In another embodiment, {TAIL ~ reference data} could be provided by {HEAD ~ other aircraft systems} 146 
In another embodiment , { TAIL ~ reference data } could be provided by { HEAD ~ other aircraft systems } 146
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH