Head to head

Atlas IIAS vs Soyuz U

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 IIAS: 6,580 kg

Soyuz U: 6,900 kg

Side by side

7 comparable figures

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

Metric	Atlas IIAS	Soyuz U
Flights flown	30	714
Success rate	100%	97.2%
Payload to LEO (kg)	6,580	6,900
Length (m)	47.54	51.1
Diameter (m)	3.04	2.95
Launch mass (t)	204	313
Stages	3	3

Atlas IIAS

Flight record

100% success rate30 of 30 flown

1993peak 1997 · 5 flights2004

Maiden flight 1993-12-16. Retired.

Soyuz U

Flight record

97.2% success rate694 of 714 flown · 20 failed

1973peak 1979 · 47 flights2017

Maiden flight 1973-05-18. Retired.

Atlas IIAS is built by Lockheed Martin of the United States (company profile on Space Index).Soyuz U is built by Russian Federal Space Agency (ROSCOSMOS) of Russia.

Full specifications and the complete launch history for each: Atlas IIAS · Soyuz U.

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