A technique for use when the control has been placed on a line feature such as a stream or earth wall and you approach it across country.
The approach to such a control is often at right angles and, unless you are very lucky, you are unlikely to hit it spot on. In such cases it is essential to know which side of the control you are when you reach the line feature.
It is therefore better to aim deliberately (aiming-off) to one side of the control so that when you reach the line feature you know which way to turn to reach the control without wasting time.
Which side do you aim-off to? Well that might be a matter of choice and doesn’t really matter. However, your choice might be influenced by the terrain shown on the map. Some orienteers always prefer to aim-off to the right because they feel this is the way they normally 'drift'.
This technique means you may cover a little extra distance but it is well worth adopting. If you take a bearing hoping to hit the control perfectly and the control isn’t in sight then you have no idea which way to turn. You will be surprised how much 'drift' you can get on a direct bearing over a distance of 400 metres or so.
Top tip from Chris Baker (M80)
I read the notes on aiming off, particularly as to which "side" to choose. I think it's worth adding that it might well be worthwhile aiming off to the side where you consider that you might meet orienteers coming away from that control on their way to the next control.