Head to head

Atlas V 551 vs H-IIA

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

H-IIA: 10,000 kg

Side by side

11 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	H-IIA
Flights flown	23	50
Success rate	100%	98%
Payload to LEO (kg)	18,850	10,000
Payload to GTO (kg)	8,890	4,100
Launch cost	$153M	$90M
Cost per kg to LEO	$8,117	$9,000
Liftoff thrust (kN)	12,269	2,260
Length (m)	59.7	53
Diameter (m)	3.8	4
Launch mass (t)	573	285
Stages	2	2

Atlas V 551

Flight record

100% success rate23 of 23 flown

2006peak 2025 · 5 flights2026

Maiden flight 2006-01-19. Retired.

H-IIA

Flight record

98% success rate49 of 50 flown · 1 failed

2001peak 2017 · 6 flights2025

Maiden flight 2001-08-29. Retired.

Atlas V 551 is built by United Launch Alliance of the United States (company profile on Space Index).H-IIA is built by Mitsubishi Heavy Industries of Japan (company profile on Space Index).

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

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