The present invention relates to an impingement cooling apparatus for use in the removal of heat from a heat liberating device. The apparatus includes a housing on which the device is secured and a stack of plates fitted within the housing. One of the plates is an impingement orifice plate adjacent the housing where the device is located. The orifice plate has a region that is characterized by coolant flow impingement orifices passing therethrough. The orifice plate also has a coolant drainage return adjacent the impingement orifice region.