Top of page. Skip to main contents. Skip to main menu. Skip to footer.

Main contents start here.

MHI Launch Services

Current location
MHI Launch Services Top > Launch Vehicle Family > H-IIB Launch Vehicle

H-IIB Launch Vehicle

The H-IIB launch vehicle is a heavier version compared to the H-IIA launch vehicle. The new H-IIB launch vehicle, based on the technology of the H-IIA, has achieved vastly increases in its launch capacity through enhanced rocket engine propulsion power and larger satellite fairing.

The H-IIB launch vehicle is a two-stage rocket using liquid oxygen and liquid hydrogen as propellant and has four strap-on solid rocket boosters (SRB-A).
First stage of the H-IIB has two liquid rocket engines (LE-7A) and it has four SRB-As attached to the body, while the standard version of the H-IIA has one LE-7A engine and two SRB-As. In addition, the H-IIB's first-stage has expanded to 5.2m in diameter from 4m of the H-IIA's one. The total length of the first stage has also extended by 1m from that of the H-IIA. As the result of such enhancement, the on-board propellant of the H-IIB is 1.7 times more than the H-IIA. The H-IIB has developed based on the technology and the reliability that we have cultivated in development of the H-IIA.

The H-IIB launch vehicle launches the H-II Transfer Vehicle (HTV) as one of transportation to the International Space Station (ISS).


Type H2B H2A204 (Ref)
Height 56 meters 53 meters
Gross Mass 531 metric tons
(excluding satellite mass)
443 metric tons
(excluding satellite mass)
First Stage 2 (2 LE-7As) 1 (1 LE-7A)
Second Stage 1 (1 LE-5B) 1 (1 LE-5B)
SRB-A 4 4
Launch Capacity GTO 8.0 metric tons 6.0 metric tons
Orbit for HTV 16.5 metric tons -

Each Stage

  First Stage Solid Rocket Booster
Second Stage
Propellant LH2/LOX HTPB Composite LH2/LOX
Propellant Mass 177.8 metric tons 263.8 metric tons
(for 4 SRB-As in total)
16.6 metric tons
Propulsion System LE-7A Engine - LE-5B Engine
Thrust 2,196 kN 9,220 kN 137 kN
Burning Time 352 minutes 114 minutes 499 minutes
Impulse to weight ratio 440 minutes 283.6 minutes 448 minutes
Avionics System Guidance Control Computer
Flight Termination System
Rate Gyro Package
Lateral Acceleration Sensor Unit
VHF Telemetry
Electrical Power
- Guidance Control Computer
Inertial Measurement Unit
Flight Termination System
UHF Telemetry
C-Band TrackingRange Safety Command Receiver
Electrical Power
Return to top.
Page Top

Footer menu start here.