. SHENZHOU 7

Flight Crew

ZHAI, Zhigang, 42, PLA Air Force, commander

LIU, Boming, 42, PLA Air Force, orbital module monitor

JING, Haipeng, 42, PLA Air Force, descent module monitor

Flight log

On September 27, 2008, Zhai Zhigang became the first Chinese taikonaut to perform an EVA. This historic event, 43 years after the first EVAs had been per­formed, meant that China had become the third nation, after the Soviet Union (Russia) and the U. S.A., to achieve EVA capability. The buildup to China’s third manned space flight had for some time indicated that a short EVA was part of the program, and that it would be a further step towards the creation of a small space station.

The flight into Earth orbit lasted approximately 583 seconds. In the central couch flew mission commander Zhai Zhigang, with Liu Boming to his right and Jing Haipeng to his left. They would occupy the same positions for landing. Five hours into the mission, the onboard engines were used to refine the orbit, allowing for a flight time of up to five days. The duration of this mission had previously been announced at only three days, to prevent Western speculation of an unplanned early return.

This was the first Chinese mission to fly three crew members, with a further three as backup—Chen Quan (commander), Fei Junlong (OM monitor), and Nei Haisheng (DM monitor)—making a training group of six. The prime crew for the flight had been announced on September 17 and of the backup crew only Chen Quan had not flown in space. The other two were the crew of Shenzhou 6, lending experience to preparations for this technically challenging mission.

A display model of the Chinese Feitian (“Flying Sky”) EVA suit of the type used on Shenzhou 7. Photo copyright: MarkWade/Astronautix. com, used with permission.

The space walk was planned to last no more than 30 minutes, although the crew’s EVA preparations took about 15 hours. This was mainly taken up with assembling the suit, putting it on, and then checking it out for use outside the orbital module. It was reported that there were 30 contingency plans developed for the EVA to ensure the safety of the crew and the integrity of both the suit and spacecraft during the operation. It was also revealed that a fire alarm at the Mission Control Center shortly before the start of the EVA was in fact a false alarm, presumably adding to the tension at the time.

The EVA actually lasted 22 minutes and was conducted by Zhai Zhigang, wearing the Chinese-developed Feitian space pressure suit which is similar to the Russian Orlan (“Bald Eagle”) EVA suit used since 1977 for Russian space station – based EVAs. Supporting his commander from inside the depressurized Orbital Module of Shenzhou 7, Liu Boming wore a Russian Orlan M suit (No. 42) for comparison with the national suit. The name Feitian comes from the Mandarin fei (flying) and tian (sky).

Zhai Zhigang’s exit from the module was hindered slightly by difficulties in opening the hatch. Once these were resolved and in full view of the exterior TV camera, Zhai Zhigang floated head first outside the module, and then used hand­rails mounted outside the module to perform a wandering excursion to retrieve experiment samples and wave a Chinese flag for the benefit of the camera. The experiment was a solid lubricant exposure device, about the size of a book. It was installed on the outer wall of the Orbital Module during launch preparation and retrieved during the EVA after about 40 h exposure to the space environment. The aim of the experiment was to study the characteristics of lubricants designed for future space-based “moving components in space facilities”.

Limited during the EVA by restraint cables, the taikonaut remained close to the EVA hatch, his movements captured by two cameras providing spectacular panoramic images of the historic event. Conducting a short (approximately 4 min) stand-up EVA, Liu Boming handed his commander a national flag. Though ready to assist if necessary, he did not fully exit the module. The third crew member, Jing Haipeng, remained inside the Descent Module monitoring the EVA and the general condition of the spacecraft.

Though EVAs of up to 7 hours are reportedly possible in the Feitian suit, this initial excursion was limited to just over 20 minutes to evaluate the design and procedures, providing baseline data in order to plan longer excursions on future missions. No serious difficulties were reported, although it was clear that at one point the spacewalker became entangled in his tether. At the end of the EVA period, both men returned to the Orbital Module of the spacecraft, sealed the hatch and repressurized the module before opening the internal hatch and rejoin­ing their colleague. Apart from the gloves, the suit units were not returned to Earth as there was not enough room inside the Descent Module to stow them. The success of the first Chinese space walk was feted across the world as a major milestone in the development of Chinese manned space flight. The total hatch open time was 22 minutes, with Zhai Zhigang actually outside for only 10 minutes, with about 4 minutes taken for exit and entry into the module.

Two hours after the end of the EVA, a small, 40 cm long, 40 kg monitoring satellite called “BanXing” was deployed from the nose of the Shenzhou 7 Orbital Module. It carried a liquid ammonia “boost device” maneuvering engine and a pair of 150-megapixel stereo cameras. Its objectives were to evaluate minisatellite technology, to observe and monitor the Shenzhou spacecraft and to test the track­ing and approach technology being developed for space rendezvous and docking. After taking video and still images of the spacecraft, the satellite was maneuvered to approximately 100-200 km away. Following the return of the crew to Earth, the small satellite re-rendezvoused with the abandoned Shenzhou 7 Service Module and then orbited around it, imaging the module. The operational lifetime of the minisatellite was reportedly three months. It finally reentered on October 29, 2009, about 13 months after its deployment from Shenzhou 7.

As a further development in support technologies for improved coverage of manned missions the Chinese had launched their first data relay satellite Tianlian 1 (“Skylink 1”) on a Long March 3C carrier rocket from the Xichang Satellite

Launch Center on April 25, 2008. The relay satellite was used to improve orbital communications with Shenzhou to approximately 60%. Ground stations and ocean tracking ships can only cover about 12% of each orbit, so the data relay satellite improved this by covering 50% of the orbit. Two new tracking ships, Yuanewang 5 and 6, were also commissioned in time to support the Shenzhou 7 mission.

The Chinese reported that 220 technical modifications had been implemented to the Shenzhou 7 mission after the flight of Shenzhou 6. Most notable were the removal of the solar panels on the Orbital Module to allow for the EVA, the installation of EVA handrails, and an additional camera installed to support the space walk. The removal of the solar arrays meant that the OM would not remain in space as on earlier missions, but would reenter after its separation at the end of the mission. There were also more than 30 other upgrades and improvements to the carrier rocket since the last mission, notably to the pipes inside the second stage.

Life on board the spacecraft was also improved for the crew, with a custom – made compact and storable toilet to allow collected urine to be recycled for drinking water. There were 80 food varieties available to them, compared with the 50 available for Shenzhou 6. The choices included spicy kung-pao chicken, de-shelled shrimp, and a selection of dry fruits.

On September 27, Shenzhou 7 reportedly passed within 45 km of the International Space Station and, although no statements were released by Chinese authorities, the American media reported that China had deployed its companion satellite BX-1 only four hours earlier. They suggested that it was a dual military – civilian mission, speculating that it may have been a test of orbital antisatellite inception technology and space station observation.

On September 28, with the primary objective of the mission completed, the de-orbit and entry maneuvers were followed by a landing in Siziwang Banner in central Inner Mongolia, between Hohhot and Erenhot. The success of this mission led to some speculation that the next Shenzhou missions would include docking with a rudimentary space laboratory.

Milestones

261st manned space flight

3rd manned Chinese spaceflight

1 st Chinese three-person space flight

3rd manned Shenzhou flight

1 st three-person Shenzhou flight

1st Chinese EVA

1st Chinese stand-up EVA