SAS Ultimate Guide to Combat

For sure a heavier type of weapon such as a cannon shell or a machine gun of greater than rifle calibre will make short work of a wall whatever you do to reinforce it. The best thing is to dig holes for shelter and fire positions and use the building for cooking.

Towers

Some permanent bases have towers already built so presumably they were built properly. With a tower you get a great view of the enemy from a comfortable, dry position and should be able to fire onto anyone creeping towards your position. This is a blessing. Less good is the ability of an RPG or .50cal machine gun to punch holes in anything but the stoutest tower.

Concrete watch towers with wire surround to prevent RPG7 damage by detonating them too early. I would prefer that wire to extend above the top of the tower. Camp Bastion, Afghanistan, September 2010. (Corbis)

DEFENSIVE POSITIONS: SELECTION AND LAYOUT

As every defensive position is different owing to the ground, weapons available, defending strength and so on, I am going to show you what to look for in selecting a defensive position and how to lay out the perfect defence. You can then mix and match the principles to cover the less-than-perfect circumstances in which you will doubtless find yourself.

At the root of the layout issue are the two conflicting requirements of a defensive position: these are to be spread out as much as possible against mortars or artillery and to be as small as possible so your forces and weapons are spread around as short a perimeter as possible. It doesn’t take an ‘Einstein’ to see that the shorter the perimeter you are defending the closer your guns are together and therefore there more concentrated the fire which an attacking force has to endure.

First of all here is a list of natural features you want to take into account when selecting your stronghold:

  Height: Wherever possible set up a defence on a hill. The reason for this is that if you overlook the surrounding area you can see the enemy advancing and you can see your fall of shot to correct for accuracy. Of course, avoiding having the enemy overlooking you also stops him correcting his own fall of shot. This is not a new idea.

And it is also much harder work skirmishing to the attack up a hill. Not surprisingly this is why castles are mostly on hills. Being on a hill or at least raised ground also lessens the chances of being flooded by a downpour. Not fatal but unpleasant enough.

  Trees: Avoid tree cover when you can, even when this means giving up the shade, because mortars and artillery falling onto trees become air burst. See Not Getting Shelled – High Explosive. Trees and bushes around your base should be removed as they let the enemy get close before you see them.

  Ground: Pick ground you can dig a hole in if possible. Digging into baked or rocky ground can not only be demoralizing but it can encourage soldiers to ‘forget’ to dig in properly. Avoid land which may get flooded if you can.

  Insects: Some places have the most annoying insects like wasps, ants and various types of ticks. So far as you can, check out your site for these before settling in.

  Access: With a larger base you are going to want ready access for vehicles to re-supply if possible. If there is only one road you may find it mined and ambushed so often it is unusable. It is always best to have a range of possible exit points so as to allow you to get patrols out and back in without the enemy knowing where they can catch you. Consider also the possible need for re-supply by fixed-wing aircraft, helicopters and boats.

You may also want a route out of the base which is sheltered from fire to escape if this becomes necessary. Weigh this against the possibility of offering cover to approaching enemy forces.

Spreading the risk

We have already seen that the shorter your perimeter the more concentrated your fire can be at all points along it.

What is not quite so obvious is the advantage of spreading your forces over an area. Someone shelling the position in the example to the right with mortar fire from a safe – for them – distance away has a beaten zone – the area where his bombs are going to fall – of roughly 300ft x 300ft = 90,000 square feet. A bomb would actually have to land in your trench to do you harm and your trench is 6ft by 2ft = 12 square feet.

So the maths say there is only 1 chance in 7,500 of any individual bomb landing in your trench. That is better odds than the guy firing the mortar has. It’s better odds than crossing the highway safely in some towns.

Killing ground

All around your position you want a clear area of as large as possible. 100 yards minimum by choice. 300 yards is better. The two reasons for this are:

  To stop the enemy shooting at you from close-up cover

  To make the enemy run across a lot of open ground in his final assault to contact

If there have to be any ditches or hollows in the killing ground which you cannot see into, and which therefore may give cover to an attacker, fill them with mines and razor wire. Zero-in mortars, artillery and fixed-line machine-gun fire if you are a larger unit.

Laying out the position

Once the site of the position is selected one person should be authorized to mark out all the defensive fire positions. A circle gives the shortest perimeter for the greatest area covered. Normally two men to a foxhole is good as single foxholes can get lonely. Also, if one man is killed its whole arc of fire is not left undefended.

Arcs of fire are allocated to each position and these arcs should not only interlock but should still interlock when one position is taken out of the scheme.

An ‘arc of fire’ is the angle of responsibility given to any man or group to cover and defend. In the diagram below it can be seen that not only is the position unapproachable without coming under fire but it will remain so even if any of the foxholes are silenced.

Machine guns should be sited at points of particular danger – such as where the enemy can get closest to the position without being seen or fired upon. Snipers should be positioned where they can see the furthest or are otherwise of most use.

As I said earlier, if you are going to be staying in a position for some time it can be a good idea to dig communicating trenches between the fire positions so as to allow reinforcements to be moved around without exposure to fire. With a larger unit you might want to consider building a command post and centralizing food, water and ammunition supplies. There might also be room to establish a first-aid post – medics are always good for morale.

Wire

Military barbed-wire is like the stuff farmers use but the spines are longer and closer together. Razor-wire is a central strand like barb-wire but with blades like old fashioned razor-blades in place of the spines. If you are in a hurry to cross a wired-up defence you can tolerate rolling over barbed wire but razor wire is much less fun. Both types come in coils which are opened out into loose spirals when in position.

Wire doesn’t stop soldiers it merely slows them down so you have more time to shoot them. Attackers tend to get caught up in wire and have to disentangle themselves. It is best set loosely in coils and tangles because this way it is harder to clear a path through it and, when entangled, harder to get free. Wire should always be covered by fire. Preferably machine-gun fire. And a few mines are no bad thing either. There is no point slowing down his advance if the enemy can safely take his time.