A Monday news release from the DoE’s National Nuclear Security Administration (NNSA) explained that, beginning October 19, the federal agency’s Nuclear Emergency Support Team “will measure naturally occurring background radiation as part of standard preparations to protect public health and safety” in the months leading up to the presidential inauguration, scheduled for January 20, 2021.
The department stressed the chopper flyovers will “occur only during daylight hours” and will take an estimated two hours to complete evaluations in each area. The aircraft will travel “over the areas at 150 feet (or higher) above the ground at a speed of approximately 80 mph.”
“The aerial surveys are a normal part of security and emergency preparedness activities. NNSA is making the public aware of the upcoming flights so citizens who see the low-flying aircraft are not alarmed,” read the memo.
Locals unaware of the same-day announcement questioned why a helicopter was making loops above Silver Spring, Maryland, on Monday.
The lower pattern we've seen before frequently tied to surveying or lidar imaging pic.twitter.com/mtpBDCQGSy
— Helicopters of DC (@HelicoptersofDC) October 19, 2020
is this a news chopper or something? It keeps buzzing downtown silver spring. It’s dangerously low and just keeps going back and forth and back and forth. pic.twitter.com/bVL1ZxW1w0
— Ecological Apocalypse Now 🌹✊✡️ (@EcoApocalypse) October 19, 2020
Hearing multiple helicopters fly over downtown Silver Spring in the last 5 minutes. What’s happening? #SilverSpring #dtss #maryland
— Jessica Crosby (@jcroz713) October 19, 2020
Totally normal things happening over Georgia Avenue in Silver Spring. Olive green helicopter has been circling for about 10 minutes. pic.twitter.com/xzFFb2BRaS
— 👻 Competing Slates of Electors 🎃 (@Adam_Unger) October 19, 2020
YouTube footage uploaded by the NNSA shows the twin-engine Bell 412 chopper said to be equipped with “sensitive, state-of-the-art passive radiation sensing technology,” according to the October 19 release.
The helicopters are operated by the Remote Sensing Laboratory Aerial Measuring System via Joint Base Andrews in Prince George's County, Maryland.