The cycle is then repeated a sufficient number of times to transfer a sufficient amount of {HEAD ~ gas} from {TAIL ~ the gas supply line} to the on board storage, at the necessary pressures 
from
The cycle is then repeated a sufficient number of times to transfer a sufficient amount of { HEAD ~ gas } from { TAIL ~ the gas supply line } to the on board storage , at the necessary pressures
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 TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH