For all the C4ISR capabilities offered by fixed-wing UAS platforms, there is still a role for aerostats
or tethered balloons to carry out military reconnaissance and surveillance missions at high altitudes.
Advocates for aerostats claim the balloons can carry a diverse payload of EO, radar or even EW systems at a lower implementation cost than a fixed-wing uncrewed aircraft, and they can also be employed as communications relay hubs to improve signal transmission in mountainous terrain.
Examples include the Russian AVK-05 tethered aerostat equipped with EO sensors so that (under optimal conditions) it can survey a radius of 10km