Non-Subscriber Extract
Fourth test flight of China’s Shen Zhou successful
- Article Tools
| 08 January 2003 |
By Phillip S Clark
The long-anticipated fourth flight of China’s Shen Zhou (SZ) spacecraft finally took place from 29 December to 5 January. It was launched from Jiuquan at 16.40 GMT using a CZ-2F vehicle and the 5 January landing occurred at 11.16 GMT.
Following the successful flight of SZ 3, which ended on 1 April 2002, China has regularly indicated that – barring major problems – it expects its first spacecrew to fly aboard SZ 5.
SZ 4 left its orbital module in orbit, where it will operate as an independent satellite for six or seven months, conducting Earth observation (perhaps military as well as civil), science and technical experiments.
Prior to the SZ 4 launch, members of China’s yuhang yuan (astronaut) training group worked inside the spacecraft and practised emergency exits while the vehicle was on the launch pad.
Although SZ 4 is said to be an improvement over SZ 3, it seems clear that both SZ 3 and SZ 4 are ‘Block 2’ spacecraft, essentially identical to the version that is likely to carry either two or three yuhang yuans into orbit before the end of 2003. SZ 1 in November 1999 was a very basic systems test, while SZ 2 was an improvement on its predecessor but still significantly different to SZ 3 and 4.
It seems likely that the SZ 3/SZ 4 mission is virtually identical to the one that will be seen when the first crew fly. This means that the SZ 5 mission will completely bypass the achievements of the Soviet Vostok and US Mercury programmes and will essentially match the US Gemini 5 mission in August 1965, which carried two astronauts in orbit for eight days – a duration record at that time. The Shen Zhou spacecraft can carry up to three yuhang yuans and is probably capable of at least a 21 ‘man-day’ mission (the original version of the Soviet Soyuz could fly for a maximum of 35 ‘man-days’ as a comparison).
US analyst Charles P Vick has studied commercial satellite imagery of the Jiuquan launch site. During 2002 he noted that the images showed the Chinese were working on a second launch pad. This will not only give the Chinese a back-up in case there is a launch pad accident but will also allow two Shen Zhou spacecraft to be readied for launches within days of each other. After two or three piloted Shen Zhou missions, the docking of two Shen Zhou spacecraft in orbit and a few weeks of joint flight as a small ‘interim’ laboratory is a reasonable expectation.
So when will we see Shen Zhou 5 with the first yuhang yuan crew? The Chinese have simply said that they expect the flight in the second half of 2003. Looking back, the Chinese have planned SZ missions about eight to nine months apart, which might suggest that China’s first space crew will fly in August-September 2003 – perfect timing for the mission to celebrate the October anniversary of China’s communist revolution.
495 of 1277 words