IAF Tactics to Reduce S-400 Vulnerability

AI graphic showing an IAF S-400 launcher evading counter battery fire

It's been widely reported that the IAF has reduced the vulnerability of its S-400 systems by launching missiles on the move. 

It's important to put the IAF achievement in the correct perspective.

The S-400 system is a mobile system but does not have launch on the move capability like short-range SAMs such as the Pantsir-S1 or Tor (which are explicitly designed for firing on the move).

The S-400 is a  mobile (up to 60 km/h on roads, 25 km/h off-road) system that can reach "ready to fire" status in as little as 5 minutes from a marching column without full redeployment (rapid-reaction), or 10–15 minutes in full development mode where the entire battery or regiment properly positions into its battle formation.

In firing position, the TEL deploys hydraulic stabilizer jacks (typically two on each side of the trailer/chassis) to level and steady the vehicle. 

IAF's New S-400 Operatoions Tactics

Using the IAF's newly developed tactics, a S-400 battery prepares for launch while still moving at low speeds (~5–7 km/h). When ready to launch, it stops, stabilizes, fires quickly, retracts its stabilizing pads and speeds away (scoots).

With the launcher continuously moving, AWACS or satellite based reconnaissance cannot provide counter battery missile systems the exact coordinates of the S-400 component systems.  

During Op Sindoor, IAF batteries reportedly evaded counter battery fire by quickly relocating. 

The IAF new tactics are more advanced and make counter battery fire very challenging for the adversary. 

The IAF tactics requires training and situational awareness - satellite pass schedule and airborne ISR assets positioning. It possibly also relies on surveyed and flattened terrain to launch with lower levels of stabilization. 

It's conceivable that the launch tubes are raised to a vertical position while on the move and then the platform is lightly stabilized for immediate launch. 

It's unlikely that the IAF has made any hardware modification to the equipment though software tweaks cannot be ruled out.

Copyright © Vijainder K Thakur. First published on Thumkar.

Russia Moves to End Reliance on Chinese Chips for Su-57 and S-400 Systems

Gemini Generated Image

Microwave microchips for the Su-57 fighter and S-500 Prometheus air-defence systems are expected to be manufactured within Russia by the end of 2027.

The governor of Sverdlovsk Oblast, Denis Pasler, recently announced that an enterprise has begun designing and constructing the country’s first factory capable of serial production of microwave microchips across the full technological cycle.

According to Pasler, the planned production capacity of the facility will be up to 2,000 silicon wafers per year.

Microwave microchips are integrated circuits (ICs) designed to operate at microwave frequencies, ranging from roughly 300 MHz to 300 GHz. They are used in applications such as radar, satellite communications, unmanned systems, wireless networks, and high-speed data processing.

A common example is the Monolithic Microwave Integrated Circuit (MMIC), which integrates components such as transistors, resistors, and capacitors onto a single semiconductor substrate—typically gallium arsenide (GaAs) or silicon—to process microwave signals efficiently.

These chips handle ultrafast data and wireless signals in real time for tasks including signal decoding, radar tracking, and pattern recognition.

The Su-57’s N036 Byelka airborne radar is likely to rely on such microwave chips, as do the 96L6-CP radar of the S-350A Vityaz air-defence system and the 98L6 Yenisei radar used with the S-500 and S-400 systems.

Su-57 Byelka Radar

The N036 Byelka (“Squirrel”) is an advanced X-band Active Electronically Scanned Array (AESA) radar system developed by the Tikhomirov Scientific Research Institute of Instrument Design (NIIP) for the fifth-generation Sukhoi Su-57 fighter.

It serves as the aircraft’s primary fire-control radar, featuring a nose-mounted N036-1-01 array with approximately 1,514–1,526 gallium arsenide (GaAs) transmit/receive (T/R) modules. This is supplemented by two side-looking N036B-1-01 X-band arrays, each with around 358–404 T/R modules, providing an expanded azimuth coverage of up to ±135°. In addition, L-band arrays embedded in the wing leading edges support IFF and electronic-warfare functions.

The GaAs substrate offers high electron mobility, low noise, and efficient operation in dense electronic environments, although it lags behind gallium nitride (GaN) in power density and heat dissipation.

Key capabilities reportedly include detection ranges of up to 400 km against targets with a 1 m² radar cross-section, simultaneous tracking of 60 airborne and 30 ground targets, and engagement of up to 16 air and four surface targets. Air-to-air and air-to-ground modes can operate concurrently.

The system incorporates sensor fusion and additional rear-facing elements to provide near-360° coverage, enhancing situational awareness, resistance to jamming, and survivability in contested airspace.

S-400 / S-500 Yenisei Radar

The Yenisei radar is an advanced S-band AESA system developed primarily for the S-500 Prometey air-defence system.

