11.04.2017
China to launch Shijian-13 experimental sat on Wednesday
Shijian-13 will be launched to geostationary orbit on a Long March 3B rocket from the Xichang Satellite Launch Centre, southwest China, at around 7pm Beijing time on April 12 (11am UTC), according an airspace restriction notice.
The 4.6-tonne satellite is set to be positioned at 110.5E, from where it will provide Ka-band satellite broadband and multimedia services to mainland China and other areas with a message capacity of more than 20 Gbps.
Shijian-13 will also carry out space-to-ground laser communications experiments, which could pave the way to much greater advances in satellite communications capacity.
The satellite has a design lifetime of 15 years and will mark the first full use of China's LIPS-200 xenon ion engines for propulsion.
Using ion engines instead of heavy conventional chemical fuels can allow a satellite to carry greater payloads or reduce launch costs.
The engines were developed by the Lanzhou Institute of Physics (LIP) and were first tested on Shijian-9A, launched in October 2012.
Above: A Long March 3B launches Belintersat-1 from Xichang in January 2016.
Following on-orbit testing, the Shijian-13 ('practice-13') satellite will be designated as Zhongxing-16 (Chinasat-16).
The satellite, based on the DFH-3B platform, was manufactured by the China Academy of Space Technology (CAST) and is planned for use in distance learning, medicine, internet access, airborne and maritime communications, and emergency communications.
Launch on Wednesday would be China's fourth orbital mission of 2017, following TJS-2, a Kuaizhou-1A rocket launch, and Tiankun-1.
The China Aerospace Science and Technology Corporation (CASC), the main contractor for the Chinese space programme and of which CAST is a subsidiary, is aiming for close to 30 launches in 2017, with further solid-fuelled rocket launches of small satellites also expected for another state-run space actor, CASIC.
China's busy April
Launch of Shijian-13 will kick off a very busy month for the Chinese space programme, which will see a major mission, a national space day and the revealing of a name and logo for the country's 2020 Mars mission.
The main business will be Tianzhou-1, the first test of cargo spacecraft that marks a crucial step towards constructing a space station.
Tianzhou-1 will launch from the new coastal Wenchang Satellite Launch Centre on the second Long March 7 carrier rocket, and, once in orbit, dock with Tiangong-2, with the main aim of testing and proving liquid propellant refuelling technologies in microgravity.
Tianzhou spacecraft, much like Russian Progress or American Cygnus resupply craft, will be required to keep the future Chinese Space Station (CSS) fuelled and its astronauts fully sustained and supplied.
Preparations for launch are being finalised on Hainan Island, and the Yuanwang-7 tracking ship has started its maritime space monitoring and communication tasks ready for the mission.
Current rumours and projections suggest a launch for either April 20 or 23 and live streams of the launch will be available.
Above: Tianzhou-1 undergoing testing at the AIT centre in North China.
On April 24, the anniversary of the launch of the country’s first satellite (Dongfanghong-1) in 1970, China will host its second national ‘Space Day’, as part of space and science education outreach, and seeking to secure political rewards for the ruling Communist Party for major achievements.
The occasion will also be used to announce the winners of a public competition to both name and create a logo for China’s 2020 Mars mission, which includes an orbiter, lander and rover.
A competition to give a more attractive name to the Hard X-ray Modulation Telescope (HXMT), a space science mission which launches in June, will also close.
Further telecommunications launches
In June China will launch Shijian-18, the first test of the new DFH-5 satellite bus. With a mass of up to 7 tonnes, the new platform requires the heavy-lift Long March 5 to loft it to nearly 36,000 km above the Earth.
The mission will be the second for the new carrier rocket, with China hoping for a less dramatic launch than its ultimately successful debut in November.
Zhongxing-9A is another planned summer comms sat launch, which will see the DFH-4 bus based Ku-band satellite sent to 92° E in geostationary orbit on a Long March 3B/E from Xichang.
China aims to use DFH-4 and -5 satellite platforms to make the internet available in aircraft cabins, high speed trains and even remote mountainous areas by 2025.
Other communications satellites planned for launch this year, according to Nasaspaceflight.com, are Zhongxing-6C around September and an international contracted launch, Alcomsat-1, for Algeria.
Above: A model DFH-4E satellite bus on display at Zhuhai Air Show in 2012.
Quelle: gbtime
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Update: 12.04.2017
Long March 3B launches experimental ChinaSat-16 satellite
The Chinese returned to launch action with the lofting of a new experimental communications satellite from the Xichang Satellite Launch Center. The launch was conducted by the Long March 3B G2 ‘Chang Zheng-3B/G2’ (Y43) from the LC2 Launch Complex at the Sichuan province site, with T-0 noted as 11:04 UTC.
Chinese Launch:
The 4.6-tonne satellite was developed by the China Academy of Space Technology (CAST) and is based on the DFH-3B satellite platform. According to state media reports, the satellite will be named Shijian-13 during its test program phase, before being renamed ChinaSat 16 when it is transferred to China SatCom.
