Contouring Technique

Posted on Fri, 3rd February 2012 by Bill Brown
Off-topic

Keeping On An Even Keel

In April Richard Arman wrote a very interesting piece about contouring round hillsides. He found a compass helpful and I am going to try his approach. The method I find works for me relies on judgement only.

Typically you have just found your control half way up a rather long steepish slope, well away from the top and bottom. The planner has now set you the problem of finding your next control, perhaps 200 meters away across the hillside at the same level at which you now are. The hillside can be heavily forested or a bare mountainside. What to do? What I do is to look as far ahead as I can see and I judge what is a level line along the hillside. Then I choose the base of a tree or a clump of grass which is on that line but only about 50 metres away, or less if I can’t see that far. I focus on that point and make my way exactly to it. Then I do it all over again and again. Its quick and certainly not exact but for me I find it surprisingly effective. But you must always remember that you are making small height errors all the time, so if there is a feature at your height on the way or nearby, be sure to lookout for it. It always worth changing height a little to gain this reassurance. Of course I pace count to help me look for these signposts but then I tend to pace-count instinctively all the time. I get really bored with myself sometimes!

Anyway, try it yourself and see if it works for you. I find it works particularly well on rocky hillsides where you have to go up and down round outcrops all the time just to make progress and it is very easy to lose large amounts of height without realising it.

That is not the end of the story however. The clever planner will, if he can, place your next control not at the same level as your present one but at 3-5 contours above or below it. This is enough to stop you seeing it if you contour to it on the level. What I do is very simple minded because I always get it badly wrong if I set out contouring but climbing or dropping ‘a bit’ as I go. Instead I now climb or drop the contour difference right at the start, which may be slow. Then I contour at the new level as fast as I can go.

How to climb or drop 3-5 contours? Again pretty crude. To climb, I look directly ahead at the hillside and up ‘a bit’. I identify a tree base or clump or grass directly in this line of sight and climb up to it. I stand exactly on that point and repeat the exercise. I have now climbed one contour (5m or 16ft). Dropping down is not so easy. I look down and guess where my height plus a ’a bit’ might be and make for that exact spot etc. etc. If you are young or vertically challenged, you can use ‘a bit less’ than your height as your yardstick but use 3 of these per control interval. Crude or not it works for me. Try it yourself. Has anyone else got a ‘secret’ method which they might like to share?

By the way, on a steep hillside, you are nearly always more likely to spot a control flag if you are above it than if you are below it. May the O-Force be with you!

Bill Brown

 

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Orienteering Club