Navigation for Fellrunners Part 2
First of all thanks for all the comments from the first section of Basic Navigation; they were much appreciated. I hope that those of you I replied to directly found the information useful.
In the last 3 months you should have been out practicing your basic techniques; setting your map, memorising your 5 D’s and ticking off features as you go. The best way to improve any skill is regular practise and so much the better if it gives you the excuse to run over new hills or unfamiliar terrain.
We will now take it up a step and add some finer details and tips
First of all, let’s come back to contours. Once you’ve mastered reading contours a wealth of information can leap from the map such as angle of slope, direction and the shape of the ground.
Spotting the difference between concave and convex slopes. This is particularly important in the higher hills and where there is poor visibility. A concave slope starts steep but shallows off, with the whole slope visible beneath. A convex slope gets steeper and can hide nasty surprises, particularly where the ground is rocky.
The more you study the map the more you can spot even the tiniest of detail
A – Narrow Ridge line ascending North East-note the sharp angle in the contour line
B – Blunt rounded hill side descending North
C – Stream gently descending to the North East
D – Stream descending a steeper concave slope Easterly
E – A flat area on a spur
F – A broken contour shows a significant rise that does cross through the next full contour (not on OS maps but may show a spot height)
The angle of slope can be worked out from the number of contour lines per cm. For example, a 1:25,000 map has one cm to 250m. The contour interval in mountain and moorland areas is usually 10m with thicker index contours at 50m intervals (every fifth contour). Five index contours over one cm on the map give a 45° slope.
Some compasses come with a clinometer which can measure a slope for you. Check the pacing chart below for more on slope angles.
The more you study the map the more you can spot even the tiniest of detail (see detailed interpretation of a section from a Harvey map above ).
In the last edition we looked at the basics of how to take a bearing. We will now look at using the bearing with more accuracy.
Walking or running on a bearing can be quite an art. After taking your bearing, don’t immediately start moving – think first. Am I heading for a big ‘catching’ feature like a river or wall line and aiming off? If so away you go. If you need to be more precise, look at your compass and aim for a point you can see on the line of your bearing. It may be a tree or rock but you can now run to that feature without recourse to your compass. From that feature repeat the process until you get to your target. You will find this much more accurate and faster than just starting on the bearing from where you first took it, and it should mean you are much less likely to trip up!
If you think you have wondered off course, a good technique to know is the “Back Bearing”. Simply turn the compass round so the white (south) needle is in the “shed”. The arrow should be pointing at the place you set off. If not move left or right until it does. You are then back on your bearing.
It is worth noting that whilst crossing a hill side or plateau you will take a line of least resistance, often resulting in you slipping down the hill or being blown down wind. By using features you will avoid this and it will allow you to find the best ground for moving over before returning to the bearing.
The dark or thick fog can limit the distance you can pick out an object at. In these conditions it’s sometime worth pairing up and using a technique called leap frogging. One person goes out in front to the limit of sight and communication. They become the feature until the second person catches up. The first person then leapfrogs in front again. If you wander off line your partner can signal to go left or right until you are back on track. It’s not fast but it is accurate. In an emergency in the dark you can always leave a spare torch or light stick on a high point to use as back bearing, returning in daylight to pick it up.
Sighting a bearing from a feature to confirm your position
If we need to find where we are whilst traveling along a known path, ridgeline, stream for example, and we can see a known feature such as a trig, church, crag we can take a bearing from it. First point the compass at the feature then rotate the bezel until the red north needle is in the shed. It’s always worth repeating this a few times to make sure you have this as precise as possible.
Now, the feature can be miles away so we need to allow for magnetic variation. This is the difference between where your compass points (magnetic north) and the north on the map (grid north). This information is found on your map legend. At present on the OS OL 4 NW Lakes, the variation stated on the map for this year (July 13) is 1.55°W (just under 2 degrees west or one mark on a good compass). Incidentally, this is decreasing annually and actually speeding up so within 5 years we’ll be down to less than 1 degree. The further away our known feature is the more important this is.
If we say the bearing is 304° on the compass (magnetic north), we will convert it to the map (grid north) by subtracting 2° to give us 302° on the map.
A way to remember this is “Mag to Grid – Get Rid”.
Place the compass on the map making sure that the northing lines on the compass match the northing lines on the map. You can now slide the compass until one edge is on your known feature. If we now draw a line along the edge the point where the line crosses our path is our location.
We don’t use magnetic variation any more when walking on a bearing as the difference is negligible over shorter distances.
Measuring Distance and Duration
There will come a time when you will need to know exactly how far you need to travel along a path, stream or ridgeline in the mist or dark or when there are few, if any, features to tick off. The two techniques used for this are pacing and timing. Both are very accurate after some practise. I tend to use pacing under a 1000m but move to timing above this distance – counting out 3000m metres can be somewhat tedious to put it mildly!
In pacing you count just every second step. For me, on the flat 30 double paces is 50m. This changes dependant on angle and terrain so the best way is to measure your own paces against a fixed distance. If you or a friend has a 50m rope, go out and lay it over various terrain, count your paces and make a note. You will soon work out how many you take. It is important to note that you need to take a “normal pace” and not an exaggerated one. One way to make the counting easier is to fasten 5 button toggles to the lanyard on your compass or rucsack and slide one along every 100m, once you have moved them all you have done 500m and you can continue the count by moving them back. .
For timing, I use a variant of Naismith’s Rule. This is designed for walking so you need to check your times over a set distance if you are running. Again, measure it out on the flat first then do the same distance on a climb and note the difference. A Bob Graham pace will obviously be different to a two hour score event, so practise and take a note book or download the blank pace file below. Once you have this information you can make an algorithm which is very accurate. Make a small card and have it attached to a compass or rucsac ready to be used. Below is the version with instructions I hand out on my navigation course as a guide. You need to work it out for your own stride length and pace however feel free to scan/laminate it until you can make your own.
I’ve attached a blank for you to fill with your own pacings – click here
Primary and Secondary features
We’ve already talked about ticking features, another phrase often used is ‘telling the story’.
Imagine again how you would direct someone new to the area to get to a shop 5 miles away; just repeat this with a map using your 5 D’s. Now imagine you haven’t been in that area for a while and try again. It’s possible things have changed and the same is true for the hills; walls can be moved, paths redirected, woods cut down, so always navigate by primary natural features first such as rivers, crags, valleys. Only then use secondary manmade structures like walls, fences, houses, plantations or even paths. Remember man made means it can be man removed. Cairns are a good example as they do not tell us anything except where they are mentioned on a map. They are easily made and easily moved.
How to make a route choice
Whether to take a direct route or contour round is always a tough choice. By using your pace notes however, you can make the choice easier.
First work out the extra distance run by contouring round. This can be quickly done by first drawing the straight line route then drawing a perpendicular line out to the furthest point on the contour line. This line is approximately the extra distance run. Next follow the straight line route and count the contours to work out how much extra climbing there is, for example you may find you have to run 2kms further but there is an extra 300ms of climbing.
If you know can run at 6kmh and climb at 30 seconds per 10 m that gives you approximately either 20 minutes of running or 15 minutes of climbing….so the direct is quicker. Unfortunately it’s not quite that simple. There are often other deciding factors which can only be made on site and with experience. The contour path may be a smooth grassy path whereas the direct rough and tussocky for example. You will also have to consider how difficult the navigation will be; is there a good catching feature at the end to help you locate your check point? In a mountain marathon you may wish to save your climbing legs for later in the race, saving 5 minutes at the start by losing 15 later is not a good plan. Another factor for consideration is the environment. Will you need water to drink? Is the wind strong in which case the more sheltered route may be better. When the clag is down I always favour the easiest to navigate – it might not be the fastest but if you go wrong it could cost you even more time.
I’ll briefly mention altimeters as many sports watches have this facility. They do offer a third dimension to navigation as long as you are careful. Altimeters work on barometric pressure so need regular calibrating. Even during the course of a long race they can lose accuracy. My tip is to ignore the actual height shown and concentrate on the differential. For example, if you need to climb a stream for a height of 130meters, zero your altimeter regardless of where you are and climb until you reach 130m. If you wish to keep the height real then please remember to check it regularly against known spot heights, particularly in unsettled weather
Navigating on the run
The more proficient you get at navigating, the faster you will want to move. This introduces the new problem of trying to be accurate whilst running. The answer to the problem is a traffic light system.
For example, from your known location you know you will run north east for two kilometres until you pick up a stream. You then need to turn left and follow upstream it until you reach a stream junction. This is easy navigation so go fast (Green Mode) only checking the compass briefly to confirm we are going the right way. It’s also possible that during the green phase we can be planning ahead so when we reach our destination we do not have to plan our next leg.
From the stream junction you then need to head 380m up the right branch looking for a sheep fold. We need to be a bit more aware of distance and direction now so will concentrate more (Amber Mode).
Let’s say, from the sheep fold you need to pace a distance on a bearing to a prominent stone. Here full concentration is required (Red Mode). This method allows us to move fast when the navigation is easy and slow down when we need to take care. The other benefit of this is you can leave a checkpoint quickly thereby not guiding in other runners.
Relocation – Or what to do when lost
Let’s be totally honest here, everyone gets lost at some time.
The main reasons for getting lost is nearly always complacency or not paying attention; leaving map and compass in your pocket or rucsac and not following the route. How you recover will depend on how you navigated. First of all stay calm and think it through. Go over your 5 D’s. Look back over your route. How far have you travelled? In what direction? How long since you last looked at the map? What have you seen? From this alone and using your pace/time chart you should be able to narrow your location down a probable area. Now, consider if you can see any obvious features that will be evident on the map? Take a bearing down the fall line of the slope; does it match the probable area as shown on your map? Maybe there is some high ground nearby that would afford a better view? Can you plan a route to a big catching feature? On the Kinder plateau for example, if you get lost you only need to travel 10-15 minutes north or south and you will find yourself on one of the edges and a safe route off.
In good visibility it is possible to relocate using a technique called a Resection.
Find at least 2, preferably 3, obvious identifiable features and sight a bearing on them as described earlier. The bearings should cross at the same point, however, what is more likely is you get a small triangle. Your position will be within the triangle.
Putting it in to practice
Most of our medium and long race routes require navigational ability, even those where the route is fixed. Navigating over the hills requires some skill and simply following someone else is not only risky in terms of your final position but can be dangerous should you get split off from the group. How many times do we read that a runner went the wrong way and took 20 runners with him/her. The way to avoid this is do it yourself, with confidence.
Mark up your map with the bearings off the tops or from checkpoints points. Note distances to turns and what you will see on your way there. Some of my maps have secret trods marked on them that I’ve found on reccies
When you mark you map up try and avoid writing on the route itself however as you doing so coule obscure a useful feature. Try not to mark a check point with a dot or a cross, draw an arc around them, leaving the route in the opening (imagine a letter C)
If you have specific questions please get in contact and I’ll do my best to respond promptly.