"Effective human sight and hearing ranges for spotting" Topic

Hi folks, I wonder if anyone could shed light on a range issue.

I'm currently trying to write a set of rules for spotting, in the context of a skirmish in crowded terrain, where the combatants start out not knowing the exact location of their enemies or even unaware of enemy presence on the table.

I'm trying to find out what sort of ranges are realistic for the following (assuming human sense unaided by technology):

- range at which I could hear someone moving around even if they were prone/creeping carefully
– range at which I could see someone clearly enough to visually identify them

and more particularly:

- range at which, if something moved or made a noise, I would reasonably stop following my current orders (e.g. guarding a hut) and go investigate it

My researches are drawing a blank. There are lots of people on the internet keen to tell me that the human eye can see stars that are lightyears away, but that's not the kind of sight I'm looking to represent.

I was thinking of each model being surrounded by a kind of sphere of awareness, which if enemy enter, the model becomes alert and starts attacking the now 'spotted' enemy. The idea being that each figure makes decisions according to its own awareness, rather than my 'god-like' awareness.

Alternatively if people have bad experiences of spotting mechanics and think they just slow down the game, tell me all about it.

Cheers!

What scale game? I would think for 28mm you should be able to spot anything on the table as long as you have LOS and in full light.

In darkness you will need to take light sources into consideration.

It is not a function of range: Spotting is always iffy. You could be right next to someone in the jungle and not be aware. You could be watching a basketball game and never notice something waltzing through.

Watch the vid below and tell me that observation is easy!
YouTube link

For real life, sound can easily carry for a couple hundred feet, especially if walking through underbrush/leaves (and throw in echoes if the person/thing is not in sight.) Similarly, seeing someone is easier if they are moving (even if in place.)

For my own skirmish game rules (always in development ;-), I use a "Threat Awareness" value (basically a result on a D6) that the figure uses to "see" that many non-hiding/hidden opposing figures (starting with the closest.) This "forces" the figure to react to what it would perceive the closest threats to be, much like what would happen in RL… ;-)

Don't forget also the Vietnamese could smell most American troops at a long range due to the food they ate, that is why the LRRPS changed diet before ops to bland Asian food.

And it's hard to hear someone creeping if you're being hit by mortars at the time. I'd suggest modifiers are
Proximity
Blocking/obscuring terrain
Light
Ambient noise
Whether the person is moving, and how fast.

But the modifiers should terminate in a single die roll with no more than four possible results:
1. Nothing out there, Sarge
2. Thought I saw something.
3. I know I heard something, but where is it?
4. There! Right by the rock!

2 and 3 give a bonus on the next spotting roll, and raise the possibility of someone blazing away regardless. Not likely to hit, but might pin, and might wake up friendlies.

Oh. And if you stop guarding the hut and go off to investigate a strange noise, the Sergeant will have words with you when you come back--in the unlikely event that you do come back.

Spotting may not be so difficult at a given range. Accurately identifying what your'e looking at might be though.

Duck

Use your own experience. What can you see in the street, what can you hear. Experiment with a fellow gamer as to how loud a sound has to be before you can hear it, or how far away. Probably as helpful as anything you would get from the nets.

Your physical condition is also a factor, try to be observant when you're dead tired or really hungry. I'm not surprised that you haven't found much.

Try something like an opposed die roll or roll vs a target number. Something like this:
Observer modifiers (+ to die roll):
vigilant = 4, alert = 3, aware = 2, distracted = 1
Target modifiers (+ to die roll):
stealthy = 4, sneaky = 3, normal = 2, clumsy = 1
Observer rolls higher, he spots target, target rolls higher, he is unnoticed.

For our platoon+ sized games I have a catch all that an unknown suppressed section always spots an enemy section at the end of a bound it is within quality range in inches. Which is 4-12.
That's because it's a pain resolving details. Eg exactly where all a section are in buildings which don't match groundscale.
That's not realistic though. As a teenager we played hiding games. If you're static in cover then someone can be 2 feet away and walk past without noticing you.

There's another factor if you're doing rear echelon second rate guards Vs ninja commandos. I've read several accounts where a raider describes a guard seemingly noticing them but they then just walk off. I think some of those times, the guard really did see the raider but decided discretion was safer than raising any alarm.

From personal experience:

If you are wearing any non-naturally occuring color, you will be visible from a long way off, even if you are trying to hide. I could spot people in blue jeans in woods from much further away than people wearing camoflage. Camoflage works.

The further away a gunshot is, the less distinct the source location becomes. If you have become separated and shoot off 3 rounds to attract friendlies, the further away they are, the less likely they will guess your heading correctly. They may even be convinced you are on the exact opposite heading. Sound propagates funny off of trees and hills.

If you are moving, you are going to be seen more likely than not. Especially if you are wearing heavy camo like a ghilli suit. Nothing so attracts the eye as a dashing bush.

When in doubt, 1 minute of automatic weapons fire will confirm or deny any suspicion that the bush ahead contains hostiles or not.

In More Wargaming Pioneers, ed. John Curry, available fyom Amazon, there is a chapter on Michael Korns The Modern Wargame in Miniature (1966) and the skirmish game derived fyom it. Small Unit Tactical Combat(SUTC). SUTC is a 1 to 1 World War 2 double blind umpired game. Regarding the "spotting"issue in doubt, you may wish to see the Observation chart in SUTC. handling the various elements of sight and hearing.
Lets just say that this pioneers work has been built on, its essentials never bettered

Medici,
Here is a real-life source: PDF link

The paper covers the amount of time to detect a target and the different variables that will affect it. Moving targets are much easier to detect. Given enough time almost anything can be spotted.

Long Range Target Recognition: PDF link

"Battlegroup Modern Wargaming Rules" by Ian Clark probably has the best breakdown for spotting ranges in different environments. Also take a look at Panzer War too.

Good luck,
Wolfhag

Lots of military men over the ages have asked that question. Generally, the direction or distance of sounds were difficult to judge, so identifying the sound itself [tanks or the jingling of horse harnesses] were the focus. However, LOS and distances have always been given attention. Here are some from the 19th century:

Antoine Fortuné de Brack, Avant-postes de Cavalerie Légère. Souvenirs. Paris, 1831, p. 105.

At 1.200 m the cavalry can be distinguished from the infantry; the individuals are singled out in the row at 900 m; at 600 m the head is a ball; at 450 m the face, the trunk, the arms in motion, the uniform are differentiated; at 200 m the details are sufficiently clear for the officers to be individualized.

Quoted in Dauriac, The Arms of Napoleon, 2011, p. 129.

Francois Charles Nicolas Jacquinot de Presle, Art and History Courses military. Saumur, 1829, second part, p.404:

At 2,000 meters, men and horses are seen as
points, we do not see their movements.
At 1,200 meters, the cavalry of the infantry began to be distinguished, and that one runs by the flank, one can recognize its files, but one does not distinguishes between movements.
At 800 meters, the movements are marked.
At 700 meters, one can distinguish the head from the rest of the body from time to time.
At 400 meters, one distinguishes it very well.

Brack F., Light Cavalry Outposts. Memories. Paris, 1831, p.161:

At two thousand yards you can see men and horses as points.
At twelve hundred, the infantry and the cavalry are distinguished.
At eight hundred, the individual movements are marked.
At seven hundred, one can distinguish from time to time the head of the rest of the body.
At four hundred, one distinguishes it very well.

Francois Charles Nicolas Jacquinot de Presle, Cours d'art et d'histoire
militaires. Saumur, 1829, seconde partie, p.404:

A 2,000 mètres, on n'aperçoit les hommes et les chevaux isolés que comme des
points, on ne voit pas leur mouvements.
A 1,200 mètres, on commence à distinguer la cavalerie de l'infanterie, et, se
celle-si marche par le flanc, on peut reconnaître ses files, mais on ne
distingue pas les mouvements.
A 800 mètres, les mouvements sont marqués.
A 700 mètres, on peut de temps en temps distinguer la tête du reste du corps.
A 400 mètres, on la distingue fort bien.

