China plans to attempt a remotely controlled docking in November between its new Tiangong-1 space lab and the unpiloted Shenzhou-8 crew vehicle, followed by two manned missions to the miniature space station next year.
The practice missions will set the stage for the eventual launch and
utilization of a three-module, 60-ton Chinese space station “around 2020,” according to Zhang Hailian of the China Manned Space Engineering Office (CMSEO). Zhang reported on the Sept. 29 Tiangong-1 mission in a much-anticipated session here at the 62nd International Astronautical Congress.The 8.5-ton spacecraft, consisting of a pressurized experiment module and a “resource module” with power, attitude control and propulsion systems, launched on a Long March 2F rocket after a one-month delay while engineers analyzed the Aug. 18 failure of a Long March 2C, which has elements in common with the 2F.
The launch was cleared after the mishap was traced to a failure in a vernier engine thrust-vector actuator, Zhang says. Tiangong-1 was launched into a 350-450-km initial orbit inclined at 42 deg., which was later circularized at 350 km (220 mi.).
Three weeks before the Shenzhou-8 launch next month, the space lab will be lowered to a rendezvous altitude of 344 km. The rendezvous and docking will be controlled from the ground, following a period of autonomous flight to the rendezvous.
During docked operations Tiangong-1 will be the active spacecraft, maintaining attitude control for the stack while Shenzhou-8 goes into “berthing mode,” according to Zhang. Once the Shenzhou undocks for re-entry, Tiangong-1 will boost itself up to a 370-km orbit and go into “long-term operating managing mode,” he says.
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