# AZIMUTHS AND COMPASS QUADRANT BEARINGS

## (THINKING IN CIRCLES)

 "I see that on our compass rose the azimuthal (gulp) direction 45° is called 'northeast' (NE), and 135° is called 'southeast' (SE), etc. Thank goodness!! 'North', 'south', 'northeast', 'southeast'...that's how I'm used to giving directions! I'm much more comfortable with names than numbers! "

 "There's a reason for the numbers, Lou! 'North', 'south', 'east' and 'west', and 'northeast', 'southeast', and so on are OK as names without numbers! But all the directions in between them are too vague! The names need numbers attached to them. And that's what compass quadrant bearings have - both numbers and names!      Look at the diagram! Consider the direction in which the green arrow is pointing. To get its azimuth, you measure the angle it makes with 0°. That angle is 103° (shown in parentheses). To get its compass quadrant bearing requires three steps. First, decide whether the arrow is closer to N or to S. You can see it's closer to the S. Next, decide whether it's closer to the E or the W. It's closer to the E. Finally, measure the angle between the arrow and the S. That angle is 77°. Now you have the compass quadrant bearing: S 77° E (shown in red). (You always write the N or S first, then the angle, and then the E or W.)"

 "That seems complicated!"

 "It is more complicated than the azimuth, but the advantage of the compass quadrant bearing is that it gives you the old-fashioned sense of north, northeast, etc. together with a precise angle!!"
 "Here's a diagram showing some more directional arrows. The table below shows their equivalent azimuths and compass quadrant bearings! A few extra equivalents are also shown in the table!"

 AZIMUTH 0° 27° 103° 178° 210° 270° 283° 340° COMPASS QUADRANT BEARING (due) N N 27° E S 77° E S 2° E S 30° W (due) W N 77° W N 20° W

 By the way, for azimuth 0° people often say 'due' north ('due' means 'exactly'), and for 90° they say due east, for 180° due south and for 270° due west!"

 "Now you try it Lou! To see if you've mastered the conversions between azimuths and compass quadrant bearings, take this little QUIZ!"