Minefields should injure rather than kill

[JonS]

I'll argue.

I wouldn't have it any other way.

conflating a possible casualty radius with an ensured casualty radius.

I don't think so. Lethal radius is given as 22x, casualty radius is given as 110x. Sure there are a lot of variables (orientation of mine's horizontal axis c.f. the horizon being a prime one), but I don't think I've never seen "lethal radius" downgraded to "possible casualty radius" before.

A single s-mine NEVER killed an entire squad.

That's a bold statement.

s-mines were, essentially, equivalent to a hand grenade.

Sure. If you ignore the order of magnitude differences in important dimensions (weight of explosive filler, casualty radius) and operational differences (airburst vs ground burst) then yeah: they're essentially equivalent.

[c3k]

Let's take this one at a time.

Lethal radius. That does NOT mean that 100% of the people within that distance will die.

Let's say a grenade has a 15m lethal radius. That's an area of about 750m^2. I could easily put 750 men there. One grenade going off in their midst will NOT kill 750 men, despite all of them being inside the "lethal" radius. That proves that lethal radius does NOT mean death. It is a statistical probability of causing lethal casualties. Usually given as 50% chance vs. a standing individual, if my memory serves. (Maybe I'm forgetting the specific %. Shrug.)

Casualty radius is the same: a probabilistic statement. It speaks to the energy of most of the wounding chunks of metal. It's all bell curves.

If I stand 100m from a grenade detonating, I'm probably okay. I sure wouldn't want to do it, but if that's what happens, shrug. Otherwise, one grenade would wound every soldier in a football field. Defense would be easy.

My statement that s-mines were, essentially, equivalent to a hand grenade is true. The s-mine was lighter, but more effective given its weight due to the airburst and guaranteed proximity of victim. A grenade has no such guarantee, but it does have thicker metal chunks (except for so-called "offensive" grenades such as the German stick grenades), and more filler. However, a grenade may land on the other side of a tree, or in a gopher hole. So, yes, "essentially" the same.

(If you've ever heard of an entire squad being killed by an s-mine, I'm eager to hear about it. Absent evidence to the contrary, I'll stand by that. The filler is too light, the casing too thin. One man between you and the s-mine would keep you safe.)

Ken

[JonS]

S-mines had more filler than based. S-mines incl ball bearings (cf claymore) for extra cas.

[Baneman]

I still wish that a lethal blast radius was modelled.

It's frustrating to see a mortar round land between a guy's feet ... and he walks away. Strangely, grenades at those sorts of ranges are deadly much more often.

[c3k]

Some filler:

S-mine (schrappnel (sp?) Mine):

Characteristics[edit]

S-mine in a museum

The German S-mine was a steel cylinder less than 13 centimetres (5.1 in) tall without its sensor and only 10 centimetres (3.9 in) in diameter. A steel rod protruding from the mine's top held the main fuse, where its trigger or sensor was attached. The SMi-35 had a central fuse, while the SMi-44 had an offset fuse. It weighed approximately 4 kilograms (8.8 lb), with the weight depending on whether it was loaded with the lighter powdered or the heavier poured TNT.[1]

The main charge of the mine used TNT as its explosive; the propelling charge was black powder. The standard pressure sensor used a percussion cap to ignite it.[12]

The main fuse was designed to delay the firing of the propelling charge for approximately four seconds after the mine was triggered. The explosion of the propelling charge sent the mine upwards into the air and activated three short-delay pellets between the propellant charge and the three detonators. These short-delay pellets delayed the mine's detonation long enough for it to reach an appropriate height before exploding.

The standard pressure sensor was designed to activate if depressed by a weight of roughly 7 kilograms (15 lb) or greater. This ensured the mine was not detonated by wildlife or natural impact of blowing leaves, branches, or other normally occurring phenomena.[1]

Usage[edit]

Diagram of S-mine detonation

The S-mine was normally triggered by a three-pronged pressure fuse. It could also be modified to be triggered by a tripwire. A special tripwire adapter was provided by the German army. The steel tube that held the fuse was threaded to accept any standard German ignition or trigger, allowing the sensor to be removed and the mine to be deliberately triggered by a human operator.[1] When triggered, the mine functioned in two stages (see diagram).

1. First, the mine was fired .9 to 1.5 meters (2 ft 10 in to 4 ft 10 in) up into the air by a small propellant charge.
   
2. Approximately a half-second later, the main charge detonated at the optimum height to kill or severely injure anyone in the immediate area.
   
3. The main charge of the mine was surrounded by roughly 360 steel balls, short steel rods, or scrap metal pieces. These became metal shrapnel that sprayed horizontally from the mine at high velocity.

The time between triggering and ignition of the propelling charge varied between 3.9 and 4.5 seconds, depending on the age and condition of the mine. According to German documentation, the S-mine was lethal within 20 meters (66 ft) and could inflict casualties within 100 meters (330 ft).[1] American training manuals warned of casualties at up to 140 meters (460 ft).[12]

A common misconception prevailed that the S-mine would not detonate until its victim stepped off the trigger. This fallacy was propagated by incorrect United States propaganda during World War II. The mine would detonate whether the trigger was released or not. Standing still or attempting to run from the S-mine would be equally dangerous. The most effective way to survive the mine's detonation would not be to flee but to fall to the ground lying face down as quickly as possible.

S-mine dischargers, in the form of angled tubes attached via brackets to the hull, were also used for anti-infantry defense by Wehrmacht armored vehicles. Early versions of the Tiger I were equipped with five such devices.

========================================================

US "Pineapple" Grenades:

Mk II and Mk IIA1[edit]

More commonly known as the Pineapple, the Mk II series (also written Mk 2) was the most common US fragmentation grenade of the Second World War. The Mk II had a grooved exterior originally intended to aid fragmentation of the grenade. However, later studies showed that this design has no effect on fragmentation, though it does provide a non-slip surface that improves grip. The filling is either TNT (approx. 2 oz or 57 g), or EC blank fire powder (approx. 0.75 oz or 21 g smokeless small arms powder).[1][2]

The Mk II was also available in a little-known HE-Blast (better known as concussion) variant and a combined effect HE-Frag variant.[2] This was largely superseded by the Mk III series. The Mk IIA1 (also written Mk 2A1) used the M10A2 or M10A3 fuzes, upgrades to the previous M10A1 fuze used in the Mk II.[3] Later reissued Mk II variants featured the modern M204 series fuze.[4]

Mk III, Mk IIIA1, and Mk IIIA2[edit]

Unlike the Mk II, the Mk III (also written Mk 3) was a cylindrical grenade designed to be used as an offensive weapon for clearing rooms, trenches, and other enclosed spaces (i.e., at close range). A concussion grenade, the Mk III series was designed to incapacitate through the pressure and impulse produced by the explosion. The MkIII had a far larger TNT filling than the Mk II series; up to 8 oz (230 g) of TNT, in comparison to 1.8 oz (51 g). Although a minimum-fragmentation grenade, large fragments (most likely the fuze assembly, or surrounding material) could be projected as far as 200 m (660 ft) from the detonation point. The differences between the Mk III, the Mk IIIA1 (also written Mk 3A1) and the Mk IIIA2 (also written Mk 3A2) were improved versions of the M6 fuze: the Mk III featured the M6/A1, the Mk IIIA1 the M6A2, and the Mk IIIA2, the M6A3.[3] Later reissued Mk III variants featured the modern M206 series fuze.[2][4]

======================================================

German "stick" grenade:

ONE: STICK HAND GRENADE, MODEL 24 (STIELHANDGRANATE 24)

A. How to Identify

The stick hand grenade, Model 24, may be identified by:

(1) Metal casing or body screwed onto a wooden handle with a metal cap.

(2) Model marking on the casing or body of the grenade.

(3) Porcelain ball attached to a cord in the exposed cavity after the metal cap is unscrewed.

B. Characteristics

General. This grenade consists of a thin iron or steel casing, or head, containing the explosive filler and screwed onto a hollow wooden handle, through the center of which runs a double length of cord. This cord is attached at one end to a lead ball which is part of the 'friction-igniter-detonator system, and at the other end of a porcelain ball. The cavity in which the porcelain ball rests is closed by a metal cap that screws on. Inside the cap is a spring-actuated metal disk that prevents movement of the porcelain ball.

