FLUG REVUE August 2002: Japan HOPE spaceplane plans

HOPE – JAPAN'S SHUTTLE DREAM

By Matthias Gründer

The Japanese have one basic principle which they stubbornly pursue: as long as a rocket, satellite or research vehicle appears feasible within a financial framework, then it is implemented, no matter how much time is needed. This means they have all the time in the world to build up their own space infrastructure and do not have an ongoing struggle to reconcile the disparate petty national interests of multiple partners, as the Europeans do.

HOPE artists impression

But this was not always the case. First if all they were forced to adapt earlier, extremely tight timescales to reality, as the Japanese technological successes of the 1970s and 1980s were not easily transferable to space. And then, until only a few years ago there were three institutions working on separate space projects: the National Space Development Agency (NASDA), the National Aerospace Laboratory (NAL) and the Institute of Space and Astronautical Science of Tokyo University.

Research work on a national space shuttle dates back to the end of 1985, coinciding with nomination of the first Japanese astronaut candidates to fly on the US shuttle programme. The cost of building and developing an equivalent national system was estimated at the time at around $20 billion, and this was simply too much money for three projects that might be running in parallel.

In June 1986, during negotiations regarding possible co-operation representatives of these three institutions indicated their willingness to work together for the first time in Japanese space history in a challenging research field. It was agreed that NASDA would lead the project, with NAL carrying out the wind tunnel tests and ISAS responsible for the aerodynamic firing tests.

As long as sufficient financial resources were available, development work proceeded rapidly despite a number of technical setbacks. The first two firing tests of scale models of the shuttle were completed in the autumn of 1986. According to technical data published by NASDA, the future space shuttle, designated HOPE (H-II Orbiting Plane), was to be 23m long, have a 23m wingspan and a 55t take-off weight, and was to be able to transport a 15t payload into earth orbit with a crew of two or three from 1999. A more powerful version of NASDA's own H-II was to be used as the launch vehicle, but its designers encountered a whole series of difficulties.

But then, in the wake of the cutbacks in funding following the collapse of the Soviet Union and its satellite states, which affected Japanese space programmes no less than other Western space programmes, the over-ambitious HOPE plans had to be abandoned, although the goal of developing a Japanese reusable space transport system persisted.

Despite these problems, the Orbital Re-entry Experiment (OREX) re-entry vehicle was launched by the first H-II in February 1994, and two years later the Hypersonic Flight Experiment (HYFLEX) test plane was carried into space by the purpose-built J-I rocket. About a dozen tests entailing dropping the 760kg Automatic Landing Flight Experiment (ALFLEX) model from altitude were carried out in Australia from July 1996.
Between then and the middle of 2000 a number of experiments were carried out until, following a change of government, the entire project came under fire for basically lacking in technological innovation – a terrible slight in the Japanese research environment.

Since then the project has been radically overhauled and combined with two NAL projects, the Supersonic Transport (SST) and the Hypersonic Transport Propulsion System Research (HYPR) engine. Present plans are initially confined to "only” building the unmanned HOPE-X space shuttle.

Accordingly, a High-Speed Flight Demonstrator (HSFD) 16m long and with a wingspan of 9m is to be developed jointly with the French CNES space agency. This will be launched by an H-IIA and, after orbiting the earth, touch down on an airfield currently under construction on Christmas Island in the Pacific.

If the time and financial constraints can be adhered to and flights of the unmanned system are successful, it could then be developed into a platform for transporting satellites or payloads, for example, to the International Space Station, or attention could be switched to building a manned system. Given that none of the other space nations has such a capacity, this would be a worthwhile objective.

From page 42 of FLUG REVUE 8/2002

Last updated 11 July 2002

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