Hydrodynamic plane thrust bearing (26) for a generator (10), preferably operable with a water turbine, with a rotor (12), a track ring (30) rotating with the shaft (20) of the rotor (12), and a bearing segment (32) not rotating with the shaft (20) of the rotor (12) and supported on a bearing housing (24), characterized in that the track ring (30) substantially consists of a plastic matrix with reinforcing fibers embedded therein.