China’s first crewed spacecraft, developed for the human spaceflight programme to fulfil the missions of achieving crewed orbital flight, developing EVA and rendezvous docking techniques, and transporting crews to and from the space station. The spacecraft was modelled after the Russian Soyuz-TM but slightly larger in size and has been developed from Chinese technology. First unmanned test flight took place in 1999 and the first manned mission in 2003. The Shenzhou spacecraft is expected to remain in service into the 2020s as the crew transportation vehicle for China’s manned space station.
Type: Crewed capsule vehicle. Crew size: 3. Programme: Project 921-I, Project 921-II, Project 921-III. Agency: CMSA. Primary contractor: CAST/CASC. Status: Operational. First launch: 1999-11-20. Last launch: 2016-10-19. No. of flights: 11. Launch vehicle: CZ-2F. Launch complex: Jiuquan-SLS1. Orbit: 300—400 km LEO, 42.5º inclination. Mass (gross): 8,130 kg. Mass (orbital): 7,800 kg. Propellants: N2O4/UDMH.
The People’s Republic of China (PRC) embarked on a manned spaceflight programme in 1992, with the goal of constructing a manned space station on Low Earth Orbit by 2022. Phase-I of the programme aimed to develop a manned spacecraft vehicle that can carry astronauts to orbit and bring them back to Earth safely. The resulted Shenzhou spacecraft made its first unmanned test flight in November 1999, and sent China’s first astronaut Yang Liwei to orbit in October 2003.
Following an unsuccessful attempt to send human into space in the early 1970s, discussions over human spaceflight re-emerged in the mid-1980s against a background of vigorous competition amongst space fairing nations to establish their presence in Earth orbit. In March 1986, the Chinese government launched the 863 Programme, a state-sponsored initiative intended to nurture the country’s fundamental research in new and creative technologies. The space section of the programme was tasked with the conceptual study of two systems: a manned space station and a crew transportation system including its launch vehicle.
While the goal of constructing an Earth-orbiting manned space station was never a point of contention, there were different views over the choice of the means to transport astronauts to and from the space station. An internal debate within the Chinese space community in the late 1980s eventually led to the decision in favour of the manned capsule vehicle over a space shuttle system. Despite some doubt within the scientific community and government over China’s financial and industrial capabilities to support manned spaceflight, the Chinese political leadership finally took the decision in 1992 to embark on a manned spaceflight programme (Project 921).
After some initial conceptual study, the Chinese space industry settled on a three-module manned capsule design modelled after the Russian Soyuz-TM. The spacecraft, named Shenzhou (“Devine Vessel”), features a forward orbital module, a re-entry module that can accommodate three astronauts, and an aft service module. The vehicle weighs just under 8,000 kg and could be launched atop a man-rated version of the CZ-2E orbital launcher.
The primary contract for developing the Shenzhou spacecraft was awarded to the Beijing-based China Academy of Space Technology (CAST), with Shanghai Academy of Spaceflight Technology (SAST) sharing some development tasks, including the spacecraft’s service module, power system, propulsions, and docking system. The spacecraft’s environment control and life support system was developed by Beijing Institute of Space Medicine and Engineering (507 Institute). The Beijing-based China Academy of Launch Vehicle Technology (CALT) was tasked with the development of the man-rated spacecraft launcher designated CZ-2F.
The scope of Project 921 was beyond simply developing a spacecraft vehicle and its orbital launcher. The programme also included an upgrade of China’s entire spaceflight infrastructure:
- A new 2.3 square kilometres (577 acres) facility that would serve as a R&D hub, astronaut training base, and mission control centre for China’s space programme was constructed at Tangjialing, in the northwest suburbs of Beijing. CAST’s Shenzhou assembly, testing and integration (ATI) facility, the Astronaut Centre of China (ACC), and the Beijing Aerospace Control Centre (BACC) are all located inside the centre.
