Head to head

Soyuz 2.1b/Fregat vs Soyuz-U-PVB

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

Soyuz 2.1b/Fregat: 8,200 kg

Soyuz-U-PVB: 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	Soyuz 2.1b/Fregat	Soyuz-U-PVB
Flights flown	26	74
Success rate	92.3%	97.3%
Payload to LEO (kg)	8,200	6,900
Length (m)	46.3	51
Diameter (m)	2.95	3
Launch mass (t)	312	313
Stages	4	2

Soyuz 2.1b/Fregat

Flight record

92.3% success rate24 of 26 flown · 2 failed

2006peak 2011 · 4 flights2026

Maiden flight 2006-12-27. Still flying.

Soyuz-U-PVB

Flight record

97.3% success rate72 of 74 flown · 2 failed

1984peak 1999 · 9 flights2009

Maiden flight 1984-03-21. Retired.

Soyuz 2.1b/Fregat is built by Progress Rocket Space Center of Russia.Soyuz-U-PVB is built by Progress Rocket Space Center of Russia.

Full specifications and the complete launch history for each: Soyuz 2.1b/Fregat · Soyuz-U-PVB.

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