Most of the time a sentry does nothing at all. But sentry duty is one of the most vital tasks that a soldier can perform. As a sentry you are there to warn the unit which you are guarding of the enemy’s actions or approach. The safety of your entire unit is in your hands.
Your unit needs to know as soon as possible that the enemy are approaching, or that they have left a package outside the gate. Whatever the enemy does it is the job of the sentry to make sure the officer in command knows exactly what is happening so he can make the appropriate decision.
Although the purpose is always the same, sentry duty comes in two main flavours defined by the situation and what you are guarding. Basically, you can either be guarding a permanent position such as a building, base or permanent camp or you can be guarding a temporary position – most likely your unit overnight while you are out on patrol. In a sense a sentry is like a checkpoint without the searching because you are denying entry to a secure area. The idea is to let no one pass.
When the men are tired everyone has to pull a stag, Afghanistan 2010. (Photo courtesy Tom Blakey)
There is, or was, a third flavour of sentry duty which I hope you will never come across: where two armies were facing one another along ‘lines’, as in World War I, then clearly each had to post sentries to watch out for the approach of the other. You will not get this in counter-insurgency warfare as insurgents cannot hold a line against an occupying force. If you do ever find yourself in a classical war then I doubt it will happen then either as modern weapons do not leave much room for infantry holding static lines.
The threat to a permanent position is that the enemy knows where you are and they have all the time in the world to try a mortar attack, a truck bomb, a frontal assault or anything else they can think of.
The threat to a patrol which is just bedding down for the night – be it a foot patrol or motorized – is much more ‘off the cuff’. An enemy patrol might stumble across you accidentally, have followed you all day or a local might have guided them in. Whatever the way they find you, you are likely to be facing either a mortar attack – which everyone gets to know about at the same time – or a full-scale assault by a moderately sized force. Of course the idea is that the sentry spots the reconnaissance party before the real show kicks off. This gives you time to make what preparations you can for their reception. The job of the sentry here is essentially early warning.
Guarding a permanent position or building
We will assume you are in an observation position rather than manning a ‘checkpoint’. The difference being that you don’t allow anyone in. There are a whole range of places which may be set up for you to do your sentry duty and they all have good and bad points:
Sangar: Most likely you will find yourself looking out of the observation slit of a ‘Sangar’ sooner or later. A Sangar is a sort of fortified box made of sandbags or concrete which is provided with viewing slits. The word was first used by the British Army during its time in the North West frontier and Afghanistan in the 19th century – funny how things don’t change much. A Sangar’s purpose is to protect the occupants while giving them a good field of view from higher than ground level. A well designed Sangar will allow the occupants to look through the slits without crouching or placing unnecessary strain on their backs. If it is difficult to look out then the average soldier will look out less so if you have anything to do with it, make sure the Sangar has comfortable viewing slits.
Tower: You will certainly get a good view because of the height but towers are often badly designed and vulnerable. They should always have a double skin of protection to defeat the RPG rocket. Be aware that a person entering or leaving may be open to sniper fire. See the anti-RPG diagram earlier in designing a defensive position.
Roving patrols: In some specific cases there is a place for a ‘roving patrol’ – for reasons other than to mess the men around. If you have a camp made up of huts or tents, and visibility is not good into the lanes they make, it can be a good idea to have pairs of men walking around the area on a random beat. This is particularly true if the perimeter is not as secure as it might be.
Crying ‘Wolf’: A sentry must never be afraid to tell his superiors when he thinks something is happening. It is far better to check and be wrong than to let something by and perhaps have your base taken by surprise. Commanders should never place their men in the position of being afraid to call in a false alarm – even by ridicule.
Stags: There is a limit to how long a man can stay alert. A man will stay alert for a much shorter time than this. At a permanent position there should not be a lack of manpower and a ‘Duty Guard’ can be created of sufficient size to allow the guards to spend 2 hours ‘on’ and 4 hours ‘off’. 1 hour ‘on’ is even better. Normally the resting ‘off’ guards form the immediate response unit in case something interesting happens. In any situation an off period needs to be a minimum of 2 hours long to allow the soldier to benefit from a full 90-minute sleep cycle.
Watching the watchers: The Guard Commander or Guard NCO should take care to visit the sentry positions at random times to ensure the sentries are alert and attentive to their duties. My own opinion is that a sleeping sentry should be shot but as this isn’t going to occur certainly some severe punishment should be inflicted.
Control room: If you are very fortunate you may have the benefit of a warm, dry, bug-free control room where you can watch the closed-circuit TV cameras set around the perimeter. I think TV cameras are a great idea as one man can watch many screens, all fitted with night-vision, and a comfortable man is an alert man. There are all sorts of clever technical things to make the sentry’s life easier in this situation too – and for the British soldier tea on tap. You see something and you call the guard commander – then he sends out a party to take action. A friend of mine, ex 2eme Rep, French Foreign Legion Parachute Regiment, guards a property owned by one of the richest families in the world. The house is in a large city and he sits 2 weeks on 2 weeks off in a control room watching TV screens. Pretty boring job but terrific money.
Guard Commander: At a base camp an NCO will normally be in physical command of the guard and he will have access to the Duty Officer or Guard Commander as appropriate. Different armies and different units work in different ways but typically you would expect there to be a Duty Officer on duty in any sizeable base and he would have responsibility for taking care of any administrative events which occur at weekends or nights. The Guard Commander is normally the junior officer with direct responsibility for ensuring that the base is properly guarded. These could be the same officer in some circumstances.
Guarding your patrol overnight
When a small patrol beds down for the night it will often hope to be doing so unobserved. But you can never know for sure. It is an SOP to mount a sentry guard overnight just in case.