A method for linearizing the first-order dynamics of a fixed-pitch, vertical axis hydrokinetic turbine about an operating point is detailed. The system’s frequency response to turbulence and controller action is determined. Turbine parameters contributing to its dynamics are described and the effects on system response of geometrically scaling a turbine are explored. The turbine’s sensitivity to turbulence across a wide frequency band is compared to the turbulent kinetic energy (TKE) present in a tidal channel across the same frequency band. The turbine is found to be most sensitive to low-frequency turbulence and control action perturbations, with decreasing gain at higher frequencies. Larger sized turbines are shown to have a lower magnitude response over a narrower frequency band. The turbine is shown to be more responsive to the most energetic turbulence frequencies. This method of analysis and subsequent results can inform controller design aspects such as the determination of control action frequency and magnitude.