Each of the cooling shoes includes an air expansion chamber communicating through a shoe inlet when in use with a supply of {HEAD ~ air} under {TAIL ~ pressure} 
under
Each of the cooling shoes includes an air expansion chamber communicating through a shoe inlet when in use with a supply of { HEAD ~ air } under { TAIL ~ pressure }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL