WASHINGTON, Dec. 17 (UPI) -- The North American Aerospace Defense Command plans to launch a massive surveillance blimp just outside Washington, D.C., on Friday.

The tethered blimp, or aerostat, is called the Joint Land Attack Cruise Missile Defense Elevated Netted Sensor System, or JLENS, and is carried by a 242-foot balloon. The Raytheon-built aerial monitoring station can stay elevated for up to a month at a time and has a high-definition 360-degree radar capable of monitoring 340 miles in any direction. The JLENS "orbit" consists of two units, one with long-band radar and one with X-band radar.


The first unit was on display for a demonstration at the Aberdeen Proving Ground in Maryland on Wednesday. It will be launched on its three-year test mission Friday, with the second unit to launch at a later date.

While JLENS has proven effective at detecting cruise missiles and ground-based threats including swarming boats, the system can easily monitor for other threats, including drones.

"The truth is, today the United States has no dedicated defense system to protect the American homeland against cruise missiles and rogue aircraft -- except JLENS," retired Air Force Col. Gerald M. May told Defense One.

"Besides detecting missiles, the mission of JLENS includes monitoring all air traffic," he said. "Rogue aircraft, off-course aircraft and unidentified aircraft will be quickly detected and reported by JLENS to appropriate authorities for action they deem fit."

During testing the JLENS included an infrared camera that successfully monitored human movement from the air. Privacy advocates got involved, and the Army has since said the aerostats won't be equipped with the Raytheon-built MTS-B camera.

Although possibly a behavioral deterrent, as the massive balloons will be visible to people on the ground, officials say JLENS is not a threat to Beltway residents' privacy as it lacks the cameras and other recording equipment necessary for individual monitoring.

"I'm sure that the people who are giving us these assurances mean everything they say, but the nature of government programs and government agencies is that things tend to expand and privacy protections tend to shrink," Jay Stanley of the American Civil Liberties Union objected to The Intercept.

"If we're going to have massive blimps hovering over civilian areas, or within radar-shot of civilian areas, then we need some very ironclad checks and balances that will provide confidence that there's no domestic surveillance going on," he said.

The JLENS program has cost some $2.8 billion so far, and Congress last week approved $43.3 million for the first year of the test.

The Department of Defense has invested billions in a number of lighter-than-air technologies in recent years, including airships and aerostats, such as the Persistent Ground Surveillance System (PGSS) and Persistent Threat Detection System (PTDS) used in Afghanistan. Domestic agencies including Customs and Border Protection deploy aerostats and airships for monitoring.