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After Map Reading, using a compass is the next most important skill in navigation. This series of articles explains the essential techniques for land navigation with a compass, from the basics of setting the map to advanced relocation techniques in poor visibility.

If you are unsure which compass to buy or confused about any of the features on your compass, please see our accompanying article on choosing the right compass for you, which explains the features of the compass in detail. A compass is not something you should economise on, a cheap compass will almost certainly let you down.




This second article builds on and incorporates the skills covered in part 1 and introduces the following intermediate compass skills: Taking a Bearing, Walking on a Bearing, Back Bearings, Aiming Off and Attack Points.

When to Take a Bearing


A common misconception about compass bearings is that once you’re following one you’ve ascended to a higher level of navigational accuracy. This is not necessarily the case. One of the basic principles of land navigation is handrailing: identifying a linear feature which you can use as a ‘handrail’ across the terrain. At its most basic this could be a footpath, boundary, or water course, whereas an advanced navigator might identify a subtle change in the gradient as a handrail. Neither navigator need use their compass except to confirm direction of travel.

  • Choosing to rely solely on a compass bearing introduces several possible inaccuracies:
  • Interference affecting the compass from magnetic, electronic, or metallic sources nearby.
  • Failure to allow for Magnetic Variation.
  • Faulty compass.
  • How accurately you take and read the bearing. This could be due to poor weather, poor visibility, reduced dexterity, or just individual interpretation.
  • Your ability to walk in a straight line. This is not as simple as it sounds! The terrain may not allow it. Human beings tend to drift downhill; some have a dominant cerebral hemisphere, most don’t have a matching pair of legs.

Most of the above can be mitigated with good sense and the techniques covered below, but following a physical handrail is easier, faster, and more reliable than trying to hold a straight line across challenging terrain with just a compass bearing for reference. Drift just 5 degrees from a bearing on a leg of 500 metres and you will miss your destination by up to 50 metres. In short, walking on a compass bearing should be reserved for terrain without clear handrails.

Taking a Bearing


We learned in our previous article that the compass has 3 functions: to provide a constant (Magnetic North); as a protractor for calculating angles relative to Magnetic North and to accurately measure distances on the map. Taking a bearing has 3 easy steps. In steps 1 and 2 we use the compass as a protractor, only in step 3 does the needle come in to play.

Step 1: Place your compass on the map and use either the edge of the baseplate or the printed line on the baseplate to make a straight line between your current position and your destination. Make sure that the Direction of Travel arrow points towards your destination.


 

Step 2: Hold the compass in place and turn the compass bezel until the red arrow in the housing aligns with North on the map. You have now taken the bearing. Read your bearing on the bezel at the point where the Direction of Travel arrow intersects. It’s at this point that you should adjust for Magnetic Variation.



Step 3: Lift the compass from the map and hold it flat in your hand. Turn around until the red end of the needle aligns with the red arrow in the housing, ‘put red to bed’. Your Direction of Travel Arrow now points towards your destination.



Walking on a Bearing

The next step is to ‘Sight’ – look in the direction your Direction of Travel Arrow is pointing and pick a distinctive feature to head for. Be flexible with what you choose to Sight on; visibility, gradient and ground cover vary. On a clear day, over a short distance, you might choose a feature on the horizon, or you may even be able to see your destination. If your destination is out of sight, then select a distinctive intermediate feature. When the mist is down, or after dark, you might sight on a patch of heather just a few steps away. Once you are ready to move, put down your compass and walk to your chosen feature – do not try to Sight and walk at the same time, your compass must be still and steady to be accurate. Once you reach your feature, stop and Sight again before continuing. Repeat until you reach your destination.

Strategies

Having considered the potential pitfalls of using compass bearings, let us now consider strategies to help minimise the risk of going awry:

Using a Back Bearing

Initially you will have clear line of sight back to your start point, you can take advantage of this by using a Back Bearing. 
Stop walking, then with your compass flat in your hand, turn around until the white (South) end of the needle aligns with the red arrow in the housing, “put white to bed”. The Direction of Travel Arrow should now point back to your start point. If it does, you’re holding a good line, put red to bed and continue. If it doesn’t, you’ve drifted off course. To correct, side-step left or right until the Direction of Travel Arrow points at your start point.

Teamwork

Tramping behind a navigator on a stop/start compass leg can be tedious for your companions, more so if you go wrong. Keep them occupied and improve your accuracy by using them to keep you on your bearing. Take your compass bearing as usual, then ask your companions to walk ahead of you while you stand and sight for them. Ask them to stop after an agreed time (50 paces for example) and to turn and look back to you. Sight carefully along your bearing, correct them if necessary, then head towards them. Repeat as necessary until you reach your destination.
Though a little slower, this technique significantly improves accuracy and has the added advantage of allowing you and your companions to negotiate obstacles such as boggy areas while still holding your bearing.

Aiming Off

If your destination is a point on a linear feature, such as a path junction or a meeting of walls, you can improve accuracy by Aiming Off. In the example below, attempting to hit the confluence of streams precisely (via the dotted line) is fraught with potential errors; you are likely to drift left or right, miss the confluence and lose time searching upstream and down. If you instead take a bearing to deliberately miss the confluence, Aim Off, you can hit the stream at a point either side, then handrail along the stream to the confluence. Aiming Off to the uphill side will improve your chances of seeing your destination.




Attack Points

If your destination is close to a larger, easily identifiable waypoint, use this Attack Point to reduce the distance you need to cover on a precise bearing. In the example below, a direct bearing to the destination requires precision and concentration and is again fraught with potential error. Use a rough bearing to get to the lake, handrail East to the Attack Point (the outflow) then use a precise bearing to reach your destination. As with Aiming Off, this technique adds distance to your journey but substantially reduces the potential for error. 




Taking a bearing is a fundamental navigational skill that can be practiced anywhere with a map and compass to hand. Walking on a bearing requires practice and concentration, take the time to become proficient and consider your strategy ahead of every journey. 
In our next article we will cover some advanced compass skills, introducing effective Relocation tactics using Slope Aspect and Transits; Search techniques, and Hazard Avoidance.

The Author

This article was written by Pure Outdoor Staff Member - Stephen


An experienced mountain skills coach, road cycling guide, caver, climber and fell runner, Stephen instructs navigation and mountain skills year round and has led countless mountain challenges and expeditions throughout the UK and Europe. Always cheerful in the face of adversity, and with a taste for the epic, Stephen achieved a long-held ambition by completing the Bob Graham Round in June 2015 - loving every minute of it!


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