Alfa: Russia's Cold War Submarine Wonder Weapon That NATO Feared
The Soviet Union began the Cold War well behind the United States in submarine technology. Although the Soviets acquired several of the most advanced German submarine types towards the end of the war, the United States had amassed a wealth of experience in submarine and antisubmarine practice from the Pacific War and the Battle of the Atlantic. Combined with other technological advantages, the United States leapt out to a significant lead in submarine tech (especially nuclear submarines) in the first two decades of the Cold War.
In particular, early Soviet nuclear submarines struggled to compete with the West in stealth and reliability. After the first few designs came to fruition, the Soviets decided to undertake a combination of brute force and extremely risky high technology. The brute-force part meant building a submarine that could move faster and dive deeper than any Western counterpart; the high-tech part meant innovative hull design, reactor design and material manipulation. The result was the Type 705 Lyra (known as Alfa in NATO), a submarine that the West regarded as a profound, if short-lived, threat to its undersea dominance.
With the Lyra class, the Soviets sought to accomplish two goals. First, they wanted to produce a weapon capable of changing the character of naval warfare in the North Atlantic and the Arctic, a weapon that could threaten the overwhelming surface advantages of the NATO navies. Unlike their Western counterparts, which preferred multirole platforms, the Soviets were fine submarines dedicated to a single mission: the high-speed “interception” of NATO surface squadrons, especially carrier battle groups. Second, they wanted to jumpstart technological development, producing innovations that future submarines would incorporate, if only in piecemeal fashion. An incidental third goal was to force NATO navies to spend money and time adapting to the threat that the Lyras would present.
The Lyra class certainly met the second criterion. Following an interim design (the K-162 “Papa”-class cruise-missile submarine), the Lyras had a titanium hull in order to produce tolerances necessary for high speed and for extreme deep diving. To keep the size of the crew small, the Lyra class employed advanced techniques for automating key systems, a decision which also enhanced the combat reaction speed of the crew, although it made at-sea repairs and maintenance extremely difficult.
To achieve high speed, the Alfas used a remarkably innovative lead-cooled fast reactor design. This allowed a tremendous amount of power in a compact space. However, it also created staggering maintenance problems, few of which could be resolved by the small crew at sea. Indeed, even in port the Soviet Navy struggled to keep the Alfas in service.
The Lyras could put up numbers that no class of submarine has matched (apart from the “Papa” SSGN) before or since. Submerged, they could travel at forty-one knots (and could reach that speed with a startling degree of acceleration). They could dive to at least 2,200 feet, far deeper than any NATO submarine of the time, or today.
The speed and diving depth of the Alfa allowed it to evade most contemporary NATO torpedoes, although in combat this would also have made it difficult for the Alfa to move into attack position. Also because of their small size, the Alfas carried a weapons arsenal smaller than most other Soviet boats—a mix of eighteen to twenty-one torpedoes and cruise missiles. Nevertheless, this arsenal could wreak havoc on a NATO group without the means to effectively respond.
The Alfas were not particularly quiet, especially when they approached at high speed. However, their ability to dive deep gave them some stealth capabilities, depending on oceanic conditions. More importantly, they could outrun and outdive most existing NATO weapons, making them very difficult to catch and kill.
As with the MiG-25 and other Soviet “super-weapons,” NATO took the threat of the Alfa very seriously. Extant torpedoes and other antisubmarine weapons would struggle to catch the Alfas, or to dive deep enough to destroy them. Whether out of genuine panic, or out of the desire to use the threat of the Alfas to spur innovation and funding, the U.S. Navy and the Royal Navy embarked on crash programs to develop sensors that could detect the Alfas, and weapons that could kill them.
This effort resulted in a few weapons, including the Mark 48 ADCAP torpedo, which can reputedly travel at sixty-three knots. The Royal Navy developed a similar torpedo, dubbed “Spearfish.” The United States also pursued the “Sea Lance” supersonic missile system, designed to deliver a torpedo or nuclear depth charge at ranges of up to one hundred miles. The United States cancelled the Sea Lance program at the end of the Cold War, roughly at the same time that the Lyra class left service.