Kinetic Killer A replica of a Homing Overlay Experiment (HOE), a kinetic kill vehicle developed for SDI. The sweeping arms are supposed to increase the cross-section of the interceptor. I don't know -- looks pretty, but does not inspire great confidence. But then, that sums up the whole of SDI. At the Udvar-Hazy Air and Space Center. Wiki: http://en.wikipedia.org/wiki/Strategic_Defense_Initiative#Homing_Overlay_Experiment_.28HOE.29