Alfa-Class Submarine

The Alfa-class submarine (Project 705 Lira) was one of a series of 7 nuclear attack submarines in service with the Soviet Navy during the Cold War. With a streamlined hull entirely made of titanium, she was the fastest boat in the world, with a test depth of +400 m (1,300 feet). She was also characterized by stealth and her powerful sonar which could detect and track enemy vessels from a long distance. She featured a new type of sail design, which neatly blended into the hull to minimize water flow disturbance. All seven subs were assigned to the Soviet Navy's Northern Fleet, which operated through and from the Arctic Ocean, under the ice cap, secretly cruising into the Atlantic and Pacific Ocean.

The first Alfa-class submarine, K-64, was laid down on June 2, 1968. Being built on Sudomekh shipyards, in Leningrad (Saint Petersburg), she was launched on April 22, 1969, and commissioned on December 31, 1971. The last submarine of Project 705 Lira to be completed was K-463, which was commissioned in 1981; and the last boat of the series to be decommissioned was K-123, which was struck (phased out) on July 31, 1996; she had entered service with the Soviet Navy in 1977. They were all based on the Kola Peninsula, between the White Sea and the Barents Sea.

Like their American counterparts, the Project 705 submarines were never used in combat. However, they proved to be one of the most reliable Soviet subs of the Cold War period in terms of fire power and stealth. Not only did they represent a big shock and surprise to the US Government when they discovered their existence, but also a great threat to the US Navy's carriers. Only one of them, the K-64, had an initial technical problem with her first nuclear reactor, when the liquid metal in the primary coolant hardened. Thus, for safety reasons, she would be taken out of service in 1974, while the remaining six boats would keep sailing the seas flawlessly.

Technical Characteristics

Designed by Mikhail Rusanov, the Alfa-class submarine was a high-speed, nuclear-powered boat, which had been conceived to seek out and destroy NATO's submarines and aircraft carriers. She was powered by one BM-40A liquid-metal-cooled nuclear reactor, which generated 155 MW (megawatts). Using rods of uranium-235, it was a modular, two-section reactor, with two steam lines and circulating pumps. It produced pressurized steam to drive two turbines, which turned the generators. Submerged, she could move at the maximum speed of 41 knots, that is to say, 76 km/h (47 mph).

The hull of the Project 705 Lira submarine was of the double-hull design type. Both the inner and outer hull were made of titanium. This configuration and the material employed had already been used before to build the Project 627 (November-class) submarines. Titanium had the advantage of lowering the hull magnetic field, while the internal hull had an internal coating, which was designed to absorb own-ship machinery noise and reduce the acoustic signature of the submarine.

The Alfa-class submarine consisted of six compartments. Right above the control compartment, there was an escape chamber in the sail, which could accommodate the entire crew of 31 officers. In an emergency situation, the crew could enter the chamber through a hatch in the submarine. The chamber could be released and then float up to the surface through buoyancy and wait for rescue.

Specifications

Type: nuclear attack submarine

Displacement: 3,220 tons (submerged); 2,324 tons (surfaced)

Length: 81.4 m (267 feet)

Beam: 9.5 m (31 feet, 2 inches)

Draft: 7.1 m (23 feet, 3 inches)

Propulsion: one  BM-40A nuclear reactor, one 40,000-SHP steam turbine, and one shaft.

Maximum Speed: 41 knots (submerged); 12 knots (surfaced)

Range: sailing indefinitely for 20 years, but limited to 60 days for food and logistically supply.

Armament: six 533-mm torpedo tubes, with twenty VA-111 Shkval supercavitating torpedoes and eighteen 53-65K conventional torpedoes; 24 mines.

Below, an Alfa-class submarine on a naval base on the northern coast of Russia.

Five of the seven operational Project 705 Lira submarines moored at Zapadnaya, Litsa, naval base on the Kola Peninsula.

A Project 705 sub cruising on the surface in the northern Atlantic. You can notice how her sail blends into the hull. The masts could be retracted fully and covered over.

Below, an Alfa-class submarine photographed in the Barents Sea in the Summer of 1983. She had clean lines, revealing her underwater speed potential.

The Project 705 boat on dry dock for maintenance.