The first of two radar blimps to protect the nation's capital from cruise missiles is being readied for operational transfer to a U.S. Army air defense unit.

The helium-filled aerostat system, called JLENS, is undergoing additional testing of its radar systems by its maker, Raytheon, following its recent raising in Maryland.

"JLENS is strategically emplaced to help defend Washington D.C. and a Texas-sized portion of the East Coast from cruise missiles, drones and hostile aircraft," said Dave Gulla, vice president of Raytheon Integrated Defense Systems' Global Integrated Sensors business. "JLENS can detect potential threats at extremely long ranges, giving North American Aerospace Defense Command more time to make decisions and more space to react appropriately."

The tethered radar Aerostats, each the size of a football field, will float at a height of 10,000 feet for 30 days at a time.

Raytheon said the second blimp in the system will take to the air early next year and that both will then take part in a North American Aerospace Defense Command exercise.