In this paper, we have studied experimentally and theoretically the flutter instability
of cantilevered flexible plates in uniform flow. We have shown in particular that the
three-dimensionality of the flow has to be taken into account to predict accurately the
instability threshold as the plate aspect ratio is varied. We have also shown that hysteresis
is present for plates of large aspect ratio and that the instability threshold measured when
increasing the velocity does not converge towards the two-dimensional limit as aspect
ratio tends to infinity. These experimental results are now discussed with regard to the
assumptions made in the stability analysis.