Abstract: An antenna assembly for an active electronically scanned array includes, among other things: an array of antenna elements; an RF signal feed and circulator assembly coupled to said antenna elements and forming thereby an array of radiating structures; a generally planar RF manifold assembly having regularly spaced openings therein located behind and normal to the radiating structures; an array of T/R modules connected to the array of radiating structures and having respective RF connector assemblies forming a portion of an RF interface at one end portion of each of the modules which project upwardly through said spaced openings in the RF manifold and wherein the respective connector assemblies thereof connect to at least one immediately adjacent circulator as well as to transmit and receive manifold portions of the RF manifold; each of the T/R modules further have a heat sink plate on the back side thereof which is positioned against one of a number of elongated liquid coolant circulating coldplates connected