- A new launch site was constructed at the Jiuquan Satellite Launch Centre (JSLC) in northwest China. The launch site included a launch pad (Pad 921) dedicated for manned spaceflight missions, linked by a 1.5 km rail track with the Vehicle Assembly Building located inside the technical centre nearby. This was China’s first launch complex to have adopted a vertical rollout procedure, where the assembled launch vehicle and spacecraft stack is rolled out to launch pad in a vertical position atop a mobile launcher platform, allowing less time to be spent on the launch pad for vehicle assembly and checkout.
- China’s existing telemetry, tracking and command (TT&C) network received a modernisation upgrade with a unified S-band (USB) system to track and communicate with the launch vehicle and spacecraft during their flight. This network consisted of ground tracking stations located within a belt stretching from western frontier to the east coast of China mainland, as well as four overseas tracking stations located in Pakistan, Namibia, and Kenya. Additional tracking and communications coverage was provided by four Yuanwang tracking ships deployed to the West Pacific, South Pacific, South Atlantic, and Indian Ocean. The tracking stations and ships are linked together by a cable and wireless communications network with the Launch Mission Control Centre (LMCC) of the Jiuquan Satellite Launch Centre, the Xi’an Satellite Control Centre (XSCC), and the Beijing Aerospace Control Centre (BACC).
- The primary landing zone of the Shenzhou re-entry module was set up at Siziwang Banner, Inner Mongolia. The landing zone is supported by forward radar station to capture the trajectory of the returning vehicle, the primary measurement site to provide TT&C and weather services, and the ground/air search and rescue teams. A backup landing zone was set up near the Jiuquan Satellite Launch Centre. During launch, additional emergency landing zones were set up along the downrange flight path, both on land and in the East China Sea.
- A group of 14 astronaut candidates selected from over 1,500 military fighter jet pilots began a four-year training cycle in 1998 to prepare them for the orbital flight missions aboard the Shenzhou vehicle. Their training included orientation and foundation theoretical knowledge, physical and psychological training, Shenzhou flight procedures, emergency procedures, parachute jumping, land and water egress training, survival techniques in desert, sea and jungle, and foreign languages.
- The China Academy of Sciences (CAS) was tasked with the development of application payloads to be carried on the Shenzhou vehicle as secondary missions, ranging from micro-gravity crystal growing experiment, life sciences experiment with animals and plants, protein crystallisation experiment, gravimetry devices, space environment probing devices, to Earth observation packages.
The implementation of Project 921 is carried out by the military-run China Manned Space Office (921 Office), which oversaw a total of 7 key projects:
- 921-1: Astronaut selection and training
- 921-2: Space applications
- 921-3: Shenzhou crew vehicle
- 921-4: CZ-2F launch vehicle
- 921-5: Jiuquan launch site
- 921-6: Telemetry, tracking and command
- 921-7: Recovery site
Following an 18-month delay in the development, an experimental vehicle of the Shenzhou spacecraft finally made the first unmanned flight test on 20 November 1999, marking the first major milestone in the spacecraft’s development. This was followed by three more unmanned flight test missions between January 2001 and January 2003 in order to fully validate the spacecraft’s design and identify potential flaws, before a manned mission could be launched. On 15 October 2003, Air Force Lt. Col. Yang Liwei became the first Chinese citizen to have flown in space aboard the Shenzhou 5 vehicle. Two years later, a second mission Shenzhou 6 was launched, with two astronauts flying in orbit for 4 days and 19 hours.
In Phase-II of the manned spaceflight programme that began 2008, the Shenzhou spacecraft has been used to demonstrate advanced spaceflight techniques including extravehicular activity (EVA), orbital rendezvous and docking, and the transportation of astronaut crews to and from the Space Laboratory modules in orbit. The spacecraft is expected to remain in service well into Phase-III of the manned spaceflight programme, when a multi-module manned space station will be constructed.
The Shenzhou is a modular assembly consisting of a forward cylindrical orbital module, an aerodynamic re-entry module, and an aft cylindrical service module with a pair of solar panel wings. A launch escape tower is attached to the front-end of the assembly and is jettisoned 2 minutes after the lift-off. The crew stays inside the habitable re-entry module during launch and re-entry and controls the spacecraft from there. The orbital module, which is also habitable, provides additional habitable space for the crew during orbital flight.
The spacecraft is launched atop the CZ-2F launcher rocket from Pad 921 (SLS-1) at the Jiuquan Satellite Launch Centre (JSLC), and operates in a 343 km near-circular orbit inclined at 42.5° to the Earth equator. It is capable of carrying up to three astronauts to fly in low Earth orbit (LEO) for up to 7 days in a solo flight mission. When the mission is completed, the orbital and service modules are discarded, while the heat-shield-protected re-entry module carrying the crew makes an unpowered ballistic descent through the atmosphere and then deploys parachutes and landing rockets for a soft-landing.
The spacecraft assembly is nearly 9 m in total length (excluding the launch escape tower), 2.5 m in diameter, with a gross launch mass of 8,130 kg and an orbital mass of 7,800 kg. It consists of 13 sub-systems: space frame, guidance navigation and control (GNC), data management, telemetry and communications, thermal control, propulsion, power, mission payload, environment control and life support system (ECLSS), crew, instruments and lightening, emergency rescue, and re-entry and landing. It is fitted with a total of 52 engines, including four main engines and 48 small-thrust control vectors (16 on the orbital module, 8 on the re-entry module, and 24 on the service module).
- The orbital module at the front of the spacecraft assembly is used to carry key equipment including a space toilet, and also provides additional habitable space for the crew to live and conduct scientific experiments during orbital flight. The module is 2.80 m in length, 2.25 m in diameter, with an internal volume of 8 cubic metres and an orbital mass of 1,500 kg. The module is connected to the re-entry module via a 65 cm diameter cylindrical hatch, which is sealed off during ascent, rendezvous docking, and re-entry. A large cylindrical hatch located on the side the module allows the crew to enter the spacecraft before launch, and can also be used for the astronauts to exit and re-enter the spacecraft during EVA. There is a third, smaller cylindrical hatch on the side of the orbital module in some early Shenzhou missions, possibly used as a window for Earth-observation payload.
- For the early solo flight variant of the Shenzhou vehicle, the orbital module was fitted with its own independent altitude control, propulsion, telemetry and communication systems, as well as a second pair of smaller solar panel wings and 16 thrusters (in four groups of 4 thrusters). This design allowed the module to remain flying in orbit in an automated mode for another six months after being jettisoned from the re-entry module at the end of the manned mission.
- Chinese spacecraft engineers originally envisioned to use the jettisoned orbital module as the target for the next Shenzhou spacecraft to practice orbital rendezvous and docking, but this idea was later abandoned. Instead, after the jettison the orbital module served as an orbital bus to carry scientific experiment or Earth-observation packages, with additional mission payload attached externally to the front of the module.
- The Shenzhou 7 mission in 2008 featured a specially modified orbital module which doubled as an airlock and storage space for two EVA spacesuits. The spacewalking astronauts exited and returned to the spacecraft vehicle via the large cylindrical hatch on the side of the module, while the hatch connecting to the re-entry module remained sealed off throughout the EVA. This orbital module design lacked the automated orbital flight ability and was simply discarded and de-orbited at the end of mission.
- From the Shenzhou 8 mission onwards, the Shenzhou spacecraft has been built in the crew transport configuration, which features an APAS-style docking port and an optical and radar-based automated rendezvous and docking system at the front end of its orbital module. Designed by SAST and believed to have been derived from the Russian APAS-89, the docking system features a single androgynous docking port, radio beacons, transponders, communication antenna, UHF radar, laser rangefinder, and electro-optical tracking system. The inside diameter of the docking port tunnel is 0.8 metre. During a rendezvous docking, the Shenzhou vehicle chases and closes in the space station though a V-bar approach from behind.
