Distributed Propulsion (DP) in general and Distributed Electric Propulsion (DEP) in particular is a new technology that promises to significantly increase the overall efficiency of aircraft and thus reduce CO2 and other emissions. Unlike today's commercial aircraft configurations, which are powered by two or four underwing engines, DEP/DP involves distributing a large number of smaller propulsion systems across the span. DEP/DP offers increased design space in terms of reliability, safety, and weight distribution. However, not all the interrelationships in such integration have been investigated or understood. On top of that, a reliable prediction of the aerodynamic effects of DEP/DP with close wing coupling at the edge of the flight envelope based on aerodynamic models and simulations is not yet possible. This is especially true in the high-lift regime, where the wing tends to detach and exhibits strongly nonlinear aerodynamic effects. Unsteady propeller-propeller and propeller-wing interactions are a major challenge here. Therefore, the goal of InPAH is to fill this gap by providing high fidelity experimental data for these aerodynamic effects and characterization for tightly coupled DEP/DP. In addition, a validation of numerical simulation techniques of varying complexity will provide a path to a sound and reliable prediction of the phenomena. Design parameters that determine both positive and negative aerodynamic effects will be identified and quantified. The interaction of the propellers with each other, the effect of the airfoil on the propellers, as well as the effect of the propeller jet on the airfoil are considered.