When {HEAD ~ fuel flow} is directed to {TAIL ~ the last zone} by the fuel control the fuel flows directly to the upstream sprayring, while fuel flow to the downstream sprayring is controlled by a valve which is closed at a lower range of bypass ratios and open at a higher range of bypass ratios to direct fuel thereto, for spraying adjacent the outer wall 
is directed to
When { HEAD ~ fuel flow } is directed to { TAIL ~ the last zone } by the fuel control the fuel flows directly to the upstream sprayring , while fuel flow to the downstream sprayring is controlled by a valve which is closed at a lower range of bypass ratios and open at a higher range of bypass ratios to direct fuel thereto , for spraying adjacent the outer wall
OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH