  Optimal search strategies where targets are observed at several different
angles are found. Targets are assumed to exhibit rectangular symmetry and have
a uniformly-distributed orientation. By rectangular symmetry, it is meant that
one side of a target is the mirror image of its opposite side. Finding an
optimal solution is generally a hard problem. Fortunately, symmetry principles
allow analytical and intuitive solutions to be found. One such optimal search
strategy consists of choosing n angles evenly separated on the half-circle and
leads to a lower bound of the probability of not detecting targets. As no prior
knowledge of the target orientation is required, such search strategies are
also robust, a desirable feature in search and detection missions.
