APSTAR-9 rides uphill on China’s Long March 3B

by Rui C. Barbosa

China has launched the APSTAR-9 communications satellite – on behalf of a Hong Kong-based satellite operator – on Friday. The launch was conducted by a Long March-3B/G2 rocket, launched from the Xichang Satellite Launch Center, with T-0 occurring on schedule at 16:16 UTC.

Chinese Launch:

The path to launch began on November 22, 2013 – when the China Great Wall Industry Corporation signed a satellite procurement $211.2 million contract with APT Satellite Company Limited of Hong Kong for the APSTAR-9 Satellite Program.

APSTAR-9 is a replacement satellite for APT Satellite’s APSTAR-9A satellite.

As one of the leading satellite operators in the Asia-Pacific region, APT Satellite Company Limited – since its operation commenced in 1992 – currently owns and operates five in-orbit satellites, namely APSTAR-5, APSTAR-6, APSTAR-7, APSTAR-7B (partial) and APSTAR-9A, covering regions in Asia, Europe, Africa, and Australia approximately 75 percent of the world’s population, all of which were supplied by the top American and European satellite manufacturers.

2015-10-15-232455The APSTAR 9 satellite is the first communication satellite based on DFH-4 platform procured by APT, which represents the breakthrough of delivering satellite to a leading international satellite operator by China space industry.

According to the contract, as the prime contractor, CGWIC was taked with the design, manufacture, assembly, launch, and deliver to the customer in orbit the APSTART 9 satellite and other ground control system necessary for the satellite operation, with the support of its subcontractors.

Based on DFH-4 platform, APSTAR-9 Satellite is developed by China Academy of Space Technology (CAST), subordinated to China Aerospace Science & Technology Corporation (CASC) with a designed service life of 15 years.

The satellite is equipped with 46 transponders which consist of 32 C-band transponders and 14 Ku-band transponders respectively. It will be located at geostationary orbit of 142 degrees east longitude.

2015-10-15-232600APSTAR-9 C-band transponders can provide quality satellite telecommunications and broadcasting services to customers across the Asia-Pacific region.

The Ku-band transponders are designed with the beams applicable to maritime and aircraft-board satellite broadband communication, the application of which for the surrounding seas of China and West Pacific has been optimized specifically.

C-band coverage consists of one broad beam for Asia Pacific region (“AP Beam”) and one enhanced beam for South East Asia (“SEA Beam”), suitable for video broadcast, VSAT networks and cellular backhaul services, Ku-band will cover West Pacific and East India Ocean region, providing DTH, VSAT, mobility services such as maritime and inflight connectivity.

China Satellite Launch & Tracking Control General (CLTC) was also responsible for the design and delivery of the ground segment for the operation of the satellite.

Since October 2014 APSTAR-9 satellite entered its assembly, integration and test (AIT) phase. The manufacturer CAST carried out AIT in its High Bay located in Beijing.

At the end of November the components for platform had all been installed and SPT1 (Satellite Performance Test) started, mainly verifying electrical interfaces between each on-board subsystems and ground testing equipment. In parallel, payload units were mounting on COMM panel. The End to End tests commenced in early 2015.

On May 15, 2015, TS Global Network (TSGN), a top Very Small Aperture Terminal (VSAT) connectivity provider in Malaysia, entered an agreement with APT Satellite Company Limited to invest in a designated payload on the APSTAR-9 satellite.

The payload, MySat-1, will provide C-band transponder capacity for the Association of South East Asian Nations (ASEAN) and Asia-Pacific markets.

2015-10-15-232657APSTAR-9 arrived at Qingshan Airport serving the Xichang Satellte Launch Center, on August 27, entering into the launch campaign phase.

At the end of September, APT Satellite, Sinosat(HK) and Shenzhen Marinesat signed an APSTAR-9 pre-launch sales contract. Leveraging APSTAR-9’s ocean coverage, this three-party cooperation is expected to create vertical synergy within the service scopes of the three companies.

DFH-4 is the third generation communications satellite bus in China with high power, strong payload capacity and extended service life. It consists of propulsion module, service modules and solar arrays.

Its dimensions are 2360mm×2100mm×3600mm, with a liftoff mass of 5,200 kg. Solar Array Power is 10.5 kW (EOL) and payload power is 8 kW.

The platform can be equipped with C, Ku, Ka and L transponders. It uses a 3-axis stabilization mode and its station keeping precision is west/east ±0.05° and north/south ±0.05°. Antenna Pointing Precision is less than 0.1° and it is expected to have a service lifetime in orbit of 15 years.

Launch vehicle and launch site:

Developed from the Chang Zheng-3A, the Chang Zheng-3B is the most powerful launch vehicle on the Chinese space launch fleet.

2015-09-12-163133The 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, 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.

2015-09-12-163210The 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.

2015-09-12-164401The 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 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 was not used on this launch.

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.

2015-07-25-130117Equipped 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 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.

The first launch from Xichang took place at 12:25UTC on January 29, 1984, when the Chang Zheng-3 (Y-1) was launched the Shiyan Weixing (14670 1984-008A) communications satellite into orbit.

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