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