Military Gets Stratospheric Spy Airships

Military scientists this week got the go ahead to build a roughly 1/3-scale model of a stratospheric airship that if completed in-scale will basically house a floating 15-story radar system capable of detecting and tracking everything from small cruise missiles and unmanned aerial vehicles to soldiers and small vehicles under foliage up to 300 kilometers away.

The model is no slouch either and will consist of an airship containing an X-band radar system that will be roughly 100 square meters in size (half the size of a roadside billboard) and a UHF-band system that will be approximately 600 square meters in size (roughly equivalent to the size of a soccer field).

The Defense Advanced Research Projects Agency (DARPA) awarded Lockheed Martin Aeronautics a $400 million contract to design, build, test and flight-demonstration of the 1/3-scale airship that will be large enough to validate manufacturing and calibration for the objective system and will provide an early glimpse of the air and ground target tracking performance possible with an operational system. Demonstration flight tests are expected to occur in FY 2013, Lockheed said.

The model will test Raytheon's new, low-power density radar which is made up an active electronically scanned array antenna that will transmit on UHF and X-band from within the airship.

The airship project, known as Integrated Sensor Is Structure (ISIS) is developing the core technologies necessary to integrate this Raytheon sensor package that in the final version will be approximately 6,000 square meters in size (the size of 15-story building, integrated directly into the structure of stratospheric airships that will operate at approximately 70,000 feet, DARPA said.

The radar is the key to this phenomenal sensor package, DARAP said. As the radar aperture grows larger, the tracking performance of the radar system increases exponentially. DARPA's ISIS program takes advantage of the large amount of space available on a stratospheric airship to enable a very large radar aperture and provide a revolutionary level of performance. In addition, the program envisions operating the stratospheric airship using a satellite-like logistics model where the airship will be launched and operate autonomously for up to five years.

The planned capabilities of the ISIS project are straight out of a sci fi film - ISIS will provide a dynamic, detailed, real-time picture of all movement on or above the battlefield: friendly, neutral or enemy - a big picture map showing everything moving for hundreds of kilometers, DARPA said.