Realistic high frequency surface wave radar (HFSWR) targets are investigated numerically in terms of electromagnetic wave target interactions. Radar cross sections (RCS) of these targets are simulated via both the finite-difference time-domain (FDTD) method and the Method of Moments (MoM). The virtual RCS prediction tool that was introduced in previous work is used for these investigations. The virtual tool automatically creates the discrete FDTD model of the target under investigation and performs the FDTD RCS analysis. It also automatically constructs a MoM wire grid model of the target; therefore, it is also possible to compare FDTD results against the MoM-based NEC (Numerical Electromagnetic Code) data. Bi-static RCS patterns under a variety of illuminations over the whole HP band (3-30 MHz) are presented. The mono-static RCS vs. frequency of these targets is also given.