Noise reduction in counter rotating fan propulsion is accomplished by providing an engine core, driving {HEAD ~ an outer blade row} from {TAIL ~ the engine core} and driving an inner blade row from the engine core 
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Noise reduction in counter rotating fan propulsion is accomplished by providing an engine core , driving { HEAD ~ an outer blade row } from { TAIL ~ the engine core } and driving an inner blade row from the engine core
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH