Head to head

Kosmos 11K63 vs Kuaizhou 1A

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

Kosmos 11K63: 300 kg

Kuaizhou 1A: 300 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	Kosmos 11K63	Kuaizhou 1A
Flights flown	126	31
Success rate	93.7%	90.3%
Payload to LEO (kg)	300	300
Length (m)	31	19.4
Diameter (m)	1.6	1.4
Launch mass (t)	48	30
Stages	2	4

Kosmos 11K63

Flight record

93.7% success rate118 of 126 flown · 8 failed

1965peak 1970 · 20 flights1977

Maiden flight 1966-05-24. Retired.

Kuaizhou 1A

Flight record

90.3% success rate28 of 31 flown · 3 failed

2017peak 2023 · 6 flights2025

Maiden flight 2017-01-09. Still flying.

Kosmos 11K63 is built by Strategic Rocket Forces of Russia.Kuaizhou 1A is built by ExPace of China (company profile on Space Index).

Full specifications and the complete launch history for each: Kosmos 11K63 · Kuaizhou 1A.

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