Well look what we have just north of the top of the flight path —
https://en.wikipedia.org/wiki/Warrenton_Training_Center
Warrenton Training Center (WTC) is a classified United States government communication complex located in the state of Virginia. Established in 1951, it comprises four discrete stations located in Fauquier and Culpeper counties.
WTC has served multiple roles, most notably as a Central Intelligence Agency (CIA) signals intelligence facility, numbers station, and communications laboratory. The center also houses at least one underground "relocation" bunker that serves U.S. continuity of government purposes, and is a communications and signals intelligence training school for various federal departments and agencies, including the CIA, National Security Agency (NSA), Department of Defense and Department of State. Additionally, it is a relay facility for the Department of State's Diplomatic Telecommunications Service. The United States Army administers WTC on behalf of the U.S. government.
Under the NCS (dissolved and functions transferred to the United States Department of Homeland Security in 2012[4]), the center is mandated to provide communication for the federal government under any circumstances, including a nuclear attack. Its underground bunkers house communications infrastructure that provides service for most major federal departments.[5] In 2002, the Brookings Institution listed an unspecified WTC "relocation bunker" as a facility with an active nuclear weapons, weapons-related or naval nuclear propulsion mission.
The CIA has used Warrenton Training Center as a communications facility since the 1950s.[3] Short-wave radio enthusiasts have identified WTC antennas broadcasting suspected intelligence transmissions.[7][8] In 1989, a WTC spokesperson acknowledged that the stations "are operated … to communicate with embassies, and for espionage transmissions" to American intelligence agents in Cuba and Central America.[9] In 1998, laboratories at WTC were reported to produce concealed radio equipment used to send and receive communications, typically in the form of furniture items.
Station A: 1.1 miles (1.8 km) SW of Warrenton (38.7040°N 77.8112°W)
Station B: 2.4 miles (3.9 km) NW of Warrenton (38.7335°N 77.8297°W)
Station C: 1.6 miles (2.6 km) SE of Remington (38.5195°N 77.7852°W)
Station D: 3.2 miles (5.1 km) NW of Lignum (38.4591°N 77.8487°W)