Optimal size for a soldier?

[KraytKing]

I feel this is most appropriate to sci-fi, but it also has elements of fantasy.


Assuming you get to choose, how big do you want your infantry to be? Warhammer 40k leans towards "bigger is better," with the Space Marines and Orks both. The physiological issues with the Space Marines are well known; humans aren't supposed to be that big. And while a bigger soldier can carry more armor, bigger weapons, and is generally more survivable, their cargo proportional to their mass decreases. Star Wars is actually reasonable here, with clone troopers being 6'2"--tall, certainly, but within the bounds of normal human variation.

Obviously, context is important. Let the discussion have three objectives: the best size for a pre-industrial army, the best for gunmen from arquebusiers to the Great War, and the best for the modern era into the future.

[Patroklos]

I'd say whatever bodymass is sustainable based on the logistics of the setting (armies march on their stomach) while having the strength to adequately handle the primary weaponry of the time to include getting it to the enemy. This would vary widly even within the timeframes given.

[Lord Revan]

Wait Clone Troopers are 6'2 cm, I thought they were under 6', they don't seem as tall as Anakin pre-armor and IIRC pre-armor anything was 185 cm or so.

I checked and the height for Jango Fett is given as 183 cm (in Wookiepedia sure but it's the best source I got atm) which would be close to 6' then 6'2. 6 feet being about 182 cm or so (182,88 cm exactly based on the defination of "feet" I got but between 182 cm and 183 cm is "close enough")

As for the OP it depends but I'd say between 170 cm and 190 cm would be optimal (yes it's quite a range but there's other factors to consider) when talking about humans, but even then it depends on the role those troopers are intended, for examples tank crews might be smaller to better fix the vehicles, while shock infantry might be bigger to better deliver the shock effect to the enemy.

[Gunhead]

Having smaller tank crewmen was to some extent implemented by russians and it's a minor space / weight save at best. The real big thing is how many crewmembers are in the vehicle in the first place. For the most part the size of your fighters is a moot point unless where going to ridiculous extremes with it. All battles are and have been about getting there with more stuff so endurance is far more desirable than being a hulking muscle man.

-Gunhead

[LadyTevar]

Battletech went to the extremes with the Clans. Mech-pilots were average 175-180cm. Aerospace fighter pilots were shorter and lighter, probably 166cm or smaller. Elementals were bulked up as much as humanly possible: 190cm+ even for the females.

[Captain Seafort]

Another datapoint for pre-industrial infantry - the Numenoreans. Their average height was something over 6' 4", with the tallest known individual being almost 8', and (as Gunhead notes the importance of endurance) capable of long marches with full kit (about 25 miles a day normally, 35+ forced).

[KraytKing]

You might be thinking a little too limited here. Can't a soldier three or four feet tall drive a tank just as well as regular sized men? Carry a gun that can kill bigger guys just as dead? And he's more concealable, and takes less logistical load. If you're expected to fight enemies with a sword, however, you may be troubled by such small stature, but even so shortness can be desirable for counteracting cavalry.

If an option were to field heavy infantry standing ten feet tall and wielding swords bigger than most men, would it benefit those who tried it?

[Jub]

The best soldier will always boil down to far more factors than size and often even their ability to fight will only be of limited concern. The qualities you actually need in a soldier are:

1) Availablity: The soldier you can actually use is worth an infinite number of perfect but unobtainable soldiers.
2) Affordability: The soldier and their gear and training cannot cost too much or your ability to field enough numbers will be compromised.

Once you get beyond those basic requirements you start looking at the next level:

3) Reliability: Soldiers that defect or flee aren't exactly useful.
4) Expendibility: The best soldier is one which doesn't raise undue alarm among the population when they become a casualty.

Beyond that you can look at:

5) Trainability: The soldier you can teach is a valuable asset indeed.
6) Retainability: Keeping soldiers beyond a single term of service is how you build a military tradition.

Finally you get the luxary of:

7) Ability: Both physical and mental appitude fall here.

[Gunhead]

You might be thinking a little too limited here. Can't a soldier three or four feet tall drive a tank just as well as regular sized men? Carry a gun that can kill bigger guys just as dead? And he's more concealable, and takes less logistical load.

This is an example of overspecialization for no or very limited gains with serious drawbacks. 90-120cm vehicle crews only make sense if I designed the vehicle to be operated by such. This basically means a normal 175cm person couldn't operate it or even fit inside. This applies vice versa too, a 120cm tall person would struggle to operate any and all armored vehicles in service today and in many ways just wouldn't be able to. Things like seeing out would cause serious issues for example and good luck with those 20kg shells. Things get even more fucky when your 120cm crew gets the funtimes of doing basic vehicle maintenance as the vehicle would still be for all points and purposes the same size. Engines, weapons, fuel, ammunition and all the internal systems take the same amount of space and weight the same, regardless of the size of the operator. As basic infrantry, well sure.. they're more concealable. Now take this 40kg pack + 4kg of gun and lug it 40-50km that way and once there entrench, oh and you have 8 hours to do it. Better get going. The problems starts to come into focus.
Smaller size of the personnel does pretty much fuck all to lessen the logistical load when all the stuff you need to fight still weights the same and takes the same amount of space.

If you're expected to fight enemies with a sword, however, you may be troubled by such small stature, but even so shortness can be desirable for counteracting cavalry.

Yea... no. While again I could easily conjure a scenario where small stature would confer advantages, they all fall apart when your teeny tiny anti-cavalry force gets mauled by regular infantry coming to smack them about.

If an option were to field heavy infantry standing ten feet tall and wielding swords bigger than most men, would it benefit those who tried it?

Sure, if you can do it cost effectively but again it's, overall, probably a poor trade off. I also wouldn't trade numerical superiority for this. Bear in mind that 300cm tall man would weight by himself around 220-240kg. Now slap on that ... about 60-80kg of armor and weaponry and we're in the 300kg range. If I disregard all other considerations and assume I could get like 1000 of such fighters, I'd still be looking at the logistical funtimes of lugging 60-80 tons of stuff around just to gear them for combat. No normal horse would reasonably carry them so I'd have specialized infantry with a logistical trail as long as the wall of china. Again, problems start to appear very quickly.

-Gunhead

[bilateralrope]

Warhammer 40k leans towards "bigger is better," with the Space Marines and Orks both.

Neither are good examples to use here.

The Imperium doesn't have many Space Marines. Only approximately 1 million for the entire galaxy. The vast majority of fighting is done by the Imperial Guard, who are just regular humans.

As for Orks, they all fight. The ones that don't die keep growing.

I checked and the height for Jango Fett is given as 183 cm (in Wookiepedia sure but it's the best source I got atm) which would be close to 6' then 6'2. 6 feet being about 182 cm or so (182,88 cm exactly based on the defination of "feet" I got but between 182 cm and 183 cm is "close enough")

IMDB gives a height of 5' 7½" (1.71 m) for Temuera Morrison.

[Sky Captain]

I suspect in a pre industrial setting soldiers of different sizes would be more useful than after industrial revolution when war become more mechanized and involved much greater logistical trail to support army in a field. Equipment optimized for say 120cm soldiers would be poorly suited or even unusable for normal size humans making logistics more complex. A tank optimized for 120 cm crew may be slightly smaller presenting a little less target profile and that's it probably fairly marginal advantage at a cost of more complicated logistics requiring highly special crew.

Sure, if you can do it cost effectively but again it's, overall, probably a poor trade off. I also wouldn't trade numerical superiority for this. Bear in mind that 300cm tall man would weight by himself around 220-240kg. Now slap on that ... about 60-80kg of armor and weaponry and we're in the 300kg range. If I disregard all other considerations and assume I could get like 1000 of such fighters, I'd still be looking at the logistical funtimes of lugging 60-80 tons of stuff around just to gear them for combat. No normal horse would reasonably carry them so I'd have specialized infantry with a logistical trail as long as the wall of china. Again, problems start to appear very quickly.

Actually I think in a pre industrial setting there would be more benefits from giant super soldiers than in industrial setting where mass production of standardized equipment won wars.
In a medieval setting there were no factory production lines, weapons and armor were hand made by craftsmen so having to make a batch of bigger armor suits, swords and bows may not be that big of a hurdle compared to having a different production line in a factory supplying non standard size equipment. What if one 3 m super soldier in a battlefield is worth on average 5 normal soldiers. There could even be a benefit. 1 super soldier would require less resources to support than 5 normal soldiers. Making a bigger sword or bow would be maybe 2 times as labor intensive as one normal size, same goes for armor suits. If my craftsmen can equip 3 super soldiers in the same time it would take to equip 6 normal soldiers, but 3 super soldiers are expected to be worth 15 normal soldiers then there is major advantage.

[Solauren]

Another factor to consider is speed in combat.

Your 6'2 fighter is useless if my 4'6 troops are so fast and agile and skilled he can't hit them.

Your muskets are useless if my troops are so fast that after your first volley, they've covered lethal range and are now stabbing you to death.

Your high end tank is useless if my troops are so fast they just avoid the shells, run up to your tank, and start boarding it/taking it apart.

Your hordes of 4'6 super ninja are useless when my dragon flies overhead and breaths fire on them. But he's useless when your suborbital starfighter snipers it from 6 miles up.

In other words, it all matters in context of what you are fighting.

[madd0ct0r]

Are the soldiers manufactured for war?
Are you in a decade long total war?
If no, then you are drawing from the general population who will either be the usual Gaussian bell curve from gene interaction, a mixed size population due to roles and nutrition (like army ants), or extremely homogeneous because most species don't vary in size the way humans do.

I've read sci-fi where humans have mostly offloaded their brains to the cloud, so bodies are reduced to a few inches high. Other stories were spacers had adopted chimp like size, like feet

[Lord Revan]

1) Availablity: The soldier you can actually use is worth an infinite number of perfect but unobtainable soldiers.

Also if we stay within what's realistic for humans even if you can obtain your "perfect" soldiers but you obtain only 10 of them while your opponent can field an army of 10 000 of "good enough" troops.

this is why most modern armies recruit from the general population rather then trying to create a specialized "warrior class" of perfect soldiers, this way you get the largest amount of suitable recruits while having the least amount of logistical burden.

Also for important parts of your logistics pretty much all adults "cost" the same and the differences in build don't create big savings.

[Simon_Jester]

You might be thinking a little too limited here. Can't a soldier three or four feet tall drive a tank just as well as regular sized men?

Not necessarily. Operating a tank (and maintaining your tank) requires you to do things like remove bolts, lift up big steel hatches, push controls and operate mechanisms that may get stuck. A certain amount of grunt to handle the machinery becomes kind of a necessity when you're working with a tank that weighs dozens of tons.

It's probably possible to deal with this kind of constraint from an engineering standpoint, mind you- but it's not trivial. For example, can your three foot tall loader load 120mm artillery rounds into a tank, when the rounds probably weigh more than he does? Likely not.

Look up a Youtube channel called "The Chieftain," and look for some of the "Inside the Hatch" videos he does; you'll get a good exposure to the practical human aspects of operating various WWII (mostly WWII) tanks. This includes a lot of stuff people often don't think of when superficially considering warfare, like "do people have enough room to sit in a reasonably comfortable position and work smoothly" and "will you be able to get out if the tank is on fire" and "how much of a pain in the ass is it to maintain this feature?" It turns out that these factors can have a lot to do with how well a tank performs, as much or more than things like how much armor plate the tank carries. After all, getting in the first shot because your tank commander could concentrate on spotting the enemy and coordinating the tank's movements often means you don't have to try to withstand the enemy's first shot.

Carry a gun that can kill bigger guys just as dead? And he's more concealable, and takes less logistical load

...Most battlefield environments where a five foot tall man can hide are also environments where a six foot tall man can hide; the marginal advantages are likely to be offset by disadvantages such as "cannot carry as large a weight of ammunition" or "cannot carry a full kit of tools."

By the time you get down to a 3-4 foot soldier, you reach a point where the soldier may barely be able to physically operate the size of infantry weapons an ordinary human could. Instead they have to settle for much smaller-caliber or lower-velocity ammunition, which means greatly reduced range and stopping power.

If you're expected to fight enemies with a sword, however, you may be troubled by such small stature, but even so shortness can be desirable for counteracting cavalry.

Uh, not really? I mean, it's not that hard for cavalry to carry weapons capable of skewering a short opponent; a man sitting on a horse isn't that high off the ground or he wouldn't be able to climb on the horse's back in the first place.

If an option were to field heavy infantry standing ten feet tall and wielding swords bigger than most men, would it benefit those who tried it?

