Progress in space technology has played a key role in pushing technological advances in the industrialized nations and producing innovative products of the era. However, until now there have been very few quantitative assessments of the pervasive economic effects of new technologies developed by national organizations such as NASDA (National Space Development Agency of Japan) . Regretfully, such effects are rather difficult to realize despite their possible benefits. We selected NASDA’s operational satellites as a case study and conducted cost breakdown of developing and launching these satellites. The calculated amount was then allocated to each industrial sector classified in the inter-industry relations table to determine the pervasive economic effects. Based on the above-mentioned calculation and others, the following results are obtained. 1)Pervasive Economic Effects by Industrial Sectors (in Amount) : To determine the total induced effect of developing and launching NASDA’s operational satellites. 2) Influence Factor: To determine the influence factor, defined as the extent of impact unit of investment by developing and launching satellites will have on each industry, to make a comparison with other industries.

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This paper discusses the concept of constructing inexpensive Solar Power Satellites (SPS) which has the following characteristics; (1) deployable structure, (2) utilization of centrifugal force, (3) no Extra Vehicular Activity (EVA) nor robot, (4) attitude control by natural forces like solar wind and/or magnetic field. Several ideas are evaluated and described.

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The technology of the energy transmission using microwave is very useful in space as well as on the ground. We are preparing a rocket experiment (METS: Microwave Energy Transmission in Space) and its preparatory airplane experiment called MILAX (Microwave Lifted Aircraft eXperiment) in the International Space Year. The objectives of the METS are to verify a newly developed microwave energy transmission system in space and to study nonlinear effects of the microwave energy beam in the space plasma environment. We will also perform a ground-based energy transmission test of the developed system by using a small airplane as a target before the launch. The transmission test in the radio anechoic chamber showed that the transmission system developed for the MILAX can transmit enough power and accurately control the microwave beam.

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“A space fuel station” is a promising new element of the future space transportation system. With this facility, some novel transportation schemes will be possible, which assume reusable space based orbital transfer vehicles (OTVs), and the separate launch of payloads, OTVs and fuel. Enhancement of vehicle capability, improvement of transportation flexibility and reduction of launch load can be expected in these new schemes. These will reduce the transportation costs for large future transportation demands. This paper analyzes a novel transportation system based on such fuel stations, named OTV Network, as a integrated transportation infrastructure for Earth orbital, lunar and interplanetary missions. Cost analysis indicates that OTV Network is more cost-effective than the conventional system in a large demand environment , especially where many interplanetary or retrieval missions exist. Factors which have large effects on the total system cost are identified. The features of the system and some technical issues involved in realizing them are also discussed.

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The Institute of Space and Astronautical Science (ISAS) has been engaged in the development study on the Air Turbo Ramjet (ATR) engine since 1986 in cooperation with the Ishikawajima Harima Heavy Industries Co., Ltd.(IHI) The ATR is one of the most preferable candidate for the propulsion system of a future space plane. ATR is the combined cycle engine performing like a turbojet engine at subsonic flight and a fan-boosted ramjet at supersonic and hypersonic flight below Mach 6. The advantage feature of ATR engine is that the turbine inlet temperature is decoupled from the incoming air temperature which increases as the flight Mach number increases, thus ATR cycle does not reduce thrust capability due to the turbine material limits on the hypersonic flight. Our ATR engine system was named “ATREX” after employing the expander cycle. The ATREX is energized by thermal energy extracted regeneratively in both the precooler installed in air intake and the heat exchanger in combustion chamber. The ATREX works in the flight condition from sea level static up to Mach 6 at 35 km altitude. The ATREX employs the tip turbine configuration for compactness of turbo machinery. We have tested the ATREX system at the sea level static condition using the 1/4-scale model (ATREX-500) with fan inlet diameter of 300 mm and overall length of 2,200 mm. The present paper addresses the analysis of the Air-Turbo Ramjet (ATR) Engine to be applied for the TSTO Space Plane and the test results of the ATREX engine at sea level static condition.

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