China began the preparation for a full-range flight test of its Dongfeng 5 (CSS-4) intercontinental ballistic missile (ICBM) in the late 1960s. A fleet of ocean-going vessels were required to track and recover the missile re-entry vehicles in their impact zone in the Southern Pacific. Construction of various support vessels for the programme began in July
1967 under the code name Project 718. The construction programme included two missile range instrumentation ships (Yuanwang 1 and 2), an ocean scientific survey ship (Xiangyanghong 10), and an ocean rescue ship (Dajiang class), all of which were built at the Jiangnan Shipyard in ShanghaiYuanwang 1 was launched on 31 August 1977, followed by Yuanwang 2 on 1 September 1978. The vessels were 191m in length, 20.6m in beam, and 9m in draft. They had a full displacement of 21,000 tonnes, and were powered by steam turbines which produced 16,000hp propulsion. The vessels could travel at a maximum speed of 18 knots. The ships were fitted with C- and S-band mono-pulse tracking radar, Cinetheodolite laser ranging and tracking system, velocimetry system, and onboard computers to track and communicate with the spacecraft. They use a combination of inertial, satellite, and stellar for accurate navigation and positioning. Communications include HF, ULF, UHF, and SATCOM, in the form of secured telephone, radio, fax, and data link. The ships are also equipped with a range of weather forecasting equipments including weather radar, weather balloons, and meteorological satellite image receiving terminals.In March 1980, the two vessels joined a naval task force of over 20 vessels deployed to the Southern Pacific. On 18 May 1980, a Dongfeng 5 ICBM was launched from the Jiuquan (Shuang Cheng Tzu) Missile and Space Centre. After flying for 29 minutes and 57 seconds over a distance of 9,070km, the missile's re-entry vehicle hit its targeted impact zone in the Southern Pacific, where it was successfully recovered by the task force.
1967 under the code name Project 718. The construction programme included two missile range instrumentation ships (Yuanwang 1 and 2), an ocean scientific survey ship (Xiangyanghong 10), and an ocean rescue ship (Dajiang class), all of which were built at the Jiangnan Shipyard in ShanghaiYuanwang 1 was launched on 31 August 1977, followed by Yuanwang 2 on 1 September 1978. The vessels were 191m in length, 20.6m in beam, and 9m in draft. They had a full displacement of 21,000 tonnes, and were powered by steam turbines which produced 16,000hp propulsion. The vessels could travel at a maximum speed of 18 knots. The ships were fitted with C- and S-band mono-pulse tracking radar, Cinetheodolite laser ranging and tracking system, velocimetry system, and onboard computers to track and communicate with the spacecraft. They use a combination of inertial, satellite, and stellar for accurate navigation and positioning. Communications include HF, ULF, UHF, and SATCOM, in the form of secured telephone, radio, fax, and data link. The ships are also equipped with a range of weather forecasting equipments including weather radar, weather balloons, and meteorological satellite image receiving terminals.In March 1980, the two vessels joined a naval task force of over 20 vessels deployed to the Southern Pacific. On 18 May 1980, a Dongfeng 5 ICBM was launched from the Jiuquan (Shuang Cheng Tzu) Missile and Space Centre. After flying for 29 minutes and 57 seconds over a distance of 9,070km, the missile's re-entry vehicle hit its targeted impact zone in the Southern Pacific, where it was successfully recovered by the task force.
In the mid-1980s, Yuanwang 1 and 2 also supported the full-range test flight of the Julang 1 (CSS-N-3) submarine-launched ballistic missile (SLBM) and the launch of China’s first geostationary communications satellite Dongfanghong 2. In 1986, the two vessels received their first modernisation refit to support China’s commercial satellite launches for international customers. In the late 1990s, they received their second major refit to support the Project 921 human spaceflight programme.
During Shenzhou flight missions, Yuanwang 1 was normally positioned in the Sea of Japan to monitor the separation of the spacecraft with the launch vehicle, and to command the deployment of the spacecraft’s solar panels. Yuanwang 2 was normally positioned in the Southern Pacific to monitor the insertion of the spacecraft into its initial parking orbit. By 2005, Yuanwang 1 had undertaken 41 voyages for 38 missile and spacecraft launches, totalling some 1,500 days of operation in the sea and having travelled a total distance of 270,000 nautical miles. Yuanwang 2 had travelled a total distance of 400,000 nautical miles in 31 voyages. The two vessels were retired from active duty after the Shenzhou 7 mission in 2008.
Yuanwang 3
Yuanwang 3 was commissioned in the mid-1990s in response to the demands of China’s expanding space programme. The ship was equipped with more advanced tracking and communications systems including an S-band high-accuracy tracking radar. During the Shenzhou missions, the vessel was normally positioned in the South Atlantic, off the African coast, responsible for initiating the spacecraft’s retrofire and re-entry. By 2005, the ship had travelled a total distance 214,000 nautical miles in 18 missions.
Yuanwang 3 was 180m in length, 22.2m in beam, and 8m in draft. The vessel has a full displacement of 16,792 tonnes, and is powered by diesel engines, which give a maximum speed of 20 knots. The vessel has a maximum range of 18,000 nautical miles and is fitted with a helicopter deck at its stern, though with no helicopter hanger.
Yuanwang 4
Yuanwang 4 was originally built in the late 1970s, also under Project 718, as a multi-functional survey ship named Xiangyanghong10 to support the recovery of the missile’s re-entry vehicle. Its roles included oceanographic survey, weather forecasting, gravity and magnetic survey, long-range communication relay, and underwater acoustical data collection. It also served as a mother ship for the Sa 321 Frelon helicopters and a deep-ocean underwater vehicle. The vessel was operated by the State Oceanic Administration (SOA) before its conversion.
In 1998, Xiangyanghong10 was converted into a space tracking ship to supplement the existing three Yuanwang tracking ships in supporting the human spaceflight programme. The vessel’s iconic large crane and communication mast on its bow deck were removed and replaced by a tracking radar dish. The vessel was 156.2m in length and 20.6m in beam, and had a full displacement of 13,000 tonnes.
Unlike previous Yuanwang tracking ships, Yuanwang 4 lacked the ability to control the spacecraft, and merely served for tracking and communications relay roles. During the Shenzhou missions, Yuanwang 4 was normally positioned in the Southern Pacific to relay the video and audio communications between the Shenzhou spacecraft and the mission control centre in Beijing. By 2005, Yuanwang 4 had supported 9 space launches and travelled a total distance of 120,000 nautical miles.
Yuanwang 4 was seriously damaged in a collusion and fire accident in mid-2007, and was subsequently withdrawn from service.
Yuanwang 5 and 6
The Shanghai-based Jiangnan Shipyard began to construct two hulls of the third-generation Yuanwang class space tracking ship in 2005. The first hull Yuanwang 5 was launched on 15 September 2006, with the sea trial beginning in early 2007. The ship was officially commissioned on 29 September 2007. Its sister ship Yuanwang 6 was commissioned on 12 April 2008.
The two new Yuanwangs were 222.2m in length and 25.2m in beam, and had a full displacement of 25,000 tonnes. Their onboard equipment include unified S-band (USB) tacking and communications radar, C-band tracking radar, satellite communication antennas, Cinetheodolite laser ranging and tracking system, Doppler weather radar, and meteorological satellite image receiving terminals. The vessels also feature a fibre optics-based shipboard network for data sharing and exchange between different sub-systems onboard, and are capable of real-time voice/image communication and data exchange with the land-based control centre. Yuanwang 6 is largely identical to Yuanwang 5, but features a large mission control centre that occupied two decks.
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