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China plans to launch a new generation crew space capsule at 10:06 UTC on May 5, 2020, using the first Long March-5B rocket. The launch will take place from the Launch Complex LC101 of the Wenchang Space Flight Launch Center in Hainan.
(Main image via CCTV)
A landing is expected between 05:02 and 05:42 UTC on May 6, in an area east of the Jiuquan Satellite Launch Center in the Inner Mongolia Autonomous Region.
Originally, the launch was scheduled for April 24, around the 50th anniversary of the launch of the first Chinese Dongfanghong-1 satellite, but was delayed due to an undetermined technical problem with the Long March-5B launch vehicle (Y1).
On its first flight, this mission can be seen primarily as a test of the Long March-5B configuration for the space station’s Tianhe core module, including the fairing test to be used when China begins construction of its Tiangong modular station. This explains the fact that no launch escape / abort system was used with the new crew vehicle.
This is a major milestone in the future of the Chinese manned space flight program, and a moral boost to China’s launch manifesto after two almost consecutive launch failures.
The New Generation Crew Space Capsule
Housed within a 20.5 meter long cavernous payload fairing, the mission of this new generation manned space vehicle will be to test key technologies such as controlling its re-entry into the atmosphere from moon speeds and its protection and recovery technology. heat, specifically parachute and multiple airbags.
The prototype of the next generation of the Chinese crew space capsule
The new capsule will go into an 8,000 km high orbit before reentering at high speed.
The new vehicle will be used in both low-Earth orbit missions and deep-space exploration flights. Capable of carrying six crew members (or 500 kg of cargo with a crew of three), the new capsule has a total length of 8.8 meters, a diameter of 5 meters and a launch weight of 21,600 kg.
The new vehicle, consisting of a service module and a return capsule, was designed to be reused ten times.
The service module is discarded before reentering. Contains liquid oxygen and liquid hydrogen for the operation of fuel cells and water production (as well as to provide oxygen for the crew), fuel cells, solar panels, and batteries to provide electrical power to the spacecraft, computer systems for guide and sensors, fuel and oxidant for reaction and propulsion control systems and thermal control systems for proper heating and cooling.
The return capsule is the reusable part of the new generation Chinese crew space capsule. It provides pressurized habitat for the crew, and also provides storage for consumables and research instruments. Depending on the mission, it can be adapted with a docking port for crew transfers.
Docking port for the Next Generation Chinese Crew Capsule – via SAST
The development team used new materials and a new structure to make the thermal protection capacity three to four times greater than that of the Shenzhou spacecraft.
The new vehicle has two versions. A LEO version (with a launch mass of around 14,000 kg) and a Beyond-LEO version (21,600 kg). The main difference between both vehicles is in the service module.
The Long March-5B
Aiming to have a space launcher capable of orbiting heavy loads into Geostationary Transfer Orbit (GTO), Low Earth Orbit (LEO), and interplanetary missions, China approved the development of the Long March-5 launch vehicle family in June 2004.
Long March 5 launches the Shijian-20 satellite in December 2019
The new family of launchers would meet the needs of the future launch services market, would be used to launch modules for a large-scale space station, would help to maintain the trend of development of China’s launch vehicle technology, and would drive the development of the economy. and the high technologies related in China with the development of new rocket motors, new welding techniques, updates to flight control systems, etc.
The new development program would design a series of launch vehicles instead of a launcher made for a specific mission.
This is to improve China’s ability to access space; it would apply advanced technologies, such as the large diameter core and the powerful push motor, to dramatically increase launch capacity, to launch payloads of 25 tons to LEO and 14 tons to GTO; design a series of launch vehicles based on the principle of generalization, serialization and modularization, to meet the launch needs of different payloads; to use non-toxic and non-polluting propellant; and be of low cost, high reliability and convenient for testing and operation.
The launch system envisioned a modular concept using two newly developed engines and three standard modules. Originally, the plan included three main classes: 5 meter diameter core variants, a 3.35 meter diameter core variant, and a 2.25 meter diameter core configuration.
The three standard modules were the H5-1 module (diameter of 5 meters with a length of 31.0 meters, equipped with two 50-ton LH / LOX engines, with a mass of 175 tons), the K3-1 module (diameter of 3.35 meters with a length of 26.3 meters, equipped with two 120-ton KO / LOX engines, with a mass of 147 tons) and the K2-1 module (2.25-meter diameter with a length of 25.0 meters, equipped with a KO / LOX 120 ton motor, which has a mass of 69 tons).
From these initial concepts, the Long March-6 and Long March-7 launch vehicles were developed. A number of variants were proposed for the heavy launcher. Using the 5 meter diameter center stage and different combinations of belt reinforcements and an upper stage, six variants were proposed to achieve different payload capacities.
Configuration A could launch 18 tons to LEO, while configuration B and C would be able to lift 25 tons and 10 tons to LEO, respectively. For GTO, Configuration D would be able to launch 10 tons, while Configuration E and F would be able to lift 14 tons and 6 tons to GTO, respectively.
Finally, only two variants were developed: the basic two-stage Long March-5 variant designed for GTO missions, and the single-stage Long March-5B designed for LEO missions. Both variants are equipped with four 3.35 m diameter strap reinforcements.
Long March 5B during deployment to LC101
The Long March-5 is considered the basic variant of this family of launchers. It is a two-stage central vehicle (5 meters in diameter) with four belt reinforcements (3.35 meters in diameter), capable of launching 14,000 kg at GTO. The total length is 56.97 meters, it has a gross mass of 869,000 kg and a takeoff thrust of 10,573 kN.
