Find a Security Clearance Job!


Project 705 Lira
Alfa class
Attack Submarine (Nuclear Powered)

The Project 705 Alfa class constitued the world's fastest and deepest diving submarines of their time. The submarine featured a high power-to-weight reactor to increase the power-to-weight and volume ratios of her propulsion plant, the first use of titanium for the hull, extensive automation, and advanced drag-reduction configuration.

Project 705 originated in a 1957 requirement for a 1500 ton "interceptor" submarine capable of a speed of 40 knots that would sortie to attack American aircraft carriers. Using a titanium alloy allowed the thickness and weight of the hull to be reduced, producing a remarkably small, very fast submarine. Around 1963 the design was substantially revised, with the displacement increased to 2,300 tons, the number of internal compartments increased from three to six and the size of the crew was doubled.

Construction of the first Project 661 prototype unit began around 1965, and was completed at the Sudomekh shipyard in Leningrad in 1972. The prototype was rebuilt after trials, and subsequently broken up around 1974. Made from titanium alloys, it could accelerate to a speed of 44.7 knots, a record which will hardly be beaten in the near future.

Although a much-feared design in the West, these concerns were prompted by grossly exaggerated accounts of the boat's capabilities and an assumption that they represented the main thrust of Soviet submarine development. The fast, deep diving nuclear submarine threat proved a false alarm, but they provoked massive investments in ASW weapons by the US Navy, and resulting in dramatic improvements in the Mk. 46 and Mk. 48 torpedoes that apparently culminated in the 63-knot ADCAP torpedo.

Extremely noisy at high speeds, the noise levels of the Alfa at lower speeds were generally similar to that of other Soviet SSNs. Though extremely fast, the boats were unreliable, poorly armed and with sensors that were unique, hard to maintain and frequently defective. Two different models of liquid metal (probably lead-bismuth) reactors were used. The four boats built at the Admiralty shipyard used the BM-40A reactor with two separate steam loops and circulating pumps. The boats built at Severodvinsk [Project 705K] used the OK-550 with branched first-loop lines and triple circulating loops and pumps.

The reactors required a heater to prevent the liquid metal coolant from solidifying. In 1972 the reactor on K-377 suffered a casualty during sea trials and the metal coolant "froze" destroying the reactor. In 1982 the reactor on K.316 was destroyed when the heating system was accidentally turned off. A special facility was constructed the submarines were moored to supply superheated steam to heat the liquid metal when the reactors were shut down. External heating proved unsatisfactory, and the reactors had to be kept running even while the submarines were in port.

Series production of the Project 705 boats began in the mid-1970s, and the program ended in 1983 with the sixth production unit. Eventually four of the seven Project 705s were lost due to reactor failures. One boat was retired by the end of 1987, and four others were decommissioned in 1990-1992. At least one [and possibly two] was modified with VM-4 pressurized water reactors from Project 671B and used for test activities prior to being decommissioned in 1995.

Lira - Lyrefish

A lyrefish is a gurnard, Trigla lyra, of the family Triglidæ, found in the Mediterranean and on the coasts of England and France.The gurnard fish, which are marine, all afford excellent food. They have a scaly body, of a uniform shape, compressed laterally, and attenuated towards the tail. The head is broader than the body, and slopes towards the snout, where it is armed.with spines ; the upper jaw is divided, and extends beyond the lower. The eyes are near the top of the head, large and prominent, particularly the upper margin of the orbits. The dorsal fins are unequal, the first short, high and acideate \ the second long, sloping and radiate. The ventral and pectoral are unconunonly large, and from their base hang three loose and slender appendages. Many of the species utter a peculiar noise when taken ; many of the species are provided with pectoral fins, sufficiently large to enable them to spring out of the water. One of the species has been denominated the lyre fish, on account of its bifurcated rostrum, which bears a faint resemblance to that instrument. "As mute as a fish" has come to be proverbial, nevertheless there are many fishes which can and do utter sounds more or less musical. The gurnards, one of which is known as the lyre-fish, emit a grunting sound when being taken out of the water-due, it is said, to the escape of gas from the air-bladder.

Join the mailing list