Long March 3B

Long March 3B

The Long March 3B (also written as CZ-3B) is a Chinese expendable orbital launch vehicle developed and operated by the China Academy of Launch Vehicle Technology (CALT), a subsidiary of the China Aerospace Science and Technology Corporation (CASC). It serves as one of China's primary heavy-lift rockets for delivering payloads to geostationary transfer orbit (GTO) and is a cornerstone of the country's commercial and national launch programs.

Design and Capability

The Long March 3B is a three-stage rocket augmented by four liquid-fueled strap-on boosters, giving it substantially more lift capacity than its predecessor, the Long March 3A. Standing 54.8 meters tall with a core diameter of 3.35 meters, the vehicle is capable of delivering up to 11,500 kg to low Earth orbit (LEO) and 5,100 kg to GTO. Its upper stage uses cryogenic liquid hydrogen and liquid oxygen propellants, a technology that has distinguished the Long March 3 family within China's launch fleet. An enhanced variant, the Long March 3B/E (Extended), features enlarged strap-on boosters for increased GTO performance.

Launches are conducted primarily from the Xichang Satellite Launch Center in Sichuan province, a facility purpose-built for geosynchronous missions owing to its relatively low latitude.

History and Operations

The Long March 3B made its first flight in 1996, an inauspicious debut that ended in a catastrophic failure shortly after liftoff. The vehicle subsequently recovered to become a reliable workhorse, accumulating a strong track record across commercial and government missions over the following decades.

Our tracking data covers 24 flights of the Long March 3B between 1996 and 2023, of which 21 were fully successful and 3 resulted in failure or partial failure. This represents a success rate broadly consistent with the vehicle's reputation as a mature, capable platform, while acknowledging that its early difficulties and a small number of later anomalies have contributed to its mixed overall record.

Notable Missions

The Long March 3B has been instrumental in building China's Beidou Navigation Satellite System, delivering multiple Beidou-3 geostationary satellites — including Beidou-3 G2, G3, and G4 — to their operational orbits. It has also lofted meteorological satellites such as the Fengyun-4B, which supports weather forecasting and disaster monitoring across the Asia-Pacific region.

Beyond national programs, the rocket has carried commercial communications satellites for international customers. The Nusantara Dua mission for Indonesia and the TJS-5 (Tongxin Jishu Shiyan) satellite demonstrate the vehicle's dual role serving both foreign operators and China's own strategic communications interests.

Legacy

The Long March 3B occupies a central place in Chinese launch history as the country's leading GTO-class vehicle for nearly three decades. While newer rockets — including members of the Long March 5 family — are beginning to assume heavier missions, the 3B continues to fly regularly and remains a primary delivery vehicle for China's navigation, meteorological, and communications satellite infrastructure.