Taking a Compass Bearing is an essential navigation skill. A Compass Bearing is the direction of travel from A to B, expressed in degrees. We use degrees rather the traditional cardinal points (North, South, East and West) as its more accurate, especially over longer distances. There are 360 degrees in a circle. North is 0 or 360 degrees, South is 180, West is 90 and East is 270.
compass degrees

Taking a Compass Bearing

There are three steps to take a bearing. This is sometimes referred to as the Silva 1-2-3 method after the Silva brand of compass. In this guide, we’re going to look at the Purple Mountains in Kerry (OSI Map 78).

Step 1 – Position the compass along the line of travel

Identify your two points A (where I am) and B (where I’m going) on the map (hint know your grid references).

Compass Bearing - A to B

Place the compass along the line of travel. You can use either the edge of the compass or the inner black line. Make sure the directional arrow is pointing in the direction of travel

Compass Bearing - Place Compass Along line of travel

Step 2 – Turn the Dial

Turn the dial of the compass so the lines inside the housing are aligned with the vertical grid lines. The red arrow inside the dial is now pointing to the top of the map (Grid North) and the black lines site on top or parallel with the blue lines.

Compass Bearing - line up housing with the lines of the map

The number just below the directional arrow is your bearing. In our example, it’s 52 degrees. You’ll need to adjust for magnetic variation. In our example, we have a variation of 4 degrees making an updated bearing of 56 (we’ll discuss why and how we adjust for this in our next tutorial).

Step 3 – Go!

Once you have you’re bearing, it’s time to get moving. (In the below examples we’re using a bearing of 48 degrees).

Place the compass flat on your hand near your belly button your belly button with the directional arrow pointing away from you (make sure there are no metal objects close to it that might affect the reading).

Compass Bearing

Turn your entire body so the two red arrows are lined up. I’ve always liked the mnemonic “Put Red Fred in His Red Bed”. You are now facing the correct direction. 

Compass Bearing

Pick a point ahead of you and walk to it. Check your bearing again and readjust your direction if needed. Be mindful of your surroundings and don’t walk with your head stuck in your compass. This is how accidents happen.

Do this until you reach point B. You use timing, pacing and feature recognition to know you’ve arrived at point B. We’ll discuss these skills and others soon.

Further Reading

Here are some other links to check out

How to use a Map and Compass – Ordnance Survey Ireland

The Compass & Taking a Bearing – Mountaineering Ireland/Star Outdoors

Silva 1-2-3 System – Silva

 

For more guides on map and compass skills, check out the rest of our Navigation 101 series. Let us know in the comments if we missed anything.


2 Comments

Chris · March 3, 2018 at 12:49 pm

Hi, love these Navigation posts ….
When you said “You’ll need to adjust for magnetic variation. In our example, we have a variation of -4 degrees ” I thought it was ” From map to mag = add From mag to map = subtract..? Would this make your reading 56 degrees? Just started out sorry if I’m missing something

    Has Map Will Travel · March 3, 2018 at 7:11 pm

    Hi Chris, glad you’re loving the posts. Thanks for pointing this out. Got a bit muddled in a rewrite. I’ve tidied it up so it (hopefully) makes a bit more sense. I’ll explain magnetic variation a bit more in next week’s post

Leave a Reply

Your email address will not be published. Required fields are marked *