What blimps are best at is having a psychological effect: making people feel like they’re being watched. Filmmaker Kirsten Johnson’s short documentaryThe Above touches on that phenomenon. The film, made for The Intercept’sField 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.
https://theintercept.com/2015/10/28/military-blimps-rampage-deflates-raytheons-hopes-to-sell-more/