For this purpose, {HEAD ~ the bases} of the outer trailing edges of {TAIL ~ the second row blades} have a negative propulsion angle 
For this purpose , { HEAD ~ the bases } of the outer trailing edges of { TAIL ~ the second row blades } have a negative propulsion angle
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH