I used to work in Southwest DC a few blocks from the Capitol and down the street from the Navy Yard. One day a small plane like a Cessna was circling overhead the area for about half an hour before it left. Found this weird because we are part of the no fly zone so if he wasn't supposed to be there the plane should have been a smoldering wreckage on our playground. I hope the FBI got my pictures of their plane that I posted online asking what the hell it was.
Look, there are actual companies out there that fly drones over oil tanks to see how much oil each refinery has. I thought it was pretty well known that the government would have something way more advance and similar already in place.