It features a large AESA array—approximately 3 × 4 metres—based on gallium arsenide technology. The radar offers long detection ranges of up to 600 km, high resolution, precise tracking of both ballistic and aerodynamic targets, and strong resistance to electronic countermeasures.

Designed for continuous, long-duration operation, it also incorporates low-probability-of-intercept characteristics.

Although developed for the S-500, the Yenisei can be integrated with S-400 batteries as a multifunctional fire-control radar, improving missile guidance accuracy and overall system effectiveness in dense electronic-warfare environments.

Russia's Dependence on China

There is speculation that Russia is dependent on China for microchips and MMICs fitted on its high end systems. While there is likelihood that the speculation reflects reality, it is important to note that Russia produces MMICs domestically through firms like Mikropribor and Istok. However, the MMIC production has relied on imported components and machinery. It's possible that MMIC production was disrupted after the imposition of Western sanctions in 2022 limiting Russia's access to advanced semiconductors. 

It is likely that now at least some MMICs in the Su-57's N036 Byelka radar and S-400's associated radars (such as the 92N6E Grave Stone or integrable Yenisei) are sourced from or via China.

The evidence for this is circumstantial. For example, in 2023-2024, China supplied ~90% of Russia's microelectronics, including specialized chips for guidance, radar, and military applications.

However, since production at Mikropribor pivots around components sourced from the West, it is likely that China is being used primarily as a conduit for importing Western components that go into MMICs. 

For example, the S-400 system depends on foreign radar substrates (e.g., US-made RO4003C laminates) obtained via China/Hong Kong. 

Because of China's limited holding of S-400 system, it is unlikely that they are locally manufacturing major electronic components that go into the system. As such, China likely supplies to Russia other electronic material such as PCB laminates. 

It's important to note that the governor of Sverdlovsk Oblast, Denis Pasler announced that the new plant would be the "country’s first factory capable of serial production of microwave microchips across the full technological cycle."

Impact on India

India, which currently operates three S-400 systems, is likely to acquire at least ten eventually. Local manufacture of S-400 systems is also being considered.

Meanwhile, HAL is in advanced technical negotiations with Russia’s UAC for the local manufacture of the Su-57 stealth fighter.

Based on the analysis above, it is highly unlikely that IAF S-400 or Su-57 systems would be negatively impacted by Russia’s likely limited and transient dependence on Chinese electronic components.

Russia’s investment in full-cycle design and development of MMICs will ensure that India does not become dependent on China.

In addition, India already has design capabilities and ambitious plans to manufacture MMICs as part of its broader semiconductor push under the India Semiconductor Mission (ISM). Indian design plans reportedly include advanced 3 nm nodes.

MMIC manufacturing capability is also emerging through plans that include a US–India joint fab for GaN and SiC semiconductors by 2029.

Within a reasonable timeframe, India would be in a position to manufacture the electronic components required for the S-400 and Su-57 systems.

Copyright © Vijainder K Thakur. First published on Thumkar.

Is DRDO Overprojecting Project Kusha to Undercut Local S-400 Manufacturing?

Conceptual view of a deployed Kusha system

The Indian mainstream media, ever inclined to hype and sensationalise defence-related news, is at it again. This time, the focus is on Project Kusha.

Media professionals, lacking deep enough insight into weapon systems, are hyping DRDO claims about the capabilities of Project Kusha and its projected development timelines, instead of critically questioning the claims.

Let us first understand what Project Kusha is and then see for ourselves whether DRDO claims are realistic.

Project Kusha: Conceptual Overview

Based on statements by DRDO officials, Project Kusha is an Integrated Air Defence System (IADS) that is conceptually similar to the Russian S-300, S-350, S-400 and S-500 systems.

An IADS provides layered (short, medium- and long-range) defence against a wide spectrum of aerial threats, ranging from medium-sized drones and helicopters to cruise missiles, fighters, aerial force multipliers such as tankers, AWACS and ISR platforms, as well as short- and medium-range ballistic missiles.

Russia is the only country in the world that has so far developed full-spectrum IADS. The Indian Air Force (IAF) is in the process of procuring the S-400 system from Russia. The three systems already acquired proved very effective during Operation Sindoor. The S-400’s track record during the ongoing war in Ukraine has also been impressive.

Understandably, the Indian defence media was elated when DRDO announced in 2025 that it would be developing an IADS. The media went overboard, projecting Kusha not just as an S-400 analogue but as an S-500 analogue. The former claim was a stretch; the latter, a joke. 

A major difference between the S-400 and the S-500 is that the latter is capable of engaging hypersonic aerial threats. India will first need to operationally deploy a hypersonic manoeuvring missile before it can develop an interceptor for such a missile. At this point in time, we are well short of that capability.

