China is about to introduce to the world its Long March 7 rocket, the newest addition to the country’s fast expanding fleet of launch vehicles. The booster is expected to blast off from the Wenchang Satellite Launch Center, located on the island of Hainan, most probably on Saturday, June 25, however the exact time of the launch is still undisclosed.
The launch window extends till June 29, thus we could see the start of the mission even in the middle of next week.
The debuting Long March 7 rocket is a 174.2-feet (53.1-meters) tall medium-lift two-stage launch vehicle. It was developed by the China Academy of Launch Vehicle Technology (CALT) and is based on the Long March 2F rocket.
The nearly 600-metric-ton launch vehicle is 11 feet (3.35 meters) in diameter and is capable of lifting up to 13.5 metric tons to a low-Earth orbit (LEO) and about 5.5 metric tons to a sun-synchronous orbit (SSO). The rocket is fitted with four strap-on boosters powered by YF-100 engines. The boosters are attached to the first stage of the launch vehicle which is 11 feet (3.35 meters) in diameter and is equipped in two YF-100 engines itself. The second stage has the same diameter as the first stage, however it is powered by different engines – a set of four YF-115.
The newly-developed rocket is designed to transport cargo for China's planned space station and is expected to become the main launcher for future space missions. Currently it is the country’s most powerful launch vehicle.
China hopes that its new Long March 7 rocket will be more environment friendly than previous launchers in the series. According to Hu Xiaojun, the rocket’s deputy chief designer assistant, the new booster relies on liquid oxygen and kerosene as fuel, cheaper and less dangerous than the propellants used by some of the earlier launch vehicles.
“During the launching process, we will also monitor all the environmental data to provide a reference for future rockets," said Zhang Zhengping, expert of CALT.
Long March 7 rocket is designed to be also more weather-resistant than its predecessors. The booster is waterproof and can be launched on rainy days. Moreover, the rocket is equipped with wind-resistance devices allowing it to withstand gales of wind during its flight into space.
On its maiden mission, the Long March 7 launcher will fly into space carrying a prototype of the country’s next-generation manned capsule and several small satellites. Little is known as about the mission’s payload as the Chinese media released only brief information about the spacecraft. According to various press releases, it will be a scaled-down model of a re-entry capsule developed to test the descent capabilities of future crewed flights.
“The launch will open a new chapter in the history of Chinese space exploration,” a space scientist involved in the development of the new Long March rockets said.
The capsule features a Global Navigation Satellite System (GNSS) antenna, parachutes, and an antenna specially designed to prevent radio silence during hypersonic re-entry. The spacecraft is being designed with the aim to serve as future transportation system for cargo and crews to LEO an beyond, including possible missions to the moon.
The Long March 7 rocket was delivered to the Wenchang Satellite Launch Center in May 2016. Afterwards, it was assembled and the team conducted a set of initial checkouts to fully prepare the booster for its planned rollout to the launch pad designated Site LC-2. The rocket was transported to its launch site on Wednesday, June 22, after a three-hour journey.
After liftoff, the Long March 7 rocket will commence its short vertical ascent, powered by its four strap-on boosters for slightly more than three minutes until their separation. Then, the launch vehicle will be accelerated by its first stage alone for about 15 seconds, and shortly after, this stage is expected to be jettisoned. From this moment, the rocket’s second stage will take control over the flight, however its burn time isn’t exactly specified as it is still not determined whether the launch vehicle will fly in a configuration with a possible optional third stage, named YZ-1.
The upcoming mission will mark also the first liftoff from the Wenchang Satellite Launch Center constructed in November 2014. The center was selected for its low latitude, which will allow for a substantial increase in payload, necessary for the future manned programs. Due to its proximity to the equator, it can save fuel consumption during space launches. The launch site, thanks to its location on an island enables easy transportation of the large rocket components by ship and facilitates the case of rocket debris falling from the sky into the ocean instead of over populated inland areas.
The launch will be open for the public. Up to 25,000 spectators should be able to view it in person for the first time in the history of Chinese orbital launches. For this occasion, the government designated eight viewing areas.
The maiden flight of Long March 7 will be the eight orbital mission for China this year. It will be also the 230th launch of the Long March rocket series. The country’s next mission is currently scheduled for July 2016, when a Long March 2D booster is slated to send the QUantum Experiments at Space Scale (QUESS) technology demonstrator into orbit from Jiuquan Satellite Launch Center in Gansu Province. The exact date of the launch is yet to be announced.