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In this thesis, the feasibility of using blade-mounted servoflap actuation or conven-tional root pitch (swashplate) actuation to control helicopter vibration is investigated. A linear, time invariant, state space model is derived and presented in a form of fre-quency response (Bode plot) which is useful for control studies. Multi-blade coordi-nates are used to transform the blade's degrees of freedom in the rotating frame to the rotor disk modes in the non-rotating frame in order to achieve linear, time invariant system. The linearized model provides general trends of the rotor blade behavior at different flight situations but may not be as accurate at high advance ratio cases. The model was used to investigate the feasibility of using the servoflap actuation on a one-sixth scale CH-47 model rotor. It is found from the model that as little as 3 deg of servoflap deflection can achieve significant level of vibration reduction. Surprisingly, it is also found that an inboard actuator (f = 0.6-0.8) is more effective than an outboard actuator (f = 0.8-1.0). The root pitch actuation is found to be less effective than the servoflap actuation, due to a zero introduced in the transfe