The Long March-5B is a central single-stage vehicle (5 meters in diameter) with four belt reinforcements (3.35 meters in diameter), capable of throwing 22,000 kg at LEO. The total length is 53.70 meters, it has a gross mass of 837,500 kg and a takeoff thrust of 10,573 kN.
The maiden flight was scheduled for 2013, but the Chinese Academy of Vehicle Launch Technology (CALT) and the Shanghai Academy of Space Flight Technology (SAST) would have to endure a difficult path for the first flight. Facing huge technical challenges, the development of the YF-100 and YF-77 engines would delay the development of the new family of launch vehicles.
The length of the first stage is 31.02 meters, with a diameter of 5.00 meters. The first stage is equipped with two YF-77 engines that consume LOX / LH. The first stage has a gross mass of 175,800 kg with an empty mass of 17,800 kg.
Strap-on amplifiers are 26.28 meters long and 3.25 meters in diameter. Each strap reinforcement is equipped with two YF-100 motors. The gross mass is 147,000 kg with an empty mass of 12,000 kg. The YF-100 engine consumes LOX and kerosene.
The second stage is 12.00 meters long, with a diameter of 5.00 meters. It is equipped with two YF-75D engines, consuming LOX / LH. The second stage has a gross mass of 26,000 kg with an empty mass of 3,100 kg.
The Long Payload Fairing March 5B
The YF-77 engine, developed by the Academy of Aerospace Launch Propulsion Technology (AALPT), is a high-performance and reliable booster designed for the Long March-5 family. This is the first high-thrust cryogenic engine developed in China, taking a technological leap forward compared to previous oxygen / hydrogen cryogenic engines such as the YF-75, which powers the upper stage of the LM-3A / 3B.
The engine uses a gas generator cycle with LOX / LH2 cryogenic thrusters. Two YF-77 engines fly in the first stage of the Long March-5, and each engine delivers 700 kN idle at an oxidizer to fuel mixture (O / F) ratio of 5.5. The YF-77 develops 700 kN under vacuum and 510 kN at sea level with an Isp of 430 seconds (empty) and 310.2 seconds (sea level). The recording time is 520 seconds.
Development of the YF-100 began in 2000 at the Academy of Aerospace Liquid Propulsion Technology. The engine was certified by the State Administration of Science, Technology and Industry for National Defense (SASTIND) in May 2012. It is a staged combustion cycle engine that develops 1,199.19 kN at sea level with an Isp of 300 seconds (vacuum thrust is 1,339.48 kN; vacuum Isp is 335 seconds). Recording time is 155 seconds. The YF-100 is also used in the CZ-6 launch vehicle.
The YF-75D engine is a LOX / LH2 closed expansion cycle engine that is designed to meet the second-stage propulsion requirements of the new generation LM-5 launch vehicle for its performance, reliability, development cost, schedule , etc. The YF- 75D engine is capable of speeding up its multiple start and mix ratio to suit multiple missions. The YF-75D engine has two turbofan engines powered by gaseous hydrogen. They are designed in series and completed with the entire engine. The YF-75D develops 88.26 kN under vacuum with an Isp of 442 seconds. Recording time is 780 seconds.
The payloads orbited by the LM-5 are initially protected by a payload fairing with a diameter of 5.2 meters and a length of 12.5 meters.
Wenchang Space Launch Center
With the first orbital flight in June 2016, the Wenchang Space Launch Center is located in the northeast corner of Hainan Island on the south coast of China.
The new launch complex offers greater versatility than the other three launch sites do not. Wenchang provides an increase in launch vehicle performance obtained from Earth’s rotational speed because it is closer to Earth’s equator. This reduces the number of propellers required for the satellite to maneuver from the transfer orbit to GEO.
The launch vehicle can fly from the launch site to the southeast direction to the South Pacific, preventing the possibility of rocket debris falling in any populated area.
The center is equipped with two launch complexes. Launch Complex LC101 is used for the Long March-5 launch vehicle family, while Launch Complex LC201 is used for the Long March-7 launch vehicle.
Long March 5 at LC101, Wenchang Satellite Launch Center, before launching Shijian-20 in December 2019 – via Su Dong
Both pads are similar and are equipped with a fixed umbilical tower and underground flame baffle trenches and ducts. Similar to what happens in the other Chinese launch centers, the umbilical towers have swing arms to allow technicians to access and inspect the launch vehicle and payload.
The launch pads in the new launch complex use a sound suppression system, spraying large volumes of water on the launcher platform and in the flame deflecting trenches below to dampen the sound waves generated by the rocket engines.
The launching pads are served by two vehicle assembly and integration buildings. Launch Complex LC101 is served by Building 501, while Launch Complex LC201 is served by Building 502.
Each building is 99.4 meters high, allowing the launch vehicle to be assembled and tested in a full vertical stacked position. This is a new approach to preparing the launch vehicle for flight because in the other Chinese launch centers launchers are stacked and tested for flight on launch pads.
After stacking in the vehicle assembly and integration building on top of a mobile launch pad, the launcher is placed on the launch pad. The journey takes several minutes to cover the 2,800 meters that separate the vehicle’s assembly and integration buildings and launch platforms. After reaching the launch pads, the mobile structure is placed above the flame ditch and the necessary umbilical connections are established between the fixed structures and the mobile platform.