Figure 25. Sketch of Stielhandgranate 24 (stick hand grenade, model 24) showing outside and cross section of grenade and fuse. (The cross section of the grenade is drawn to a larger scale than the scale of the sketch of the outside view.)

Table of characteristics.

Over-all length 1 foot 2 inches.

Weight 1 pound 5 ounces.

Weight of explosive filler 6 ounces.

Time of delay fuse 4 to 5 seconds.

Effective blast radius 12 to 14 yards.

=================================================

Ken again (the above was all cut and paste).

Explosive filler:

s-mine: 6 oz. (TNT)

US: 1.8 oz. (TNT)

Stick: 6 oz. (TNT)

Casing is the key: a thin casing with large filler produces tiny fragments which slow down rapidly. A thick casing with small filler produces big chunks of fragments which go further. One is offensive (so you don't hurt your own troops) the other is defensive, and assumes you have cover behind which you can shelter. The s-mine is IDENTICAL (essentially ) to the "offensive" stick grenade which has long been noted for its wounding ability, not its lethality.

Sources:

http://en.wikipedia.org/wiki/S-mine

http://efour4ever.com/grenade_german.htm

http://en.wikipedia.org/wiki/United_States_hand_grenades

[cool breeze]

But the S-mine seems to have the explosives of an offensive mine with the thick casing and other big shrapnel of the defensive grenades. The total weight of the S-mine is much higher that the weight of the stick grenade. I assume that weight it mostly casing. It seems to me the S-mine has more casing than the US Mk II and apparently the same amount of TNT as the german stick, and it airbursts. The S-mine weighs 8.8 pounds vs. stick grenades 1.5 almost 6 times more.

[ArgusEye]

The S in S-mine is for 'Schnell' which means 'quick'. This referred to a large area of denial being covered by one mine, using the tripwires, or it being quickly converted to other detonating methods in the field without much additional equipment.

According to a Dutch mine-lifters' manual from 1948, the rumour that the mine could be disarmed after you stepped on it was introduced deliberately by the British. The druckzünder had a three second delay (which would get longer as the mine deteriorated in the ground), so that a soldier would have stepped off the mine when it jumped. If a soldier could be convinced to stay on top of the device, he'd get blown to kingdom come, but the rest of the squad would stay safe.

Since it didn't have to go through the rigours of being fired from a gun, its casing and filler could be designed for optimum fragmentation. Outside of its plane of maximum fragmentation, it was not very strong, but within it there was a lot of large shrapnel flying around. The mine-lifters' manual warns it has to be encapsulated equivalently to a 105mm artillery round.

[poesel]

The S in S-mine is for 'Schnell' which means 'quick'.

The 'S' stands for:

-'Schrapnell' = shrapnel or

- 'Splitter' = fragment, splinter or

- 'Spring' = jump

[c3k]

... and now we should ALSO include the "shoe" mine. Small, wooden box, enough to blow the front of a foot off. How does that affect the rest of the squad? What mix of "s" and "shoe" mines? What of the US/Brit types?

[JonS]

... and; what does it actually matter whether they're recorded as dead or wounded?

[JasonC]

On what the different radii mean, if you see the term of art "effective casualty radius" - which needs the "effective" to have the following specific meaning, then it means

"The EFFECTIVE CASUALTY RADIUS of a hand grenade is defined as the radius of a circular area around the point of detonation within which at least 50 percent of the exposed personnel become casualties. The radius is about 16.5 yards (15 meters)".

Much larger figures frequently cited as casualty radii (no "effective", perhaps predating this cold war NATO standard usage, etc) frequently are instead a safe distance or hazard zone, meaning the max distance at which a standing man *might* be wounded significantly by flying fragments. Without any connotation of actually wounding half of all standing exposed personnel in that distance. Notice the small radius quoted above for a typical fragmentation grenade, for example. The same "effective casualty radius" for e.g. a 40mm grenade launched by an M79 or M203 etc is 5 meters.