Brack F. de, Avant-postes de Cavalerie Légère. Souvenirs. Paris, 1831, p.161:

A deux mille mètres on aperçoit les hommes at les chevaux comme des points.
A douze cents, on distingue l'infanterie et de la cavalerie.
A huit cents, les mouvements individuels sont marqués.
A sept cents, on peut distinguer de temps en temps la tête du reste du corps.
A quatre cents, on la distingue fort bien.

1809 Russian Brief Instruction on the Soldier's Musket the following distances are shown:

At a range of 2,000 paces masses of troops can be seen, at 1,500 cavalry and infantry can be told apart, at 1,000 – the head can be distinguished as a part of the body, at 600 the man can be clearly seen, at 300 to 400 the face and collar, and at 70 to 100 the eyes appear as dots.

The information is the same as in the French Instruction sur le service de l'artillerie, Paris, 2-me édition, 1809.

In 'Firepower' pg 26, Hughes quoting an artillerist manual of 1839-59: (paraphrasing a bit)

" Good eyesight recognizes;
"Beyond 1700 yds. a glitter of arms,
at 1,700 masses of troops,
At 1,300 yds. infantry may be distinguished from cavalry…,A single individual may distinguished from a mass of troops at 1000 yds…,
At 700 yds. the head appears as a round ball and white crossbelts and white trousers can be seen,
At 500 yds. the face may be observed as light coloured spot; the head, body arms and their movements as well as the uniform and firelock (when bright barrels) may be made out.
At between 200 and 250 yds. all parts of the body are clearly visible, and details of the uniform are tolerably clear and the officers may be distinguished from the men."

United States Army. Field Service Pocket Book (1917); page 98-99 Objects are distinguishable to average eyes at the following distances:

9 to 12 miles, church spires
5 to 7 miles, windmills
2 to 2-1/2 miles, chimneys
2,000 yards, trunks of large trees
600 yards, individuals of a column
500 yards, individual panes of glass in windows
400 yards, arms and legs of dismounted men

Objects seem farther away than they really are:

When up a steep hill from the observer.
In poor light such as fog.
When seen across undulating ground.

And there are many others dating from WWII to the present. Note the similarities between the above and the 1970s manuals
in the links provided above by Wolfhag.

Mr. Medici2,

I see Modern War in Miniature and SUTC mentioned above. In Korns' Modern War in Miniature you should look at pages 38 and 39, where Korns describes "Statistical Analysis of Observing". In a footnote he gives as his source "Estimated entirely from field tests." He first gives a formula for "daylight on an average day" followed by "a cloudless night with a new moon". He follows that with variables day and night, and "Variable Continuity".

In his SUTC rules these formulas have been converted into dice tables for use in the game.

By the way, there are two expert practitioners of SUTC (or modified SUTC) still active of whom I am aware: Richard Burnett in California and Rick Nance in the Midwest.

When we wrote the GLORY skirmish rules back in 1984, this was an issue as well. Though the rules was for actions from 1750 until 1914, we did use modern parameters.
After playtesting, the main revision was that the process for spotting, knowing a target is in the area, was different than sighting which shoots at a target.

Spotting for a playable game involves once a target is spotted, it remains spotted for the entire game even if it runs into cover. Spotting includes more than speech which more for command and control, but sounds like falling rocks, crunching leaves or jangling of equipment.
Sight for detection may include seeing a target, seeing shadows, glints of light, reflections and other disturbances.
Another factor is the activity of the spotter. A spotter that is stationary and in an ambush posture will spot more easily than a soldier that is also in the process of moving or in modern cases near noise producing equipment.