Kelsall Hill Horse Trials, frangible pin: Frangible pins were first introduced as a safety measure into eventing in 2002. As their name suggests, these pins, inserted between the top rail of a cross-country obstacle and the uprights supporting it, are designed to break if hit with sufficient force and thus instantly collapse the top rail. This gives the horse a chance of getting a leg forward to save it from the dreaded 'rotational fall', where the force of hitting an unyielding obstacle can cause a horse to somersault over a fence and land on the rider. Rotational falls are far and away the commonest cause of serious injury and deaths among event riders.
<a rel="nofollow" class="external text" href="https://www.geograph.org.uk/profile/35615">Jonathan Hutchins</a>
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<a rel="nofollow" class="external text" href="https://www.geograph.org.uk/photo/4454332">SJ5567 : Kelsall Hill Horse Trials: frangible pin</a>, geograph.org.uk