31.08.2022

HELSINKI — China’s main space contractor plans to revamp a highly successful, 30-year-old Long March rocket model to adapt to the trend towards reusability in the launch sector. 

The 63rd and latest Long March 2D lifted off from the fog-shrouded Taiyuan Satellite Launch Center, north China, late on Aug. 23 Eastern time, with insulation tiles falling from the payload fairing as the rocket rose into the sky.

The two-stage, hypergolic rocket—with its record blemished only by a single partial failure in December 2016—successfully inserted the Beijing-3B satellite into a sun-synchronous orbit.

The rocket has in recent years launched from all three of China’s inland spaceports, providing China with a level of reliability and flexibility for launches of up to 3,500 and 1,300 kilograms to low Earth orbit and SSO respectively. 

Despite this success the China Aerospace Science and Technology Corporation (CASC) and its subsidiary, the Shanghai Academy of Spaceflight Technology (SAST) are looking to greatly change and improve the rocket, according to a report from official industry newspaper China Space News Aug. 24.

Both stages of the Long March 2D use dinitrogen tetroxide and unsymmetrical dimethylhydrazine, a highly toxic and corrosive bipropellant mix that poses risks and costs both for launch preparation and recovery of spent stages downrange.

CASC states that the rocket will in the future be upgraded to use engines powered by kerosene and liquid oxygen, replacing the hypergolic YF-21C and YF-24C engines currently in use.

The news report did not state which specific engines would power the kerolox version of the Long March 2D, nor their configuration. China developed YF-100 kerolox engines for its new generation Long March 5-8 series rockets, which have debuted within the last 10 years. 

CASC is also working on uprated YF-100K engines which will notably power its new-generation crewed rocket. Tan Xuejun, the commander-in-chief of the Long March 2D, was quoted as saying the engines would also provide greater thrust.

In an earlier step towards reusability the Long March 2D was fitted with grid fins for the first time in October last year for the launch of the Chinese H-alpha Solar Explorer.

The grid fins have also been tested on the Long March 2C rocket. Their use helps constrain the area within which spent first stages fall. Spent stages from rockets launched from China’s inland spaceports have frequently caused issues downrange, and require evacuations of inhabited areas, depending on expected drop zones.

A reusable Long March 2D and ditching hypergolic fuels could cut launch costs, Tan said.

The move appears to be part of a long term plan to develop reusable space transportation systems.

SAST has previously stated it was working on a reusable version of the Long March 6 rocket. CASC’s other main rocket maker, the China Academy of Launch Vehicle Technology, is developing the Long March 8 for reusability, while also stating its super heavy-lift crew and Long March 9 launchers will eventually be made reusable. 

Landspace, a privately-backed Beijing launch startup, last week stated it successfully tested an upgraded version of its Tianque-12 methane-liquid oxygen engine which will make the first stage of its Zhuque-2 rocket reusable.

CALT’s orbital spaceplane is currently nearly four weeks into its second mission, while the suborbital spaceplane segment of the two-stage reusable space transportation system had its short and similarly clandestine second flight last week.

Quelle: SN