China successfully launches BDS M3-S satellite for its homegrown BeiDou navigation system

A Chinese Long March 3C carrier rocket has successfully lofted a new-generation satellite for the country’s indigenous BeiDou Navigation Satellite System. Designated BDS M3-S, the spacecraft was launched from the Xichang Satellite Launch Center in the southwestern province of Sichuan. Liftoff took place at 2:29 a.m. EST (7:29 GMT) on Monday, Feb. 1.
The rocket fired its core stage and two liquid-fueled strap-on boosters to start a short vertical ascent. Then, about 10 seconds into the flight, the launch vehicle began heading southeast, toward the Pacific Ocean. The boosters burned slightly over two minutes and were jettisoned. The separation of the first stage occurred shortly after and the rocket continued its flight for about two minutes until payload fairing was separated. Approximately six minutes after liftoff, the rocket’s second stage detached from the stack consisting of the third stage, the Yuanzheng-1 (YZ-1) upper stage and the satellite.
Immediately after second stage separation, the rocket’s third stage assumed control of the flight, firing its YF-75 liquid cryogenic engine. This phase of the mission lasted about 20 minutes, ending in separation of the YZ-1 upper stage. The spacecraft was deployed into a medium-Earth orbit (MEO) at an altitude of about 13,670 miles (22,000 km), inclined 55 degrees, approximately three-and-a-half hours later.

A Long March 3C carrier rocket carrying the 21st satellite for the BeiDou Navigation Satellite System lifts off from Xichang Satellite Launch Center, southwest China’s Sichuan Province, Feb. 1, 2016. Photo Credit: Xinhua/Xue Yubin
The mission didn’t get wide media coverage. Confirmation of the launch came from state-run media outlets several hours after liftoff.
BDS M3-S is the 21st satellite in the BeiDou series and the last spacecraft of the third phase of this system. It has a launch mass of 1.014 metric tons and its dimensions are 7.38 by 3.28 by 7.21 feet (2.25 by 1.0 by 2.2 meters). The satellite uses a new bus that features a phased array antenna for navigation signals and a laser retroreflector. It is also equipped with a chip, a technology demonstrator, that could help design smaller, better integrated, more reliable satellites in the future.
The satellite will join its four predecessors in testing inter-satellite crosslinks and a new navigation-signaling system that will set the framework and technical standards for global coverage. According to BeiDou project scientists, the latest satellite is crucial to integrating the two signal systems for regional and global navigation and switching between the two.
“Our new intersatellite crosslink system, featuring strong disturbance resistance and high-level privacy, is the core technology to compete with other countries’ navigation networks. The new satellite will fully verify our technology,” said Lin Baojun, the satellite’s chief designer.
BDS M3-S is expected to detect high energy particles, which abound in the orbit and threaten satellite components and functions so that the navigation system can better avoid their interference.
BeiDou is China’s global navigation satellite system that was started in 1994. It consists of two separate satellite constellations – a limited test system operating since 2000, and a full-scale global navigation system that is currently under construction. By developing the system, China aims to create an alternative to the American GPS and boost the country’s IT applications and hi-tech sectors. The system is planned to provide global coverage by 2020.
The 185 feet (56.3 meters) tall Long March 3C rocket that was used in Monday’s mission is a three-stage launch vehicle, designed to deliver up to 3.8 metric tons of payload into a geostationary transfer orbit (GTO) and up to 9.1 metric tons to low-Earth orbit (LEO). Its maiden launch was conducted on April 25, 2008.
For Monday’s flight, the rocket was in configuration with the YZ-1 upper stage. This stage was developed to deploy payload directly to high energy orbits like MEO.
BDS M3-S is China’s second mission of the year and the 224th flight of the Long March rocket series. The country opened 2016 with the launch of Belintersat-1 communications satellite for Belarus on Jan. 15 and started a very busy year in terms of sending payloads into orbit. In 2016, China intends to carry out more than 20 space missions.
The country also plans to return to the business of human space flight this year and conduct maiden launches of the next-generation Long March 5 and Long March 7 rockets. Shenzhou-11, a planned crewed mission, is slated to lift off from the Jiuquan Satellite Launch Center and dock with China’s second planned space station, Tiangong-2, which should be in orbit by the time the crew’s Shenzhou spacecraft is sent aloft. The exact launch dates for these missions have yet to be released.

Tomasz Nowakowski
Tomasz Nowakowski is the owner of Astro Watch, one of the premier astronomy and science-related blogs on the internet. Nowakowski reached out to SpaceFlight Insider in an effort to have the two space-related websites collaborate. Nowakowski's generous offer was gratefully received with the two organizations now working to better relay important developments as they pertain to space exploration.