Large Eddy Simulation is employed for the investigation of the wake instability ofa submarine propeller in open water conditions. The time-resolved velocity and pressure fields are computed in the near wake where the instability occurs. The study focuses in particular on the analysis of complete time series of the flow velocity at the probes in the wake. The results are compared with Laser Doppler Velocimetry measurements. © 2010 Institute of Ship Technology and Ocean Engineering.