Almost certainly, unless we bring in the realistic physical consequences of gigantism (which is why nine foot tall men do not live long in real life). There's a reason why, barring freakish outlier conditions, a ten year old child can't realistically win a fistfight with a grown man. Everything is against the kid. The physical disparities between typical humans and your ten-footers would be comparable.

Another factor to consider is speed in combat.

Your 6'2 fighter is useless if my 4'6 troops are so fast and agile and skilled he can't hit them.

Your muskets are useless if my troops are so fast that after your first volley, they've covered lethal range and are now stabbing you to death.

Your high end tank is useless if my troops are so fast they just avoid the shells, run up to your tank, and start boarding it/taking it apart.

Your hordes of 4'6 super ninja are useless when my dragon flies overhead and breaths fire on them. But he's useless when your suborbital starfighter snipers it from 6 miles up.

In other words, it all matters in context of what you are fighting.

Yeah, but most of the time we're not imagining soldiers who have comic book abilities to just Bullet Time dodge bullets and shells, or sprint across an open field at sixty miles an hour.

Some reasonable degree of "by default, default assumptions hold true" is a practical necessity.

[Broomstick]

Humans evolved to land mostly within a certain size range. Outliers tend to have health issues of one sort or another, so I would first argue that you're best off recruiting soldiers in the middle-range of normal as they will tend to be the healthiest humans, or maybe slightly (but only slightly) above average.

For pre-industrial fighting bigger was usually better... up to a point. If you're using muscle power then all other things being equal the bigger guy with more mass and muscle is most likely to win. Then it comes down to numbers - you'll do better fielding 1,000 merely average men vs. 10 really big guys.

Once technology comes into play the scenario changes a bit for marginal cases. I recall something about the Germans having a height maximum for early u-boats. Initially, for air combat, lighter-weight pilots would have some advantage but with modern aircraft that's no longer relevant, the amount of power available more than compensates for slight weight differences. Outer space is probably the only place smaller size might be an advantage (uses fewer consumable resources and fits into smaller spaces, or the same space more easily) but only up to a point because, again, below a certain size there's usually some health issue that's going to counter-balance any small advantage.

[KraytKing]

The responses so far are excellent and illuminating, thank you. I am aware of the issues caused by extreme gigantism or dwarfism, but for now let's set those aside. Either through magic or science, those issues have been solved. The question is more along the lines of "IF you're designing an army from scratch, because you have magic or cloning labs or whatever, what size do you want?" Of course, those of you who have pointed out that availability is the more important factor, yes I am in agreement.

If you're expected to fight enemies with a sword, however, you may be troubled by such small stature, but even so shortness can be desirable for counteracting cavalry.

Uh, not really? I mean, it's not that hard for cavalry to carry weapons capable of skewering a short opponent; a man sitting on a horse isn't that high off the ground or he wouldn't be able to climb on the horse's back in the first place.

Ah, maybe not THAT small. I was thinking more along the lines that a shield wall of powerfully built, four foot tall heavy infantry is going to be better at absorbing the impact of a cavalry charge. One on one, the shortness isn't going to be significant, as you say. Lower center of gravity, however, makes for an opponent more difficult to topple.

[Jub]

The responses so far are excellent and illuminating, thank you. I am aware of the issues caused by extreme gigantism or dwarfism, but for now let's set those aside. Either through magic or science, those issues have been solved. The question is more along the lines of "IF you're designing an army from scratch, because you have magic or cloning labs or whatever, what size do you want?" Of course, those of you who have pointed out that availability is the more important factor, yes I am in agreement.

In such a setting equipment is going to matter far more than the size of the soldier using it. So you'd first need to build out the vehicles, weapons, gear, etc. and then figure out if optimizing your soldiers to hyper specialized roles is worth the cost, time, and effort to create several new strains of clones. Also, are these clones just bodies that you put the minds of citizens in or are you creating an army of meat robots just to fight and die for whichever government is in power? That question and what you do with the clone soldiers that reach the end of their useful soldiering years is way more interesting that optimizing for size.

[LadyTevar]

Also, if you're going for pre-industrial, remember that REACH is a serious advantage. A 6ft tall man will have a better reach with the average 3ft sword than a 5.5ft man. Plus, the 6footer will have a really nasty downswing.

Of course, I'm basing this on SCA combat, which is more Tourney than Melee for the most point.

[bilateralrope]

Your 6'2 fighter is useless if my 4'6 troops are so fast and agile and skilled he can't hit them.

When we are talking pre-gunpowder warfare, how often was there somewhere to dodge to ?

Because my impression of such warfare is a lot of tight troop formations. Move aside to dodge the blow from one soldier and you'll get hit by the blow of the soldier beside him. Or maybe find that one of your allies is in the way.

[Solauren]

Also, if you're going for pre-industrial, remember that REACH is a serious advantage. A 6ft tall man will have a better reach with the average 3ft sword than a 5.5ft man. Plus, the 6footer will have a really nasty downswing.

Of course, I'm basing this on SCA combat, which is more Tourney than Melee for the most point.

Melee combat reach is bad.
Why?
Recovery time.

It takes longer for a 6 footer with a large sword to swing, then it does a gut with a longsword or even short swords.
And in the case of mass combat, that's really bad. Cause while your 6 foot monster is trying to hit one guy, three more swarmed him.

[Gunhead]

Melee combat reach is bad.
Why?
Recovery time.

It takes longer for a 6 footer with a large sword to swing, then it does a gut with a longsword or even short swords.
And in the case of mass combat, that's really bad. Cause while your 6 foot monster is trying to hit one guy, three more swarmed him.

What are you smoking? Spears and polearms of various types were the staple of combat right up to the mass adoption of firearms. In mass combat recovery time becomes unimportant for the very fact that it's a group effort. It would be hilarious to see hobbits try to "swarm" a tercio. By hilarious I mean they would get butchered before they could land blow one, hell any force armed with only swords would have a bad time with this.
While recovery time is an important part of melee fighting, it's not the end of all things and is more a factor in single combat where you have to time your blows so you don't leave yourself open to counters. All and all if we go into single combat, that's a whole different kettle of fish because it's far more influenced by individual weapon and armor choices, with massively more emphasis on individual skill.

Overall, there seems to be a misconception in this thread what was the deciding factor in medieval battles. If we look at historical data we have, causing more casualties is beneficial yes but unless you can bump it up to significantly more, like 30-50% more, battles would still be decided by morale and maneuver. If I can effectively flank the enemy, it will cause them to rout and this is what ends the battle.

-Gunhead

[Gunhead]

Actually I think in a pre industrial setting there would be more benefits from giant super soldiers than in industrial setting where mass production of standardized equipment won wars.
In a medieval setting there were no factory production lines, weapons and armor were hand made by craftsmen so having to make a batch of bigger armor suits, swords and bows may not be that big of a hurdle compared to having a different production line in a factory supplying non standard size equipment. What if one 3 m super soldier in a battlefield is worth on average 5 normal soldiers. There could even be a benefit. 1 super soldier would require less resources to support than 5 normal soldiers. Making a bigger sword or bow would be maybe 2 times as labor intensive as one normal size, same goes for armor suits. If my craftsmen can equip 3 super soldiers in the same time it would take to equip 6 normal soldiers, but 3 super soldiers are expected to be worth 15 normal soldiers then there is major advantage.

That's a whole bunch of buts and ifs. You're seriously underestimating the manufacturing difficulties when it comes to making bigger weapons, which I find would be counterproductive anyway, but fine lets assume this can be done and we end up with this 1 to 5 ratio of relative battlefield worth.

Now you get 1000 troops and I get 5000. This means I can do things like troop dispersal, threaten your flanks and generally I'm more free to maneuver because I have more guys to play around with. You cannot disperse your force because if you do, you're risking being flanked or surrounded which basically means you're not going to have a good day. If I break my force into five parts, 1000 each, in order to achieve superiority over them you'd have to commit more than 1/4 of your force to achieve superiority on paper, probably closer to 1/2 because you have to win quickly before I flank and spank you. Now if you block my flanking move with your 2nd half, I still have 3000 troops to play with and all of yours are now engaged.

This is of course highly speculative and naturally there's terrain, weather, troop condition and so forth to consider. I'm just using this to illustrate that numbers have a quality of their own when it comes to fighting and which is why this "oh my guys hit moar harder" is not nearly as much of a game changer as people tend to think.

