Computer 26 may also receive signals from {TAIL ~ one or more fluid temperature sensors} 40 and {HEAD ~ one or more fluid compressibility sensors} 42 
Computer 26 may also receive signals from { TAIL ~ one or more fluid temperature sensors } 40 and { HEAD ~ one or more fluid compressibility sensors } 42
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH