The Airship as Battlefield Sensor:

The Air Force Research Laboratory has awarded a pair of contracts, to Lockheed Martin and Raytheon respectively, as part of the Integrated Sensor Is Structure (ISIS) program—leading to a stratospheric airship operating at 70,000 feet as a surveillance platform with an autonomous unmanned sensor. The two-year contracts ($10.2 million for Lockheed and $7.9 million to Raytheon), which DARPA is funding, are for work on an advanced hull material (Lockheed) and a lightweight active electronically scanned array (Raytheon). Northrop Grumman previously won a contract to provide a different sensor technology approach. The resulting platform is to be able to tract advanced cruise missiles from 370 miles away and enemy combatants on the ground 200 miles away.