Ukraine CoA is adaptation of the symbol of Vladimir of Kiev (960-1015). There are several hypotheses about the meaning of the symbol. A common hypothesis is that the symbol describes a sky-diving falcon. On one side of Vladimir’s coin displays the symbol, on the other side probably Vladimir himself who doesn’t wear crown. Vladimir held title of Velykiy knyazʹ of Kiev. There was no tradition of wearing crowns by Grand princes in Rus.
PS Knyaz’ Vladimir brought Christianity to Kiev and Rus.