The present contribution is devoted to the aero-thermal experimental study of a trapezoidal cross-section model, reproducing a trailing edge cooling cavity with one rib-roughened wall and slots along two opposite walls. Four rib geometries are compared to investigate the effect of the relative position of ribs and slots, as well as the tapering of the turbulators. The Reynolds number, defined at the inlet of the test section, is set at 67500 for all the experiments. Insight into the flow field for the different geometries is gained by means of surface streamline flow visualization. Highly resolved heat transfer distributions over the channel walls, including the rib surface, are obtained using steady state liquid crystal thermography. The results demonstrate how the overall thermal performance of the cooling scheme can be enhanced adjusting the rib position with respect to the slots. Moreover, the beneficial effect of tapering the ribs is shown.