Emboldened by the puerility of media questioning, DRDO officials have put forward extraordinarily ambitious timelines for Project Kusha—timelines that bear little resemblance to past performance.

Kusha capabilities

As noted earlier, Kusha is an integrated air defence system, broadly comparable to the S-400, and is designed to employ a layered mix of short-, medium- and long-range interceptor missiles.

The single-stage short-range Kusha interceptor, designated Mk-1 and having a range of approximately 50–60 km, forms the core of all three missile variants.

The medium-range (Kusha Mk-2) and long-range (Kusha Mk-3) variants build upon this core interceptor by adding a booster stage, making them two-stage interceptors. The two variants differ primarily in the diameter of the booster stage.

Development Progress

At this point in time, the Kusha IADS exists only as a concept, and the Kusha Mk-1 most likely as a designed and wind-tunnel-tested model.

According to an HT report, the first development trials of Kusha Mk-1 are expected to take place in September this year. DRDO expects the Kusha Mk-1 to be inducted as a standalone short-range missile system by 2028.

Development trials of both Kusha Mk-2 and Kusha Mk-3 are projected to start in 2027.

In other words, the three missiles will be developed on parallel tracks after the Mk-1 interceptor has demonstrated the efficacy of its design.

Based on the HT report, DRDO appears to be projecting that by 2030, Kusha will be ready as an IADS with three different interceptor missiles covering ranges from 50 to 400 km.

This projection is certainly not backed by DRDO’s past record in operationalising indigenously developed air defence missile systems, nor does it have a global precedent. The claim is so divergent from reality that it can only be explained as an attempt to scuttle the local manufacture of S-400 system components.

DRDO has done well with recent missile projects such as Akash Prime and Akash NG, but nowhere near well enough to enable it to develop the Kusha system within five years. 

Akash Prime

Akash Prime is an incremental upgrade of the Akash missile in which an active seeker replaces the passive seeker of the Akash. Other improvements include a mobile launcher and more reliable performance under low temperature environments at higher altitudes. The missile reportedly has a longer engagement range of 40-km

The maiden test of the Akash Prime missile was done on September 27, 2021. During the test the missile successfully intercepted and destroyed an unmanned aerial target. Five years since its maiden test,  the missile has yet to be operationally inducted.

Akash NG

Akash NG was first mooted in 2010. The DRDO had then projected a development time of just 18 months. Notably, the claim notwithstanding, the DRDO was yet to develop a RF seeker for any missile at that point of time. 

The project was sanctioned in September 2016 after DRDO acquired RF seeker technology with help from Russia. 

The missile was first tested on January 25, 2021, using an electronic target to validate its ability to engage a hard manoeuvring target.

The missile was tested for the second time on July 21, 2021, once again without its active seeker, against an electronic target. Subsequent phased testing progressively demonstrated all design capabilities of the missile.

Following flight testing on December 24, 2024 DRDO announced that the missile system had “successfully intercepted aerial targets at different ranges and altitudes, including near-boundary low-altitude and long-range, high-altitude scenarios.”

The test marked the successful completion of User Evaluation Trials of the missile, meeting all PSQR requirements. However, till today, the missile is yet to be inducted into operational service. 

In an earlier blog post, I had praised DRDO's development of a new clean sheet, dual pulse motor missile with an active seeker and a very capable radar in just around 10 years. 

Conclusion

The IAF needs a proven IADS now, not in the future. This was shockingly evident during Operation Sindoor. One only needs to close one’s eyes and relive the operation hour by hour, day by day, to realise how badly we could have been mauled had the IAF not operationally deployed its S-400 regiments.

DRDO’s projections that it will be able to develop three different variants of Kusha interceptor missiles within the next four to five years are overly optimistic at best.

Possibly, this is a disingenuous attempt to prevent the IAF from taking up local manufacture of the S-400 system.

From DRDO’s point of view, local manufacture of the S-400 or S-500 system would dramatically reduce the market size for its Kusha system, as and when it is fully developed.

However, DRDO needs to tread with caution. In the past, capability overprojections have resulted in a precipitous drop in IAF squadron strength. As a result of this decline, the IAF is now more heavily reliant on air defence than it has ever been in the past.

While there can be no doubt that the IAF should look at domestic options despite limited capability shortfalls, there can also be no doubt that such compromises should not enfeeble the IAF to an extent where it loses its deterrent capability. DRDO must keep the national interest in mind to the same extent that it expects the IAF to do so.

Overstating its capabilities and projecting unrealistic timelines to secure the only market segment it is capable of competing in is not the right approach.

Copyright © Vijainder K Thakur. First published on Thumkar.