- The re-entry module provides a fully pressurised and habitable living space for the crew during the ascent and re-entry phase of the flight. The module accommodates Soyuz-style moulded seats for up to three crew members, flight instrument panel, control sticker, periscope, and the communications system, with an internal volume of 8 cubic metres. There are two windows for the crew to observe the outside.
- The module is fitted with eight (in four pairs) 5 N control engines, including 2 pitch/yaw thrusters, 2 translation thrusters, and 4 roll thrusters to maintain its flight status during re-entry.
- During the descent stage of the flight, the re-entry module first makes an unpowered (but controlled) ballistic descent through the atmosphere, with its heat shield protected blunt end pointing forward. The module has a spherical aerodynamic design, with its centre of mass deliberately and precisely offset from its axis of symmetry to achieve an angle of attack during the free fall. This allows the yield of a small lift to reduce g-force from 8—9 g for a purely ballistic trajectory to 4—5 g during the hypersonic free-fall, as well as greatly reducing the peak re-entry heat. In an emergency situation, the module can also re-entry using a purely ballistic trajectory, which would increase the g-force to 8—9 g. If necessary, the module can splashdown on water and then remain afloat.
- The re-entry module is fitted with five parachutes: a pilot chute (4.25 m2 surface area), a second pilot chute (surface area: 0.7 m2), a drogue chute (surface area: 24 m2), a main parachute (surface area: 1,200 m2), and a backup parachute (surface area: 760 m2). The parachutes are deployed from the altitude of 10,000 m.
- The 280 kg heat shield is jettisoned before landing so that the four landing rockets at the bottom of the module could fire to allow a soft-landing.
- The inhabitable service module is larger than that of the Soyuz-TM. It accommodates the navigation, communications, flight control, thermal control, propulsion systems, as well as batteries, oxygen tanks, and propellant tanks. It has a pair of adjustable solar panel wings 17 m in span to obtain maximum solar insulation regardless of the spacecraft’s flight status.
- The propulsion system consists of four high-thrust main engines and 24 smaller-thrust control vectors, plus four 230-litre propellant tanks containing a total of 1,000 kg N2O4/MMH liquid propellant. The four main engines, each rated at 2.5 kN, are located at the base of the spacecraft’s service module. There are eight (in four pairs) 150 N pitch/yaw thrusters, eight (in four pairs) 5 N pitch/yaw thrusters, and eight (in four pairs) 5 N roll / translation thrusters.
- The launch escape assembly incorporates the launch escape tower, the orbital module, the descent module, the upper portion of the payload fairing and four foldable grid aerodynamic flaps. In case of an anomaly during the launch, the assembly with the crew can be pulled away from the remainder of the launch vehicle within seconds, by rockets mounted on the launch escape tower above the payload fairing. The whole assembly is 15.1 m in length and 3.8 m in diameter, and has a total mass of 11,260 kg. It is powered by the solid fuel rocket motors mounted on the launch escape tower and payload fairing. The two-piece payload fairing is also equipped with rocket motors for high-altitude escape.
- The launch escape tower is 8.35 m in length and fitted with six rocket motors: four main escape motors, a pitch motor and a separation motor with eight nuzzles. The main four main escape motors are mounted symmetrically on the lower part of the launch escape tower at an angle of 30° to the axis of the launch vehicle. Above them are eight smaller separation motors. The pitch motors are mounted at the top of the tower.
- The Environmental Control and Life Support System (ECLSS) ensures a habitable and safe environment for the onboard crew throughout the flight mission. It consists of the environment control system, oxygen and other gases storage tanks, water supply and processing system, astronaut waste disposal and collection system (‘space toilet’), fire/smoke detectors, and fire suppression system. During the flight mission, every day a typical crew member consumes 0.83 kg oxygen and 1.8 litre of water, and produces 0.9 kg carbon dioxide. The Shenzhou vehicle can create and maintain an inside atmosphere similar to that on Earth, with conventional air (nitrogen/oxygen). A liquid-circulating temperature control unit maintains the temperature inside the habitable modules between 17—25°C. Air dampness is maintained between 30—70%. An air ventilation and purification system detects and absorbs dusts, carbon dioxide and carbon monoxide.
