I. Introduction
Unmanned aerial vehicles (UAVs) have been the pinnacle of research and focus upon providing an efficient medium for communication and surveillance application utilizing High-Altitude Long Endurance (HALE) UAVs. Recent years have brought renewable energy sources, such as solar panels to the surface as an alternate power source. Applications, such as airborne surveillance is still in demand for numerous operations; however, alternate modes of communications like airborne letter courier are vital in areas with intrusion and are of prodigious interest to assorted parties [1].