Original URL: http://www.theregister.co.uk/2009/02/13/jlens_cdr/

Networked radar barrage balloons pass milestone

Poor man's defence against poor man's missile

By Lewis Page

Posted in Science, 13th February 2009 11:17 GMT

US-based weapons globocorp Raytheon was pleased yesterday to announce a successful Critical Design Review for its planned flotilla of cruise-missile-busting network spyeye barrage balloons.

Raytheon prefer to call the digital blimp barrier system JLENS, for Joint Land attack cruise missile defense Elevated Netted Sensor system. The idea is to put radars and communications gear high in the sky aboard moored aerostats. This will allow the sensors to peer down and spot low-flying enemies - such as cruise missiles - while they are still below the horizon for normal groundbound radars. The comms would also provide line-of-sight over much larger areas, offering improved network bandwidth for US ground force in the balloons' footprint.

Apparently the US Army, sponsors of the JLENS idea, are chuffed as can be.

"JLENS is moving forward," said Lt Col Stephen Willhelm of the US Army Program Executive Office for Missiles and Space. "The JLENS design review ... reaffirms our continued confidence that this critical cruise missile defense capability is on track."

Elements of the US military are concerned about the worldwide proliferation of low-flying, cruise missile type threats - perhaps as basic as a suicide-piloted light aircraft stuffed with homemade explosives. There are already ways to defend against these - for instance an AWACS radar plane can detect such targets from afar, and US fighters can then easily destroy them. But AWACS and fighters are pricey, even more so when you consider their limited endurance and the need to provide a large fleet in order to guarantee continued airborne watch. By contrast, JLENS balloons are cheap and can stay up for thirty days at a stretch.

In addition to comms and detection of cruise missiles, Raytheon say that the JLENS balloon-radars will be able to track ground targets just as airborne roboplanes and surveillance craft can. The company even suggests that JLENS will be able to track bigger artillery munitions - such as "large caliber rockets" - in flight.

The balloons themselves won't be armed, though one type will carry a fire-control radar. Rather, they will pass targeting information to other weapon systems such as Patriot missile batteries.

India has already deployed Israeli-made aerostat radars, in order to guard against possible low-flying air raids by the Tamil Tiger improvised rebel air force in Sri Lanka. ®