Air Transport

Northrop Grumman and Raytheon are to develop technology for extremely large, but lightweight phased-array radars to be integrated into the structure of a stratospheric surveillance airship able to stay on station for a year or more.

Under the US Defense Advanced Research Projects Agency’s (DARPA) Integrated Sensor Is Structure (ISIS) programme, Northrop has received $8.7 million, and Raytheon $8 million, to develop low power-density active electronically scanned array (AESA) technology for a dual-band radar to be bonded to the flexible hull of the airship.

Northrop has also received $6.9 million to develop a DC-efficient transceiver to minimise the power required for the active-array radar, while Lockheed Martin has received $8.8 million to develop the airship’s power generation system, “most likely solar-regenerative supplemented by fuel for peak power consumption”, the company says.

DARPA’s ISIS programme aims to demonstrate technology for an unmanned airship capable of maintaining station for a year or more, carrying a UHF/X-band AESA providing simultaneous air and ground moving-target indication out to a radar horizon of 600km (325nm) from a 70,000ft (21,000m) operating altitude.