Pr 633 'Nato Codename Romeo' Class

Design History

Project 633 began life as a 1954 TTZ for an advanced coastal submarine, essentially a development of Project 613 (Whiskey) exploiting the Kreislauf drive technology developed for Project 615. This version of Project 633 would have been fitted with Kreislauf diesels on both shafts. However, it quickly became apparent that Kreislauf technology was still too immature for fleet use so the design was revised to use the standard 37-D diesels. Since Project 613 had escaped the hull structural disaster that had blighted Project 611, no basic hull revisions were required and the modified Project 633 retained its original number.

The submarine was of double hull construction, the pressure hull being a mixture of internal and external framing. It was divided into seven compartments:

(a) forward torpedo room,

(b) living quarters and batteries,

(c) control room, living quarters and galley,

(d) diesels,

(e) electric motors and batteries and

(f) aft torpedo room and living quarters.

The machinery layout basically repeated that of Project 613 with a two-shaft powertrain with a single 2,000 shp 37-D diesel engine on each shaft to give a total of 4,000 shp. An archaic feature was that early members of this class, at least, retained strengthening for a gun before the bridge although no such weapon was ever mounted. This feature was perpetuated in Chinese-built Project 033 class submarines.

The new sonar outfit was a major advance on that installed in Project 613. It paralleled that being installed on the new Project 641 (Foxtrot) class oceangoing submarines and offered greatly improved target acquisition and localization capabilities. Derived from the WW2 German GHG/Balkon system and installed in a bow "onion", the MG-10 Feniks-M system offered a reasonable submarine detection capability. Directly above this was the MG-200 Arktika-M active scanning sonar that supplied target data to the new Leningrad fire control system. Leningrad was a copy of the US WW2 TDC system and was the first real fire control equipment fitted to Russian submarines. It would remain a standard fit for nearly 20 years. A sonar intercept system, the MG-23 Svet-M was installed in the sail structure. Finally, a small underwater telephone was installed on top of the MG-200 set to give the bow "rhino horn" characteristic of this class.

Up to 560 submarines of the new Project 633 design were projected but the program was abruptly terminated long before this number was reached. In 1955, Khruschev decided that all non-nuclear submarine construction would be terminated. The Soviet Navy staff fought this proposal, suggesting that nuclear submarines would be too expensive to build in the numbers required and diesel-electrics were, in any case, required for shallow water and coastal work. This temporarily saved both Project 641 and Project 633 but at cost of essentially merging their roles. It was impossible to justify building both types and, in 1959, construction of further Project 633 class boats was cancelled. The production tooling and blueprints were provided to China which put the type into mass production as Project 033.

The basic Project 633 attack submarine was also used in a series of missile designs that did not see production. One, Project 633A, was proposed in response to a 1955 TTZ for a submarine equipped to fire the new P-15 Termit anti-ship missile. Four such missiles would have been carried in external cylinder launchers faired into the outer hull casing, one pair before the sail, the other aft of it. Although the Soviet Navy did not build any submarines of this type, the plans were transferred to China with the rest of the Project 633 blueprints. The Chinese subsequently built a single submarine using a modified version of these plans, the Project 033G Wuhan.

Another missile submarine, Project 633B was intended to carry the P-5 Pityorka (Shaddock) strategic cruise missile. Again, four missiles would have been carried in a grossly enlarged semi-streamlined superstructure. As with Project 633 and Project 633A, Project 633B was cancelled along with the rest of the Project 633 program but the redesigned superstructure was used in a missile conversion of Project 613 class boats, the Project 665 Whiskey Longbin.