Disclosed is a switchable transmit and receive phased array antenna (“STRPAA”). As an example, the STRPAA may include a housing, a multilayer printed wiring board (“MLPWB”) within the housing having a top surface and a bottom surface, a plurality of radiating elements located on the top surface of the MLPWB, and a plurality of transmit and receive (“T/R”) modules attached to the bottom surface of the MLPWB. The STRPAA may also include a plurality of vias, wherein each via, of the plurality of vias, passes through the MLPWB and is configured as a signal path between a T/R module, of the plurality of T/R modules, on the bottom surface of the MLPWB and a radiating element, of the plurality of radiating elements, located on the top surface of the MLPWB opposite the T/R module.