Japan-U.S. Cooperation in Equipment and Technology

(Excerpts from Defense of Japan)

The Japan-U.S. Security Treaty calls on the two countries to cooperate with each other in maintaining and developing their respective defense capabilities. The "Mutual Defense Assistance Agreement between Japan and the United States" provides the framework for mutual cooperation in the area of defense between the two countries. It goes without saying that Japan, acting on the principle of mutual cooperation stipulated in these agreements, should positively promote cooperation with the U.S. in equipment and technology aspects, while recognizing the importance of maintaining the nation's technological and production bases.

In 1983, Japan, in view of the climate of improvement in its technological level, decided to open the way for the transfer of its military technology to the U.S. as an exception to the Three Principles of Arms Exports, etc. (see Reference a). In accordance with this decision, Japan has since decided to transfer, to the U.S., technology related to portable SAMs, technology for the construction and remodeling of U.S. naval vessels, technology related to the next generation support fighter (FS-X), technology for the Digital Flight Control System (DFCS) to be installed on P-3C anti-submarine patrol aircraft, and technology related to joint research on a ducted rocket engine.

The F-2 support fighter which performed its first test flight in October 1995, as the first test case of joint research and development of equipment by the two countries. Joint R&D efforts are important not only for effectively developing equipment by the synergy of their superb technologies but also from the viewpoint of promoting defense cooperation between the two countries.

Japan and the U.S. have regularly held the bilateral Systems and Technology Forum (S&TF) to enhance cooperation on defense-related technologies between the two countries. The two countries are steadily implementing joint research on a ducted rocket engine on the basis of the arrangements concluded in September 1992, and also started joint research on advanced steel technology and fighting vehicle propulsion technology using ceramic material after the conclusion of the arrangements in October 1995. The two countries are actively promoting prospective joint research on such projects as eye-safe laser. (see References b and c)

Reference a. Statement of Chief Cabinet Secretary on Transfer of Military Technologies to the United States

January 14, 1983

Since June 1981, the Japanese Government has received requests from the U.S. Government fro exchange of defense-related technologies. After careful studies on the transfer to the U.S. of "military technologies" as a part of such exchange, the Japanese Government has reached the following conclusion, which was approved by the Cabinet today:

  1. Under the Japan-U.S. security arrangement, the U.S. and Japan, in cooperation with each other, are to maintain and develop their respective capacities to resist armed attack. In improving its defense capacities, Japan has been benefiting from various kinds of cooperation extended by the U.S., including transfer of U.S. technologies to Japan. In view of the new situation which has been brought about by, among other things, the recent advance of technology in Japan, it has become extremely important for Japan to reciprocate in the exchange of defense related technologies in order to ensure the effective operation of the Japan-U.S. Security Treaty and its related arrangements, which provide for and envisage mutual cooperation between Japan and the U.S. in the field of defense, and contribute to peace and security of Japan and in the Far East.

  2. The Japanese Government has so far dealt with the question of arms export (including transfer of "military technologies") in accordance with the Three Principles on Arms Export and the Government Policy Guideline on Arms Export. In view of the foregoing, however, the Japanese Government has decided to respond positively to the U.S. request for exchange of defense-related technologies and to open a way for the transfer to the U.S. of "military technologies" (including arms which are necessary to make such transfer effective) as a part of the technology exchange with the U.S. mentioned above; such transfer of "military technologies" will not be subject to the Three Principles on Arms Export. The implementation of such transfer will be made within the framework of the relevant provisions of the MDA Agreement. In this manner, the fundamental objective of refraining from aggravating international disputes, which Japan upholds as a nation committed to peace and on which the Three Principles are based, will be secured.

  3. The Japanese Government will continue to maintain, basically, the Three Principles on Arms Export and to respect the spirit of the Diet Resolution on arms export adopted in March 1981.


Reference b. Global Partnership Plan of Action (Part I)

(January 9, 1992, Tokyo)


II. Political and Security Relations

*Continue a close dialogue to ensure the smooth and efficient stationing of U.S. forces in Japan, recognizing that it is important for the U.S. to maintain capable forward deployed military forces at an appropriate level in the region.

*Hold the first security consultative meeting at the earliest opportunity of the Minister for Foreign Affairs and Minister of State, Director-General of the Defense Agency on the Japanese side, and Secretary of State and Secretary of Defense on the U.S. side.

*Promote interoperability, recognizing that complementary defense cooperation is a significant aspect of the bilateral security relationship.

*Enhance defense cooperation, including:
-Conclude agreement on joint research on the ducted rocket engine, and continue examination of defense technology fields such as fighting vehicle propulsion technology using ceramic materials, millimeter wave/infrared dual mode seekers, closed-loop degaussing for steel-hull ships, and advanced steel for ships and armored vehicles, under the Japan-U.S. Mutual Defense Assistance Agreement.
-Promote further two-way transfer of defense related technology.
-Reaffirm the importance of strengthening early warning and surveillance capabilities. Japan's five year Mid-Term Defense Program states that it will require four early warning and control aircraft. Japan will continue to study availability and appropriateness of various aircraft including a new type of AWACS, and the U.S. will assist in this effort.

Reference c. Candidate for the Japan-U.S. Joint Research

Ducted rocket engine

-Supersonic rocket engine technology which includes secondary combustion by adding outside air to the fuel rich exhaust gas from primary combustion of solid fuel. (Joint research was started with the conclusion of an agreement on joint research between the two governments on Sept. 29, 1992.)

Millimeter wave/infrared dual mode seekers

-Missile seeker technology with the simultaneous use of millimeter wave and infrared which enables the fused signal processing for better target detection.

Closed-loop degaussing for steel-hull ships

-Technology to automatically monitor and reduce the magnetic signature of a steel-hull ship using on-board sensors and coils.

Fighting vehicle propulsion technology using ceramic materials

-Technology of low heat rejection diesel engines adopting ceramic coating and ceramic components, for use on tanks and armored vehicles. (Joint research was started with the conclusion of an agreement on joint research between the two governments on Oct. 31, 1995.)

Advanced steel technology

-Technology relating to welding of high strength steels to be used for naval vessel structures. (Joint research was started with the conclusion of an agreement on joint research between the two governments on Oct. 31, 1995.)

Eye-safe laser

-Ordinary laser beam is injurious to the eye, but this is the technology of generating long-wave length, low-output laser beam that would not harm the eye.

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