If you've spent any time in the military at all, you know there are a number of ways to cross a linear danger area, the term we used to describe an area of vulnerability for patrolling soldiers, SWAT guys or whatever. This can be something as obvious as a road or firebreak indicated on maps or a terrain feature you tab onto as you're moving, like a streambed.
Most militaries have a number of different ways of crossing a linear danger area (LDA) and they're remarkably similar. I heard of a new one recently, however, in a remote little bar in Indian Springs, NV (the Oasis maybe?) while tipping back a few with a couple of salty émigrés from the former Rhodesia after a combat tracker class over in the Creech/Silver Flag area. Rhodesians, by and large, operated in four-man 'sticks' or 'call-signs' largely because of the troop-carrying capacity of their helos. Even in Fireforce operations (a heliborne call-sign functioning in many ways like our current QRFs overseas) they rarely operated in large numbers. The necessity of operating in small teams and widespread employment of trackers fundamentally affected the development of their small unit infantry tactics, only some of which resemble the standardized infantry movement TTPs of our boys.
Any tracking team conducting a follow-up in a rural area is going to find itself needing to cross an LDA. This technique for doing so is based upon the Rhodesian method (and, not coincidentally, is the tactic taught by the Tactical Tracking Operations School). It is diagrammed here utilizing a five-man tracking team, but can just as easily be accomplished with a four- or six-man team.
Instead of moving up on an LDA, establishing near-side security, rally points and fireteam movements, this movement should be a natural extension of the team's movement, calling for a minimum of direction from the controller (Team Leader). It is fairly simple and has been proven effective. Note that one of the foundations of such a tactic is that the tracking team is well trained, rehearsed and its members used to operating with each others or with other trackers of identical methodology.
(Note: the diagram intervals between team members, spacing and size of the operational area are not to scale.) The red arrow indicates the direction the track line is taking them. The team's two flankers (LF and RF) out to the sides of the Y formation as they should be, tracker (T) on the track line and controller (C) back from the tracker, with a rear security tracker (RST) at the rear, alternately glassing ahead with a weapon optic or binoculars and then checking security to the rear of the team.
One of the flankers has observed the nearing LDA and communicated this on to the controller via hand-and-arm signal. Tracking team comes on line in the same deployment as they would with a contact front. Flankers keep out in their area of responsibility. Tracker moves straight up to the LDA, maintaining the location of the last known spoor to prevent contamination. Tracker attempts to identify spoor on the LDA and determine if the team can safely move across without contaminating. Flankers will similarly be examining the ground to their front to ensure the quarry has not done a hard direction changed and moved off either direction down the LDA as part of anti-tracking attempts. RST will cover forward or continue to watch the rear of the team as determined by the tactical situation and the environment.