A rotor blade system includes a rotor, a casing radially spaced apart from the rotor, and a plurality of blades coupled to the rotor and positioned between the rotor and the casing. The one or more of the plurality of blades have a radial length different from a remaining one or more of the plurality of blades so as to vary a tip gap between a tip of the one or more of the plurality of blades and the casing to break up a frequency content of a leakage vortex at the tip to modify natural frequencies of the plurality of blades and mode shapes to reduce or substantially eliminate flutter.