Saturday 7 October 2017

Map, compass,......................and GPS.

Navigation.

Unless we stick to races which follow lines of flags or equally well-marked trails we all have to do some at times. It may be just deciding which track to take at a junction in good visibilty, or it could be finding your way across a trackless, featureless plateau on a dark and misty night, but it's all navigation. And we are all more or less comfortable with the deal, ranging from "I'd much rather follow someone who seems to know what they're doing" to "I'm happy with my own abilities under all circumstances". To help us find our way we have a range of tools which we may or may not have the desire, or the ability, to use.

I last posted about this around three years ago but it's a subject that I think is always interesting to return to from time to time, and in particular the "map versus gps" debate which raises its head on Facebook groups with some regularity.  Two positions that I don't really understand are (a) "the only way to navigate properly is using a map and compass, anything else is cheating", and (b) "I'll carry a gps as a backup to using my map and compass (or vice-versa), but I will normally stick with my preferred method". Let me try to convince you that the game is more complicated (and much rewarding) than this.

So let's have a look at how we navigate, what tools are available and how to choose and use them. What qualifications do I have for addressing this? Well, none at all really, except that I first set a map to a compass over fifty years ago and have been finding my way around hillwalking, mountaineering, ski-touring and running outings fairly regularly ever since. I get lost from time to time (and we'll come to what "getting lost" means later), but anyone that tells you they don't is being a bit economical; the key then is getting back on track, which I don't think I've ever failed to do. Of course, you'll get my view of the world, which certainly isn't the only one, and if all I do here is to make you think a bit more about yours, then the exercise will have been worthwhile. The debate is part of the fun. So here goes:

Maps

If you don't have regular flags to follow, then the first thing you need is a map. Actually, even with flags you might need something else. On the Alpine events such as the UTMB, TDG and so on which always follow paths, flags will always keep you on track, but where the event crosses trackless ground at times such as in the Skyrunning races, it's possible for mist to obscure one flag from the next, leaving you with a bit of work to do if there's no path on the ground. So if ever you read or hear when entering an event that "the course is fully marked", it's a wise move to take this with a pinch of salt and at least have an overall idea of where it goes. But I digress, back to maps.

We're spoilt in the UK; the maps available to us are pretty well as good as they come.  The OS 1:25,000 series are detailed enough to get you anywhere, and have been available (originally in the "2,5 inches to the Mile" form) for as long as I can remember. The other option for the runner is the Harvey's 1:40,000 series. They don't cover the whole country but do take in a lot of interesting areas such as the Lakes and most of the long distance trails; they're waterproof and you don't need as much paperwork to cover the ground. Many events produce a bespoke map in this style, Lakeland 50/100, Dragon's Back, the "10 peaks" races and so on. The only real disadvantages are that you don't get as many contour lines and you don't get low-level field boundaries.

I'm assuming here that anyone reading this can read a map, that is to understand what is meant by the various lines and symbols  -  if you can't, just pick one up and look at the key in the corner! But for a map to be any use on the ground you need to have two other bits of information  -  (1) where are you NOW? and (2) in what orientation should you hold the map to represent the ground around you? In a landcape with plenty of features, you can orient the map from the ground just by turning it to represent what you see, and you can constantly check where you are as you move by noting landmarks as you pass them - path junctions, corners of woodland, footbridges and so on. Most runners using a map as a prime source will fold it to show just the section they are currently traversing, and put their thumb on the landmarks as they pass them  -  "thumbing the map". In my view, even on ground that you are unfamiliar with, this is the fastest way to navigate ground with plenty of features in clear weather in daylight (for example most of the national trails, the Lakeland 100 course and similar trips) You get the big picture and the detail simultaneously and it is easy to see where to go and to judge progress.

"Thumbing the map" in easy territory in 
daylight (Offas Dyke Race)
























Compass

But what happens when things get a bit less clear, say the mist brings visibility down to a hundred metres or so? Well what happens is you lose the landmarks by which you oriented your map - the church spire, the clump of trees, the stream, the nearby hills, the track zig-zagging up the hillside, so you have much less confidence that it tells you accurately what's in front of you. This is where you set the map to the compass (I'm not going to describe that, you know how to do it). Again, if the ground has reasonable features, most runners won't bother with bearings, they will just hold the compass in the same hand as the map and keep orienting the map as they go to keep the N-S gridlines lined up with the needle  - orienteering compasses have a thumb grip (and often no degree markings) to make this easier.

Now to the next level of difficulty; it's still daylight, still misty, but there is no path on the ground to follow. This might be on an open hillside or moorland, or even in a series of cultivated fields where there is no path, you're just moving from one stile or gate to the next. Here's where the scale and accuracy of the map can help. There is a lot of detail on the 1:25000 OS maps, which means that identifiable features are closer together. In a series of fields with each boundary and the line of the path marked on the map (even if not on the ground), you can often just keep the map oriented in your hand and set off in the direction shown on the map from one landmark (say the corner of a field) with a good chance of finding the next one (say the exit gate) if it's not too far, maybe a couple of hundred yards; you may not hit the gate spot-on but it won't be far away when you reach the field boundary and should be within sight.

But if your map shows less detail (such as the Harveys 1:40,000), or identifiable landmarks are further apart, you may need to be more precise about how you progress from one to the next; you may need to follow a bearing. Again I'll assume that you know how to translate a direction on the map to a bearing on your compass; but it's how you follow the bearing that often gets overlooked. Not many people can follow a bearing accurately by just looking at the compass and moving in the direction that it points; try it on a park or football pitch, you're likely to find that you rapidly veer off to one side or the other like most of us. The normal way to follow a bearing is to select something in the far range of your vision that is on the bearing and then go to it; then repeat the process with more of these "bearing markers" until you reach the landmark you set the bearing for. Bearing markers will be rocks, fence posts, trees, anything that doesn't move; the further apart they are, the more accurate your progress will be.

This sounds OK, but what if the ground in front of you is so featureless that there are no features you can use as bearing markers? Well, there are at least three tactics that you may be able to use to get somewhere;-

1. If you are not alone, you can use each other as markers; one person goes ahead on the bearing, directed by one standing still to go left or right to stay on the bearing until at the limit of visibility. You then move to him/her and repeat the process. No good if you are alone though!

2. You can accept that you may not follow your bearing accurately by "aiming off". Suppose your next landmark is a footbridge across a stream. Your concern is that you will miss it, so you set a bearing to miss it deliberately, say by aiming to the left of it by a hundred hards or so (how far you aim off depends on how far away it is), When you eventually hit the stream you now know that you have to turn right and follow it to reach the bridge.

3. You may not have features in the precisely the direction you want to take, but you may be able to use other reliable features as "handrails". In the example I gave above, instead of aiming off you may find that a wall or fence leads from where you are to meet the stream say a quarter of a mile from the bridge. You can then follow the fence then the stream as reliable handrails; you will travel further but you will know where you and get to where you want to go without problems.

All this so far is pretty standard stuff and anyone who has spent any time wandering around the hills will have probably used most if not all of these techniques. It's not rocket science and easily learned and practised. But what you notice is that as conditions get progressively unhelpful, then navigation gets a bit more time consuming, both in thinking time and often in travel time too.  But then there are a couple more factors that influence ultra running events in particular.

Darkness

Now you may be different but when I've gone out for a day in the hills I've normally tried to confine my activity to the daylight hours, which makes the whole thing not only easier but a lot more fun. Ok, I might have walked up a few glaciers in the dark on "Alpine starts", and had my share of benightments, but these were normally minor parts of the trip and a bit of faffing around navigating carefully didn't compromise the day too much.  But once you get into the ultra game, unless you confine yourself to shorter events in the summer, then progress in the dark is very much part of the deal. It might be only two or three hours at the end of an event because you don't travel as fast as the leaders, or maybe 16 hours out of every 24 on the Spine, but either way how you navigate in the dark will have a significant impact on your race.

In the dark, everything gets more difficult. Running itself is more difficult for a start. In daylight, even in quite thick mist, you're getting signals via your peripheral vision on the near distance of the way ahead, allowing you to concentrate on where you put your feet while adjusting your direction of travel at the same time. In the dark you have no peripheral vision so must concentrate on one thing at a time.

Navigation, as we've covered up to here, is still completely possible with your map and compass, but again because you get limited feedback from the ground, only what you can see in your torch beam, then everything gets slower. Which leads to the other factor:

Speed

Ultra events are races. Now you may not actually be competing to win, but how fast you cover the ground will always be important to you. And as we have seen, the impact as navigation gets more difficult, through featureless ground, poor visibility and darkness, is that you move slower. How fast you navigate might be the difference between meeting the race cut-offs and missing them.

So here's where we start to get to the real debate. Do we have any more tools nowadays that will help us counteract this reduction in speed? And of course the answer is yes.

Reliability of electrical/electronic devices

Let's get this one out in the open before we start.  A frequent criticism I hear of the use of electronic navigational aids is "What happens when they go wrong?" Well I have two answers to that:

1. I have been using electronic aids to navigation, in the form of watches (in their non-gps form), altimeters, hand-held gps units and more recently the gps-enabled watches, for around forty years now. I have never had one fail, other than when I forgot to charge it or put batteries in.

2. I would never advocate the use of electronics as an outright alternative to a map and compass and the ability to use them, so whatever happens you will always have a way to navigate.

So what I'm much more interested in is what can the electronics do for us that is better than a map and compass.

Altimeter

Long before the advent of gps we were using altimeters. Knowing the elevation you are at gives you a real step up in information to work with. It helps pinpoint your current location, gives you good feedback on where you are on a long climb for example, and also allows you to "handrail" a contour when no permanent features are available. This latter technique was the one that got you up crevassed glaciers in the mist in relative safety. On the Tor De Geants, an altimeter is on the mandatory equipment list (or was when I did the event five years ago) and proved much more useful than anything else in giving you feedback on how far up a particular climb you were ("Just how much longer is this going to go on upwards?") On all modern gps watches you get an altimeter as part of the deal, so it's really worth learning how to use it and when it can help you. But the real development in electronic navigation came with the advent of the hand-held gps.

Hand-held gps

These were a bit of a waste of time until the end of the cold war, not having more than about a hundred metre accuracy until the signals from the military satellites on which they depend were unscrambled for civilian use; nowadays, if you stand still for a minute they will pinpoint your position to within a metre or two, giving you immediate access to the fundamental rule of all navigation, that is knowing where you are NOW.

There are lots of models out there, the one you choose will depend on your individual priorities. They all have the facility to load a predetermined route and then to show you where you are in relation to it  -  you can in effect just "follow the line". All but the most basic models will allow you to load maps as a background to the line, so you can see where you are in relation to the world around you as well as in relation to your route. Larger models allow you to have a bigger screen so can see more of the map, but are bulkier and heavier to carry. Touch-screen models are faster to operate but I personally would only use a button-operated type  -  slower and clunkier but unaffected by weather and can be operated wearing fairly thick gloves.

However, just like a map or a compass, a gps is of limited use unless you take the time to understand what it can do and how to get the most out of it, and then practice as much as you would with a map.  Buying a gps to put in your pack as a "back-up" should navigating with a map get too challenging is for me a pretty questionable exercise. Without practice, you may find it no better than (or even worse than) a map.

In good visibility on almost any ground, a competent map navigator will be faster than a gps user  -  he is getting more information simultaneously and can translate that into action immediately. But when conditions begin to cut off some of the information available, a gps will start to become faster. Taking bearings, using bearing markers, aiming off, using handrails, all of this fairly time consuming stuff becomes unnecessary, you just follow the line on the screen. The flip side is that in doing this you become (if only psychologically) more detached from where you are on the ground. I use a Garmin ETrex30 unit, which when set to the scale that I feel is most efficient for following a route, shows less than one square kilometer of map on the screen. Great for negotiating the next two hundred metres but you get no idea of the big picture, what the next mile or two of ground is likely to be like, any obstacles, climbs, etc coming up, how far to go to the next checkpoint, and so on.


Route screen on my Etrex30 gps - easy to follow but a limited 
view of the world
























A great combination in poor conditions, especially at night, is to have a companion so that one of you can work the gps and the other the map. By feeding each other information you can make rapid progress and understand the big picture at the same time, almost as well as in clear conditions.

I think it's worth a word here about how you put routes into a device. I often see comments or questions such as "can I get a gps file for route (X)". Technology is so simple and easy these days, you can just see a file somewhere and with a couple of clicks it's in your machine. I personally never do this. I like to see the file on a map first, then I recreate it using the waypoints that I choose rather than the ones that the originator has chosen. This is because the originator's aim is to describe the route, whereas I want to follow it, and these are different objectives. I may want to put waypoints at all the key direction changes, and ignore a lot of the others for example. Plus, I find that by actually manipulating the route manually a lot of it stays in my brain before the event much more easily than if I just imported it without thinking.

GPS Watch

But why would you bother with a hand-held gps, when you can follow a route just by using your watch? Well, for me, a few reasons:

1. On a watch you only get a route line, no map possibilities, so although you can still follow it there is nothing to tell you where you are on the ground at any point.

2. Gps watches always run from rechargeable batteries, and the gps function is a relatively high power use, so charge has to be managed carefully even on shorter ultra events. On a hand-held you simply put in another set of batteries and are good for another couple of days.

3. Most runners keep an eye on elapsed time and distance, maybe even other parameters such as pace, quite regularly, and if using the watch for navigation as well this means frequent switching of functions which can become a bit of a pain over an extended time period.

But this doesn't mean I get no navigational input from a watch. One task that I find it very useful for is providing a fast spot check on current location. This can be useful for, eg; 

1. Settling those "well I think we're about here" sort of conversations (maybe with yourself)

2. Getting a quick progress report. Say you're going along a long, easy to navigate track but in misty or dark conditions (Lairig Mhor, Cam Road, Old Coach Road sort of territory) there aren't that many features to tell you what progress you're making so getting your location can answer the "how much more of this do we still have to do?" question. It's just another way of getting the bigger picture.

These are just examples; there are plenty of other occasions when a ten second exercise on the watch to give you your precise location can give either useful information or a confidence boost - worth the time I think.

Getting Lost.

We all get lost on occasions -  by which I mean either (a) you don't know where you are, or (b) you think you know where you are, but are mistaken.  In my experience this normally happens not because you don't have the ability to navigate that particular ground but because you lose concentration and take your eye off the ball. You may be chatting to another runner, going along a series of tracks that don't seem to need any detailed navigation, following other people because it was pretty easy so far and you didn't feel the need to find your own way  -  then suddenly it dawns on you that you've broken the first rule  -  you don't know where you are NOW.  I find this can often be exascerbated by not having all the tools to hand  -  map, compass, gps etc maybe still in sack.  You're then tempted, rather than stop and get sorted out, to push on in the hope that you will see someone else or get an indication on the ground that convices you that you're still on track. That way lies a lot of time wasted.

I've tried to instil some personal discipline by making sure that on any event that I don't know pretty well from start to finish, I have all the tools to hand; map, compass, gps, all in separate pockets of lightweight frontpack which took a couple of hours to make and clips with two mini carabiners onto the straps of any pack I happen to be wearing (shown in the photo earlier in this post). With stuff handy it's easy to keep an eye on where you are on the map. And if all else fails I still have two devices that can tell me precisely where I am now (hand-held and watch), and I use them sooner rather than later. I always switch the hand-held on to follow the route, even if I don't intend using it much if at all - a set of batteries will last a day or two and it seems a small price to pay to get information quickly when you need it. Similarly with my watch; on a long event I won't bother with the "running" mode, I just switch it to a "walk" mode so it still gives basic feedback on time and distance but the battery will last a couple of days so if I need it for a quick position, it's available.

Now this doesn't mean that you can't get back on track without using the electronic devices; if you've learned your stuff well you will do it  - but it will take longer. Which leads us nicely to the end game; what am I really saying after all this ramble?

Efficient navigation

I'll recap what I said earlier here; these I my views, you don't have to agree with them but I've developed them over a fairly lengthy period and they seem to work for me. So my philosophy is as follows:

1. Of course I want to navigate accurately, but I also want to navigate efficiently so that I don't waste time either on the navigation or by covering unnecessary distance.

2. I have numerous tools to help me navigate, and it seems foolish not to use them all.

3. I have discovered that for me, in daylight and with good visibility, I move faster using a map, or a map and compass combined.

4. I know that in poor visibility or at night, unless the ground has regular easily-identifiable features, I move faster using a hand-held gps. I will normally refer to the map regularly for the bigger picture.

5. If I am in any doubt at all about where I am in any conditions, I will immediately get a grid reference from my watch.

6. This means that any new piece of navigation kit that I get, I have to take the time needed to learn to use it effectively, and to practice with it so I know exactly what it will and won't do.

Happy navigating!

..........................................................................

Well, all that sounds ok. But I've been in the Lakes for a week or so just pottering around on routes that I know well  - the only navigation equipment I've taken with me is my brain. This afternoon I just started to look out my kit for the "Lakes in a Day" event which starts first thing tomorrow morning.............and realised I'd left my compass back in Chester.  A quick sprint down to Blacks for a replacement. You may re-assess my competence if you wish.........