Structure borne sound sensors or ion current sensors may also be used to detect a variable characterizing {TAIL ~ the combustion} in {HEAD ~ a combustion chamber} 
Structure borne sound sensors or ion current sensors may also be used to detect a variable characterizing { TAIL ~ the combustion } in { HEAD ~ a combustion chamber }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD