Head to head

Atlas V 551 vs Zenit-2

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

Atlas V 551: 18,850 kg

Zenit-2: 13,740 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	Atlas V 551	Zenit-2
Flights flown	23	35
Success rate	100%	82.9%
Payload to LEO (kg)	18,850	13,740
Liftoff thrust (kN)	12,269	7,300
Length (m)	59.7	57
Diameter (m)	3.8	3.9
Launch mass (t)	573	459
Stages	2	2

Atlas V 551

Flight record

100% success rate23 of 23 flown

2006peak 2025 · 5 flights2026

Maiden flight 2006-01-19. Retired.

Zenit-2

Flight record

82.9% success rate29 of 35 flown · 6 failed

1985peak 1987 · 5 flights2004

Maiden flight 1985-04-13. Retired.

Atlas V 551 is built by United Launch Alliance of the United States (company profile on Space Index).Zenit-2 is built by Yuzhnoye Design Bureau of Ukraine.

Full specifications and the complete launch history for each: Atlas V 551 · Zenit-2.

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