- The Shenzhou orbital module is fitted with a space toilet, which uses a vacuum system to collect human waste of the onboard crew. A food heater can provide the crew with hot meals during the flight. The crew is required to wear the intra-vehicular activity pressure suits during launch, docking, undocking and descent. The suit, which was based on the Russian Sokol design, can protect the crew members in the event of hull breach or pressure loss.
China’s early human spaceflight programme — China’s aspiration for human space exploration emerged in the 1960s, nearly four decades before the country’s first astronaut Yang Liwei flew in the historical Shenzhou 5 mission. The first serious plan to send astronauts to Earth orbit was initiated in 1971, with the development of the two-seater Shuguang 1 manned capsule. However, political turmoil, coupled with technical and financial difficulties, eventually led to a quiet cancellation of the mission in the late 1970s.
Origin of the Shenzhou spacecraft — China’s human spaceflight plan re-emerged in the mid-1980s against a background of vigorous competition amongst space fairing nations to establish their presence in Earth orbit. In March 1986, the Chinese government launched the 863 Programme, a state-sponsored initiative intended to nurture China’s fundamental research in new and creative technologies. The aerospace section of the 863 Programme was focused on the conceptual studies of a manned Earth-orbiting space station, as well as the crew transportation system and its launch vehicle.
The development of the Shenzhou — The concept of a capsule-type crew vehicle was developed in the late 1980s under the 863 Programme. The development of the crew vehicle began in 1992, with the contract awarded to China Aacdemy of Space Technology (CAST). The first experimental Shenzhou test vehicle made a successful maiden flight in November 1999.
Shenzhou mission profile — The launch and recovery of the Shenzhou spacecraft.
Shenzhou test flight missions — A total of four unmanned flight tests of the Shenzhou spacecraft vehicle were conducted between November 1999 and January 2003, in order to validate the design and technology of the spacecraft vehicle, its launch vehicle, and the ground support systems. These four mission not only demonstrated a reliable transportation system to send astronauts into orbit and return them back to Earth safely, but also brought the human spaceflight programme (Project 921) previously shrouded in secrecy into the public domain.
Shenzhou 5 — The China Manned Space Programme reached a major milestone on 14 October 2003, when the 38-year-old former fighter pilot Lt. Col. Yang Liwei became the first Chinese astronaut to have flown in Earth orbit aboard the Shenzhou 5 spacecraft. The successful mission also made China the third country in the world, after Russia and the United States, to possess the capability of sending human into space independently. Yang’s mission goal was rather conservative. He was the only crew member for the mission. He remained inside the re-entry module throughout the entire flight mission, and did not take off his pressure suit. Despite some minor glitches, Yang returned to Earth safe and well after orbiting the Earth 14 times in 21 hours 23 minutes.
Shenzhou 6 — The Shenzhou 6 mission was the sixth flight of the Shenzhou manned capsule, and the second manned mission. The purposes of the mission were to demonstrate the human space flight technology and test the design of the spacecraft and ground support systems. The mission was also the last mission of Phase-I of the China Manned Space Programme (Project 921), showing that China had grasped the technology to put humans into Earth orbit and return them to Earth safely. The Shenzhou 6 mission had a crew of two, with Fei Junlong as Mission Commander and Nie Haisheng as Flight Engineer.
