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 The , or NASDA, was a Japanese national space agency established on October 1, 1969 under the National Space Development Agency Law only for peaceful purposes. Based on the Space Development Program enacted by the Minister of Education, Culture ...

in order to give Japan a capability to launch larger

satellite A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scient ...

s in the 1990s. It was the first two-stage liquid-fuelled rocket Japan made using only technologies developed domestically. It was superseded by the

H-IIA H-IIA (H-2A) is an active expendable launch system operated by Mitsubishi Heavy Industries (MHI) for the Japan Aerospace Exploration Agency. These liquid fuel rockets have been used to launch satellites into geostationary orbit; lunar orbi ...

rocket following reliability and cost issues.

Background

Prior to H-II, NASDA had to use components licensed by the United States in its rockets. In particular, crucial technologies of H-I and its predecessors were from the

Delta rocket The Delta rocket family was a versatile range of American rocket-powered expendable launch systems that provided space launch capability in the United States from 1960 to 2024. Japan also launched license-built derivatives (N-I (rocket), N-I, N ...

s (the manufacturer of the Delta rockets,

McDonnell Douglas McDonnell Douglas Corporation was a major American Aerospace manufacturer, aerospace manufacturing corporation and defense contractor, formed by the merger of McDonnell Aircraft and the Douglas Aircraft Company in 1967. Between then and its own ...

, later

Boeing The Boeing Company, or simply Boeing (), is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, and missiles worldwide. The company also provides leasing and product support s ...

and the United Launch Alliance, would later use the H-IIA's technologies (the rocket itself is the successor to the H-II) to create the Delta III, albeit short lived). Although the H-I did have some domestically produced components, such as LE-5 engine on the second stage and

inertial guidance system An inertial navigation system (INS; also inertial guidance system, inertial instrument) is a navigation device that uses motion sensors (accelerometers), rotation sensors ( gyroscopes) and a computer to continuously calculate by dead reckoning ...

, the most crucial part, the first stage engine, was a licence-built version of the Thor-ELT of the US. By developing the LE-7 liquid-fuel engine and the solid booster rockets for the first stage, all stages of H-II had become "domestically developed". The H-II was developed under the following policies, according to a NASDA press release: #Develop the launch vehicle with Japanese space technology. #Reduce both development period and costs by utilizing developed technologies as much as possible. #Develop a vehicle which can be launched from the existing Tanegashima Space Center. #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. The H-II was new, incorporating larger LH₂/LOX tanks, and a new upper stage, consisting of a cylindrical LH₂ tank with a capsule-shaped LOX tank. The LH₂ tank cylinder carried payload launch loads, while the LOX tank and engine were suspended below within the rocket's inter-stage. The second stage was powered by a single LE-5A engine.

History

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. The Rocket Systems Corporation (RSC), a consortium of 74 companies including

Mitsubishi Heavy Industries is a Japanese Multinational corporation, multinational engineering, electrical equipment and electronics corporation headquartered in Tokyo, Japan. MHI is one of the core companies of the Mitsubishi Group and its automobile division is the prede ...

Nissan Motors is a Japanese multinational automobile manufacturer headquartered in Yokohama, Kanagawa, Japan. The company sells its vehicles under the ''Nissan'' and '' Infiniti'' brands, and formerly the ''Datsun'' brand, with in-house performance tuning ...

, and

NEC is a Japanese multinational information technology and electronics corporation, headquartered at the NEC Supertower in Minato, Tokyo, Japan. It provides IT and network solutions, including cloud computing, artificial intelligence (AI), Inte ...

, was established in 1990 to manage launch operations after the rockets' completion. In 1992, it had 33 employees. 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 (US$190 million), too expensive compared to international competitors like Ariane. (This is in part due to the

Plaza Accord The Plaza Accord was a joint agreement signed on September 22, 1985, at the Plaza Hotel in New York City, between France, West Germany, Japan, the United Kingdom, and the United States, to depreciate the U.S. dollar in relation to the French ...

's changes to the exchange rate, 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

rockets started in order to minimize launch costs. In 1996, RSC signed a contract with the Hughes Space and Communications Group to launch 10 satellites. The successive failure of flight 5 in 1998 and flight 8 in the following year brought an end to the H-II series and the contract with Hughes. 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.

Launch history

Gallery

Image:H-II-GTV.jpg, The Ground Test Vehicle of H-II, now installed at

Tsukuba Space Center The Tsukuba Space Center (TKSC) also known by its radio Call sign, callsign Tsukuba, is the operations facility and headquarters for the Japan Aerospace Exploration Agency (JAXA) located in Tsukuba Science City in Ibaraki Prefecture. The facil ...

. Image:H-II_F7_02.JPG, The first and second stages of the canceled Flight 7, at a hangar in Tanegashima Space Center.

References

External links