a tip turbine engine and a method of operating the engine provides increased efficiency while eliminating or educing the number of axial compressor stages by moving the core airflow inlet aft of the fan . as a result , the core airflow entering the core airflow inlet is the fan exhaust , which is already at an increased pressure . a portion of the fan exhaust is guided radially inward , then axially forward and then radially outward through compressor chambers in the hollow fan blades for further , centrifugal compression .