Army Investigating Runaway Surveillance Blimp

Investigators are trying to find out how an Army survelliance blimp escaped a military base, leaving 27,000 people without power.

The 240-foot helium blimp escaped from a military facility in Maryland and drifted for 3.5 hours.

The craft, better known by its name JLENS (Joint Land Attack Cruise Missile Defense Elevated Netted Sensor System), is a tethered airship which floats 10,000 feet in the air. The blimp, which is nearly as long as a football field, can carry powerful radars that can protect an area roughly the size of Texas from airborne threats, CNN reports.

Two F-16s from a National Guard base in New Jersey were used to track the big, white craft as it floated away because aviation officials feared the blimp would endanger air traffic.

The craft did eventually deflate and touched down in Moreland Township, Pennsylvania. Navy Capt. Scott Miller, a spokesman for the nation's air command, said there was an auto-deflate device aboard, but it was not deliberately activated, and it is unclear why the craft went limp.

Military officials say blimps like this are normally used to detect hostile missles and aircrafts and have been used in the Iraq and Afghanistan wars.