China on Sunday launched a new geostationary remote sensing satellite from the refurbished Zichhang Satellite Launch Center. A Long March-3B / G3 (Y3) – Chang Zheng-3B / G3 – The rocket orbited the G: 5Ofen-13 satellite, took off from the LC2 pad at 16:57 UTC.
The new satellite, possibly an improved version of the CAST, is being designated as a high-orbit optical remote sensing satellite used for orbiting G-Open-4, which was launched on December 28, 2015, mainly for land surveying, crop yield estimates, environmental management, and weather. Provide information services for national economic development, warning and forecasting, and comprehensive disaster prevention and mitigation.
However, some rumors suggest that the new bird may also be an optical reconnaissance satellite operating in geostationary orbit.
For this mission, the launch vehicle is associated with other elements such as rocket igniters and laser inertial group data, along with improvements associated with satellite ferring and cargo pressure transport systems.
This was the first launch in a few weeks from the Ziching Satellite Launch Center due to modernization work.
The Long March-3B (Chang Zheng-3B) launch vehicle was launched in 1986 to meet the demand of the international satellite launch market, especially the demand for high power and heavy communications satellites. Its development was based on Long March launch vehicle fight-proven technology.
Developed from the Chang Zheng-3A, the Chang Zheng-3B is the most powerful launch vehicle of the Chinese space launch fleet.
The CZ-3B has expanded launch propellant tanks, improved computer systems, a large payload fairing of 4..6-meters in diameter, and four strap-on boosters in the main phase that provide additional support during the first phase of the launch.
The rocket can launch an 11,200 kg satellite into low Earth orbit or a 5,100 kg cargo geographic transit orbit.
The CZ-3B / G2 (Advanced Version) launch vehicle was developed with the first core stage and strap-on boosters extended from the CZ-3B, increasing the capacity of the GTO to 5,500 kg.
On May 14, 2007, the first flight of the CZ-3B / G2 was successfully completed, sending NigcomSet-1 accurately into a pre-determined orbit. With a GTO launch capacity of 5,500 kg, the CZ-3B / G2 is dedicated to launching heavy GEO communications satellites.
The rocket structure also integrates all subsystems and consists of four strap-on boosters, first phase, second phase, third phase and payload ferring.
The first two phase and four strap-boo no boosters use hypergolic (N2O4 / UDMH) fuel, while the third phase 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.
In the first phase, the CZ-3B uses the YF-21C engine with a specific impulse of 2,961.6 kN thrust and 2,56.5 ns / kg. The diameter of the first stage is 35.3535 meters, and the length of the stage is 23.272 meters.
Each strap-boo booster YF-25 engine produces 740.4 kN. Equipped with thrust and a specific impulse of 2,456.2 ns / kg. The strap-on booster has a diameter of 2.25 m, and the length of the strap-on booster is 15,326 m.
The second phase is equipped with YF-24E (main engine – 742 kN / 2,922.57 ns / kg; four Vernier engines – 47.1 kN / 2,910.5 ns / kg). The diameter of the second stage is 3.35 meters, and the length of the stage is 12.920 meters.
The third phase is developing from the YF-75 engine that produces 167.17 kN and the specific impulse is 4,295 ns / kg. The fairing diameter of the CZ-3B is 4.00 m and its length is 9.56 m.
The CZ-3B can also use the new Yuanzeng-1 (“Expedition-1 ″) upper phase using a 6.5 kN engine burning UDMH / N2O4 with a specific impulse at 3,092 m / s. In the upper phase a lifetime of 6.5 hours, two burns can be managed and different orbits are achieved. This high phase was not used on this launch.
The typical flight sequence for the CZ-3B / G2 is to see the launch pitching 10 seconds after the lift after the flight from the Zichang Satellite Launch Center. 2 minutes and 7 seconds after the booster shutdown lift, one after the other from the first stage. The first stage of shutdown occurs at 1 minute 25 seconds in flight.
The split between the first and second phase occurs in 1 minute 26 seconds, followed by T + 3 minutes 35 seconds. Stage 2 The main engine shutdown takes 326 seconds in flight, then the Vernier engines shut down after 15 minutes.
The split between the second and third phase and the third phase ignition occurs one second after the second phase vernier engine shuts down. The first burn of the third phase will last 4 minutes and 44 seconds.
After finishing the first burn of the third phase, comes the coastal phase which ends at T + 20 minutes and 58 seconds, the third phase begins its second burn. This will have a duration of 179 seconds. After the second burn of the third phase, the projection begins a 20-second velocity adjustment exercise. The splitting of the spacecraft usually takes place at T + 25 minutes 38 seconds after launch. However, no confirmation has been given at this time.
The Zichang Satellite Launch Center is located in southwest China’s Sichuan Province, 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 southwest of the launch pad, providing flight and safety control during launch rehearsals and launches.
Other features at the ZichHang Satellite Launch Center include launch control centers, propellant fueling systems, communication systems for launch commands, telephone and data communications for users, and assistive devices for meteorological monitoring and forecasting.
