Ahead of the installation of a commercial tidal stream turbine, a 1:30 scale model of the device was tested in a recirculating flume tank. This proved to be the first physical demonstration of the turbine’s unconventional control strategy, which limits the thrust forces on the device by allowing the rotor to enter an overspeed. The tests showed that this simple to implement concept of operation is a cost-effective and reliable means of managing the rotor thrust loads in energetic flows. Subsequent tests highlighted the importance of correctly calculating the controller gain parameter, otherwise detrimental turbine performance characteristics can be expected. When relating these results to that of the commercial device, there are a number of important differences associated with both the environment and scale of the model tests. Despite this, the results are considered encouraging, and provided confidence for the full-scale deployment.