"Not So Fast: Comments on 'Estimates of Performance and Cost for Boost Phase Intercept' presented to the Marshall Institute’s Washington Roundtable on Science and Public Policy by Greg Canavan on 24 September 2004"
Abstract
Dr. Greg Canavan’s paper, “Estimates of Performance and Cost for Boost Phase
Intercept,” [http://www.marshall.org/article.php?id=262] examines some implications of
constellation size and interceptor cost and weight for the total costs and feasibility of a
space-based boost-phase interceptor (SBI) system. The paper argues, in general, that a
“concentrated” system, that is, one that is tailored to defend against missiles launched
from a small geographic area, can be substantially cheaper than is currently believed.
North Korea might be considered “small.” The paper states that reductions in expected
cost come about from a combination of lower estimates of SBIs mass, lower estimates of
individual satellite cost, and a constellation that requires fewer interceptors because it
covers only a restricted range of latitudes.
We believe that mass and cost estimates are wrong and the simple model of
satellite coverage exaggerates the effect of concentration. All the errors together lead to
an extreme underestimation of the cost. The paper’s SBI masses are based on unproven
and very optimistic estimates of kill vehicle masses; its per satellite costs are based on
unrealistic learning curve performance; and a more accurate model of satellite orbits
shows that the benefits of concentration are somewhat smaller than the paper’s simple
model suggests.