China launched another commercial satellite mission on Monday, when a Long March 3B/E (Chang Zheng-3B/E) lofted the NigComSat-1R on behalf of Nigeria from the Xixhang satellite Launch Center. The launch – adding to China’s record year – took place at 16:41 UTC.
Chinese Commercial Launch:
NigComSat-1R is built on DFH-4 satellite bus developed by the China Academy of Space Technology (CAST), a subsidiary of China Aerospace Science and Technology Corporation (CASC), and is equipped with 28 transponders on board, including 4 C-band, 14 Ku-band, 8 Ka-band, 2 L-band.
The satellite will be positioned at 42.5 degrees East Longitude, has a lift-off mass of 5,100 kg – and a service lifespan of 15 years.
The satellite, covering Central Western and Southern Africa, Central and Eastern Europe, and some Central Asia area, will be mainly applied to communications, broadcasting, tele-education, broad band multimedia service, navigation service and so on, which will improve the national infrastructure and benefit the people in rural areas.
To further extend the operation and marketing of NigComSat-1R, Ku Kashi Beam was added to NigComSat-1R. The Satellite will supply the communications between Nigeria and China. Moreover, the utilization of satellite capacity will be enhanced without additional extra cost.
Projected orbital injection parameters are 200 km perigee, 41.991 km apogee and 24.8 degree inclination.
China’s 17th launch in 2011 was also the 154th successful Chinese orbital launch, the 154th launch of a Chang Zheng launch vehicle, the 9th launch from Xichang in 2011 and the 68th orbital launch from Xichang. This was the 18th space launch for China this year.
In December 2004 the Nigerian Communications Satellite Limited (NIGCOMSAT LTD) signed a contract with China Great Wall Industry Corporation (CGWIC) for the design, manufacture and launch of the NigComSat-1 (Nigerian Communication Satellite-1). The satellite was based on the DFH-4 platform and was equipped with 4 C-band, 14 Ku-band, 8 Ka-band and 2 L-band transponders.
The satellite was successfully launched on May 13, 2007 on the Z-3B/E Chang Zheng-3B/E (Y9) booster from the LC2 launch platform of the Xichang launch center. In April 2008, NigComSat-1 lost power from the southern solar array and the satellite eventually failed in November 2008 due to a technical error of the satellite’s northern solar array and was sent to a graveyard orbit as it became apparent, that the satellite could not be recovered.
The Nigerian Communications Satellite 1R Contract was signed between NIGCOMSAT LTD and CGWIC on March 24, 2009. Pursuant to the Contract, CGWIC, with its subcontractor China Academy of Space Technology (CAST), China Academy of Launch Vehicle Technology (CALT), and China Satellite Launch & Tracking Control General (CLTC) contributed for the NigComSat-1R launch and deliver it in orbit.
Nigerian Communications Satellite Limited was incorporated as a limited liability company in April 2006, which is a state-owned enterprise responsible for the operation and management of Nigerian Communications Satellites.
The NigComSat-1R, the replacement satellite of NigComSat-1, is the fourth in-orbit delivery contract for communications satellite signed between CGWIC and international customers. By identifying the problem and analyzing the failure mode, numbers of improvements based on tests and experiments have been applied to follow-on satellite programs, and the reliability of satellite has been enhanced constantly.
Furthermore, China Aerospace Science and Technology Corporation (CASC) and its relevant organizations reached a decision to build and launch NIGCOMSAT-1R with no extra cost to Nigerian customer.
NigComSat-1R paves the way for the international marketing development of China Aerospace and further confirms the friendship between Nigerian and China.
The DFH-4 (DongFangHong-4) platform is a large telecommunications satellite platform of new generation, it keeps high capability in output power and communication capacity ranking with international advanced satellite platforms. The applications for the DFH-4 platform aren’t limited to high capacity broadcast communication satellites and can be used to tracking and data relay satellites, regional mobile communication satellites, etc.
The platform comprises propulsion module, service module and solar array. It has a payload capacity of 588 kg and an output power of 10.5 kW by the end of its lifetime. Its design lifetime is 15 years and its reliability by the end of lifetime is more than 0.78. Based on versatility, inheritance, expandability and promptness principles and mature technology, the platform will reach world advanced level to meet the needs of international and domestic large communication satellite markets.
Generally DFH-4 based satellites are equipped with 22 Ku-band transponders (four 54MHz and 18 36MHz), 3 receiver antennas and 2 transmission antennas. With a designed operational life of 15 years, the DFH-4 can support the transmission of 150~200 TV programs simultaneously to ground users using a 0.45 meter antenna device. The DFH-4 satellite also features strong capabilities against hostile disturbance and jamming. The satellite’s power supply includes two 6 meter solar panels.
