The relatively compact missile is designed for attacking small- to medium-size warships (e.g., frigates, corvettes and destroyers), although multiple hits are effective against larger vessels, such as aircraft carriers. It is guided inertially in mid-flight and turns on active radar late in its flight to find and hit its target. As a countermeasure against air defence around the target, it maintains a very low altitude during ingress, staying one to two meters above the sea surface. Due to the effect of the radar horizon, this means that the target may not detect an incoming attack until the missile is only 6,000 m from impact. This leaves little time for reaction and stimulated the design of close-in weapon systems (CIWS).