A deviation from the intermediate point to a new intermediate point is determined such that the new intermediate point has {HEAD ~ a cumulative threat risk value} lower than or equal to {TAIL ~ the allowable threat risk} per grid cell 
A deviation from the intermediate point to a new intermediate point is determined such that the new intermediate point has { HEAD ~ a cumulative threat risk value } lower than or equal to { TAIL ~ the allowable threat risk } per grid cell
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 HEAD HEAD HEAD HEAD REL REL OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH