A dual-beam, dual-polarized wide-beam scanning phased array is designed, fabricated, assembled and tested at Ku-band for airborne sensing and communication applications. Compared with a prior proof-of-concept COTS-based phased-array, this demonstration uses custom MMICs to doubles the number of beams, double the transmit power output, increase the grating-lobe free beam scanning range from 50° to 60° and add additional array functionality. Custom MMICs and ASICs add more phase- and amplitude-bits and more than 20 dB in amplification significantly stressing transition matching, grounding and cavity mode suppression requirements. A custom seal ring over the entire array helps to choke-out cavity modes and increases isolation to ensure electronic stability across the aperture. The metallic seal ring also removes heat away from the electronics. A 120° dual-beam scanning volume on receive and switchable beams on transmit has been demonstrated and used on a wide range of sensor and communication applications.