Approximate methods for calculating the surface pressures including the effects of viscous interactionare introduced for laminar and turbulent boundary layers. Experiments were performed with various models taking Schlieren pictures and pressure measurements. The flow over a two-dimensional compression corner showed transitional separation and were in agreement with other authors. The investigation of the flow over a delta wing with trailing edge flaps and body showed an influence of transition on the shape of the separated area, the pressure measurements were compared with various two-dimensional approximations. The experiments of a flow in the junction between a circular cylinder and a flat plate showed the influence of the sweep angle on the size of the separated region.The University