In what may be the most bizarre and public crash of a multibillion-dollar Pentagon boondoggle ever, a surveillance blimp flying over an Army base in Maryland broke loose Wednesday afternoon, its 6,000-foot-long tether wreaking havoc on the countryside before it finally came down in pieces in Pennsylvania.

The giant airship — 80 yards long and about the size of three Goodyear blimps — was one of a pair that represented the last gasp of an 18-year, $2.7 billion program called JLENS, or “Joint Land Attack Cruise Missile Defense Elevated Netted Sensor System.”

There were once supposed to be 36 of them, their high-resolution 360-degree radar coverage up to 340 miles in any direction protecting the nation from cruise missiles.

But costs inflated, doubts about their utility mounted, and the program was scaled back and almost killed.

Blimps, it turns out, have had mixed success in purely military terms. When equipped with cameras, they are highly effective at conducting surveillance — but the Army promised there were no cameras on the JLENS blimps.

What blimps are best at is having a psychological effect: making people feel like they’re being watched. Filmmaker Kirsten Johnson’s short documentary The Above touches on that phenomenon. The film, made for The Intercept’s Field of Vision project, mostly shows a U.S. military surveillance balloon floating on a tether high above Kabul, Afghanistan. But it ends with shots of the JLENS.

Finally, the Army agreed to launch two of them, for a three-year test. They were hovering at a height of 10,000 feet just off Interstate 95, about 45 miles northeast of Washington, D.C., and about 20 miles from Baltimore. In theory, they could track moving objects from North Carolina to Boston, or an area the size of Texas. With only two in the air, they effectively cost about $1.4 billion each — a lot, even by advanced weapons standards.

While the blimps became perhaps the Pentagon’s most visible white elephants, their manufacturer, Raytheon Co., still hoped to make some more money off them.

The huge defense contractor’s endgame, at least until Wednesday, seemed to be trying to sell them abroad.

In a video interview with Shephard Media just two weeks ago, Douglas Burgess, director of persistent surveillance programs at Raytheon, discussed the JLENS program. “There’s a lot of interest internationally, particularly now that we’re up and flying,” he said. “I can’t talk specifics about who, but there is certainly a lot of interest internationally.”

As for his next step? “For us, it’s to get the A+, I call it, on the scorecard from NORAD about its operational utility here on the East Coast. So that’s really our near-term focus.”