PACING AND TIMING
In the third part of our navigation basics series, backpacker Alex Roddie and Plas y Brenin instructor Dave Evans explain how to use pacing and timing
IN OUR previous guides we saw how to interpret a map and take a compass bearing. When used in combination with ticking off terrain features as you pass them, these techniques will help you find your way in the hills, but there’s a missing piece of the puzzle: distance estimation.
You will often need to walk on a bearing for a specific distance, then take a new bearing and walk on a new course. This isn’t hard if visibility is good and you’re linking obvious terrain features; but what about featureless moorland – or even the dreaded whiteout? Without the ability to estimate distance, you’re flying blind.
There are two main ways to estimate distance: pacing and timing. “Distance estimation using your feet or your watch is more relevant in bigger, more open terrain,” Dave says. “For example, high moorland or plateau, such as the Cairngorms.”
Pacing
The key to pacing is to know how many double paces it takes you to walk 100m – in a variety of weather conditions and over varying terrain. Count your paces while walking and you can estimate when you’ve covered 100m, and by extension your full navigation leg (don’t try to count a full kilometre). Most people average between 60 and 70 double paces per 100m, but you will need to measure your own paces on a variety of the terrain you are likely to encounter. From flat paths to steep, tussocky heather to deep snow, there will be a lot of variation. Everyone’s different and with experience you’ll become more accurate. “Always start on either your left or right foot,” Dave says. “Be consistent!”
To keep track of pace count, some people use ten beads on their compass cord, and move a bead from one end to the other every 100m. Others keep ten stones in one pocket and transfer them to the other. Use whatever works for you, but stick to a known system.
“On shorter legs and more technical terrain, pacing can be more useful than timing,” Dave says. “But with longer legs and bigger features, pacing can be quite onerous.”
Timing
To time yourself you’ll need a watch. Timing can be useful for longer navigation legs, but it involves more calculation and this can lead to errors when tired. Naismith’s Rule (12 minutes per 1km, and add 1 minute per 10m of ascent) is often cited, but this can be inflexible – and may result in frustration if you’re slower. It’s more important to know your own speed over a range of terrain.
“You should know how fast you walk on a flat footpath,” Dave says, “but you should also know how fast you walk on rough terrain, at night, when it’s chucking it down, in snow – which is a lot slower!”
Measure how long it takes you to cover one kilometre of predictable ground, then measure again – come up with an average. Repeat this for a range of more difficult ground. How much time to add per 10m contour depends on the steepness of the ground; it may be 30 seconds or one minute. “You’re constantly making an ongoing assessment,” Dave says. “Timing should work for you, not you for it. Don’t chastise yourself for not keeping up with Naismith or not reaching your target on time – your hillwalking pace is what’s right for you.”
Traditional and digital navigation
Why learn these techniques when we all carry a GPS-enabled phone? “The difficulty with over-reliance on devices is that you’re less likely to learn the basic skills, and then when the device lets you down you’re going to get caught out,” Dave cautions, adding,
“It’s when devices are most likely to fail that you need traditional navigation skills the most – in the cold, wet or dark. But using both traditional and digital techniques together can be very efficient.”
Practise on easy ground and known terrain, building up your skills before heading for harder hills. Your phone can help with this learning process, Dave suggests: “In good weather, go out with a fully charged phone and use a mapping app like ViewRanger to
“Timing should work for you, not you for it. Don’t chastise yourself for not keeping up with Naismith or not reaching your target on time – your hillwalking pace is what’s right for you.”
set yourself target legs between obvious, well-defined features. Practise pacing and timing, and see how closely your estimates match the GPS result. As you get more confident, switch the phone off and trust the map and compass – then head for more complex terrain.”
The most important thing is to be flexible. Dave adds: “You’ll often use a combination of both pacing and timing. Navigation is a toolbox – it’s about understanding where these techniques fit into the range of tools available.”