The S-500 Prometheus is a focus of Russia’s effort to transform its air and missile defense policy. It’s marketed as a system that can defend against everything from cruise and ballistic missiles to hypersonic missiles and even satellites in low Earth orbit. For Moscow, it’s as much a symbol of technological aspiration as an answer to increasing Western military power.
On paper, the aims of the S-500 are impressive. It reportedly is capable of engaging targets as distant as 600 kilometers away and at altitudes of up to 200 kilometers, although more recent claims show slightly reduced capabilities.
It equips the 40N6M missile—already deployed with the S-400 and able to engage aircraft and cruise missiles at 400 kilometers—and newer 77N6 and 77N6-N1 missiles aimed at engaging ballistic missiles and satellites at greater distances. This combination of missiles is designed to provide the S-500 with the versatility to address a broad spectrum of current threats, a more and more important attribute on modern battlefields.
Development on the system commenced in earnest in approximately 2010, as massive state funding went into manufacturing facilities and integration under Russia’s State Armament Program. But the path to operationalization has been far from rosy. Despite President Vladimir Putin’s efforts in 2018 to order mass production, sanctions, supply chain failures, and shortages of trained labor held up advancement.
Engineers at manufacturer Almaz-Antey have reported ongoing issues with machinery and insufficient parts—particularly foreign-produced electronics—as significant obstacles. Whereas Russia has succeeded in upscaling production of missiles for older systems such as the S-400, the more advanced vehicles and radars required for the S-500 have encountered delays.
The initial system was eventually handed over in 2021 to the unit tasked with defending Moscow, but in a trimmed-down form. Most importantly, it lacked the interceptors for exoatmospheric targets—satellites and missiles beyond Earth’s atmosphere—so it could not yet realize its full potential. Since the Ukraine invasion, production has concentrated on systems that support combat operations directly, making projects such as the S-500 secondary.
Not everybody believes the S-500 is capable of meeting Russia’s lofty assertions. Analysts like the Center for European Policy Analysis’s Pavel Luzin believe that the system does not significantly outperform U.S. equivalents such as the THAAD missile defense system. They cite a lack of evidence that the 77N6 interceptors can consistently target objects beyond the atmosphere, along with ongoing issues in Russia’s internal electronics sector. Without superior quality parts, they contend, the S-500 will never live up to its ambitious design parameters.
Nonetheless, the Prometheus is a quantum leap forward from previous Russian defenses. A silo-based and nuclear-capable system that has protected Moscow since the Cold War, the older A-135 is unlike the new S-500. Carried on enormous 10×10 transporter-erector-launchers, it can be rapidly redeployed to new locations, improving survivability and expanding Russia’s anti-access and area denial (A2/AD) reach. It’s also intended to supplement—and later substitute for—the S-400, which has become a mainstay of both Russian and allied air defense. Nations like Turkey have already inquired about the system, demonstrating its potential as an export.
The S-500 has been featured in top-level tests, including the engagement of a ballistic missile target at Kapustin Yar range. Russian officials characterize it as having “no analogues” elsewhere in the world, with the ability to counter all known and emerging aerospace threats. But critics point out that decisive tests—such as the interception of hypersonic weapons under real-world conditions—remain to be proven.
Further down the road, Russia has also hinted at the S-550, a successor system designed to extend detection and engagement ranges even more. Officials say it will provide more advanced capabilities against hypersonic missiles and satellites, but so far, proof of its development is sparse.
The tale of the S-500 is really the tale of Russian defense modernization in general: grandiose plans, spectacular disappointments, and the incessant baggage of economic and technological constraints. Still, the mere presence of the system indicates Moscow’s resolve to maintain parity with changing threats and to demonstrate its capability to challenge the skies—regardless of whether the Prometheus truly proves worthy of its mythic designation.