Navigation Techniques 2.4: Bearings

Updated: May 18


More in this series:


Navigation Techniques Part 1: Setting the Map

Navigation Techniques Part 2: Measuring Distances

Navigation Techniques Part 3: Timing


Below is the answer sheet to the questions in the last part:

Answer Sheet - 2.3pdf

Part 4 of my Navigation Techniques series will look at Bearings and how we can use them to check the direction of handrails, sight distant features and head in the right direction on our routes.


Bearings


Learning to take a bearing is a fundamental stepping stone in navigation. Bearings are used to help us with the following:


  • Checking the direction of a handrail

  • Sighting a feature

  • Point us in the right direction

  • Taking the aspect of a slope

  • Aiming off

  • Boxing

  • Relocation

The last four points will be covered in a later article. The two types of bearing we need to learn before we can use all these techniques are:


  • Sighting a bearing or magnetic bearing (taken from the ground and transferred to the map)

  • Grid bearing (taken from the map and transferred to the ground)


First, we will look at sighting a bearing.

Sighting a bearing


Taking a bearing from the ground is particularly good for checking the direction of a handrail, taking an aspect of slope and to help relocate yourself by transferring the bearing back to the map (more on this in a later article).


In poor visibility, you may get a glimpse of a feature or your checkpoint in the distance during a break in the cloud. Sighting a bearing on that feature is a great way to ensure you stay on track and can help you relocate.


How to sight a bearing:


  • Hold the compass in front of you and point the direction of travel arrow at your intended feature (if it's a spot feature) or along the feature (if it is a linear feature).


  • Hold the compass still whilst still fixed on the feature and rotate the compass housing until the red orienting arrow is underneath the North magnetic arrow.

Common phrases used are 'red in the shed' or 'mouse in the house'
  • A bearing can now be read along the index line.


In the below images I am sighting a bearing off a telegraph pole (#stayhome and all that!)

Notice how the direction of travel arrow is fixed on the pole (image 1)

I then rotate the base plate to align the orienting arrow and the north magnetic needle (image 2).

I can now read the bearing along the index line. In this example it is 226 degrees


It is important to include magnetic variation to get an accurate bearing. If you are transferring this bearing to a map, remember to 'subtract' the Grid Magnetic Variation'.

Grid to Mag, ADD
Mag to Grid, GET RID

In this example, my magnetic bearing is 226 degrees. Assuming the magnetic variation is 1 degree, To transfer this to a map, I would have to subtract 1 degree from 226 to make it 225 degrees

Taking a grid bearing


We can take a grid bearing from a map to allow us to check the direction of handrails and to point us in the right direction. When planning a route, we take grid bearings from one checkpoint to another to give us a rough idea of what direction we should be travelling in. It is not uncommon to then take several more bearings whilst walking this leg to ensure we are travelling in the right direction.


How to take a grid bearing:


To take a grid bearing, first we estimate the bearing from our position to our next checkpoint:


  • North = 0/360 degrees

  • East = 90 degrees

  • South = 180 degrees

  • West = 270 degrees


The reason we do this is to ensure we don't accidentally do a back bearing (more on this in a later article) and so there are no surprises when reading the bearing. For example, if you know you are travelling NE from your checkpoint, you can expect a bearing between 0 and 90 degrees. If our bearing is outside of this parameter, we can expect an error in our measurement.


We can now use a line on the compass or the edge of the compass to link our position on the map to our next checkpoint, ensuring the direction of travel arrow is pointing towards your next checkpoint on the map.


Keeping the compass fixed on the map, rotate the compass housing so the orienting arrows are parallel to the Easting grid lines (North - South lines) and the orienting arrow is pointing grid north.


Remove the compass from the map. Hold the compass flat in-front of you with the direction of travel arrow facing away from you. Rotate your body until both the orienting arrow and the north magnetic arrow align (as with sighting a bearing a bearing).


Once the arrows are aligned, the direction of travel arrow is now pointing you in... your direction of travel!

You can now read the bearing from the index line and note this down in case you either forget or you accidentally move the compass housing.


See the example below for further learning:

Checking the direction of handrails


A mentioned above, we can use bearings to check the direction of handrails. We can use both sighting a bearing and a grid bearing.


Sighting


We can sight along a linear feature to help confirm our position along that feature. Sight the bearing along the linear feature and transfer the bearing to the map. By knowing what linear feature you are on, you can move the compass along that feature on the map until the bearing lines up.


Grid bearing


Having planned our route and knowing what footpath we are on, we may come across a track junction with multiple footpaths leading off in several directions. If we are unsure which footpath to take, we can take a grid bearing on the map from our position on the track junction, down the footpath we want on the map. We can then transfer this grid bearing to a magnetic bearing and sight which footpath our bearing points down.


Look at all those footpaths and junctions! Confusing? Checking the direction of handrails here is important to stay on the right track!

Points to consider when taking bearings:


When taking a bearing ensure you do not hold the compass too close to the following:


  • Metal zips on your jacket

  • Metal water bottles

  • Mobile phones, cameras or any electrical device.

  • Magnetic clips used on some water bladders to attach the hose to a rucksack strap

  • Walking poles


Remember: Grid to Mag ADD, Mag to Grid, GET RID. (this is accurate as of 2020, with magnetic north moving East of grid north in the next few years, this saying will soon become inaccurate)

Below is the question sheet to this article. Before you can answer the questions, you will need to download the following resources:

Map for Questions - 2.4pdf

You will need to print this out but ENSURE you print ACTUAL SIZE and not FIT/FILL TO PAGE. Take a look at and check your printer settings before printing and then check the measurements with a ruler (1km = 4cm)

Question Sheet:

Question Sheet - 2.4pdf

To put these skills into practice and to learn more, take a look at my Navigation Course I offer.

All confirmed bookings will receive a 10% discount code to use on Harvey Maps products from their site.


Next Up:


The next article in this series will be Part 2.4.1: Following a Bearing


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