What’s going on with these UAV sightings?

Photo: Jeremy Poland / E+ / Getty Images

Photo: Jeremy Poland / E+ / Getty Images

It cannot be denied that people are seeing more objects flying in the night sky. It is suspected that these are unauthorized UAVs collecting information over U.S. and international military bases and, well, also over people looking up at the sky in their backyards at night. It is unlikely that these unidentified flying objects are causing much harm to the civilian population other than being a curiosity. However, it remains unclear what they might be doing over military installations.

In November and December 2024, numerous reports emerged of UAVs surveilling residential neighborhoods, restricted zones and critical infrastructure across the Northeast United States. This includes areas such as water storage facilities, transmission lines, railway installations, police departments — both local and federal — and military bases.

Military bases reporting UAV overflights included Wright-Patterson Air Force Base in Ohio, Picatinny Arsenal and Naval Weapons Station in New Jersey and Ramstein Air Base in Germany. In the UK, Royal Air Force (RAF) bases at Lakenheath, Mildenhall, Feltwell and Fairford in the South of England all reported unauthorized UAV overflight activity, which is somewhat concerning for nuclear weapons bases in Europe. Lakenheath appears to have scrambled F-15s to investigate one such UAV incursion.

Detecting and mitigating threats

In the United States, the increased intensity of UAV sightings has residents and Congress concerned, while various authorities claim that most of these incidents are harmless. A joint statement by the Department of Homeland Security, the Federal Bureau of Investigation, the Federal Aviation Authority (FAA) and the Department of Defense stated:

“Having closely examined the technical data and tips from concerned citizens, we assess that the sightings to date include a combination of lawful commercial drones, hobbyist drones, and law enforcement drones, as well as manned fixed-wing aircraft, helicopters, and stars mistakenly reported as drones. We have not identified anything anomalous and do not assess the activity to date to present a national security or public safety risk over the civilian airspace in New Jersey or other states in the Northeast.”

Nevertheless, these agencies reported, “Local commanders are actively engaged to ensure there are appropriate detection and mitigation measures in place.”

No other major announcements have followed these incidents, but it would seem logical that military bases have begun activating existing detection and defensive systems. Known countermeasures may include specialized radar, laser, optical, acoustic and radio frequency (RF) detection and defensive systems.

Radar always has been employed to detect airborne intruders, and the reflections from them appear on a display, which the ground user can then align with a range of potential defenses. However, UAVs are generally small, while conventional radar is designed to pick up hefty reflections from the surface of full-size commercial and military aircraft.

Photo: Robin Radar Systems

Robin Radar Systems

Robin Radar Systems in Holland has worked to refine radar that can detect small flying objects. Birds can cause havoc at airfields where aircraft take off and land at high rates, so detecting birds for airfield operators is one angle for which Robin Radar Systems has developed a reflection capability. A large bird and a UAV might be very similar in size. To differentiate the two, the company found a way to see a Doppler effect (speed differences) within a radar return, which indicates the spinning rotors of a UAV rather than flapping wings — a system they term micro-Doppler radar. This detection system works to find objects many miles away and at well-defined approach angles from the radar antenna. Therefore, these X-Band radars are mostly based at the places you want to protect, such as airfields. Some radars also can be packaged to be transportable, perhaps for military applications, where a temporary base needs to know if enemy attack UAVs might be on their way.

Other principal detection systems include “sniffing” RF frequencies to detect UAV control signals, but this has a shorter range than radar and does not easily determine distance or approach angle without several triangulating bases. Additionally, of course, UAVs without control signals cannot be detected with this particular RF technology. Optical systems using still/video/infrared (IR) cameras are good in daylight, but not so good in the dark. Acoustic systems use microphones or an array of microphones to listen for rotor sounds but have a shorter range (less than 1/3 of a mile).

Then, if you have suitable defensive capabilities, you could either take down an unwanted UAV by flying a counter-UAV to collide with and destroy it or by trapping it in a net. In a military situation, many UAVs have been shot down by various types and calibers of guns — and even by very expensive missiles. Electronic defenses include jamming guidance and/or control signals by transmitting signals that overcome and scramble the GNSS and/or control signal or by frying its electronics using high-power microwave transmissions or high-powered laser(s) — these last two systems are expensive and heavy, which makes them cumbersome.

Spoofing the on-board GNSS receiver by transmitting false satellite signals to steer the UAV away from its target recently has been used by Ukrainian forces to steer attack UAVs back into neighboring countries.

GNSS jamming is widely used, and there are numerous equipment suppliers; however, spoofing systems are less common due to their additional complexity and cost. Some RF systems can collect data from the opposing UAV and even detect where the operator might be located.

Of course, not all UAVs straying into restricted airspace come from operators with bad intentions — some might be “Sunday-driver” recreational UAV flyers who have allowed their UAVs to stray into the wrong area. This is another reason the FAA requires formal UAV operator training and certification for commercial operations, but this is not required for recreational UAV flyers.

DroneHunter drone net capture system. (Photo: Fortem Technologies)

FAA regulations

The FAA regulations for UAVs are fairly easy to understand, and it would probably take an intentional effort to fly unauthorized into restricted airspace. Otherwise, stay at or below 400 ft, don’t exceed 100 mph, don’t go where you shouldn’t, file a flight plan — ask permission using the automated FAA LAANC online tool — but always stay within visual range of the UAV. Those are most of the basics. Additionally, to operate a UAV commercially, you must also register it with the FAA and install an electronic device to tell everyone in the surrounding airspace the drone’s registration number, which is traceable to the owner/operator. Never fly near clouds, comply with local rules when flying recreationally, and never, ever fly into restricted airspace, particularly around airports, without prior authorization.

These multiple reported UAV incursions violate FAA regulations, so it is reasonable to assume the operators are deliberately flying illegally. Recreational flying requires the operator to see the UAV at all times — so flying at night is not legal either, as the rules state not to fly an hour after sunset or an hour before sunrise. Operators in restricted airspace are committing a crime punishable by fines and/or years in prison. Yet they still fly, so are they nuisance operators who don’t care or is the activity criminally motivated or orchestrated offshore?

Utilizing UTM

Would the coming unmanned aircraft system traffic management (UTM) have been able to keep these intruders away? I am not sure, but UTM is designed to manage UAV traffic, so presumably, it could manage these UAVs to comply with traffic requirements. However, these intruders are already ignoring existing laws, so UTM may more readily enable the identification of rogue UAVs and operators. Recent tests at the FAA/NASA UTM test range in North Texas have drawn huge interest from Walmart and Amazon, as they push to get UAV package delivery working. Wing now delivers for Walmart using a production UTM system in Dallas and Fort Worth, Texas.

To wrap this up, amongst many recently reported unidentified flying objects, several have been identified as probable UAVs, and some of those over restricted areas could be detected and managed with existing technologies. FAA regulations ban flights in restricted airspace unless approved — i.e., working in coordination with those ground facilities. There are UTMs for UAVs already being used commercially, which could assist in managing all UAVs.