The second flight of China’s new medium-lift Lengthy March 7A rocket efficiently positioned an experimental satellite tv for pc into orbit Thursday, following a failed launch of the identical configuration final 12 months attributable to an issue in a booster liquid oxygen system.
The Lengthy March 7A rocket took off from the Wenchang launch base on Hainan Island in southern China at 12:51 p.m. EST (1751 GMT) Thursday, or 1:51 a.m. Beijing time Friday, based on China Aerospace Science and Expertise Corp., or CASC, the most important state-owned contractor for the Chinese language area program.
The deployed its payload into an elliptical, or oval-shaped, orbit ranging between 155 miles and 22,270 miles (250-by-35,840 kilometers), with an inclination of 19.5 levels to the equator, based on unbiased monitoring information launched by the U.S. navy.
China declared the mission a hit. The state-run Xinhua information company stated the Shiyan 9 spacecraft launched by the Lengthy March 7A rocket is designed “for in-orbit checks of recent applied sciences together with area atmosphere monitoring.”
The Shiyan household of Chinese language satellites are designed for know-how demonstrations. Shiyan means “experiment” in Chinese language.
Shiyan 9 is predicted to make use of its personal propulsion system to lift the perigee, or low level, of its orbit to geostationary altitude of greater than 22,000 miles, or almost 36,000 kilometers, over the equator. In that orbit, Shiyan 9 will circle Earth on the similar price of the planet’s rotation, giving the satellite tv for pc a set place relative to the bottom.
The launch Thursday marked the fourth flight of a Lengthy March 7 rocket, and the second utilizing the Lengthy March 7A configuration.
The Lengthy March 7 is designed to launch medium-sized satellites, comparable to Tianzhou resupply ships for China’s deliberate area station in low Earth orbit. The Lengthy March 7A variant flies with a reignitable third stage, giving the rocket a capability to deploy satellites heading into increased orbits.
The Lengthy March 7A rocket stands about 197 ft, or 60 meters, tall and might carry payloads of as much as 15,400 kilos, or 7 metric tons, into geostationary switch orbit. That’s the similar sort of orbit the Lengthy March 7A reached with the Shiyan 9 satellite tv for pc Thursday.
China debuted the Lengthy March 7A rocket in March 2020 after two profitable flights of the fundamental Lengthy March 7 configuration in 2016 and 2017. However the Lengthy March 7A failed to succeed in orbit and fell again to Earth a couple of minutes after liftoff from Wenchang.
A report printed by The Paper, a government-run digital newspaper based mostly in Shanghai, stated the Lengthy March 7A launch failure final 12 months was attributable to low stress in a liquid oxygen inlet feeding one of many rocket’s booster engines. Engineers traced the issue to “cavitation” within the liquid oxygen system feeding the booster, resulting in pressures too low to permit the engine to proceed firing, based on The Paper.
The Lengthy March 7A is powered by 4 strap-on boosters powered by kerosene/oxygen-fed YF-100 engines, and a central core stage with two YF-100 engines. The rocket’s second stage has 4 YF-115 engines, additionally fed by kerosene and liquid oxygen, and two hydrogen-fueled YF-75 engines are on the brand new third stage added to create the Lengthy March 7A configuration.
The failure final 12 months occurred close to the tip of the burn by the 4 boosters and core stage engines, almost three minutes into the mission.
The YF-100 engine is used on a number of of China’s new rockets. The strap-on boosters of China’s heavy-lift Lengthy March 5 rocket are powered by YF-100 engines, and the identical engine sort flies on China’s light-class Lengthy March 6 launcher and the Lengthy March eight rocket.
Earlier than the Lengthy March 7A’s second flight Thursday, China efficiently launched three Lengthy March 5 rockets, one Lengthy March 6, and one Lengthy March eight mission final 12 months.
China’s new Lengthy March 5, 6, 7 and eight rockets are designed to finally substitute the nation’s older Lengthy March automobiles, which use poisonous propellants and launch from inland spaceports, usually dropping spent phases close to populated areas.
The Lengthy March 7A rocket is a possible alternative for the Lengthy March 3B for launches with geostationary satellites, providing a 25% enchancment in payload capability to geostationary switch orbit.
In accordance with CASC, the Lengthy March 7A rocket will launch three to 5 occasions per 12 months sooner or later, and engineers are creating a bigger diameter payload fairing to accommodate bigger satellites. Future upgrades to the Lengthy March 7A will permit it to launch payloads straight into zero-degree inclination geostationary orbits, and deploy spacecraft heading to the moon and different planets, CASC stated in an announcement.
The subsequent launch from Wenchang, the place launching rockets drop boosters over the ocean as a substitute of land, is scheduled in late April with a Lengthy March 5B rocket carrying the Tianhe core module for China’s area station.
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