Citizens Ass'n of Georgetown v. Fed. Aviation Admin.

Tatel, Circuit Judge:

*427For decades, airplanes departing from Ronald Reagan Washington National Airport ("National") followed a route that took them over northern Virginia and the west bank of the Potomac River. In December 2013, after studying proposed route changes and finding that they would have no significant environmental impact, the Federal Aviation Administration (FAA) approved new flight paths that would bring planes closer to the Georgetown neighborhood of Washington, D.C. In the following months, pilots occasionally departed from National along the new routes. In June 2015, after…