The VA-111 Shkval torpedo is a Soviet-era invention that has revolutionized underwater warfare owing to its unprecedented speed reaching up to 200 knots.
This technological wonder, designed during the era of the Cold War, uses a rocket engine and the principle of supercavitation to generate this unimaginable velocity. Shkval vaporizes water at its nose tip, creating a gas bubble of reduced friction, with which it can move rapidly in water.
The Soviet Union depended on its submarine fleet to counter the supremacy of the United States Navy throughout the Cold War. The role of the United States Navy was not only to secure the flow of reinforcements that were supposed to be coming into Europe in case of a general war but also to direct the attack on the Soviet Union by hitting its ballistic missile submarines.
The USSR used a large number of diesel-electric submarines in the early phase but continued with more advanced nuclear attack submarines later on to make their chances better.
The Shkval torpedo became one of the most innovative underwater weapons devised by the Soviet Union. It was highly classified and almost unknown until the mid-1990s. Unlike traditional torpedoes that use propellers or pumpjets, Shkval uses a rocket engine.
This in itself is the reason for such a high speed, but drag in water made the problem of drag unique: to vaporize the water in front of the torpedo into gas.
By exhausting hot rocket exhaust out of its nose, Shkval boils the water ahead into steam creating a very thin gas bubble. This allows the torpedo to travel through gas experiencing much less drag and traveling at up to 200 knots.
This process is termed supercavitation, and to maintain it, the torpedo is obliged to stay inside the gas bubble, which makes the turnings difficult. Early versions of Shkval had rather primitive guidance systems, so the attack run was rather straight.
Designed in the 1960s as a quickly launched, antipodal strike weapon against NATO nuclear missile submarines, Shkval carried an atomic warhead and measured 533 mm in standard diameter with a 460-pound warhead. With a maximum range of 7,500 yards, Shkval entered mass production in 1978 and was then added to the Soviet Navy inventory in 1978.
Despite its benefits, Shkval has disadvantages. The noise generated by the gas bubble as well as the rocket engine indicates the general location of the launching submarine. The speed of the torpedo, meanwhile, may already overwhelm the enemy before it has even been given a chance to react.
Moreover, the noise also makes the use of traditional guidance systems inoperable since it is louder than the sonar systems of the torpedo. Shkval guidance systems were initially absent in early designs but instead relied on speed as opposed to accuracy. A later model compromises by using supercavitation to reach the target area before slowing down to search for its target.
The U.S. has been researching supercavitating torpedoes since 1997 but has yet to field a successful weapon. The U.S. Navy is continually improving the Mark 48 submarine torpedo, which demands greater capabilities than Shkval, including turning, identifying, and homing in on targets.
Presently, supercavitating torpedoes are fitted only on the Russian submarines, which are equipped with upgraded Shkval, carrying conventional warheads. Russia also sells its export version, the Shkval E, to other countries. Iran has also reportedly designed its supercavitating torpedo, called Hoot, allegedly as a reverse-engineered version of Shkval.
In 2004, the German defense contractor Diehl-BGT unveiled the Barracuda technology demonstrator torpedo traveling at 194 knots. The tests were designed to be launched from submarines as well as from surface ships. According to available reports, test models were said to be able to travel in straight courses as well as curved courses, but this program did not lead to the development of a marketable weapon.
The Shkval torpedo defies conventional undersea warfare. The 200-knot speed makes it an attractive capability, and in the context of increasing naval competition in the Atlantic and Pacific Oceans, more navies may adopt supercavitating designs, changing their undersea tactics. Undersea warfare is apt to become noisier and deadlier.