WASHINGTON — One of two tethered US Army aerostats that can be seen floating above Aberdeen Proving Ground, Maryland, has broken free from its tether and is moving in a northeast trajectory.

The Joint Land Attack Cruise Missile Defense Elevated Netted Sensor System (JLENS) consists of both a fire control system aerostat and a surveillance aerostat and is undergoing operational exercises at Aberdeen Proving Ground.

The surveillance aerostat detached from its mooring station at 12:20 p.m. EST today, NORAD spokesman Michael Kucharek told Defense News.

The aerostat was last seen traveling over Pennsylvania and is being trailed by two F-16 fighter jets from Atlantic City, New Jersey, Kucharek said.

The first blimp, carrying a suite of surveillance sensors, was launched in December 2014.

The second in a pair of Army aersotats designed to help defend against missile attacks was launched just a few months ago over the suburban Baltimore area in a test that is supposed to last several years. JLENS is designed to track cruise missiles, aircraft, boats and vehicles from Boston to Norfolk, Virginia, and feed targeting information to missile defense systems.

It was nearly canceled a few years ago, when the Army cut its planned buy of the Raytheon-made system from 16 to just two.

Email: jjudson@defensenews.com

Twitter: @jenjudson

Jen Judson is an award-winning journalist covering land warfare for Defense News. She has also worked for Politico and Inside Defense. She holds a Master of Science degree in journalism from Boston University and a Bachelor of Arts degree from Kenyon College.

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