China end 2012 with Long March 2D launch of Göktürk-2

by Rui C. Barbosa

China’s closing act on the orbital launch theatre for 2012 took place today at 04:12 UTC with the launching of the second Turkish made satellite, Göktürk-2, from the Jiuquan Satellite Launch Center. Göktürk-2 was carried into space by a Long March 2D (Chang Zheng-2D) launch vehicle.

China’s 19th Launch Of 2012:

Launch was schedule on December 19, but adverse weather conditions forecast at the launch site prompted a 24 hour advancement of the mission.

The Göktürk-2 Program is an Earth Observation Scientific Research and Technology Satellite Development Project that is the first National Earth Observation Satellite that has been funded by The Scientific and Technological Research Council of Turkey (TÜBİTAK) resources.

The contract for the development of the satellite was signed by the Ministry of Defence (MoD), The Scientific and Technological Research Council of Turkey (TÜBİTAK) and TUBİTAK UZAY-TAI Consortium on 13 April 2007, which became effective on 1st May, 2007.

With the Göktürk-2 Project, not only the Turkish national capabilities and resources for the space systems – such as new technologies, experienced manpower and possession of new infrastructures – will be developed, but the image requirements of the Turkish Armed Forces and other public institutions will also be met.

The development of the Göktürk-2 Project is an effort to develop a satellite system and a subsystem design and development capabilities, as well as to establish a bus platform for future remote-sensing missions.

The main payload consists of a multi-spectral imager (MSI). The spacecraft is specified for an operational life time of five years, in a sun-synchronous orbit at an altitude of approximately 700 km and a local time of descending node between 10:30 and 11:30 a.m.

The satellite will be capable of a 2.5 meter panchromatic resolution and a 10 meter multispectral resolution. Its mission will have a dual civil and military purpose, with applications on disasters management, emergency situations, environmental control, mapping and planning, landcover survey, geology, coastal zone vigilance, ecosystem monitoring, water resources, etc.

Launch mass of Göktürk-2 is 450 kg and the first images sent by the new satellite are expected to be received between December 25 and 30.

The solar panels and the pyro drive module have been developed by SpaceTech GmbH, Immenstaad – Germany. The solar generator system consists of three solar panels including the photovoltaic assembly, the solar panel deployment mechanisms, and the pyro drive module (PDM) electronics executing the deployment sequence of the mechanism.

Sat imageThe solar panel delivery included three flight models and three qualification model units. One of the QM panels has been equipped with active cells, the remaining two are mass dummies.

Each of the three panels on the spacecraft consists of four arrays each with three strings of 20 cells. In addition to the cells temperature sensors for thermal control, thermistors as input to the satellite’s maximum power point tracker as well as bleed resistors for controlled insulation with the spacecraft body are accommodated on each panel.

Third generation AZUR cells with a rated efficiency of 28 percent are used to make up the photovoltaic assembly. Each cell is protected with a by-pass diode and each solar string by a blocking diode. The qualification and flight models of the solar generator system have been delivered to Turkey in 2010 and 2011 respectively.

The PDM development including one mass dummy, one qualification model and one flight model has been performed with support from APCON.

The main task of the PDM is to provide regulated current for a predefined period to release the solar panel deployment mechanisms by activating thermal knifes. The electronics is implemented in cold redundancy (electronic part) and, via internal cross-coupling) allows access to both hot redundant power stages.

For safety reasons a three-level inhibit system is implemented. Also, the PDM operates in different modes that are directly related to the safety inhibits.

The PDM is characterized by a low mass and volume. The design can easily be adapted for a higher number of activation chains, different types of actuators, e.g. pyros, and a different communication interface to the on-board computer.

The Chang Zheng-2D launch vehicle is a two-stage rocket developed by the Shanghai Academy of Spaceflight Technology. With storable propellants is mainly used to launch a variety of low earth orbit satellites.

The development of CZ-2D was started in February 1990. From 2002, to meet the demand of SSO satellites, the payload fairing of 3350mm in diameter and attitude control engine for second stage have been successfully developed; and the discharge of remaining propellant and de-orbit of the second stage have been realized. This launcher is mainly used for launching LEO and SSO satellites.

Image of the launch from Turkish TVThe CZ-2D can launch a 1,300 kg cargo in a 645 km SSO. The rocket is 41.056m long and the first, second stages and payload fairing are all 3.35m in diameter.

Its first stage is the same of the CZ-4 Chang Zheng-4. The second stage is based on CZ-4 second stage with an improved equipment bay. Lift-off mass is 232,250 kg, total length 41,056 meters, diameter 3.35 meters and fairing length 6.983 meters. At launch it develops 2961.6kN engine thrust.

The first stage has a 27.910 meter length with a 3.35 meter diameter, consuming 183,200 kg of N2O4 / UDMH (launch mass of the first stage is 192,700 kg). Equipped with a YF-21C engine capable of a ground thrust of 2,961.6 kN and a ground specific impulse of 2,550 m/s. Burn time is 170 seconds.

The second stage has a 10.9 meter length with a 3.35 meter diameter, launch mass of 39,550 kg and consuming 45,550 kg of N2O4 / UDMH. Equipped with a YF-24C cluster engine with a main engine vacuum thrust of 742.04 kN and a vernier engine with a vacuum thrust of 47.1 kN (specific impulses of 2,942 m/s and 2,834 m/s, respectively).

The CZ-2D can use two types of fairings depending of the cargo. Type A fairing has a 2.90 meters diameter (total launch vehicle length is 37.728 meters) and Type B fairing with a diameter of 3.35 meters – total launch vehicle length is 41.056 meters.

The first launch of the CZ-2D was on August 9th, 1992 from the Jiuquan Satellite Launch Center orbiting the Fanhui Shei Weixing FSW-2-1 (22072 1992-051A) recoverable satellite.

This launch was the 174th Chinese successful orbital launch and the 174th launch of a Chang Zheng launch vehicle, also becoming the 56th orbital launch from the Jiuquan Satellite Launch Center, the fifth orbital launch from Jiuquan this year and the 19th Chinese orbital launch in 2012.

The Launch SiteThe Jiuquan Satellite Launch Center, in Ejin-Banner, a county in Alashan League of the Inner Mongolia Autonomous Region, was the first Chinese satellite launch center and is also known as the Shuang Cheng Tze launch center.

The site includes a Technical Centre, two Launch Complexes, Mission Command and Control Centre, Launch Control Centre, propellant fuelling systems, tracking and communication systems, gas supply systems, weather forecast systems, and logistic support systems.

Jiuquan was originally used to launch scientific and recoverable satellites into medium or low earth orbits at high inclinations. It is also the place from where all the Chinese manned missions are launched.

Presently, only the LC-43 launch complex, also known by South Launch Site (SLS) is in use. This launch complex is equipped with two launch pads: 921 and 603. Launch pad 921 is used for the manned program for the launch of the CZ-2F Chang Zheng-2F launch vehicle (Shenzhou and Tiangong).

The 603 launch pad is used for unmanned orbital launches by the CZ-2C Chang Zheng-2C, CZ-2D Chang Zheng-2D and CZ-4C Chang Zheng-2C launch vehicles.

The first orbital launch took place on April 24, 1970 when the CZ-1 Chang Zheng-1 (CZ1-1) rocket launched the first Chinese satellite, the Dongfanghong-1 (04382 1970-034A).

(Images via Turkish TV and

Related Articles