Natural Line of Drift

I must thank my SOG Recon Company commander, Capt. Willie Merkerson, for teaching me about natural line of drift over a beer one night in the NCO club. (It was the closest thing to a classroom we had.)

My first step during mission planning was to take a grease pencil and "guesstimate" trail locations on my map, then decide which ones to avoid, which to approach only cautiously, and which to consider for ambushes. Applying what Captain Merkerson taught me, I was able to anticipate nine out of 10 hidden NVA trails in Laos and Cambodia despite the enemy's elaborate camouflage and clever diversions.

Having scribbled Merkerson's advice that night on a bar napkin, I've modified it but slighdy over the years, and I'm now faithfully relaying it to you. Throughout history, man has preferred to travel across ground in habitual ways that save time and conserve effort by seeking the path of least resistance, which eventually became trails, paths, or roads. Man doesn't consciously plan this; he just sort of drifts into traveling certain ways across terrain. We've depicted these habits in the upper left of the illustration on page 321 to show that a human travels:

• Parallel to streams and rivers

• Along the long axis of ridgelines

• At the bottom of valleys

• Along the most direct, easiest route between two inhabited places

■ By using the shortest, easiest route between known trails and roads and other natural lines of drift

Africa Natural Line Drift

As shown in the illustration's lower right, wartime tactical necessity generates additional natural drift habits so that foot soldiers:

• March through woods close enough to see the edge but far enough back to remain unseen

• Cross open areas at the narrowest, lowest point

• Cross streams and trails at bends

• Walk along a ridge's military crest, just below the top

• Occupy the highest points for observation but dig in at the military crest

4 Bivouac near drinkable water

Applying this understanding of human nature allows you to see patterns the enemy doesn't notice himself and enables you to focus your surveillance at places the enemy most naturally will appear.

Hasty, Deliberate, and Detailed Scanning

I've identified three levels of visual scanning to be used when searching for targets: hasty, deliberate, and detailed, executed in that order so you always begin with the fastest and easiest technique.

But whichever you're conducting, I'd advise not to get too logical or too concrete too early. Allow yourself the latitude to "feel" something before looking closely at it, a kind of "What's wrong with this picture?" attitude.

Also, when using optical devices, "layer" your capabilities by one team member using, say, binoculars while the other employs naked eyes or his rifle scope.

And finally, readjust your binocular focus while scanning so it's crisp at exactly the range of each lateral sweep.

Hasty Scanning

Begin with this hasty scan, a quick naked-eye check from close to far, making visual sweeps from left to right and right to left. Start at the nearest terrain feature that could conceal a hostile and move all the way out to the maximum range of your rifle. You're also looking for close threats to your hide.

We've illustrated the hasty scan in the first of two scanning panels on the next page. Notice that you're looking at spots where an enemy most likely would be. Especially taking into account that he's a right-handed shooter, look for him at the low-left corner of each place having ground-level cover. Also apply what you know of natural line of drift, enemy tactics, and human logic. Where would you be if you were the enemy on this ground?

Perhaps you'd spend a minute or two doing a fast hasty scan.

Deliberate Scanning

The same panel illustrates deliberate scanning because you follow exactly the same procedures, only this time with binoculars.

One significant difference is that your visual sweeps are jerky and jump from likely-locale to likely locale, but since you're now

Hasty and deliberate scanning both look in the same places, but use binoculars for deliberate scans.

using optics, you pause long enough at each for your mind to register impressions. You're looking for grapefruit-size pieces of a concealed enemy.

Roughly, I'd recommend spending three to five minutes doing a deliberate scan.

Was this article helpful?

+2 -2
Hunting Mastery Selected Tips

Hunting Mastery Selected Tips

Deer hunting is an interesting thing that reminds you of those golden old ages of 19th centuries, where a handsome hunk well equipped with all hunting material rides on horse searching for his target animal either for the purpose of displaying his masculine powers or for enticing and wooing his lady love.

Get My Free Ebook


    What is a natural line of drift?
    4 years ago
  • james meade
    How to determine natural lines of drift?
    2 years ago

Post a comment