A wider, more powerful H-II with two first-stage engines and four boosters, built to launch Kounotori, the HTV cargo ship that supplies the International Space Station. It launches all nine Kounotori missions, from 2009 to 2020.
- Launches
- 9
- Success rate
- 100%
- 0 failures
- Builder
- MHI
- Height
- 56.6 m
- Diameter
- 5.2 m
- Stages
- 2
- Boosters
- 4 × H-II SRB-A3
- Propellants
- Solid, LH2 / LOX
- Payload to LEO
- 16,500 kg
- Payload to GTO
- 8,000 kg
Launches per year
H-IIB 304
Other H-II rockets
Show as table
| Year | Launches | H-IIB 304 |
|---|---|---|
| 1994 | 2 | 0 |
| 1995 | 1 | 0 |
| 1996 | 1 | 0 |
| 1997 | 1 | 0 |
| 1998 | 1 | 0 |
| 1999 | 1 | 0 |
| 2001 | 1 | 0 |
| 2002 | 3 | 0 |
| 2003 | 2 | 0 |
| 2005 | 1 | 0 |
| 2006 | 4 | 0 |
| 2007 | 2 | 0 |
| 2008 | 1 | 0 |
| 2009 | 3 | 1 |
| 2010 | 2 | 0 |
| 2011 | 3 | 1 |
| 2012 | 2 | 1 |
| 2013 | 2 | 1 |
| 2014 | 4 | 0 |
| 2015 | 4 | 1 |
| 2016 | 3 | 1 |
| 2017 | 6 | 0 |
| 2018 | 4 | 1 |
| 2019 | 1 | 1 |
| 2020 | 4 | 1 |
| 2021 | 2 | 0 |
| 2023 | 2 | 0 |
| 2024 | 2 | 0 |
| 2025 | 1 | 0 |
H-II rockets
| Rocket | Flown | Launches | Success rate | Height | Payload to LEO |
|---|---|---|---|---|---|
| H-II | 1994 to 1999 | 7 | 71% | 49 m | 10,060 kg |
| H-IIA 202 | 2001 to 2025 | 35 | 100% | 53 m | 10,000 kg |
| H-IIA 2024 | 2002 to 2008 | 7 | 86% | 57 m | 12,500 kg |
| H-IIA 2022 | 2005 to 2007 | 3 | 100% | 53 m | 11,250 kg |
| H-IIA 204 | 2006 to 2021 | 5 | 100% | 53 m | 15,000 kg |
| H-IIB 304 | 2009 to 2020 | 9 | 100% | 56.6 m | 16,500 kg |