The new satellite will test a new electric propulsion system to be used for orbit raising and station keeping at a geosynchronous altitude. It also carries the first high-throughput satellite payload (HTS) developed by China.
The satellite features a Ka-band broadband communications system capable of transmitting 20 gigabytes of data per second, making it the most powerful communications satellite the nation has developed to date.
According to Wang Min, deputy head of the CAST’s Institute of Telecommunication Satellite, ChinaSat-16 will provide better access to the Internet on planes and high-speed trains, with the increase in satellite throughput provided by the new satellite that will be located at 110.5° East.
The satellite is able to provide 26 user beams covering China and offshore areas – allowing it to also cover airborne and maritime communications and emergency communications, using Ka-band satellite broadband and multimedia services.
With a lifetime of 15 years, the satellite will be operated by China Satcom.
The satellite will also conduct space-to-ground laser communications experiments.
The DFH-3 (Dongfanghong-3) platform is a medium-capacity telecommunications satellite platform designed and developed by CAST.
The platform can be used for multiple telecommunications payloads for providing a range of services, including fixed communication, international satellite communication, national and regional communication, wideband data communication, mobile communication and direct broadcast; military communication, spacecraft tracking and data relay.
It comprises six subsystems: control, power, propulsion, measurement & control, structure and thermal control subsystem. The platform configuration features module subdivision, which includes a communication module, propulsion module, service module and solar array.
The platform adopts three-axis stabilized attitude control mode, with solar array output power of 1.7 kw by the end of its design lifetime. Its mass is 2,100kg with payload capacity 220kg.
The DFH-3 satellite platform has been successfully applied in the Beidou navigation test satellite, and other satellites, all of which are currently operating normally.
During numerous flight missions, the maturity and reliability of the DFH-3 platform have been proved. Moreover, it has strong expansion capacity and can be upgraded to some space exploration missions, such as meteorological satellite and lunar resource satellite services.
Its onboard Ion thrusters are designed for a wide variety of missions.
These thrusters have high specific impulses, that is, ratio of thrust to the rate of propellant consumption, so they require significantly less propellant for a given mission than would be needed with chemical propulsion.
Ion propulsion is even considered to be mission enabling for some cases where sufficient chemical propellant cannot be carried on the spacecraft to accomplish the desired mission.
Launch vehicle and launch site:
To meet the demand of international satellite launch market, especially for high power and heavy communications satellites, the development of Long March-3B (Chang Zheng-3B) launch vehicle started in 1986 on the basis of the fight proven technology of Long March launch vehicles.
Developed from the Chang Zheng-3A, the Chang Zheng-3B is at the moment the most powerful launch vehicle on the Chinese space launch fleet.
The CZ-3B features enlarged launch propellant tanks, improved computer systems, a larger 4.2 meter diameter payload fairing and the addition of four strap-on boosters in the core stage that provide additional help during 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 CZ-3B/G2 (Enhanced Version) launch vehicle was developed from the CZ-3B with a lengthened first core stage and strap-on boosters, increasing the GTO capacity up to 5,500kg.
On May 14, 2007, the first flight of CZ-3B/G2 was performed successfully, accurately sending the NigcomSat-1 into pre-determined orbit. With the GTO launch capability of 5,500kg, CZ-3B/G2 is dedicated for launching heavy GEO communications satellite.
The rocket structure also combines all sub-systems together and is composed of four strap-on boosters, a first stage, a second stage, a third stage and payload fairing.
The first two stages, as well as the four strap-on boosters, use hypergolic (N2O4/UDMH) fuel while the third stage uses cryogenic (LOX/LH2) fuel. The total length of the CZ-3B is 54.838 meters, with a diameter of 3.35 meters on the core stage and 3.00 meters on the third stage.
On the first stage, the CZ-3B uses a YF-21C engine with a 2,961.6 kN thrust and a specific impulse of 2,556.5 Ns/kg. The first stage diameter is 3.35 m and the stage length is 23.272 m.
Each strap-on booster is equipped with a YF-25 engine with a 740.4 kN thrust and a specific impulse of 2,556.2 Ns/kg. The strap-on booster diameter is 2.25 m and the strap-on booster length is 15.326 m.
The second stage is equipped with a YF-24E (main engine – 742 kN / 2,922.57 Ns/kg; four vernier engines – 47.1 kN / 2,910.5 Ns/kg each). The second stage diameter is 3.35 m and the stage length is 12.920 m.
The third stage is equipped with a YF-75 engine developing 167.17 kN and with a specific impulse of 4,295 Ns/kg. The fairing diameter of the CZ-3B is 4.00 meters and has a length of 9.56 meters.
The CZ-3B can also use the new Yuanzheng-1 (“Expedition-1”) upper stage that uses a small thrust 6.5 kN engine burning UDMH/N2O4 with a specific impulse at 3,092 m/s.
The upper stage is able to conduct two burns, having a 6.5 hour lifetime and is capable of achieving a variety of orbits. This upper stage wasn’t used on this launch.
The typical flight sequence for the CZ-3B/G2 sees the launch pitching over 10 seconds after liftoff from the Xichang Satellite Launch Centre. The boosters shutdown 2 minutes and 7 seconds after liftoff, with separation from the first stage one second later. First stage shutdown takes place at 1 minutes 25 seconds into the flight.
Separation between the first and second stage takes place at 1 minute 26 seconds, following fairing separation at T+3 minutes 35 seconds. Stage 2 main engine shutdown occurs 326 seconds into the flight, following by the shutdown of the vernier engines 15 seconds later.
Separation between the second and the third stage and the ignition of the third stage takes place one second after the shutdown of the vernier engines of the second stage. The first burn of the third stage will last for 4 minutes and 44 seconds.
After the end of the first burn of the third stage is followed by a coast phase that ends at T+20 minutes and 58 seconds with the third stage initiating its second burn. This will have a 179 seconds duration. After the end of the second burn of the third stage, the launcher initiates a 20 second velocity adjustment maneuver. Spacecraft separation usually takes place at T+25 minutes 38 seconds after launch.
The first launch from Xichang took place at 12:25 UTC on January 29, 1984, when the Chang Zheng-3 (Y-1) was launched the Shiyan Weixing (14670 1984-008A) communications satellite into orbit.
The Xichang 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 center 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 Xichang 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.
Quelle: NS
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Update: 13.04.2017
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China launches experimental Shijian-13 satellite via Long March 3B from Xichang
Launch took place in Sichuan Province just after 19:00 local time (11:04 UTC). Amateur footage showed the rocket lifting off but confirmation of launch success is likely to follow from state media in the next couple of hours.
The 4.6-tonne satellite is set to be positioned at 110.5E in geostationary orbit, from where it will provide Ka-band satellite broadband and multimedia services to mainland China and other areas with a capacity of more than 20 Gbps.
Shijian-13 will also carry out space-to-ground laser communications experiments, which could pave the way to much greater advances in satellite communications capacity.
The satellite has a design lifetime of 15 years and will mark the first full use of China's LIPS-200 xenon ion engines for propulsion.
Using ion engines instead of heavy conventional chemical fuels can allow a satellite to carry greater payloads or reduce launch costs.
The engines were developed by the Lanzhou Institute of Physics (LIP) and were first tested on Shijian-9A, launched in October 2012.
Following on-orbit testing, the Shijian-13 ('practice-13') satellite will be designated as Zhongxing-16 (Chinasat-16).
The satellite, based on the DFH-3B platform, was manufactured by the China Academy of Space Technology (CAST) and is planned for use in distance learning, medicine, internet access, airborne and maritime communications, and emergency communications.
Fourth for 2017, 246th Long March
Launch on Wednesday was China's fourth orbital mission of 2017, following TJS-2, a Kuaizhou-1A rocket launch, and Tiankun-1.
It was the 39th launch of the Long March 3B and its variants, which has only suffered one partial failure since its disastrous debut in February 2016.
The launch of Shijian-13 via Long March 3B was the 246th overall for the Long March rocket series.
The China Aerospace Science and Technology Corporation (CASC), the main contractor for the Chinese space programme and of which CAST is a subsidiary, is aiming for close to 30 launches in 2017, with further solid-fuelled rocket launches of small satellites also expected for another state-run space actor, CASIC.
China's busy April
Launch of Shijian-13 kicks off a very busy month for the Chinese space programme, which will see a major mission, a national space day and the revealing of a name and logo for the country's 2020 Mars mission.
The main business will be Tianzhou-1, the first test of cargo spacecraft that marks a crucial step towards constructing a space station.
Tianzhou-1 will launch from the new coastal Wenchang Satellite Launch Centre on the second Long March 7 carrier rocket, and, once in orbit, dock with Tiangong-2, with the main aim of testing and proving liquid propellant refuelling technologies in microgravity.
Tianzhou spacecraft, much like Russian Progress or American Cygnus resupply craft, will be required to keep the future Chinese Space Station (CSS) fuelled and its astronauts fully sustained and supplied.
Above: Tianzhou-1 undergoing testing at the AIT centre in North China (Framegrab/CGTN).
Preparations for launch are being finalised on Hainan Island, and the Yuanwang-7 tracking ship has started its maritime space monitoring and communication tasks ready for the mission, and the Long March 7 (Y2) launch vehicle has been vertically assembled.
Current rumours and projections suggest a launch for either April 20 or 23 and live streams of the launch will be available.
On April 24, the anniversary of the launch of the country’s first satellite (Dongfanghong-1) in 1970, China will host its second national ‘Space Day’, as part of space and science education outreach, and seeking to secure political rewards for the ruling Communist Party for major achievements.
The occasion will also be used to announce the winners of a public competition to both name and create a logo for China’s 2020 Mars mission, which includes an orbiter, lander and rover.
A competition to give a more attractive name to the Hard X-ray Modulation Telescope (HXMT), a space science mission which launches in June, will also close.
Above: The 8 finalist logos for the China Mars 2020 mission competition (CMEP).
Quelle: gbtimes