The single Mike class submarine was an unusual combination of experimental deep-diving platform and operational attack submarine. (US Navy)
Until the mid-1960s, the design of nuclear-powered attack submarines had been monopolised by the Malakhit bureau in Leningrad, which had produced the November, Victor and Alfa designs. However, in 1966 the Rubin bureau, which had hitherto produced only ballistic and cruise missile designs, successfully lobbied to design a new nuclear-powered attack submarine type. In August 1966, a staff requirement was issued for the Project 685 (NATO: Mike class) submarine, a large titanium-hulled boat that would have the hitherto unprecedented diving depth of 1,000m. This vessel would not just be an experimental deep-diving vessel, but would also be a fully armed combat submarine. Previous combat submarines had reached only 400m in depth, so the technical and design demands to achieve this would be considerable. The development work was protracted – it was eight years before the final design was approved (on 16 December 1974) and another four years before the boat, K278, was finally laid down.
The single Mike class submarine was an unusual combination of experimental deep-diving platform and operational attack submarine. (US Navy)
The titanium alloy hull, using alloy 48-T, reduced the weight of the submarine significantly, whilst the number of piercings of the outer hull were reduced to the minimum. For example, the forward torpedo loading hatch was removed and the torpedo tubes and scuppers were covered with special shield enclosures. As with the Alfa (Project 705) class, the boat’s conning tower incorporated an escape pod. The boat had six 533mm torpedo tubes with a total of 22 torpedoes (or equivalent weapons such as mines or torpedo-tube-launched anti-submarine missiles), and the full range of sonar, navigation and command systems expected of an operational combat submarine. The propulsion consisted of a single pressurised water reactor, propelling one screw, with two turbines and a small diesel generator, plus two emergency ‘creep’ motors that could be used in the event of a malfunction in the reactor. As with previous classes, high levels of automation were used to reduce the size of the crew. However, following initial trials the crew was raised to 64, and the previous crew of commissioned and warrant officers was supplemented by a number of junior ratings.
|
Project 685 |
|
|
Length/beam/draft (m) |
117.5/10.7/8 |
|
Displacement (tonnes) surfaced/underwater |
5,750/7,810 |
|
Maximum depth (m) |
1,000 |
|
Maximum speed (knots) surface/underwater |
14/30.6 knots |
|
Complement |
57, raised to 64 |
|
Armament |
6 533mm torpedo tubes, 22 torpedoes or equivalent |
|
Sonar |
Skat |
|
Radar |
Chibis |
|
Radio/electronic systems |
Bukhta, Medveditsa, Molinya-L, Omnibus |
|
Propulsion |
1xOK-650B-3 reactor |
|
Design bureau |
Rubin |
|
Chief designers |
N. A. Klimov/Yu. N. Kormilitsin |
Only one boat of the Mike class was built: K278 at the Severodvinsk yard. On completion, the boat spent a total of four years on a series of deep water and other trials. Although the Northern Fleet wished to have more vessels of this type, and the Rubin bureau lobbied for further construction, no more were authorised.
The forward part of the sail of the Komsomolets included an escape pod large enough to take the whole crew. (US Navy