{HEAD ~ A trailing surface} aft of the maximum radius has a radius at {TAIL ~ all points} therealong less than the maximum radius 
{ HEAD ~ A trailing surface } aft of the maximum radius has a radius at { TAIL ~ all points } therealong less than the maximum radius
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH