BBC Sport looks back to 1988 and a controversial day at Royal Ascot. That day Royal Gait was first past the post in the Gold Cup but was controversially disqualified by the stewards for causing interference and placed last, with the horse who finished second, Sadeem, promoted to first place.
On the same day it was alleged that a horse called Ile de Chypre, when six lengths clear was targeted by ultrasound waves emitted by an adapted pair of binoculars. The horse veered off course and unseated its rider. No use of a stun gun was ever proved.
One of the jockey's riding that day Willie Carson, who is now part of the BBC racing team recalls the events.
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