Reference terrain altitude maps are converted by {TAIL ~ a reference map transformation} to data which correlates the reference map to the altitude of {HEAD ~ the missile} 
Reference terrain altitude maps are converted by { TAIL ~ a reference map transformation } to data which correlates the reference map to the altitude of { HEAD ~ the missile }
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD