FOD
The possibility that something had interfered with the control was reviewed at the Inquest. A number of witnesses discussed past incidents with yaks and foreign objects. The Coroner requested that he needed evidence beyond reasonable doubt that no object had penetrated the FOD barrier and thus disabled the bell crank in the tail of the Yak. This required an extensive diving exercise by the dive unit at the QPS. It was confirmed at the inquest that the FOD had not been penetrated by any object.