A Turn for the Worst - how to assess a bend

Have you ever found yourself braking in a bend simply because it was sharper than you originally thought?

If you have, then have a think about how you actually go about assessing the severity of bends. If you get it wrong, the consequences are potentially very serious, particularly on rural roads, which still dominate crash statistics.

And it is not just young, inexperienced drivers who get “caught out” by bends. It is here that, in the jargon, most “single vehicle accidents”take place.

There are a number of clues we can take from the environment to help us. The most obvious are the road signs and markings. There are other less obvious ones: the line of the trees, hedges, buildings, street lights or telegraph poles (although remember that sometimes telegraph poles run through fields, so don’t follow them!).

The actual width of the road can be a factor: the narrower it is, the less space you have to manoeuvre. Skid marks on the road are an indication of past mistakes. The position and speed of other traffic can also provide you with valuable information. Another particularly useful way of assessing a bend is to use the “limit point analysis”.

The limit point is the furthest point which you can see, i.e. where the left and right hand sides of the road meet. To use this technique first make sure that you can stop before you get to it, then simply ask yourself: is it getting further away? If it is and you can see further ahead, then your speed should be fine. On the other hand if it is getting closer, then you could continue to reduce speed until the limit point begins to move with you and your view opens up again.

This technique takes a bit of practice but it will help you to link your speed with your range of vision and allow you to stop in the distance seen to be clear. And in roads where you can’t see through the bends it gives you a reliable and practical solution to a difficult judgement problem.

This article has been reproduced with the permission of the IAM (Institute of Advanced Motorists)