A series of unsteady CFD simulations have been conducted for a set of generic isolatedand installed-propeller configurations at low-speed flight conditions. The propeller geometry investigated is a four-bladed design typical of those used on modern regional turboprop aircraft. The computations were performed with the unstructured DLR TAU-code and the numerical results are compared with experimental data obtained in a wind tunnel test campaign conducted in the 1980s. The results of the unsteady computations agree well with the available propeller slipstream data and surface pressure distributions measured in the wind tunnel. Additionally, a detailed analysis and comparison of the forces acting on the wing and the propeller is performed.