The development and application of a finite difference time-domain sol
ver for Maxwell's equations are presented. The work described here is
the result of a research effort aimed at developing an accurate and ef
ficient numerical method capable of simulating electromagnetic scatter
ing from three-dimensional arbitrarily shaped objects to predict their
radar cross sections (RCS). The finite difference formulation is pres
ented and the accuracy of the Maxwell solver is demonstrated for sever
al test eases. The capability of the Maxwell solver as a design and an
alysis tool is illustrated through a parametric study that examines th
e effects of systematic changes in the shape of aircraft wings on thei
r RCS, The results indicate that for head-on radar illumination, a sig
nificant reduction in the RCS of a wing can be achieved by sweeping it
s leading edge and varying its spanwise thickness.