List of water speed records
The world unlimited water speed record is the officially recognised fastest speed achieved by a water-borne vehicle, irrespective of propulsion method. The current unlimited record is 511.11 km/h (317.59 mph; 275.98 kn), achieved by Australian Ken Warby in the Spirit of Australia on 8 October 1978.
Source: Wikipedia — List of water speed records (CC BY-SA 4.0)