In the sky - it's a bird!  It's a plane!  It's...a drone.  Congress is learning more about domestic concerns of remotely-piloted aircraft.

FOX News Radio's Jared Halpern reports from Washington in our ongoing series on national security:

The Federal Aviation Administration wants to create half a dozen drone - or Unmanned Aircraft System - test sites around the country.

(Dr. Toner) "We expect to learn how UAS operate in the different environments and how they impact air traffic operations."

...Dr. Karlin Toner with the FAA.  The military relies heavily on drones to carry out strikes overseas, but here on the homefront, the unmanned aircraft could be used by police for surveillance, or by ranchers or farmers to easily check on livestock and crops.

Privacy advocates warn of a "surveillance society."

In Washington, Jared Halpern, FOX News Radio.