Modern passenger airliners are designed with optimal efficiency in mind. Therefore, air- craft are equipped with engines of ever increasing bypass ratio. However, the increased engine cross-section and the proximity between engine nacelle and wing cause several in- teraction phenomena that negatively impact aerodynamic efficiency. This is significant as airframe and engine are usually developed separately, without these interactions in mind. We endeavour to identify these interaction phenomena through integrated simulations of airframe and running engine. The engine is modelled as a bypass channel with rotating fan based on NASA Rotor 67. The airframe is based on the NASA Common Research Model (CRM). Airframe and rotor are discretized as two separate domains with unstruc- tured tetrahedral meshes. Transition between the domains is realized through sliding mesh interfaces with the rotating domain treated as a frozen rotor. Boundary conditions were selected to provide rotor inflow conditions similar to NASA Rotor 67 to verify the rotor flow. Surface mesh quality improvments enable a more stable computation with improved convergence behaviour. Our results show how engine intake spill flow alters the pressure distribution at the wings, negatively impacting lift. The altered pressure distribution in turn affects the exhaust jet, which then impacts thrust.