Leonardo Nerio ULR

The Nerio ULR from Leonardo (Italy) is an electro-optical surveillance and target acquisition system of very long range. It works in daylight and infrared mode, and the thermal imager is called Horizon. In the Falcon Shield system it serves as the optical sensor. The design is fixed, and a mobile variant called Very Long Range is named alongside; the military is the field of use.

For the detection of Class 1 drones the manufacturer states more than 16 km. Class 1 means, under the NATO classification, unmanned aircraft up to 150 kg; the span therefore runs from the smallest drones to large systems, and the achievable distance depends strongly on target size. As with all optics, detecting succeeds at greater distance than classifying and identifying, which need markedly more pixels on the target. The line of sight limits range: Earth's curvature, terrain, haze and heat shimmer.

As a passive sensor the system itself emits no radio signals and is in that respect legally uncritical. Data protection has to be observed when recording: at ranges of this order people and property far outside the protected site also come into the picture, and recordings fall under data protection law (in the EU the GDPR). Defeating a drone remains reserved for the competent bodies (in Germany under Section 15a LuftSiG, in Poland under Article 156ze of the Aviation Law).

In selection, integration counts before the range figure: such a sensor shows its value as part of a system like Falcon Shield, in which radar or radio detector usually assigns the target and the optics confirm. Wear concerns the pan and tilt mechanics and the window, and in thermal cameras, depending on design, cooling and calibration; the alignment to the cueing sensor must be checked regularly. Weather, light and drone size determine the achievable distance.