-Gunhead

[Sky Captain]

Actually I think in a pre industrial setting there would be more benefits from giant super soldiers than in industrial setting where mass production of standardized equipment won wars.
In a medieval setting there were no factory production lines, weapons and armor were hand made by craftsmen so having to make a batch of bigger armor suits, swords and bows may not be that big of a hurdle compared to having a different production line in a factory supplying non standard size equipment. What if one 3 m super soldier in a battlefield is worth on average 5 normal soldiers. There could even be a benefit. 1 super soldier would require less resources to support than 5 normal soldiers. Making a bigger sword or bow would be maybe 2 times as labor intensive as one normal size, same goes for armor suits. If my craftsmen can equip 3 super soldiers in the same time it would take to equip 6 normal soldiers, but 3 super soldiers are expected to be worth 15 normal soldiers then there is major advantage.

That's a whole bunch of buts and ifs. You're seriously underestimating the manufacturing difficulties when it comes to making bigger weapons, which I find would be counterproductive anyway, but fine lets assume this can be done and we end up with this 1 to 5 ratio of relative battlefield worth.

Now you get 1000 troops and I get 5000. This means I can do things like troop dispersal, threaten your flanks and generally I'm more free to maneuver because I have more guys to play around with. You cannot disperse your force because if you do, you're risking being flanked or surrounded which basically means you're not going to have a good day. If I break my force into five parts, 1000 each, in order to achieve superiority over them you'd have to commit more than 1/4 of your force to achieve superiority on paper, probably closer to 1/2 because you have to win quickly before I flank and spank you. Now if you block my flanking move with your 2nd half, I still have 3000 troops to play with and all of yours are now engaged.

This is of course highly speculative and naturally there's terrain, weather, troop condition and so forth to consider. I'm just using this to illustrate that numbers have a quality of their own when it comes to fighting and which is why this "oh my guys hit moar harder" is not nearly as much of a game changer as people tend to think.

-Gunhead

Sure, numbers are important and there would be situations where army of giants would be at disadvantage due to terrain or weather conditions when employed against numerically superior normal army . However if it were possible to create such warriors by some sort of magic during Medieval or Ancient period I'm fairly sure it would have been done. There is also morale factor to consider. Enemy troops may just loose morale and run if charged by 3 m tall giants even if on paper they would be able to defeat attacking force. Giants could be useful as elite shock troops. If used correctly they could be pretty big force multiplier.

Granted this assumes there is no significant drawbacks somewhere else. If for the cost of creating one super soldier you could train and equip 50 normal soldiers it is unlikely to be worth the cost. But let's say we have two opposing Medieval armies one has 50 000 normal soldiers other has 40 000 normal soldiers and an elite force of 1000 3m super soldiers. Both are led by reasonably competent officers. If used skillfully super soldiers could be deciding factor like well timed cavalry charge.

This would be more realistic situation than small army of giants only vs big army of normal humans. Even if you had professional elite force of giants if serious war started you would also draft soldiers from general population of normal humans to have maximum advantage.

If we look historically there is Medieval longbowmen that were trained for years specifically to use longbow efficiently up to a point to have notable skeleton deformations so there is actual historical precedent of highly specialized soldiers.

Humans evolved to land mostly within a certain size range. Outliers tend to have health issues of one sort or another, so I would first argue that you're best off recruiting soldiers in the middle-range of normal as they will tend to be the healthiest humans, or maybe slightly (but only slightly) above average.

For pre-industrial fighting bigger was usually better... up to a point. If you're using muscle power then all other things being equal the bigger guy with more mass and muscle is most likely to win. Then it comes down to numbers - you'll do better fielding 1,000 merely average men vs. 10 really big guys.

I think for this discussion we must assume some kind of magic to grow soldiers of desired size that also solves problems of gigantism. Otherwise this whole premise quickly falls apart.

[Lord Revan]

Something we should remember is that regardless of their size these soldiers are gonna have to fight in structures made for the general population so having them be much larger or smaller then general population will cause issues since general population is gonna build structures fit for them, not for your special elite military force (unless you make it a law that structures have to be built with your elite soldiers in mind but enforcing that might end being so costly that it'll eat up any savings you could have made).

For example those dwarf ninjas are gonna have issues when they reach a door that has latch too high for them to reach and that's too strong to be easily bashed open.

Same with the WH40K Space Marines would have issues in rooms that aren't built for people who are 8+ feet tall and and 3 feet wide if not wider.