great mod but one question

[russia almighty]

How was Lino-thorax armor an effective form of armor ? Has there been some experimental archeology to prove that it could take a beating?

[MeinPanzer]

How was Lino-thorax armor an effective form of armor ? Has there been some experimental archeology to prove that it could take a beating?

From "The Effectiveness of Classical Armour" by John Gerson, from Slingshot 102, July 1982. I've quoted the portions relevant to linothorax effectiveness.

The thicknesses of bronze and steel armour required to just stop some ancient weapons have been calculated and are shown in the Table below. The kinetic energies of the weapons were estimated from several factors, such as their weight and range and the performance of modern athletes in tests .

Arrow - radius of 3 mm, energy of 200 joules for 23.5 mm thick bronze or 14.4 mm thick iron.

Small catapult bolt - Radius of 5 mm, energy of 400 joules for 17.0 mm thick or 10.4 mm thick iron.

Javelin - radius of 10 mm, energy of 200 joules for 2.2 mm thick bronze or 1.3 mm thick iron.

Sling-shot - radius of 8 mm, energy of 100 joules for 1.7 mm thick bronze or 1.0 mm thick iron.

The armour thicknesses obtained above are slightly larger than the actual values that would be obtained from the experiment. From 5% to 40% of the projectile's initial kinetic energy will be lost by air resistance, metal-to-metal friction at impact and be deforming the projectile itself. This last factor, which was important in an age in which the sword blades were made of soft-wrought iron, could be minimized by the use of harder materials for weapons. The Greeks' bronze arrowheads contain much more of the hardening element lead than their armour, whcih implies that Greek arrows were intended to be armour-piercing.

....

A missile penetrates padding or other low density materials [i.e. the linen of the linothorax] by pushing material out of its path. This is a momentum transfer process and experiments have shown that the penetrating power of a projectile is proportional to its momentum, rather than its kinetic energy. Because the momentum of a missile of given kinetic energy decreases with lower mass, padded armour stops light projectiles, such as arrows or slingshots, particularly effectively. Padding also offers good protection against sword cuts. The use of the sword as a primary weapon by Romans and Celts may have encourages the late Etruscans' experiments with quilted armour as a substitute for mail.

But woven textile armour and laminates of cloth and glue display a property known as the limiting velocity, which was described by Jaskowski in 1964. If a textile armour is struck by a projectile travelling faster than the limiting velocity (the speed corresponding to the momentum required to pierce it), the projectile will perforate the armour with virtually no loss of kinetic energy.

....

The largest energy that the linen [in a linothorax] can absorb in an impact is 100 joules.

....

At a guess, a long slashing sword could probably dispose of 150 joules, which is twice the energy required to shatter a man's skull. Felt, which was commonly used to line the inside of helmets, is described by the Shock and Vibration Handbook as being too elastic properly to absorb a blow.

This is the only source I have ever found for such information, though I'm sure many reenactors have put linothoraxes to the test in the past.

[russia almighty]

Interesting . I always assumed that the reason lino-thorax armor caught on was the cost factor . Seems like great anti-missle armor but the wearer is screwed if that javelin thrower is in your face with a longsword .

[MeinPanzer]

Interesting . I always assumed that the reason lino-thorax armor caught on was the cost factor . Seems like great anti-missle armor but the wearer is screwed if that javelin thrower is in your face with a longsword .

I think it largely caught on mainly because of the mobility it afforded the wearer, and mobility became more and more highly valued from the 5th century BC right down through the Hellenistic period.

[QwertyMIDX]

One of our team members likes to hack away at reconstructed armor. Maybe he'll stop by and talk about it.

[mcantu]

Those energy amounts seem rather high. They might be correct at the point of launch but not at the range that they would strike a target.

[Eduorius]

I also think the climate must have something to be taken in count when using an armor. The linothorax is lighter and more ventilated than a metal cuirass. What is the purpose of being so well protected if the heat is going to sophocate you at the end. This brings me to a question.

How can a Cataphract (rider and horse) can fight well after a long period of time? The heat must be like a oven in there.

[Philippus Flavius Homovallumus]

Panzer, your numbers look miss-typed you must have some decimal points in the wrong place.

Even a blunt javalin is more effective than an arrow.

Eduorius: I believe it has to do with a number of things:

Training: As someone who has lugged a modern soldiers fighting kit around on a hot summer day all I can say is eventually you get used to it.

Insulation: After a certain point all that felt and blocks in the incoming heat, at which point all you have to worry about is your own body heat, which will build up.

They didn't: Kats only really need one charge, they probably had their helmets off until they were actually fighting, rather like the old Corinthian Hoplites.

[MeinPanzer]

I also think the climate must have something to be taken in count when using an armor. The linothorax is lighter and more ventilated than a metal cuirass. What is the purpose of being so well protected if the heat is going to sophocate you at the end. This brings me to a question.

How can a Cataphract (rider and horse) can fight well after a long period of time? The heat must be like a oven in there.

The Parthian cataphracts at Carrhae may have been wearing furs to alleviate the direct sunlight bearing down on them, though they would probably make the rider just as hot from their insulation of heat...

[McHrozni]

Panzer, your numbers look miss-typed you must have some decimal points in the wrong place.

Even a blunt javalin is more effective than an arrow.

Well, since it is said that momentum is important: G = m*v, I'm inclined to agree. A javelin is so much heavier than an arrow that is is at least greatly unlikley to expect it to have any less momentum. Throwing a javelin at 10 m/s is probably quite easy, but loosing an arrow at 100 m/s is another matter - though this is approximately the top speed recorded at modern bows if I remember correctly.

Were kinetic energy important: W = 1/2 * m * v^2, things would be different.

Lastly, I don't really see how an arrow could pierce 14mm of iron. That's a bit more than half an inch, or a bronze plate an inch thick, if you like using imperial system. Imagine an arrow piercing a church bell - does it seem likely?

McHrozni

[L.C.Cinna]

Eduorius:

There's a reason the Roman word Clibanarius means something like "cooking pot guy" ;)

Kathaphracts couldn't operate for too long. They can be compared to superheavy tanks. They were "transported" to the combat area, mounted and put on the heavy armour right before combat,charged when the proper situation arrived. when the ground is not favourable or they are stopped by infantry they are like sitting ducks really. The use of kataphracts was very limited as Ammianus states.

[MeinPanzer]

Panzer, your numbers look miss-typed you must have some decimal points in the wrong place.

Even a blunt javalin is more effective than an arrow.

Eduorius: I believe it has to do with a number of things:

Training: As someone who has lugged a modern soldiers fighting kit around on a hot summer day all I can say is eventually you get used to it.

Insulation: After a certain point all that felt and blocks in the incoming heat, at which point all you have to worry about is your own body heat, which will build up.

They didn't: Kats only really need one charge, they probably had their helmets off until they were actually fighting, rather like the old Corinthian Hoplites.

No, I checked and those numbers are properly typed. He goes through all the physics for his numbers and cites sources for all his numbers.

[McHrozni]

No, I checked and those numbers are properly typed. He goes through all the physics for his numbers and cites sources for all his numbers.

I have to cast doubts on his methods, then. Arrow historicaly didn't always pierce armor, but if his arrows were correct the first battle in which they couldn't pierce it from range wouldn't take place until 1939.

Medieval plate mail was wearable up until 3mm thickness, more than that was way too heavy to wear. What he is saying is that an acinent arrow could pierce up to five times that.. it really casts the values in doubt.

He also says that an arrow should be able to punch through a regular sized church bell, which I find slightly absurd. Has anyone tested this?

McHrozni

[HumphreysCraig00]

In regards to the Cataphracts, theier riders in the Persian and Sassanid dynastys also performed rigourous physical training, which will have made them more able to cope with the heat as a more fit man will be better able to cope with intense heat than a less fit man.

Also what members of the english recreation group, the hoplites, have found is that when it gets damp, through sweat, or through exposure to moisture/water the glues involved in the manufacture of linothorax lose thier efectiveness and it becomes much less rigid and much softer. I dont know how this effects its ability to resist penetration however.

Arrow - radius of 3 mm, energy of 200 joules for 23.5 mm thick bronze or 14.4 mm thick iron.

What???

So what your saying here (or hes saying whatever) is that Ancient period bronze tipped arrows have comparable penetration to modern 5.56mm FMJ?
I doubt it.

A missile penetrates padding or other low density materials [i.e. the linen of the linothorax] by pushing material out of its path.

Thats also how missiles penetrate High density materials, indeed all materials...

The only other way I can think of is rapid pressurisation leading to instant liquidisation as happens with modern ApDS/HEAT tank rounds...

The use of the sword as a primary weapon by Romans and Celts

From what I know of the period and later periods (I know more about middle ages warfare) the main weapon of the Celt like peoples was the spear, as swords were too expensive for the commoner. Is that right or wrong and if wrong please post evidence

But woven textile armour and laminates of cloth and glue display a property known as the limiting velocity, which was described by Jaskowski in 1964. If a textile armour is struck by a projectile travelling faster than the limiting velocity (the speed corresponding to the momentum required to pierce it), the projectile will perforate the armour with virtually no loss of kinetic energy.

How? If it needs that amount of energy to penetrate, that means it will be lost, no matter what, from my knowledge of physics it cant be any other way? Anyone know what this limiting velocity is and how its supposed to achieve the effects it apparently does.

[McHrozni]

How? If it needs that amount of energy to penetrate, that means it will be lost, no matter what, from my knowledge of physics it cant be any other way? Anyone know what this limiting velocity is and how its supposed to achieve the effects it apparently does.

It is possible that the penetration is more effective at higher speeds. The amount of material it has to push out of the way could be lower.

McHrozni

[Philippus Flavius Homovallumus]

No, I checked and those numbers are properly typed. He goes through all the physics for his numbers and cites sources for all his numbers.

A javalin is will quite happily go straight through mail, or a car door. Those numbers also say an arrow is better than a bolt from a catapult.

Check again.

[fallen851]

You can drive a needle farther into a piece of plastic, than you can a hammer head, even with far more momentum and force.

I'd say those number Panzer posted are fine, remember physics class?

And the classic one, an elephant laying down sideways on your foot wouldn't be as painful as a 300 pound women stepping on your foot with a pair of high heels (using the heel).

[QwertyMIDX]

Sure, but all the things Panzer mentioned (except the sling shot, assuming the author means an ancient catapult) end in a point. While the arrow head is smaller, the comparison between needle v. hammer and arrow v. javelin is not a sound one. It's also pretty clear that if an arrow could pierce a solid inch of bronze with any kind of regularlity ancient armor (which is definatly not an inch of solid bronze) would have been pretty useless, which begs the question, if it was expensive, cumbersome, and offered no real protection, why bother?

[Tuuvi]

I think panzer is right, the reason a javelin has more penetration power is because it is heavier than an arrow. I am into traditional archery and there is a rule for how heavy your arrows need to be for hunting to strike a good balance between speed and penetration. the general rule is to have 10 grains of arrow weight for every pound of draw wieght. So if your bow pulls 50 lbs., your arrows should weigh 500 grains. However if you are hunting a bigger animal than a deer, say a moose of a bear, you might want heavier arrows than that to get enough penetration power to kill the animal.

[MeinPanzer]

A javalin is will quite happily go straight through mail, or a car door. Those numbers also say an arrow is better than a bolt from a catapult.

Check again.

Check it yourself.

[The Persian Cataphract]

I also think the climate must have something to be taken in count when using an armor. The linothorax is lighter and more ventilated than a metal cuirass. What is the purpose of being so well protected if the heat is going to sophocate you at the end. This brings me to a question.

How can a Cataphract (rider and horse) can fight well after a long period of time? The heat must be like a oven in there.

I will elaborate later on this question, but to clarify something Roman authors thought of the Iranian heavy horse as brave though emphasizing their lack of endurance. The feudal structure of the Iranian society was especially helpful as it would provide squires and servants (Bondsmen) to carry and to care for the noble's armour. Partly, this is why Parthia never was able to follow through with a siege, but instead followed a a season-based calendar, choosing the most suitable timing to mount a swift, hard-hitting attack, and this reflects the Parthian tactics in combat as well.

