The CZ-6 Chang Zheng-6 is a liquid-propellant, small-load space launch vehicle developed by Shanghai Academy of Spaceflight Technology (SAST).

The launch vehicle is based on the 3.35m-diameter boosters, which have been developed as a strap-on booster for the CZ-5 family of SLV.The core stage consists of a single 120t-thrust YF-100 engine that burns oxygen and kerosene (LOX/Kerosene) propellant, which causes less pollution compared to the UDMH/N2O4 (nitrogen tetroxide) propellant currently in use.

The Long March-6 is designed for small-load launch missions, with a sun-synchronous orbit (700km SSO) capability of 1,080 kg.

In September 2009, the Chang Zheng-6 launch vehicle development program was officially approved by the Chinese Government and the first flight was expected to take place in 2013. SAST was tasked with the development of the new launch vehicle in July 2008.Overall length is 29.237 m with a total mass at liftoff of 103,217 kg. Dry mass of the three stages combined is 9,020 kg. Fairing diameter is 2.25 m / 2.6 m, and the vehicle is capable of launching a payload of 1,080 kg to a 700 km SSO orbit (500 kg if only Chinese tracking stations are used).

The first stage has a 3.35 meter diameter and is equipped with a single YF-100 engine, consuming 76,000 kg of kerosene RP-1/LOX. The YF-100 engine is capable of a ground thrust of 1,177 kN and a ground specific impulse of 2.9 km/s. Burn time is 155 seconds. The first stage uses four 1000 N thrusters for roll control.

The second stage has 2.25 meter diameter and consumes 15,150 kg of kerosene RP-1/LOX. It is equipped with a YF-115 developing 147.1 kN (sea level) or 176.5 kN (vacuum), with a vacuum specific impulse of 3.35 km/s. The second stage uses four 25 N thrusters for roll control.The third stage is equipped with four engines with 4 kN (each), along with eight 100 N thrusters for attitude control. The engines are powered by a mixture of kerosene and hydrogen peroxide.
The Long March-6 first cargo:

Twenty small Chinese satellites are the cargo of the Long March-6 first mission.

The ZDPS-2 Zheda Pixing-2 satellites is a dual satellite platform mission designed by Zhejiang University to provide a technology demonstration of guidance, navigation and control (GNC) strategies for spacecraft formation flying.ZDPS-2 is the latest Nano-satellite mission of Microsat Research Center, Zhejiang University. It constitutes an in-orbit test platform for formation flying technology with two identical nano-satellites, ZDPS-2A and ZDPS-2B.

The main objectives of ZDPS-2 mission are to demonstrate advanced guidance, navigation and control algorithms for formation flying; in-orbit performance test of self-designed ammonia micro-propulsion system; validate the precision of the S-Band Inter-Satellite Pseudo-Noise (PN) code ranging system; to validate the dual-frequency GPS receiver and the relative orbit determination algorithm; and to validate the MEMS accelerometer in-orbit calibration algorithm.

The main subsystems and components of the ZDPS-2 gained space heritage on the ZDPS-1A mission launched on September 22, 2010. Both ZDPS-2A and ZDPS-2B are 25 × 25 × 25 cm cube-shaped and weigh around 12 kg.

The satellites are equipped with tri-junction Ga-As solar cells as the primary power, tiled on all six planes of the satellite body, which have a 26.8% theoretical efficiency, and a Li-ion battery pack of ten cells from Sanyo serves as the secondary power. The transceiver works under the Universal S-Band (USB) TTC system, enjoys uplink data rates of 2kbps and adjustable downlink data rates of 1kbps-64kbps.The on-board computer (OBC) is composed of multi-CPU with FPGA, providing a universal computing, storage, management platform for command execution, TT&C, attitude & orbit control, payloads, etc.

Sub-degree level attitude measurement will be achieved through a 3-axis magnetometer, a 3-axis MEMS gyroscope, four-quadrant analog sun sensors mounted on six surfaces and a digital sun sensor.

Attitude control utilizes a momentum wheel, installed on the pitch axis, to provide both momentum bias and reaction actuation for pitch attitude maneuver, and three orthogonally mounted magnetic coils provide active control torque for detumbling and three-axis stabilization, with pointing accuracy of better than 2° and steady precision 0.1°/s.


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