Foreign Relations of the United States, 1981–1988, Volume XLIV, Part 1, National Security Policy, 1985–1988

98. Memorandum From the Special Advisor to the President and Secretary of State on Arms Control Matters (Nitze) to Secretary of State Shultz¹

Washington, January 30, 1986

SUBJECT

• Kinetic Energy Weapons Experiment

I was briefed today on the SDI Kinetic Energy Experiment scheduled for mid-August. The briefing team included Michael Rendine and Pete Engstrom from the SDI Organization and Lee Minichiello from Larry Woodruff’s staff.

It seems clear that this test does not require movement from the narrow to the broader interpretation of the ABM Treaty.

The project, code named Vector Sum, involves the use of mostly “off the shelf” hardware in carrying out the experiment, the basic objective of which is to reduce ambiguities in many areas of SDI technology from 103 to about 10. A Delta booster will be used to launch from Cape Canaveral two payloads into separate orbits 120 miles up and about 120 miles apart. One payload will be a target package, the other a sensor package with a slightly modified Navy Phoenix air to air radar and missile as the interceptor. After the payloads are in their orbits on their first pass over the U.S., a solid fuel Aries instrumentation rocket will be sent aloft from White Sands for certain observations; this rocket falls back to the range after sensings are taken. At a point on the next orbit the interceptor is guided to intercept the target package; the experiment could not work without the “cooperation” of the target in the form of a beacon and a large corner reflector.

The entire experiment is deemed not to involve the ABM Treaty, primarily because no part of the experiment consists of an ABM component or device capable of substituting for such component, and nothing is tested in an ABM mode. More importantly, there is no capability against a ballistic missile RV because the relative engagement velocity of this interceptor is less than 3 kilometers per second, below that required for capability against a ballistic missile RV. Additionally, the “cooperative” target in its travel must not deviate more than one degree from a straight line. The point of this is to ensure the experiment stays within the capabilities of the Phoenix radar and other sensors. A related point is that the kinetic energy vehicle is not deemed to fall into the category of “other physical principles” within the meaning of Agreed Statement D; it is based on technology which existed even prior to beginning the negotiations of the ABM Treaty.

While deemed not to be within the purview of the ABM Treaty, it could be termed an ASAT or ASAT defense weapon. It could therefore be of interest to those on the Hill who would cut off funds for tests of ASAT weapons. The current law precluding tests of ASAT weapons against an object in space applies only to the F–15 MHV program according to Defense lawyers, Abe Sofaer and Tom Graham. Some senior key staffers have been briefed on the program.

Some added points:

— The scheduled test was not included in the SDI report of last March; it was not anticipated. It will be included in the new draft annual report to be distributed by Defense in the next few weeks.

— After the upcoming test, nothing further is planned at present. SDIO is thinking of other tests but at much slower velocities (less than 1 kilometer per second) depending on the outcome of the current test; this would likely be some years away in any event.

1. Source: Department of State, Ambassador Nitze’s Personal Files 1953, 1972–1989, Lot 90D397, 1986. Top Secret; Sensitive. A stamped notation indicates Shultz saw the memorandum. McKinley initialed the memorandum and wrote: “31/1.”