H-II Transfer Vehicle


The H-II (H2) rocket was a Japanese satellite launch system, which flew seven times between 1994 and 1999, with five successes. It was developed by NASDA in order to give Japan a capability to launch larger satellites of the 1990s. It was the first rocket Japan made using only technologies developed domestically. It was superseded by the H-IIA following reliability and cost issues.


Prior to H-II, NASDA had to use components licensed by the United States in its rockets. In particular, crucial technologies of the H-I and its predecessors were from the Delta rockets. The H-I did have domestically produced components, such as the LE-5 engine on the second stage and the inertial guidance system. H-II added to this by domestically developing the LE-7 liquid-fuel engine of the first stage and the solid booster rockets.

The H-II was developed under the following policies, according to a NASDA press release:

  1. Develop the launch vehicle with Japanese space technology.
  2. Reduce both development period and costs by utilizing developed technologies as much as possible.
  3. Develop a vehicle which can be launched from the existing Tanegashima Space Center.
  4. Use design criteria which allows sufficient performance for both the main systems and subsystems. Ensure that development will be carried out properly, and safety is taken into account.


Development of the LE-7 engine which started in 1984 was not without hardships, and a worker died in an accidental explosion. The first engine was completed in 1994, two years behind the original schedule. In 1990, Rocket System Corporation was established to operate the launch missions after the rockets' completion.

In 1994, NASDA succeeded in launching the first H-II rocket, and succeeded in five launches by 1997. However, each launch cost 19 billion yen (190 million USD), too expensive compared to international competitors like Ariane. (This is in part due to the changes in exchange rates, which was 240 yen to a dollar when the project planning started in 1982, but had changed to 100 yen a dollar by 1994.) Development of the next-generation H-IIA rockets started in order to minimize launch costs.

The successive failure of flight 5 in 1998 and flight 8 in the following year brought an end to the H-II series. To investigate the cause of the failure and to direct resources into the H-IIA, NASDA cancelled flight 7 (which was to be launched after F8 due to changes in schedule), and terminated the H-II series.

H-II flights

Flight Date Payload nickname Payload Orbit Result
TF1 (Test Flight) February 4, 1994 Ryūsei OREX (Orbital Re-entry Experiment) LEO Success
Myōjō VEP (Vehicle Evaluation Payload) GTO
TF2 August 28, 1994 Kiku 6 ETS-VI (Engineering Test Satellite-VI) GEO Success
TF3 March 18, 1995 Himawari 5 GMS-5 (Geostationary Meteorological Satellite-5) GEO Success
SFU (Space Flyer Unit) LEO
F4 August 17, 1996 Midori ADEOS (Advanced Earth Observing Satellite) LEO Success
Fuji 3 Fuji OSCAR 29, JAS-2 LEO
F6 November 27, 1997 TRMM (Tropical Rainfall Measuring Mission) LEO Success
Kiku 7 (Orihime & Hikoboshi) ETS-VII (Engineering Test Satellite-VII) LEO
F5 February 21, 1998 Kakehashi COMETS (Communications and Broadcasting Engineering Test Satellites) GEO Failed to reach desired orbit
F8 November 15, 1999 MTSAT (Multi-functional Transport Satellite) GEO Engine malfunction, self-destructed
F7 Canceled Midori II ADEOS-II (Advanced Earth Observing Satellite II) Canceled



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