Further, the method includes enlarging the hole until the sensed parameter represents {HEAD ~ a preselected air flow rate} through {TAIL ~ the hole} 
through
Further , the method includes enlarging the hole until the sensed parameter represents { HEAD ~ a preselected air flow rate } through { TAIL ~ the hole }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL