  This experimental study reports on the behavior of a filament attached to the
rear of a three- dimensional cylinder. The axis of the cylinder is placed
normal to a uniform incoming flow and the filament is free to move in the
cylinder wake. The mean position of the filament is studied as a function of
the filament length L. It is found that for long (L/D > 6.5, where D is the
cylinder diameter) and short (L/D < 2) filaments the mean position of the
filament tends to align with the incoming flow, whereas for intermediate
filament lengths (2 < L/D < 6.5) the filament lies down on the cylinder and
tends to align with the cylinder axis. The underlying mechanism of the
bifurcations are discussed and related to buckling and inverted-pendulum-like
instabilities.
