The H-IIA Launch Vehicle is a new rocket developed on a basis of technical results obtained from the development of the H-II rocket. The H-IIA Launch Vehicle is designed to meet a diversity of new needs and demands in modern space transportation, including for the supplementary transports to the International Space Station and for the spacecrafts to be launched in the 21st century. This launch vehicle especially meets the current demands of lower costs while still maintaining a high degree of reliability achieved hitherto.

The standard type H-IIA (H2A202) is length of 52.5 m, diameter of 4 m, and mass of 285 ton without spacecraft mass. It consists of the first and second stages, fairing, and Solid Rocket Booster-A (SRB-A), and is the high-powered large-scale launch vehicle equipped with propellant systems using liquid hydrogen / oxygen.

The first stage consists of the high performance cryogenic LE-7A engine, the engine section, LH2 tank, the center body section, LOX tank and the interstage section. Two or four newly developed Solid Rocket Boosters (SRB-A) are attached to the first stage in order to augment the LE-7A engine thrust during an ascent phase. In the H2A202 series, two or four Solid Strap-on Boosters (SSBs) are strapped on according to customers' performance requirements.

The second stage consists of highly reliable cryogenic LE-5B engine, LH2 tank, LOX tank and the avionics systems installed on an equipment panel. The LE-5B engine has a multi-restart capability to meet various mission requirements. Attitude control is performed using reliable electromechanical actuators of the LE-5B engine and a hydrazine gas-jet reaction control system installed on the equipment panel.
Solid Rocket
Booster (SRB-A)
Solid Strap-on
Booster (SSB)
Total Vehicle
Overall Length
(m, with 4S or 5S fairing)
37.2 15.2 14.9 9.2 52.5
4 2.5 1 4 --
114 150 (2 Units) 31 (2 Units) 20 Approx. 285*
Propellant Mass
100 130 (2 Units) 26 (2 Units) 16.7 --
(in vacuum, kN)
1,098 4,511
(max, 2 Units)
(max, 2 Units)
137 --
Burning Time
390 100 60 540 --
Propellant LH2 / LOX Solid Propellant Solid Propellant LH2 / LOX --
Specific Impulse
(in vacuum, sec)
440 280 282 447 --
* not including the payload