The reference map transformation values are used in {TAIL ~ conjunction} with {HEAD ~ a terrain correlation process} to establish vehicle position 
The reference map transformation values are used in { TAIL ~ conjunction } with { HEAD ~ a terrain correlation process } to establish vehicle position
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH