The 4.2-mile stretch of Las Vegas Boulevard South, home to a concentration of resort hotels and casinos, is known as The Strip. Each New Year’s Eve, it draws massive crowds, with estimates for the Strip and downtown Las Vegas reaching 400,000 people.
The gathering known as “America’s Party” closes the boulevard to traffic, turning the Strip into a massive pedestrian party zone. This year will also include eight minutes of fireworks and, for the first time, an LED drone light show.
Yet, even before the fireworks go off or the drones fly overhead, helicopters will conduct low-altitude flights over the Las Vegas Strip and surrounding areas from Monday through Wednesday, ahead of the New Year’s Eve celebrations.
Conspiracy Theorists Take Note
The helicopters will be part of the National Nuclear Security Administration’s (NNSA’s) Nuclear Emergency Support Team (NEST) Aerial Measuring System (AMS) to measure expected background radiation as part of standard preparations to protect public health and safety during the event, the Department of Energy announced. NEST is an element of the USA’s nuclear and radiological emergency response capability.
Such flights are likely to catch the attention of the public, and probably a few conspiracy theorists, which is why the DOE has made clear why the aircraft are making the low-level flights over the famed strip.
“The public may see a Leonardo AW-139 helicopter, which is equipped with radiation-sensing technology. The helicopter will fly at relatively low levels,” the NNSA explained.
The DOE’s NNSC conducts such aerial radiation assessment surveys as part of “normal and routine” security assessments to ensure emergency preparedness activities.
“NNSA is making the public aware of the upcoming flights so citizens who see the low-flying aircraft are not alarmed,” the agency added.
NNSA At Major Events
It isn’t just in advance of New Year’s Eve that the NNSA conducts such flights. Its helicopters frequently fly over Las Vegas for routine aerial radiation surveys. The helicopter made similar flights in November in advance of the Las Vegas Grand Prix.
Similar flights will be made in the days leading up to the Super Bowl, which will be played at Levi’s Stadium in Santa Clara, California, on February 8, 2026. Significant events such as marathons and large conventions also involve the NEST conducting flights in a grid pattern at low altitudes of 150 to 300 feet and at speeds around 80 mph.
Flights are also conducted during daylight hours to identify any unexpected radiation sources that might pose a threat during the event.
The AMS flights began in 1958, when the Aerial Radiological Measuring System (ARMS) was established to support the U.S. Geological Survey.
“The first operational use of this capability occurred in support of atmospheric nuclear weapons testing at the Nevada Test Site, when ARMS aircraft mapped the distribution of radioactive material,” the DoE explained. “After U.S. nuclear testing moved underground, ARMS was used to confirm that radioactive materials were not released into the atmosphere.”
According to the DOE, the AMS aircraft “are outfitted with state-of-the-art communications and radiation detection systems.” The aircraft’s capabilities ensure that AMS science teams on board can communicate in real time with experts at the National Laboratories and support rapid, protective-action decisions.
The current AMS fleet includes three Beechcraft BN-350 Extended Range fixed-wing aircraft and two Leonardo AW-139 rotary-wing aircraft, which are stationed as needed at Joint Base Andrews, Maryland, and Nellis Air Force Base (AFB), Nevada. The AW-139s replaced the NNSA’s aging fleet of Bell 412 helicopters, which had served as “nuclear sniffers” since 1996.
In 2022, Leonardo was awarded a DOE contract for the two AW-139 aircraft, which were delivered to the NNSA in 2024. The helicopters are now in service in more than 70 countries, used for search and rescue, air ambulance, law enforcement, firefighting, disaster relief, and defense duties. Intermediate-twin-engine rotary aircraft are also used in the offshore transport sector, VIP, government, and corporate transport, in addition to other civil missions.
