The Wageningen Propeller B-Series are used by designers and engineers worldwide. These series comprise the open water characteristics of conventional fixed pitch propellers with various numbers of blades and blade area ratios for different pitch. For several of these propellers, also the characteristics in 4-quadrants (positive and negative rpm and positive and negative speed) were published by MARIN in the sixties and seventies. Today many ships are equipped with Controllable Pitch Propellers (CPP). Both for ships and offshore structures, use is made of ducted CPPs. The thrust-torque performance of these units is not only of importance for ship designers but also for accurate analysis of speed trial results, DPsystems and DP-simulation models and manoeuvring simulators. Due to lack of this systematic information for CPPs in such cases, normally use is made of the B-series data. The characteristics of CPPs, however, differ substantially from those of fixed pitch propellers. For these reasons a Joint Industry Project called“ Wageningen Propeller C- and D-Series” is initiated. In addition to the propeller thrust and torque, the hydrodynamic characteristics of the blade spindle torque will also be measured.