24/7 Space News  





. Shenzhou-2 Returns While Orbital Experiments Continue

An undated photo shows a yuhangyuan entering the hypobaric chamber at the Chinese Yuhangyuan Training Base in Space City, which is located at the western suburb of Beijing.
by Wei Long
Beijing - Jan. 19, 2001
China took a significant step towards manned spaceflight after Shenzhou-2 (SZ-2) completed its mission and landed successfully in Inner Mongolia Tuesday (Jan. 16) evening, Xinhua News Agency announced.

After completing 108 orbits the manned spacecraft, which flew unmanned in the second test flight, touched down at the predetermined landing site at 7:22 p.m. Beijing Time (Jan. 16 11:22 UTC). Based on the announced landing time, mission duration is 6 days 18 hours 22 minutes. People's Liberation Army Daily said that SZ-2 travelled 5.4 million km in the voyage.

The Hong Kong-based Wen Wei Po newspaper suggested yesterday (Jan. 17) that the first manned mission may not be far off in the future. The newspaper reported that four yuhangyuans ("astronauts") were undergoing intense training at the training base here.

Presumably the first manned mission would have a two-person crew with the other two yuhangyuans as the backup crew. However, a four-person crew for the first manned mission is also possible. Early last November Beijing Youth Daily and other Chinese media outlets reported that Shenzhou would be capable of accommodating four yuhangyuans.

Wen Wei Po also wrote that Party leaders repeatedly emphasized that safety of yuhangyuans would be of paramount importance and must be guaranteed before they would be sent into space.

SZ-2 lifted off from the Jiuquan Satellite Launch Centre (JSLC) in the northwestern Gansu Province aboard a Changzheng-2F (Long March-2F) rocket, which made its second flight, on Jan. 10 at 1:00:03.561 a.m. Beijing Time (Jan. 9 17:00:03.561 UTC).

During the mission SZ-2 executed multiple manoeuvres to change and maintain its orbits and attitude.

The first significant orbit manoeuvrer occurred on the 14th orbit, which was 20 hours after launch, at 9 p.m. Beijing Time (Jan. 10 13:00 UTC). Beijing Aerospace Command and Control Centre (BACCC), the lead control centre which is located at the foot of Yanshan ("Swallow Mountain") in the NE suburb of the capital, issued a command to SZ-2 to circularize its orbit from the initial elliptical path. This raised the low point of the orbit from about 200 km to 340 km.

Xi'an Satellite Control Centre (XSCC) in the central Shaanxi Province and the fleet of four Yuanwang (YW, Yuanwang means "Long View") tracking vessels at sea provided continuous tracking and control support to BACCC.

On this flight YW-1 was at Bo Hai off the NE coast of China and YW-2 stationed in the Pacific Ocean. YW-3 took the longest voyage navigating through the Pacific and Indian Oceans to reach its designated position in the south Atlantic Ocean. YW-4 took up position in the Indian Ocean and encountered rough sea with swell of over 10 metres high.

SZ-2 remained in the circular orbit for 31 circuits before another major orbit manoeuvrer was needed. On Jan. 12 which was Flight Day 3 at 8:24 p.m. Beijing Time (12:24 UTC), XSCC commanded SZ-2 to fired its engines to maintain orbit for the first time in the mission.

Three days later on the 15th (Flight Day 6), SZ-2's maneuvering engines fired again for another orbit maintenance.

On Flight Day 7 (Jan. 16) mission controllers were ready to retrieve the Descent Module. During orbit 107 when SZ-2 approached the south Atlantic Ocean, YW-3 tracking ship had the important task of preparing and sending commands to the spacecraft to begin deorbit operation.

At 6:33 p.m. Beijing Time (10:33 UTC) mission controllers on board YW-3 directed SZ-2 to start deorbiting.

Over the speaker system a series of verbal commands and confirmation reports were broadcast: "Changjiang No. 3 first attitude correction begin!", "First attitude correction completed!", "Orbital and Descent Modules separation!", "Separation successful!", "Second attitude correction completed!", "Engine fired!", "Engine stopped!".

(All four Yuanwang tracking ships used the codename Changjiang ("Yangtze River") followed by their ship number during audio transmission. Thus "Changjiang No. 3 first attitude correction begin!" means that Yuanwang-3 starts transmission of the first attitude correction command.)

