Good piece in the Baltimore Sun from a few months ago about what a boondoggle this project has turned out to be: http://www.baltimoresun.com/business/federal-workplace/bs-md...

"But after 17 years of research and $2.7 billion spent by the Pentagon, the system known as JLENS doesn't work as envisioned. The 240-foot-long, milk-white blimps, visible for miles around, have been hobbled by defective software, vulnerability to bad weather and poor reliability."