Long March (rocket family)

History

China became the fifth country to independently launch a satellite when its Long March 1 rocket placed Dong Fang Hong 1 into low Earth orbit on 24 April 1970. The Long March 1 was based on the DF-4, a two-stage intermediate-range ballistic missile, while the later Long March 2, 3, and 4 families evolved from the two-stage intercontinental ballistic missile DF-5. Early performance was uneven, and the rockets were mainly used for Chinese satellites.

Over time, the needs of space launchers and strategic missiles diverged: launch vehicles focus on carrying as much payload as possible, whereas missiles must launch quickly and survive a first strike. This split is evident in newer Long March rockets, which use cryogenic fuels, unlike modern strategic missiles that are mobile and solid-fueled. The Long March 5 family is an entirely fresh design, while the Long March 6 and 7 are derived from its liquid rocket boosters to create smaller and medium-capacity launchers.

After the 1986 destruction of the U.S. Space Shuttle Challenger, a commercial launch backlog opened the door for China. In September 1988, President Ronald Reagan allowed U.S. satellites to fly on Chinese rockets, a policy that continued through 1998 with more than twenty approvals. The first foreign payload launched by China was AsiaSat 1, a satellite originally sent up by the Space Shuttle and later retrieved after a failure; it lifted off on a Long March 3 in 1990.

Propellants

The Long March 1 used nitric acid and unsymmetrical dimethylhydrazine (UDMH) in its first and second stages, with a spin-stabilized solid rocket upper stage. Long March 2, 3, and 4 main stages and liquid rocket boosters use dinitrogen tetroxide (N2O4) as oxidizer and UDMH as fuel; the third stages of Long March 3 rockets use YF-73 and YF-75 engines burning liquid hydrogen and liquid oxygen. The new generation (Long March 5, 6, 7, 8, and 10) use non-toxic LOX/kerosene and LOX/LH2 propellants, though some upper stages still use UDMH/N2O4. Long March 9 is being developed as a methalox (LOX/CH4) rocket, Long March 11 is solid-fuel, and Long March 12 uses LOX/kerosene for its first two stages.

Members

The Long March rockets are organized into series: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12. Long March 5, 6, and 7 are a newer generation sharing the 1200 kN class YF-100 engine burning RP-1/LOX, unlike earlier series using N2O4/UDMH. Long March 5 is a heavy-lift vehicle (25,000 kg to LEO), Long March 6 is small-lift (1,500 kg to LEO), and Long March 7 is medium-lift (14,000 kg to LEO).

Long March 10 and 12 use the uprated YF-100K engines. Long March 10A is a partially-reusable crewed-rated rocket for LEO missions under development; Long March 9 is initially designed to be partially reusable before becoming fully reusable. Long March 8 is geared toward Sun-synchronous orbit launches, first launched on 22 December 2020; its second flight on 27 February 2022 sent a national record of 22 satellites into SSO.

Commercial launch services

China markets launch services through the China Aerospace Science and Technology Corporation (China Great Wall Industry Corporation). After the United States stopped issuing export licenses for launches on Chinese vehicles in the mid-1990s, Thales Alenia Space built the Chinasat-6B satellite with no U.S. components, allowing launch on a Long March 3B on 5 July 2007 without violating ITAR restrictions. A Chinese Long March 2D launched Venezuela's VRSS-1 satellite on 29 September 2012.

Did You Know?

• On 5 June 2019, China launched a Long March 11 rocket from a mobile launch platform in the Yellow Sea.
• The Shenzhou spacecraft and Chang'e lunar orbiters are launched on the Long March rocket.
• Long March rockets typically launch commercial satellites from Xichang and Wenchang, military and crewed craft from Jiuquan, and Sun-synchronous satellites from Taiyuan.