The Indian Air Force (IAF) has officially strengthened its national airspace security by adding the Russian-made 55Zh6ME Nebo-UM radar to its arsenal.
Recently spotted during the IAF’s Vayu Shakti 2026 exercises, this mobile, three-dimensional (3D) Very High Frequency (VHF) system is a significant upgrade to India’s layered air defence shield, designed specifically to track incoming stealth fighters, cruise missiles, and ballistic projectiles over vast distances.
Traditional fire-control radars generally use higher frequencies like the X-band or Ku-band, which modern stealth aircraft are engineered to evade. In contrast, the Nebo-UM operates in the VHF spectrum (133–144 MHz and 216–225 MHz).
Because it uses meter-long radio wavelengths, the radar waves interact differently with the physical shape of stealth jets, rendering their radar-evading designs much less effective and making them highly visible to operators.
Developed by Russia's Nizhny Novgorod Research Institute of Radio Engineering (NNIIRT), the Nebo-UM provides critical early warning capabilities.
Operational data suggests that under ideal conditions, it can spot stealth platforms—such as China’s advanced J-20 and the upcoming J-35—from over 250 kilometres away.
For conventional aircraft and ballistic missiles, its tracking range extends up to 600 kilometres, granting the IAF vital time to respond to potential attacks.
As the newest export variant of Russia’s renowned Nebo radar family, the system brings major technological leaps to the battlefield.
It is equipped with modern digital signal processing that effectively filters out ground clutter and suppresses enemy electronic jamming, ensuring reliable tracking even in heavily contested and hostile electromagnetic environments.
While older VHF systems could only provide a two-dimensional look at the skies, the Nebo-UM is a fully 3D surveillance radar. It simultaneously calculates the exact distance, direction (azimuth), and altitude of a target. This comprehensive situational awareness allows the system to instantly pass precise coordinates to the engagement units of the integrated air defence network.
A major operational advantage of this new radar is its seamless ability to work either on its own or as a key node in a wider, network-centric defence grid.
Once the Nebo-UM picks up a distant threat, it can instantly share that tracking data with long-range surface-to-air missile batteries, including advanced systems like the S-400, allowing their engagement radars to lock on much faster.
To ensure its survival during a conflict, the entire Nebo-UM system is mounted on high-mobility, heavy-duty military trucks. This design allows the crew to deploy the radar rapidly and relocate it to new positions within minutes.
This "shoot-and-scoot" mobility makes it extremely difficult for enemy forces to locate and destroy the system during active combat operations.
The deployment of this advanced radar is a timely move for India, given the increasing presence of stealth aircraft across the Indo-Pacific region.
Although stealth technology successfully shrinks a plane's radar signature against standard high-frequency sensors, the physical dimensions of these jets closely match the meter-long wavelengths emitted by VHF radars.
This physical interaction creates strong radar reflections, guaranteeing early detection long before the target can approach Indian airspace.
The Nebo-UM is part of a distinguished lineage of Russian anti-stealth technology.
It builds upon the foundations of earlier models like the mobile Nebo-SVU, which pioneered Active Electronically Scanned Array (AESA) technology in the VHF band, and the Nebo-U.
The UM variant takes these proven designs and modernises them with superior digital processing and robust electronic counter-countermeasures.
At the pinnacle of this radar family sits the Nebo-M complex, an integrated system that combines VHF, L-band, and X/S-band modules into one massive networked grid.
By combining the low-frequency detection power of systems like the Nebo-UM with the high-precision tracking of higher-frequency modules, this multi-band approach creates a virtually impenetrable surveillance net for modern air defence operations.