Launch sequence:
The fuelling of the third stage with LOX and LH2 starts at L-7 hours. First and second stages as well as the four strap-on boosters use hypergolic propellant fuelled earlier.
At L-1h 20m is the launch vehicle control system power on and function checkout followed by the telemetry system power on and function checkout. At L-40m the fairing air-conditioning is turned-off and the air-conditioning pipe is dropped-off. Technicians also proceed with the flight program loading and check-up. The gas pipes for the first stage second and are dropped-off.
The pre-cooling of the third stage engines takes place at L-20m and at L-13m takes place the third stage propellants topping. Between L-15m and L-10m the spacecraft umbilical disconnection takes place and at L-3m the telemetry and tracking systems power is switch-over and the third stage propellant fueling pipe is disconnected.
The disconnection of the gas pipe for the third stage is disconnected at L-2m followed by the control system power switch-over at L-1m 30s. Control system, telemetry system and tracking system umbilical disconnection take place at L-1m as well as the swinging-off of the rods. The TT&C systems start at L-30s and ignition comes at L-0s.
Eleven seconds after lift-off takes place the pitch-over maneuver. Boosters separation occurs at T+2m 21s followed at T+2m 39s by the separation between the first and second stages. Fairing jettison comes at T+3m 55s. Separation between the second and third stage takes place at T+5m 44s, with the third stage igniting for the first time. This burn ends at T+10m 12s.
The vehicle is now on a preliminary orbit until T+20m 56s when the third stage starts its second burn. This burn will last for 3 minutes and 6 seconds, ending at T+24m 2s. After the third stage shutdown takes places at T+24m 22s an attitude adjustment before spacecraft separation at T+25m 42s.
The companies:
Established in 1980, China Great Wall Industry Corporation (CGWIC) is the sole commercial organization authorized by the Chinese government to provide satellites, commercial launch services and to carry out international space cooperation.
As the professional company promoting international cooperation for China’s space industry, CGWIC is devoted to the internationalized development of China’s space industry. CGWIC has developed into a system integrator for space products and services.
It can meet customer’s multi-directional needs by providing comprehensive solutions for commercial launch services, satellite export, satellite ground tracking and control station construction, satellite applications, project financing, project insurance and technical training, etc. Through extensive international cooperation, CGWIC enjoys an excellent reputation in the international aerospace industry, the financial community and the insurance circle.
In addition, CGWIC is actively involved in the international marketing of civilian products and services utilizing space technology and provides high quality products and specialized services in diversified fields including satellite technology applications, green energy, information & electronic products, petroleum & petrochemical equipment, new materials, consulting services, international trade, international exhibition, international logistics, project contracting, international bidding, etc.
The Company Nigerian Communications Satellite (NIGCOMSAT) Limited was incorporated on April 4, 2006 as a company under the auspices of the Federal Ministry of Science and Technology. The company mission is “to manage and exploit the commercial viability of the Nigerian Communication Satellite for the social economic benefit of the nation”. The company is charged with the management and operation of the first geostationary communications satellite in sub-Sahara Africa.
Launch vehicle:
Developed in the basis of the CZ-3A Chang Zheng-3A, the CZ-3B Chang Zheng-3B is the most powerful launch vehicle on the Chinese space launch fleet.
The CZ-3B features enlarged launch propellant tanks, better computer systems, a larger 4.2 meter diameter payload fairing and the addition of four strap-on boosters in the core stage that give an additional help in the first phase of the launch. The rocket is capable of launching a 11,200 kg satellite to a low Earth orbit or a 5,100 kg cargo to a geosynchronous transfer orbit. The rocket has a total length of 54.84 meters and a core diameter of 3.35 meters.
The first launch of the CZ-3B took place on February 14, 1996, but ended in failure in what is now known has the “St. Valentine’s Day Massacre”. (Raw video available on L2).
This was caused by the first CZ-3B failing two seconds after liftoff before crashing in a near by village killing dozens of people. The first successful launch took place on August 19th, 1997 when the second CZ-3B orbited the Agila-2 ‘Mabuhay’ (24901 1997-042A) communications satellite.
In recent years, the CZ-3B/E (Enhanced Version) launch vehicle was developed on the basis of CZ-3B, increasing the GTO capacity up to 5,500kg. The CZ-3B/E has nearly the same configurations with CZ-3B except its enlarged core stage and boosters.
On May 14, 2007, the first flight of CZ-3B/E was performed successfully, accurately sending the NigcomSat-1 into pre-determined orbit. With the GTO launch capability of 5,500kg, CZ-3B/E is dedicated for launching heavy GEO communications satellite.
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. The CZ-3B launch pad is located at 28.25 deg. N – 102.02 deg. E and at an elevation of 1,825 meters.
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.
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.
(Images: NTAi TV, L2 and Nigcomsat.