Long March 3B launches APStar-6C communications satellite
On Thursday, May 3 China launched its flagship Long March 3B rocket on a mission to send the APStar-6C communications satellite to orbit.
The booster thundered off the launch pad at 16:06 GMT (12:06 p.m. EDT) from Launch Complex 2 at the Xichang Satellite Launch Center (XSLC) located in China’s Sichuan Province.
The mission was initially scheduled to lift off on March 9, 2018, however it was postponed to April 21 and then slipped to May 6. However, Beijing decided to conduct the launch three days earlier, not disclosing what was behind this move and previous delays.
Although China has not disclosed any information about Thursday’s flight, it is assumed that the launch vehicle’s ride to space lasted approximately half an hour. The flight portion of the mission ended with the deployment of the payload into a geosynchronous orbit.
The launch of APStar-6C occurred about a year and a half after the satellite had passed its Critical Design Review (CDR) in October of 2016. In August 2017, the engineers completed mating of the spacecraft’s service, propulsion and communication modules. One month later the satellite was fully assembled and was ready for its shipment to Xichang, what finally took place on March 9, 2018.
APStar-6C is a commercial communication satellite based on the DFH-4 platform, provided by China Aerospace Science and Technology Corporation (CASC), which represents the breakthrough of delivering satellites to a leading international satellite operator by China space industry. The DFH-4 bus is described by China as having high-power output, a strong payload capacity and an extended service life.
APStar-6C is equipped with 45 C-, Ku-, and Ka-band transponders which are designed to provide high power services to customers across the Asia-Pacific region, for VSAT (very-small-aperture terminal), video distribution, DTH (direct-to-home), cellular backhaul and mobility broadband applications. The spacecraft is fitted with two deployable solar arrays and is designed to be operational for 15 years.
The satellite will be operated by Hong Kong-based APT Satellite Company Limited. It was launched to replace the APStar-6 spacecraft launched in April of 2005.
The three-stage Long March 3B rocket used for Thursday’s flight is currently the most powerful Chinese launch vehicle in service. The 180-foot (55-meter) tall booster, developed by CASC, is capable of sending up to 12 metric tons of payload into low-Earth orbit or 5 metric tons of cargo into geostationary transfer orbit (GTO).
The 3B/E version that was employed for this mission, is an enhanced variant of the rocket, featuring an enlarged first stage and boosters. This iteration of the rocket was introduced in 2007 to increase the vehicle’s GTO cargo capacity and lift heavier geosynchronous equatorial orbit (GEO) communications satellites.
Thursday’s lift off was the 274th that was carried out by the Long March rocket series. It was also China’s 14th flight so far this year. Beijing’s next planned launch is currently set to take place on May 21 when a Long March 4C booster will blast off with the Chang’e 4 lunar mission and two DSLWP satellites, designated DSLWP-A1 and A2.
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