A sample item given a 60 meter effective casualty radius in NATO terms is a 500 pound general purpose bomb. A bouncing betty mine is not a 500 pound bomb.

Note that the effectiveness of fragmentation falls off somewhat faster than the square of the radius. Fragment coverage drops that fast, but each fragment is also losing energy with distance, making some portion of the smaller fragments ineffective as the distance increases, in each farther "shells" around the detonation.

There is no way in heck a single small mine would wound half of exposed personnel in a 110 meter radius. That is much more like the farthest distance at which any of its fragments would penetrate deep enough to cause a significant wound, if one happened to hit anyone.

[JasonC]

So I got interested enough in this question that I decided to simulate it.

I wrote a Mathematica program that generates a random height above ground level for the mine to go off, from a normal distribution with average 1.2 meters and standard deviation 0.15 meters. That puts 2 SDs on either side of the mean in the 0.9 to 1.5 meter range quoted in the source above.

Next I generate a random direction for each of 360 projectiles, with the compass angle a uniform distribution around the circle, but the angle from the horizontal a tighter band. The band is given a mean of 0 degrees and a standard deviation of 15 degrees, so that 2 SDs on either side of the mean give plus or minus 30 degree angles from the horizontal.

I don't simulate gravity or the fall of the projectiles, which means my estimates at long range are going to show more lethality remaining than you would actually see. But basically the issue is, some of the angular regions outward from the explosion point just randomly won't have many projectiles in them, and others will have only projectiles angled up or down that will impact the ground (downward ones) or pass above a man's height (taken as 1.8 meters) and so fail to be dangerous to a standing man, outside of a certain range window around the blast point. The farther from horizontal the up or down angle for each of the 360 projectiles, the shorter this range window becomes.

The projectile paths are light rays from that initial direction, around the circle and upward or downward tilted.

Then for each 5 meter distance increment, I generate 1000 random hypothetical person positions, randomly placed around the circle. For each person I ask for the nearest passing projectile at that range. If its distance from the random person is less than 1/4 of one meter, I count it as a hit. This effectively makes each random person position a half meter wide window for each projectile. (Obviously a man might be wider in one orientation than in another, and at one height than another - I ignore those complications for simplicity as a first pass. But see below for more on the influence of the cross-section used).

The simulation shows a near-certainly of a hit at 5 meters - 994 out of 1000 on my test run. This drops to 68.4% at 10 meters, 30% at 20 meters, and is still about 10% at 45-50 meters. The good "carry" reflects the horizontal direction of many of the projectiles and my idealizations ignoring gravity etc.

The 50% chance range works out to 13.4 meters, using an interpolation function between the hard-simulated 5 meter distances. That is quite similar to the NATO hand grenade figure, incidentally, which may of course be generous for all we know, compared to this simulation. At the 22 meter distance, the hit chance comes out around 25%. At 100 meters it is down to 2%.

The simulation can be used to test how important exposure cross section is. If the nearest projectile has to pass within 4 inches of the person's center (8 inch effective width of exposure), for example - just sideways to the blast could give that or better - then the 50% distance drops to 8.5 meters, the risk at 20 meters drops from the 30% figure above to 20%, and the 10% risk distance drops to 34 meters from the 45-50 above. Being prone would help rather more than that, because it would also require a narrow band of vertical angles to intersection the man's position at any given range, away from the horizontal "peak" of the vertical-angle distribution.

FWIW.

[Michael Emrys]

I love it!

Michael

[Baneman]

So very roughly that's saying that 50% of all upright troops in an Action Spot when an S-mine goes off should at least be wounded. :eek:

That's probably too lethal for gameplay, but as it stands in game, mines only appear to affect the guy who actually stands on it.

Btw, anyone know what sort of mines the Allies used ? Was there any equivalent to the "jumping" S-mine or was that a uniquely German weapon ?

[Bulletpoint]

So I got interested enough in this question that I decided to simulate it.

...

