The Pentagon and Missile Defense Agency (MDA) should reconsider any ballistic missile defense (BMD) missions focused on boost-phase systems, a recent National Research Council report says.

“The Department of Defense should not invest any more money or resources in systems for boost-phase missile defense,” says the report, “Making Sense of Ballistic Missile Defense : An Assessment of Concepts and Systems for U.S. Boost-Phase Missile Defense in Comparison to Other Alternatives,” released Sept. 11.

Noting that the Pentagon has had several start-and-stop efforts with boost-phase BMD programs, plans for such efforts keep cropping up “like a bad penny” every year, said David Montague, co-chairman of the committee that produced the report, during a press conference accompanying the study’s release.

“Boost-phase missile defense is not practical or cost-effective under real-world conditions for the foreseeable future,” the report says. “All boost-phase intercept (BPI) systems suffer from severe reach-versus-time-available constraints. This is true for kinetic kill interceptors launched from Earth’s surface, from airborne platforms, or from space. It is also true for a directed-energy (laser) weapon in the form of the airborne laser (ABL), where reach is limited by problems of propagating enough beam over long distances in the atmosphere and focusing it onto a small spot, even with full use of sophisticated adaptive optical techniques.”

However, the NRC report says, the recommendation against boost-phase focus “is not intended to preclude funding of generic research and development such as the ABL testbed, which is currently involved in boost-phase intercept, or funding of adaptive optics concepts or advances in high-power lasers that may be useful for other applications.”

While technically possible in principle, boost-phase missile defense — whether kinetic or directed energy, and whether based on land, sea, air, or in space — is not practical or feasible for any of the missions that the NRC committee looking into BMD was asked to review, the report says.

The MDA should turn greater attention toward other BMD efforts, the report says.

“The Missile Defense Agency should reinstitute an aggressive, balanced midcourse discrimination research and development effort focused on the synergy between X-band radar data and concurrent interceptor observation while closing on the threat.”

A continuing program of test and analysis should be implemented to maintain the technical capacity that will be needed to support an adequate level of discrimination as new countermeasures are developed and deployed, the report says.

“A serious effort [is needed] to gather and understand data from past and future flight tests and experiments (including flights of U.S. missiles) from the full range of sensors and to make full use of the extensive data collected from past experiments to generate robust discrimination techniques and algorithms.”

The report says, “The effort required for success in this endeavor does not need to be overlarge but does require that high-quality expertise be brought to bear. The annual budget outlay, if planned correctly, can be modest compared to current expenditures.”

The Missile Defense Agency , the report says, should strengthen its systems analysis and engineering capability in order to do a better job of assessing system performance and evaluating new initiatives before significant funding is committed. “Cost-benefit analysis should be central to that capability,” the report says.