I read a lot. (Does that surprise anyone?) And most of the fiction I read is either fantasy, sci-fi, historical, or some combination of the above. All of those genres frequently involve armed conflict, and military action is one of those things that it is very easy to get wrong. I have a great deal of respect for books and I try to treat them well, but when Hiro Protagonist and his group of brave souls are all sent off on Operation Certain Death it gets difficult to restrain the urge to throw it across the room.
To be fair, it is difficult to get the details right… or at least right enough to be compelling. Most people don’t really grasp what is involved in fighting a battle, to say nothing of a war. And one of the most underappreciated aspects is the logistics involved in fielding and supplying military forces. Logistics is not glamorous, but it is essential. So in this article I’ll be taking you through a worked example of something I have direct familiarity with: an artillery battery in action.
A quick word before we get started: I’m going to be talking about modern artillery, because that’s what I’m familiar with. But more or less the same logistics considerations will apply for shifting any military unit with similar quantities of personnel and equipment, regardless of era and technology. Where reasonably practical, I’ll look at the options in different settings.
Now let’s look at the basics. We’re talking about a modern light artillery unit equipped with 105mm guns. This isn’t the heaviest artillery available, or even the calibre most commonly used. It is, however, directly comparable with gunpowder weapons throughout the ages, and weapons of similar dimensions have appeared in conflicts ever since cannons became widespread.
If you’re looking at settings without gunpowder weapons however, then things change a little. Heavy siege engines – catapults, trebuchet, etc. – were often made where they were needed. All you need for them are timber and tools, and this describes most of the world for a good chunk of history. There’s a reason engineers and artillery have a close relationship! The non-wooden parts would be carried in the unit’s baggage train, and the Romans used this method for some of their artillery as well. But this only applies to siege weaponry.
Field artillery (what armies use when they are manoeuvring and fighting each other) can’t usually be made up on the spot, so that had to be brought along more or less complete. The usual method was to either put it in or mount it on a cart. Some field artillery could be taken apart and carried on mules, oxen, or – if you were desperate – the backs of some of your soldiers, but that did make it slower to bring into action. Anyway, back to the modern day.
This hypothetical artillery battery is equipped six L118 Light Guns (yes, it should probably be eight… but real-world military units are never at full strength). The L118 is perhaps the best 105mm artillery piece in the world today. It is extremely accurate, capable of dropping shells within more or less the same crater from 18 kilometres away. A standard contact-fused high explosive shell has a lethal zone of up to 100m and can throw fragments much further, so it doesn’t take many of those landing nearby to really ruin someone’s day.
The shells themselves weigh 15kg in their packing containers, and a good crew can fire as many as eight shells per minute. If you want to get a fire mission off quickly and move to avoid counterbattery fire, that is exactly what they would do. A more practical sustained rate of fire, however, is one shell per minute.
So let’s start with some numbers: six guns, each weighing 2 tonnes and about 9m long in firing position. A basic load of ammuntion per gun is about 40 or 50 shells, which might or might not be enough for a day of intermittent firing – let’s call that another 1000kg per gun of ammunition, tools, and maintenance supplies. Then there’s the seven-person gun crew along with their personal weapons and equipment. Perhaps another tonne there. How do you get all this gear to where you need it?
The usual method is to use a truck. When I was in the army we used a version with a 2.5 tonne capacity to tow the gun and carry the crew, along with their personal gear and the essential tools for using the gun. Another couple of trucks would carry the basic ammo load for the battery and drop each gun’s allocation off to them once the battery arrived at its gun position.
Self-propelled artillery – where the gun is built into the vehicle that carries it – is much quicker to bring into action, and makes it easier to avoid counterbattery fire also. It is more expensive and difficult to keep running, but the advantages are worth it for an army that can afford them. Futuristic military forces might have nothing else.
Back in the past, your only option is horses (or the local equivalent thereof – maybe your setting has dogs, emus, or giant hamsters; I ain’t judging.) Oxen are powerful but too slow to really keep up with an army on the move. A 2 tonne load like the L118 would require a minimum of eight horses for sustained movement, and then you need perhaps four more to move the ammunition, gear, and so on for each gun. You can see why it was important to look after them.
By this point we’re up to eight trucks just to move the guns, crews and first-line ammunition. But wait, there’s more! Modern artillery needs a command post. This is the communication and calculation centre. It’s where calls for fire arrive, get turned into directions for how to aim the guns in order to hit the target(s), and are passed on to the gun crews. This needs a minimum of eight people if you want it running around the clock.
So there’s at least another truck’s worth of people and gear for this, and you’re better off with two. Futuristic artillery might have computers built into the guns which can handle all this; historical artillery didn’t shoot at anything it couldn’t see so it didn’t need it.
