In a significant move to strengthen its airspace security, the Indian Air Force (IAF) is reportedly assessing the acquisition of the Russian S-500 "Prometheus" air defence system.
Defence sources indicate that India is looking to procure two squadrons of this advanced platform to complement its existing fleet of five S-400 "Triumph" batteries.
Officials clarified that this potential purchase is not intended to replace the S-400—which proved its combat worthiness during Operation Sindoor in May 2025—but rather to create a specialized, high-altitude shield capable of countering next-generation threats from China and Pakistan.
A Layered Defence Strategy
The IAF's interest in the S-500 comes as regional adversaries modernize their aerial fleets.While the S-400 remains a formidable system for engaging aircraft and cruise missiles up to 400 km, the S-500 is designed to dominate the upper atmosphere and near-space domains.
- The "Apex Predator": Entering service with Russian forces recently, the S-500 is engineered to work in tandem with the S-400. Its primary role is to intercept threats that operate at extreme speeds and altitudes, such as Intercontinental Ballistic Missiles (ICBMs) and hypersonic glide vehicles.
- Hypersonic Defence: The system is capable of neutralizing targets travelling at speeds exceeding Mach 5. Its specialized 77N6-N and 77N6-NH interceptors are designed to hit targets up to 600 km away and at altitudes reaching 200 km.
- Space Capability: This altitude ceiling allows the S-500 to engage threats before they re-enter the atmosphere, including satellites in low-earth orbit and fractional orbital bombardment systems.
Countering the Stealth Threat
A key driver behind this evaluation is the proliferation of stealth technology in the region.The IAF faces a dual threat from China’s operational J-20 "Mighty Dragon" fighters and the looming induction of the J-35A stealth aircraft by the Pakistan Air Force, potentially facilitated by Beijing.
The S-500 promises to degrade the advantage of these "invisible" aircraft through advanced sensor fusion:
- Multi-Band Detection: The system integrates a network of radars operating on different frequencies (VHF, L-band, and X-band).
- VHF Advantage: Long-wavelength VHF radars are generally effective at detecting the presence of stealth aircraft, which are typically shaped to deflect higher-frequency radar waves.
- The Kill Chain: While VHF radars can detect a stealth target (providing a "fuzzy" location), they lack the precision for missile guidance. The S-500’s network solves this by handing off the target to high-precision L-band or X-band radars for the final engagement.
Building on Combat Experience
The decision to pursue the S-500 appears deeply influenced by the lessons of Operation Sindoor.During the May 2025 conflict, India’s S-400 systems successfully neutralized high-value targets, including an AWACS (Airborne Warning and Control System) aircraft at a range of 314 km.
However, the conflict also highlighted the need for a "higher roof" to India's air defence architecture.
The S-500 would provide this by adding an exo-atmospheric layer (engaging targets outside the atmosphere) above the S-400's endo-atmospheric (inside the atmosphere) coverage.
Strategic Implications
The potential deal, estimated to be worth approximately ₹20,000 crore, faces geopolitical hurdles, particularly the risk of US sanctions under CAATSA (Countering America’s Adversaries Through Sanctions Act).However, discussions between New Delhi and Moscow have reportedly accelerated following recent regional tensions.
If concluded, this acquisition would integrate the S-500 into a comprehensive "kill web" alongside the S-400 and indigenous systems, potentially including future hypersonic cruise missiles like the BrahMos-II.
