The Pentagon said Wednesday that U.S. fighter jets were tracking an unmanned Army surveillance blimp that tore loose from its ground tether in Maryland and drifted north over Pennsylvania.
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Two F-16 fighter jets from the Atlantic City Air National Guard Base in New Jersey were monitoring the craft, which was traveling north at an altitude of about 16,000 feet.
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The aircraft is known as a Joint Land Attack Cruise Missile Defense Elevated Netted Sensor System and can be used as part of a missile defense system.
http://www.startribune.com/fighter-jets-track-military-blimp-drifting-over-pennsylvania/338024901/?c=n&clmob=y