Lockheed has developed an unmanned lighter-than-air vehicle that would operate above the jet stream and above severe weather in a geostationary position to serve as a telecommunications relay, a weather observer, or a peacekeeper from its over-the-horizon perch.

According to the North American Aerospace Defense Command (NORAD), 11 high-altitude airships would provide overlapping radar coverage of all maritime and southern border approaches to the continental U.S., and may be a significant asset in homeland defense efforts. The Stratospheric Platform System (SPS) dirigible operates just barely within the outer limits of the earth’s atmosphere and is emerging as part of the military’s 21st century transformational mindset.

SPS is an unmanned, powered airship that can maintain a relatively geostationary position at 70,000 feet. Lift is provided by helium that is contained in its envelope. Differential thrust, electric-powered props control the pitch and roll and keep it in position. With the advent of thin-film photovoltaic solar cells (capable of producing voltage when exposed to radiant light), commercially available fuel cells, and lightweight/high-strength fabrics, a high-altitude airship could stay on station weeks or even months at a time by generating its own power and keeping helium loss to a minimal amount.

On station, the onboard sensors’ surveillance coverage extends over the horizon and monitors a diametric surface area of 775 miles. At nearly 500 feet long and 150 feet in diameter at its widest girth, the airship’s volume exceeds 5 million cubic feet.

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