But you also need a headquarters element to keep track of everything and everyone, arrange supplies and repairs, and do all the other umpty-hundred other tasks. Repairs will need at least two specialists and a lot of heavy and expensive tools; supply needs an overworked quartermaster and a couple of equally-harried assistants; communication needs between two and four signallers or couriers; and then there’s the battery commander and his assistants. Count on at least two more trucks for them, plus three or four jeeps (or whatever you’re using).
And we’re not finished yet. The command post needs someone to tell it where the targets are. Other military units nearby can do that if they have the training and equipment, but there’s no substitute for having your own specialists going out and locating targets. FO (Forward Observer) parties can be quite small – perhaps four people – but they have to cover a lot of ground. You probably want a minimum of two of them, each with a jeep or something similar. Once again, futuristic and historical artillery probably don’t need to worry about this.
Been keeping track of the numbers? So far we’re up to:
- 6 guns
- 70 people
- 12 trucks
- 6 jeeps
That is the BARE MINIMUM to have an effective artillery battery. If you’re using horses or other animals, you also need people to look after them (and you might have more horses than people). That is also not including any attachments – engineer support, air defences, sensors and locating equipment, and so on. You could easily end up with over 100 people. Hopefully the scale of the problem is starting to become apparent.
So you have your 70 people and all the other equipment for an artillery battery, they’re all set up and ready to go. Grand. How do you keep them in fighting condition?
First, food and water: each person will consume about 2kg of food per day, the same in water, and another 1kg or so in other stores (batteries, electrical tape, pencils, sunscreen and chapstick – don’t laugh, sunstroke is NOT a joke – and so on). Figure on 5kg per person per day all up in a temperate climate. Horses will go through about five times that, call it 25kg per horse per day. Just for people, we’re looking at 350kgs per day of stores.
The fuel tank on each truck is at least 200 litres, and if the battery is moving around a lot it could go through half of that every day. Let’s say another 100kgs per day per vehicle (jeeps burn less fuel per km travelled, but they get used a lot more). 1800kgs per day of fuel.
Ammunition is a different problem. A quick fire mission might only need 20 shells or so in total, high-value or large targets might need more than 50. But that is for a quick ‘stonk’, not an ongoing bombardment. If you’re bombarding something seriously, then each gun will fire about one shell per minute. That’s 360 shells per hour for the battery as a whole, and the gun crews can keep this up all day (it is possible to sleep through an outgoing fire mission if you’re tired enough, I’ve done it myself). You quickly get into the situation where you need a more or less constant convoy of vehicles bringing ammunition to the guns. That means a railway line or lots of trucks, horses will not be able to keep up with the sheer quantity of ammunition required.
These days large-scale bombardments are unusual, but keep in mind that the further back in time you go, the more likely they are to happen. For now, let’s work on an average of 50 shells fired per gun per day. For 6 guns, that’s 4500kg of ammunition every day.
All up, we’re looking at just over 6.5 tonnes of supplies every day to keep the battery operational.
Historical artillery gets an advantage here – horses etc. may eat a lot but they don’t need fuel. Artillery of earlier periods is also much less fussy about the ammunition it uses too. Finding rocks for catapults to hurl isn’t too hard. Gunpowder weapons do need gunpowder, but captured enemy stocks will do just fine – they can shoot suitably shaped rocks as projectiles, and in fact the earliest guns usually did. But someone still has to go out and find this stuff, then get it back to the battery. We’re still talking tonnes of supplies every day. That means much more manpower, even if the stores are free for the taking. If they’re not, you will need to persuade whoever has them to give them up.
Historical armies were not always polite about this, which is one reason an army arriving in the neighbourhood was a disaster for everyone living nearby. No matter if they were friendly or not, they would still eat everything and cut down trees for firewood. Roads would be wrecked by carts and cannons, chickens would be stolen, and that’s before the fighting started. The best armies would pay for the damage they caused and the goods they took with good gold or silver, but that wasn’t as common as the local inhabitants would have liked. Whether you’re getting supplies from the locals or not, it’s still a problem even today.
So there’s a quick overview of what it takes to keep an artillery battery in action for a day. The quantity of stores required every day is not impossible to handle – it’s only a few trucks worth, after all. But organising how to get it from the supply heads to where it’s needed is not easy, and keeping the battery operational and mobile is a significant organisational challenge. It is also very expensive in terms of equipment and training, to say nothing of the people and animals involved. But even so, it’s a lot cheaper than not having the organisation in place when you need it.
Question of the post: What helps make military activity in a story believable for you? And what important aspects often get overlooked?