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Boundary layer ingestion constitutes an integrated propulsion concept in which the propulsoris located at the aft section of the fuselage and hence operates under the in uence ofthe boundary layer  ow instead of the freestream. Under this condition, the necessarypower to produce a given thrust is lower than for a propulsor operating in the freestream.As a result, the aircraft's fuel consumption is reduced. The investigation undertaken inthis thesis aims to improve the understanding of potential power-saving in the frameworkof a propeller-driven 19-passenger commuter aircraft. The intention was to build a fasttool to analyze propeller performance for uniform and nonuniform in ow conditions. Inthis regard, the code should allow a  exible change of the input parameters such as  ightconditions, thrust requirements, and fuselage geometry. For this purpose, the propellerdesign and analysis tool XROTOR is utilized in combination with the airfoil analysis toolXFOIL to simulate the nonuniform in ow condition of a BLI propeller.The results are divided into two parts. First, a comparison of an isolated propeller withuniform and nonuniform in ow is conducted. For this, the boundary layer data of asimpli ed fuselage geometry generated with XFOIL is used to derive a velocity pro leat the propeller inlet plane. Then, the comparison is displayed in a standard propellerperformance map. Here the BLI propeller shows increased thrust to power ratios and theability to operate in a broader range of advance ratios for each pitch angle. In a new,generalized map more suitable for showcasing power-savings, the comparison indicatesbene ts of up 24%. Furthermore, an investigation of the aerodynamic occurrences alongthe propeller blades shows increased local eciencies, most notably in the hub region, aswell as reduced axial momentum. However, an increased residual swirl can be observed,adding further kinetic energy losses.In a second step, di erent geometries and thrust settings of the BLI propeller and itsin uence on a system-wide power-saving are analyzed in a design space exploration. Itis assumed, the conceptual aircraft operates in a hybrid-electric con guration, wheretwo wing-mounted propeller engines supply the electrical energy for the BLI propeller.Consequently, the total thrust requirement of the aircraft is distributed between the threepropulsors. Under this condition, certain transfer losses due to electrical machinery haveto be incorporated. Assumed losses of 10% and 3% re ect the technological possibilitiesof the timeframes up to 2035 and 2050, respectively. An initial, system-wide powersavingof up to 5% is diminished to 1.5% and 3.5%, incorporating these transfer losses.Large radii are most bene cial in terms of power-saving. However, a possible weightpenalty and constraints due to the geometrical limitations of the aircraft reduce the designspace signi cantly. Finally, a summary and conclusions of the research  ndings andrecommendations for future works are given.