[Scan-DC] USPP helo N11PP flight path

[Albert LaFrance]

I'd expect it to be over DC right now, but instead (at 20:49) it's circling
Fort Washington, having turned south over the Potomac after almost
completing a counter-clockwise loop around the Beltway, starting from its
base in Anacostia.  Interestingly, at Cabin John it took a detour NW along
the river and did a couple of loops around Olmstead Island at Great Falls
before heading back to the Beltway.