A bearing assembly for a wind turbine includes a bearing housing and a bearing surface defining a passageway configured to receive a shaft. The bearing surface includes a stationary portion and a movable portion, the movable portion being defined by a movable member coupled to the bearing housing. The movable member is movable between a first position, wherein the movable portion is flush with the stationary portion such that the bearing surface is smooth, and a second position wherein the movable portion is spaced from the stationary portion to define a fluid cavity in the bearing surface. A method of operating a plain bearing assembly includes operating the plain bearing assembly as a hydrostatic plain bearing during low dynamic conditions and operating the plain bearing assembly as a hydrodynamic plain bearing during high dynamic conditions.