Head to head

Long March 4B vs Soyuz 2.1b

Two vehicles in the same payload class. Every figure below comes from the same two sources for both rockets, and a row appears only when both publish the input.

Payload to low Earth orbit

Relative

Long March 4B: 4,200 kg

Soyuz 2.1b: 8,200 kg

Side by side

8 comparable figures

The highlighted value wins the row. Rows where neither direction is better, like length or stage count, highlight nothing.

Metric	Long March 4B	Soyuz 2.1b
Flights flown	58	25
Success rate	98.3%	100%
Payload to LEO (kg)	4,200	8,200
Payload to GTO (kg)	1,500	3,250
Length (m)	44.1	46.3
Diameter (m)	3.35	2.95
Launch mass (t)	249	312
Stages	3	3

Long March 4B

Flight record

98.3% success rate57 of 58 flown · 1 failed

1999peak 2020 · 5 flights2026

Maiden flight 1999-05-10. Still flying.

Soyuz 2.1b

Flight record

100% success rate25 of 25 flown

2008peak 2021 · 4 flights2026

Maiden flight 2008-07-26. Still flying.

Long March 4B is built by China Aerospace Science and Technology Corporation of China.Soyuz 2.1b is built by Progress Rocket Space Center of Russia (company profile on Space Index).

Full specifications and the complete launch history for each: Long March 4B · Soyuz 2.1b.

Specifications from Launch Library 2 by The Space Devs, launch records from Space Index. Derived figures are computed here; see sources and method.