The last zone comprises a set of {HEAD ~ two axially spaced sprayrings} located adjacent {TAIL ~ the outer wall} of the afterburner, one spraying being located upstream of the other spraying 
The last zone comprises a set of { HEAD ~ two axially spaced sprayrings } located adjacent { TAIL ~ the outer wall } of the afterburner , one spraying being located upstream of the other spraying
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH