China launches sixth navigation satellite
China has launched the sixth satellite in their growing navigation system on Sunday, via the launch of their Long March 3C (Chang Zheng-3C) launch vehicle, carrying the BeiDou-2 Compass-G4 satellite. The launch of took place from the Xi Chang Satellite Launch Center, in Sichuan Province at 16:26UTC on October 31.
China’s constellation of satellites for the navigation system will eventually consist of 35 vehicles, including 27 MEO satellites, 5 GSO satellites and 3 IGSO birds. 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 BeiDou-2 was developed in the basis of the DFH-3 satellite platform and is expected to have a lifespan of eight years.
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 be 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 GPS and GLONASS.
Like the American and Russian counterparts, CNSS will have two levels of service, ranging from a civilian service which will allow for 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 users service, providing higher accuracies.
The first phase of the project will involve coverage of the Chinese territory, with the second phase covering the entire globe.
Previous BeiDou satellites for the second-generation satellite navigation system were launched on April 13, 2007 ‘Compass-M1′ (31115 2007-011A); April 14, 2009 ‘Compass-G2′ (34779 2009-018A); January 16, 2010 ‘Compass-G1′ (36287 2010-001A); June 2 ‘Compass-G3′ (36590 2010-024A) and July 31, ‘Compass-I1′ (36828 2010-036A).
This was the sixth flight of the CZ-3C Chang Zheng-3C launch vehicle. The vehicle 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.
The development of the CZ-3C started in February 1999. The rocket has a liftoff mass of 345,000 kg. The first two stages and the two strap on boosters use hypergolic (N2O4/UDMH) fuel, while the third stage uses cryogenic LOX. The total length of the CZ-3A is 54.838 meters, with a diameter of 3.35 meters on the core stage and 3.00 meters on the third stage.
The first launch of the CZ-3C Chang Zheng-3C launch vehicle took place on April 25, 2008 when it orbited the first TL-1 Tian Lian-1 tracking and data relay satellite.
This was the 134th successful Chinese orbital launch, the 133rd launch of a Chang Zheng launch vehicle, the sixth launch from Xi Chang in 2010, the 12th orbital launch for China in 2010, establishing a new total launch record for a year.
The Xi Chang Satellite Launch Centre 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 centre has a dedicated railway and highway lead directly to the launch site. The Command and Control Centre 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. Each of them houses tracking and measurement equipment for the powered phase of a launch vehicle flight.
Other facilities on the Xi Chang Satellite Launch Centre are the Launch Control Centre, 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.
Before the end of the year China plans other launches as the launch of the FY-3B Feng Yun-3B meteorological satellite, on November 4, the launch of the ST-1B Shen Tong-1B / ZX-20 (2) ZhongXing-20 (2) military communications satellite, and another launch for the Compass navigation system with the launch of the second BeiDou-2 IGSO (Inclined GSO) satellite of the system.