Shenzhou 7 — Shenzhou 7 was China’s third manned spaceflight mission. The main objective of the mission was to demonstrate extra-vehicular activity (EVA). Secondary objectives included launching a macro-satellite Banxing 1 (BX-1) from the spacecraft to perform a formation flight, and to test the voice and data communication with the ground via the Tianlian 1 (TL-1) tracking and data relay satellite (TDRS). It was also the first time that the Shenzhou vehicle carried three astronauts to orbit. The programme was approved in December 2004, but the launch did not take place until September 2008, almost a year behind the original schedule.
Shenzhou 8 – Unmanned mission and the eighth flight of the Shenzhou spacecraft, intended to demonstrate rendezvous and docking between two unmanned space vehicles. The mission provided useful engineering experience for subsequent manned rendezvous and docking missions and the construction of the future space station. Although orbital rendezvous docking was perfected by the United States and Russia in the 1960s, China had to develop the technique almost from scratch. Shanghai Academy of Spaceflight Technology (SAST) began to develop an androgynous docking mechanism in the mid-1990s, but the system was not ready until 2010 due to technical obstacles.
Shenzhou 9 — The ninth flight mission of the Shenzhou spacecraft, and the fourth crewed mission of China’s manned space programme. The objective of the mission was to perfect the orbital rendezvous docking technique, using both automated and manual docking methods. The crew of three astronauts, Jing Haipeng, Liu Wang and China’s first female astronaut Liu Yang, spent 10 days onboard the Tiangong 1 space module to experience orbital living and working. The Shenzhou 9 mission achieved a number of ‘Firsts’ in China’s manned spaceflight history, including the longest mission duration, the first rendezvous docking with crew onboard the Shenzhou vehicle, the first manual docking, the first Chinese woman in space, and the first two-mission astronaut (Jing Haipeng).
Shenzhou 10 — The fifth manned spaceflight mission, and the last of the three Shenzhou missions intended for the test of the rendezvous and docking technique with the Tiangong 1 space laboratory. The mission lasted for 15 days, a new record in mission duration. Shenzhou 10 was also the first operational flight mission, with four main objectives: to ferry the crew and materials between the earth and the Tiangong 1 space laboratory and test the performance of the Shenzhou capsule and its docking system; to further demonstrate the crew’s ability to live and operate in the Shenzhou-Tiangong spacecraft complex; to demonstrate the adaptability and efficiency of the crew in orbit and also to broadcast a classroom lesson to Chinese students; to further perfect the coordination between different systems in the manned space programme.
Shenzhou 11 — The sixth manned spaceflight mission to send a crew of two astronauts to the Tiangong 2 space laboratory module, where they will spend 30 days living and working in orbit.
Date Mission Type Crew Launch Site Launch Vehicle ----------------------------------------------------------------------------------------------- 1999-11-20 Shenzhou 1 Test flight None Jiuquan CZ-2F (Y1) 2001-01-10 Shenzhou 2 Test flight None Jiuquan CZ-2F (Y2) 2002-03-25 Shenzhou 3 Test flight None Jiuquan CZ-2F (Y3) 2002-12-30 Shenzhou 4 Test flight None Jiuquan CZ-2F (Y4) 2003-10-15 Shenzhou 5 Crewed Yang Liwei Jiuquan CZ-2F (Y5) 2005-10-12 Shenzhou 6 Crewed Fei Junlong Jiuquan CZ-2F (Y6) Nie Haisheng 2008-09-25 Shenzhou 7 Crewed Zhai Zhigang Jiuquan CZ-2F (Y7) Liu Boming Jing Haipeng 2011-11-02 Shenzhou 8 Unmanned test None Jiuquan CZ-2F (Y8) 2012-06-16 Shenzhou 9 Crewed Jing Haipeng Jiuquan CZ-2F (Y9) Liu Wang Liu Yang 2013-06-11 Shenzhou 10 Crewed Nie Haisheng Jiuquan CZ-2F (Y10) Zhang Xiaoguang Wang Yaping 2016-10-17 Shenzhou 11 Crewed Jing Haipeng Jiuquan CZ-2F (Y11) Chen Dong