This is why I still like RTR, they made the cataphracts a true meat-grinder as well as an element of challenge. Charging head-on was usually foolish, and getting bogged down was down-rightly suicidal, their ambling pace and low stamina made it harder to flank, but this paid off, because once the cataphracts charge where the enemy is unprepared, little can stop them

[McHrozni]

Check it yourself.

I think I found the sticking point. Here it is:
Arrow: 3mm radius

Sure, the shaft of an arrow is around 3mm thick. But the head of the arrow is usually wider, even a bodkin point would be almost 10mm thick (3/8 of an inch, slightly more than 9,5mm). While it certanly is possible to make a smaller arrowhead, those won't do much more than pierce the armor either - the lower the radius (calibre) the smaller the chance of a serious wound being inflicted. I'd say that the bodkin points were close to the minimum radius required to make the wounds they inflicted serious. The square of the radius is in the equation of the needed thickness, and this would correspond to approximately 1/10th penetration capacity - a 1,5mm thick steel plate should defeat the projectile.

This would also mean that an arrow would have a penetration power much closer to the value of a javelin, noted below - same energy, similar radius.

Secondly, this value is probably calculated for a heavy bow at pont blank range.

Lastly, this would fit well with anecdotal evidence of plate mail withstanding voleys of arrows and making archers obsolete without requiring that armor being made of as-yet-unknown high strength low weight materials.

It's called critical thinking. Again, how many bows will punch straight through a church bell?

McHrozni

[Philippus Flavius Homovallumus]

Yes, there's also the fact that with the exception of the slingshot all the projectiles are pointed.

The amount of presure applied to the armour at the Point of Impact is what determins the penatrating ability. Once the armour buckles and deforms job is mostly done.

A javalin has a higher force because of it's much greater mass but it has a very similar PoI and therefore a greater penatrating ability.

[Kugutsu]

Theres two factors which have an effect: the pressure and the momentum.

Pressure can be worked out by: Pressure (N/m2) = Force (N) / Area (m2)

Momentum (or kinetic energy) depends on the speed and the weight of the object, the speed being more important: Kinetic Energy (J) = 1/2 mass (kg) x speed2 (m/s2)

Linking the two is a bit tricky, as you need to divide the kinetic energy by the distance over which the force has been applied to work out the force, however given the mass, speed, area of point and distance from when it hits to when it stops (thats the tricky bit) it should be possible to work out which projectiles are best...

[McHrozni]

Theres two factors which have an effect: the pressure and the momentum.

Pressure can be worked out by: Pressure (N/m2) = Force (N) / Area (m2)

Momentum (or kinetic energy) depends on the speed and the weight of the object, the speed being more important: Kinetic Energy (J) = 1/2 mass (kg) x speed2 (m/s2)

Linking the two is a bit tricky, as you need to divide the kinetic energy by the distance over which the force has been applied to work out the force, however given the mass, speed, area of point and distance from when it hits to when it stops (thats the tricky bit) it should be possible to work out which projectiles are best...

There is another, the differance between the materials - hardness and toughness, or however they're called in english. If the projectile is softer than the armor, it could buckle at impact, causing it to loose penetrating power or even deflect altogether, even if it otherwise could penetrate.

Secondly, a structuraly stronger material (steel vs bronze, for example) will resist being pushed out of the way with greater force, therefore diminish the penetration. This is covered to some extent, by providing two values, one for bronze armor and another for steel armor, but neither is by any stretch of imagination a single metal, but a family of different metals.

The estimates there are, at best, rough estimates. But the arrow is still way off the mark.

Overall, the simpliest way to figure it out would be to build a set of armor you were trying to test, and an authentic set of weapons, and start testing. You'll have to do that anyway, if you intend to verify your model. I imagine that there are fairly accurate models in existance, but this wasn't one of them

McHrozni

[Philippus Flavius Homovallumus]

There's also the shape of the projectile. Most of these weapons have cutting heads, which will litterally slice through armour once that little hole is made on impact. Bodkin arrows mark the high point of that technology.