Installation effects on the S-duct intakes of a high power turboprop were investigated by comparing three different nacelle configurations as the channel wing, over-the-wing and conventional tractor wing using computational fluid dynamic methods. The interaction of the propeller, the wing, and the nacelle on the scoop type turboprop intakes were identified in terms of recovery and distortion on the aerodynamic interface planes. An actuator disc model was used to simulate the propeller downstream effects. The channel wing installation of S-ducts showed approximately 2% higher total pressure recovery than the other configurations. The channel wing configuration with a wrap-around S-duct experienced a 2% lower circumferential distortion intensity, whereas over-the-wing had an increase by 3% in comparison to the tractor wing. It was also observed that the S-duct type had a greater influence on the radial distortion intensity than the installation type. The swirl coefficient distribution showed that multiple peaks occurred as opposed to swirl results based on a single sector of the aerodynamic interface plane. The difference between swirl peaks of shaft penetration S-duct was reduced by 14% when installed on channel wing, whereas the peaks of wrap-around experienced 90° phase shift, and their difference showed 10% increase on channel wing.