Could we be using the wrong type of frangible pins on cross-country fences?

A new paper produced by a Swedish engineer suggests that the answer is yes.

Anders Flogård, the designer of the MIM safety pin and clip, has produced a document with diagrams that show how the physical forces that come into effect when a horse hits a fence while travelling forward and upward — as they would be in the take-off phase of a jump — are such that a reverse clip or pin on the back of a fence is far more likely to prevent a rotational fall than a traditional pin, which Anders believes may even accentuate the mistake.

The paper explains that when a rotational fall occurs, the forces on the horse are first horizontal and then vertical.

A traditional frangible pin positioned at the front of a fence is unable to move horizontally on impact as the upright posts prevent it from doing so. If the vertical — but not the horizontal force — is taken away as the pin is triggered, the distance between the rotational centre and the horse’s centre of gravity is reduced, which increases the rotational speed.

But with reverse frangible technology the fence is able to be driven forwards in the same direction as the horse. As the horse’s legs are never completely trapped the rotational speed is reduced. This means the horse will have a chance of recovering and staying on its feet.

Andy Griffiths, chairman of the International Event Officials Club (IEOC), said that the paper had been circulated to all members of the IEOC and had garnered “positive feedback”.

The issue, he said, is that the FEI is failing to act on new research such as this.

“The FEI needs to take the lead in safety research. It should not be left to national federations to try and persuade their umbrella organisation to be proactive,” he stated.

Course-designer Eric Winter, whose tracks include Blenheim and Hartpury, said that although reverse frangible technology is proving to be superior to traditional methods of pinning, much depends on the type of fence.

“There is no doubt that frangible pins have saved lives,” he told H&H. “But a method of pinning that is suitable for one type of obstacle might be inappropriate for another.

“It is vitally important that we keep looking at new ways to make the sport safer but, equally, there has to be sufficient expertise on the ground to implement new technologies.

“Education of officials and course-designers at all levels is therefore crucial.”

Cost is another prohibiting factor, said Eric.

“The sport simply hasn’t the budget to be spending vast sums of money on research and testing. It is not Formula 1,” he said.

The FEI’s Catrin Norinder said: “The FEI will review all new studies and research that will help the development of the risk management of eventing, together with the national federations.”

This news story was first published in H&H magazine (16 October 2014).