-4 and the Kua Fu-1, a DFH-3 model). And it was awarded the “Gold Launch Vehicle” title by China Aerospace Science and Technology Corporation in June 2007.

This was the 138th successful Chinese orbital launch, the 137th launch of a Chang Zheng launch vehicle, the first launch from Xi Chang in 2011, and the first orbital launch for China in 2011.

The Xi Chang Satellite Launch Center is situated in the Sichuan Province, south-western China and is the country’s launch site for geosynchronous orbital launches.

Equipped with two launch pads (LC2 and LC3), the center has a dedicated railway and highway lead directly to the launch site. The Command and Control Center is located seven kilometers south-west of the launch pad, providing flight and safety control during launch rehearsal and launch. Down range Tracking and Control stations of the launch center are located in Xi Chang City and Yibin City of Sichuan Province, and Guiyang City of Guizhou Province.

Other facilities on the Xi Chang Satellite Launch Center are the Launch Control Center, propellant fuelling systems, communications systems for launch command, telephone and data communications for users, and support equipment for meteorological monitoring and forecasting.

During 1993-1994 Xi Chang underwent extensive modernization and expansion, in part due to the requirements of the CZ-3 launcher family and in part to meet commercial customer needs.

The first launch from Xi Chang took place at 12:25UTC on January 29, 1984, when the CZ-3 Chang Zheng-3 (CZ3-1) was launched the Shiyan Weixing (14670 1984-008A) communications satellite into orbit. The launch of the new BeiDou-2 satellite was the 52nd successful orbital launch from Xi Chang.

2011, a new Chinese year in space:

With the Space Shuttle retiring in June, Russia will effectively taking over as the world’s leader in space via its global frequency of launches and manned space flight capability to the International Space Station (ISS).

However, China has one eye on second place as it ramps up its launch schedule, which includes the lofting of the TG-1 TianGong-1 Space Station in the middle of the year. Soon after, Shenzhou-8 will be launched unmanned to test the rendezvous and docking procedures on a multiple week mission. If everything goes according to plan, manned flights will follow with Shenzhou-9 and Shenzhou-10 in 2012.

The docking of TianGong-1 with Shenzhou-8 is regarded as an essential step toward building a space station. China aims to complete construction of a relatively large manned space laboratory around 2020, developing and launching the first part of a space laboratory before 2016, focusing on breakthroughs in living conditions for astronauts and research applications.

As previously announced, this project is the finish line of the three-step manned space program, that involved the developing the Shenzhou spaceships, then technologies needed for docking and extra-vehicular activities, that is currently underway, and finally the construction of the space station.

Tiangong-1, can eventually be transformed into a manned space laboratory after experimental dockings with Shenzhou-8, Shenzhou-9 and Shenzhou-10 spacecraft, with the last two carrying two or three astronauts each.

China also wants to firmly mark its position on the international launch market with the launch of three commercial missions this year, namely the Eutelsat-W3C, the PakSat-1R and the NigComSat-1R, communications satellites. PakSat-1R and NigComSat-1R, for Pakistan and Nigeria respectively, are both based on the DFH-4 satellite platform.

China and Brazil is also continuing the mutual cooperation via the launch of the CBERS-3 remote sensing satellite. This launch was, however, delayed to 2012.

Related Articles