On the other side of the globe in Inner Mongolia, darkness just fell at the landing site at the steppe. The recovery team, with four helicopters which were already airborne and six recovery vehicles in position, waited for the arrival of the Descent Module in the bitterly cold minus 30 deg Celsius weather.

Suddenly a fireball flashed in the sky. Someone yelled that SZ-2 appeared.

Then the speaker system broadcast the words "Attention all units, spacecraft enters blackout zone!", a signal that the Descent Module encountered denser part of the atmosphere during its reentry. Plasma buildup around the spacecraft completely blocked out communications. Silence took over the landing site at this time.

Finally radar tracking station No. 1 spotted the falling module. Ground crews broke out a brief cheers.

When SZ-2 dropped to 30 km above ground, controllers issued the command to activate the power source on board the spacecraft to open the descent parachute. Immediately a drogue chute came out which then extended the 1,200-square-metres descent parachute wide open.

At 1.5 metre above ground, retrorockets on SZ-2 fired to brake the descent. The bright flare lit up the dark steppe. SZ-2 made a successful touchdown! A People's Liberation Army (PLA) commander immediately ordered the four helicopters to fly towards the touchdown site.

President Jiang Zemin telephoned the Chief Commander of the manned spaceflight project Cao Gangchuan to congratulate the entire project team.

Carried aboard SZ-2 were 64 science instruments and live biological specimens, including six mice, fruit flies and small aquatic and terrestrial organisms, for various experiments.

More than 50 science institutions and universities participated in the collection of experiments, which covered the disciplines of materials, life sciences, astrophysics, space environment physics, and other microgravity sciences.

BACCC said that all instruments worked without any problems and maintained stable qualities. The Descent Module will be returned to Beijing within the next few days so scientists can retrieve their experiments for analysis.

One experiment that did not belong to the group of science investigation was the audiovisual communications experiment. Video footage of the interior of the Descent Module, music and a taped audiovisual introduction of the Chinese manned spaceflight project were beamed back to Earth with great clarity.

The Beijing control centre also confirmed that the set of astrophysics and space environment experiments in the Orbital Module would remain in orbit to conduct further observations for another six months. BACCC said that power supply, attitude control and data management systems on the Orbital Module were functioning nominally.

After 8 days 4 hours in space, SZ-2 Orbital Module was in an orbit of 388.2 x 404.4 km inclined at 42.6 deg and a period of 92.5 minutes. The present orbit has been raised since the module separated from the Descent Module. The previous average altitude of the Orbital Module was 337.8 km. The higher altitude prolongs the orbital life of the module.

Meanwhile the 136 members of the Shenzhou project testing team from the Shanghai Academy of Spaceflight Technology (SAST) returned home on Tuesday (Jan. 16). The team left for JSLC on Oct. 23 last year.

Shanghai Mayor Xu Kuangdi sent the team a congratulatory message. SAST also received $200,000 renminbi ($24,200 U.S.) from the Shanghai Aerospace Machinery and Electronics Corporation as development fund.

SAST is a key research institute of the Shenzhou spacecraft project. Its primary responsibility is designing and developing the Propulsion Module, propulsion system, electrical system and part of the command and communications system.

SAST said that the propulsion system performed flawlessly in this mission.

Jin Zhuanglong, Director of SAST, mentioned that SZ-2 was installed with the complete flight-rated system according to manned spaceflight requirements. Two key systems, environment control and life protection, and emergency life support, were installed on SZ-2 but not on the Shenzhou maiden flight.

Xinhua said that the successful SZ-2 flight showed a steady sign of the manned spaceflight project towards maturity. The multidisciplinary science experimentation on the mission opened a new era of space science research and space resource exploitation, which would foster development of science and technology and national economy.

Related Links
SpaceDaily
Search SpaceDaily
Subscribe To SpaceDaily Express

Did Shenzhou-2 Go Splat
Hong Kong - Jan. 19, 2001
In the three days since Shenzhou-2 returned to Earth, China has released not a single photo of the capsule. This is in stark contrast to the first Shenzhou mission in late 1999 when China released a whole series of photos of the spacecraft after it landed in central China.
.
Get Our Free Newsletters Via Email