In underwater battles, speed is not a luxury—it’s a necessity. And now, due to the development of supercavitating torpedoes, the very dynamics of naval warfare is undergoing a revolution. Imagine a weapon that does not swim in the water as a conventional torpedo does, but rather hovers within a pocket of gas, tearing through the sea at scorching velocities that conventional technology can simply not compete with. This is the reality of supercavitation, and it’s converting the oceans into arenas where decisions have to be made in seconds, and aged dogma no longer means dominance.
But how does supercavitation work? Simply put, the torpedo creates a bubble of gas around itself, dramatically reducing the resistance of water. Where a typical torpedo would max out at 50 knots, a supercavitating torpedo such as Russia’s VA-111 Shkval can allegedly exceed 200 knots. That’s quick enough to render interception virtually impossible with existing systems. It does this with a specially designed nose cone and onboard gas generators, which collectively form that all-important gas cavity. But with all speed is complexity—operating a weapon that’s essentially “flying” underwater is no cakewalk, and the rocket propulsion it uses is loud, consumes fuel rapidly, and has limited range.
Russia was the first to do this, having introduced the Shkval into service in the late 1970s. Then, too, it was a technological wonder: a rocket-boosted torpedo that could cut the distance to the target in a matter of minutes. Its only disadvantage, however, was its primitive guidance system—it could only effectively go in a straight line.
But progress never stops. Russian officials have signaled that improvements to the Shkval’s guidance system might double its range and pave the way for more sophisticated variants, even nuclear-tipped ones. As one Russian engineer described it, upgrading the guidance system would fundamentally change the way the weapon is employed, bringing it from a blunt-force solution to a precision threat.
Iran has also jumped into the fray with its variant, the Hoot torpedo. According to the Shkval’s design, the Hoot is a good fit with Iran’s asymmetric naval strategy, especially in bottlenecks such as the Strait of Hormuz. While its range is relatively short, only about 10 to 15 kilometers, its speed makes it very difficult to counter.
With the capability to fire from a range of platforms, from submarines and small boats to coastal launchers, Iran introduced an element of uncertainty into any future naval conflict. As one defense commentator put it, the U.S. now has neither an equivalent weapon nor a method certain to halt one, and nations such as Iran have a niche advantage here.
China, never behind the times in innovative defense technology, is investing heavily in developing supercavitating systems. Recent reports indicate successes based on AI-guidance, allowing torpedoes to differentiate between actual targets and decoys with high accuracy, more than 90 percent, some reports assert.
Coupled with technological advancements such as liquid-membrane technology to simplify launch issues, China seems to be homing in on overcoming fuel efficiency and maneuverability issues that have plagued torpedoes for so long. If successful, such advances might open the door to even more revolutionary breakthroughs, like supercavitating submarines running at supersonic speeds, once considered mere science fiction.
The United States has been looking into the possibility, too, in particular through DARPA’s Underwater Express program. Although building a wholly supercavitating submarine has been an enormous challenge, the investigation has brought with it promising spin-off developments like supercavitating projectiles and demonstration boats like the Ghost, which employs a partially supercavitating hull to cut drag. In the meantime, Germany’s Barracuda system presents another approach to the challenge, with speed added to improved homing capability for a possible high-speed intercept of other threats.
Strategically speaking, these supercavitating torpedoes level the playing field. Their greatest asset isn’t speed—it’s that they warp time. Launched, they leave enemy ships just seconds to react. That makes them perfect for surprise raids, particularly when launched from difficult-to-detect systems such as unmanned underwater craft or beach batteries. For minor navies or nations with little fleet to speak of, supercavitating weapons present a unique chance to get on even terms, if only for an instant.
Yet, this technology is not without its flaws. The gas bubble that propels the torpedo at high speed also restricts its maneuverability, as conventional control surfaces are not effective within it. The fuel requirements are extreme, and the noise produced by the rocket engine is a giveaway to anyone within earshot underwater. Engineers are trying workarounds—vectored thrust, electromagnetic guidance, and AI-augmented navigation—but these are all in the experimental stages and have challenges of their own.
In the future, the biggest wild card is artificial intelligence. More intelligent onboard systems would render these torpedoes increasingly independent and self-correcting in mid-course, and future designs might even cooperate as coordinated swarms. That type of swarm warfare would add an entirely new dimension to undersea conflict, making defense even more challenging. Whatever happens, one thing is certain: the era of the lumbering, slow-moving torpedo is passing into history. It will be replaced by a new generation of high-speed, stop-at-nothing weapons that have the potential to redefine maritime strategy for years, if not decades, to come.