>>The first aerostats were assigned to the United States Air Force in December 1980 at Cudjoe Key, Fla. During the 1980s, the U.S. Customs Service operated a network of aerostats to help counter illegal drug trafficking. Their first site was built at High Rock, Grand Bahamas Island, in 1984. The second site was built at Fort Huachuca, Ariz., in 1986. Before 1992, three agencies operated the TARS network: the Air Force, U.S. Customs Service and U.S. Coast Guard. Congress in 1992 transferred management of the system to the Defense Department, with the Air Force as executive agent. Under Air Force management, through contract consolidation and system standardization, the operations and maintenance cost per site was reduced from $6 million in fiscal year 1992 to $3.5 million in 2007.[citation needed] However the Budget Control Act of 2011 slashed funding for the Air Force, which tried to shut down the project.[3] However, the Department of Homeland Security picked up the project and its funding for fiscal year 2014.[4]
edit: PS, the Aerostat/Blimps have been listed on aviation sectionals as well, so no, they don't file flight plans.
Do you mean that they first started testing them in DC ca ~2005? Because they have been around for decades. https://en.wikipedia.org/wiki/Tethered_Aerostat_Radar_System
History
>>The first aerostats were assigned to the United States Air Force in December 1980 at Cudjoe Key, Fla. During the 1980s, the U.S. Customs Service operated a network of aerostats to help counter illegal drug trafficking. Their first site was built at High Rock, Grand Bahamas Island, in 1984. The second site was built at Fort Huachuca, Ariz., in 1986. Before 1992, three agencies operated the TARS network: the Air Force, U.S. Customs Service and U.S. Coast Guard. Congress in 1992 transferred management of the system to the Defense Department, with the Air Force as executive agent. Under Air Force management, through contract consolidation and system standardization, the operations and maintenance cost per site was reduced from $6 million in fiscal year 1992 to $3.5 million in 2007.[citation needed] However the Budget Control Act of 2011 slashed funding for the Air Force, which tried to shut down the project.[3] However, the Department of Homeland Security picked up the project and its funding for fiscal year 2014.[4]
edit: PS, the Aerostat/Blimps have been listed on aviation sectionals as well, so no, they don't file flight plans.