Triads, flocks of conics and Q(-)(5,q)

We show that if an ovoid of Q (4,q), q even, admits a flock of conics then that flock must be linear. It follows that an ovoid of PG (3,q), q even, wh ich admits a flock of conics must be an elliptic quadric. This latter resul t is used to give a characterisation of the classical example Q(-)(5,q) amo ng the generalized quadrangles T-3(O), where O is an ovoid of PG (3,q) and q is even, in terms of the geometric configuration of the centres of certai n triads.