Next I generate a random direction for each of 360 projectiles,

Thanks a lot, interesting findings. How did you decide to use 360 pieces of shrapnel? I know there are 360 degrees in a circle, but is it indicative of the amount of steel balls in the casing of an S-mine?

Not trying to be snarky, just interested

[Bulletpoint]

Btw, anyone know what sort of mines the Allies used ? Was there any equivalent to the "jumping" S-mine or was that a uniquely German weapon ?

From what I can find on Wikipedia, the US army developed their own version, based on the S-mine, but only after the war. I guess that they didn't need to invest in mine development at that time, being on the offensive.

http://en.wikipedia.org/wiki/M16_mine

[c3k]

Thanks a lot, interesting findings. How did you decide to use 360 pieces of shrapnel? I know there are 360 degrees in a circle, but is it indicative of the amount of steel balls in the casing of an S-mine?

Not trying to be snarky, just interested

S-mine listed as using 360 ball bearings (some substituted short metal rods). That must've been the reason for the Schweinfurt raids! Less ball bearings for the verdammt s-minen!

Ken

[JasonC]

Bulletpoint - as c3k says, the S-mine contained 360 steel balls, that is where my number of projectiles came from. Now to be sure, there might also be a few additional fragments of the casing large enough and high enough velocity to be additional wounding elements - though the number of those would fall off with range. But I am also ignoring gravity pulling more of the fragments into the ground before they have gone 50 meters etc - mostly because I don't know the velocity distribution for the projectiles. It is still close enough, because the driver is clearly just the uneven coverage and the limited range window for each effective projectile (how long it spends in the right height window).

[John Kettler]

c3k,

Came across your No. 21 while hunting for one of mine. I beg to differ. In the remarkable and moving Penalty Strike, author Alexander Pyl'cyn, formerly an Independent Penal Battalion (ex-officers only) Penal Platoon (later Penal Company) Commander, describes how the platoon in front of him was killed to the man by a single S-Mine laid by the retreating Germans on the dirt road shoulder to slow the Russian advance. "Everyone was killed" is dispositive as far as I'm concerned. This is buttressed by his making no mention whatsoever of medics, and the book has many such references. Would cite the page number, but am moving in a few days and have my library already packed. If the formation, which I want to say was four soldiers wide, occasioning the slightly off the road movement, was arrayed like this, then I can see why such a thing might occur.

http://4.bp.blogspot.com/-_CyU6LGj3jE/Tkv82MAKn4I/AAAAAAAAMo0/cDCH0MuVAFw/s640/Russia+during+world+war+2+12.jpg

Regards,

John Kettler

[John Kettler]

c3k,

If it's the S-Mine 44 described here in TM-E-30-451 Handbook on German Forces, Chapter VIII. Equipment, Section V. Engineer Equipment, 5. Antipersonnel Mines, b S-MINE 44, then it would explain a lot.

"b. S-MINE 44. (1) Description. The S-Mine 44 is an antipersonnel mine of the bounding type similar to the S-mine 35. The igniter well is toward one side of the cover plate, and the height at which the mine explodes is controlled by an internal pull-igniter arrangement. The igniter is the combination push-and-pull type, and its neutralization demands extreme care. The employment of this mine is the same as for the S-mine 35. The lethal range is 22 yards, and the casualty range 110 yards."

Now, referring to that mass of humanity in the photo, imagine an S-Mine 44 going off right next to it. Am sure we'd agree that an entire platoon, whose components are marching administratively practically atop each other and four abreast, would neatly fit into the lethal zone? The mine is right for the period of the book, too, since Ply'cyn fought in Op Bagration.

c3k, ArgusEye and poesel71,

According to this, the "S" is for Sperrmine.

http://www.lonesentry.com/articles/ttt08/german-mine-fields-in-libya.html

"Sperrmine" translates as "blockade mine," and I'd find it very effective in that role, were I the PBI running into it.

http://www.dict.cc/german-english/Sperrmine.html

In game terms, the lethal radius for a single S-Mine of this type is three AS, and the casualty radius is 14 AS! Try putting cookie cutter patterns like that on a CMx2 battlefield and see what it does for maneuver schemes.

Regards,

John Kettler