The H-IIB is a family of liquid-fuelled rockets providing an expendable launch system for the main purpose of launching the H-II Transfer Vehicle (HTV) towards the International Space Station. It is manufactured by Mitsubishi and JAXA. Launches will occur at the Tanegashima Space Center.
The H-IIB, will be launched for the first time in 2009 and will be able to carry a payload of up to 8 tons to GTO, compared with the payload of 4 to 6 tons for the H-IIA. Its performance in LEO will be sufficient for the HTV(16,500 kg).
The H-IIB is a derivative of the earlier H-IIA rocket. The H-IIB will have two LE-7A engines, a wide body (5.2m), external tanks on new first stage, and four SRB-A booster rockets. Second stage specification is same as H-IIA includes LE-5B engine, except new longer 5S-H type fairing for JAXA's HTV payload.
The development of this new launcher has required since 2004 a budget of around 20 billion yen (US$180 million; €150 million).