The design of an S-band aperture coupled microstrip antenna array for use on airborne telemetry platforms is presented. The High Sensitivity Diverse Tracking Antenna (HSDTA) is capable of receiving both left and right hand circular polarizations and has RF auto-tracking capability. Novel placement of RF terminations throughout the design allows for HSDTA to be installed in multiple configurations aboard different airborne platforms while maintaining consistent mechanical mobility and high sensitivity. The HSDTA was successfully simulated, fabricated, and deployed. Measured RF performance, including the operational bandwidth, gain, and sensitivity, are discussed and compared to the simulation. The HSDTA was designed to withstand the environmental conditions present while flying at altitude. The system has been successfully used to collect telemetry while deployed on an airborne platform flying over the South Pacific at 35000 ft.