More on the LOSHARIK DeepDiving Russian Research Nuclear Submarine An Obvious Mission
By Bruce Rule - Jul 30, 2015
A Russian website states that the Admiralteiskiye Shipyards, St Petersburg builds “deep submersibles capable of diving (to) 6000 meters (19,700 feet)." This is an indirect reference to the LOSHARIK Class Russian nuclear-powered research submarine and further supports the exceptional depth capability of that platform.
To save those interested the trouble of researching this site, see below a copy of the writer's 5 May 15 summary posting on the LOSHARIK, one function of which almost certainly involves the ispection of western sea-floor acoustic sensors (IUSS assets) located in very deep water (but bet this cannot be done without the operation being detected by those sensors being "inspected.").
Final Assessment of the LOSHARIK Special Purpose Nuclear Submarine: Very Deep, Very Slow and Noisy
When you compare the MIKE Class Soviet nuclear submarine – which had a conventional pressure hull design but was constructed of titanium that provided a never-exceed depth of 4100-feet – with the LOSHARIK – which has seven 18-foot external diameter titanium spheres, the first five of which are interconnected by very short, narrow diameter, crawl-through tunnels, it is evident the LOSHARIK was designed to be a very deep-diving platform because spheres are more pressure-resistant than larger diameter cylinders. Thus, open source references to a 20,000 foot capability should be seriously considered. As previously discussed, the LOSHARIK is transported to and from areas of intended operations attached to a highly modified DELTA IV, hence, there is no requirement for a propulsion capability that can provide reasonable transit speeds of 8-10 knots. Further, the hull (sphere) penetrations required to accommodate the larger diameter propulsion shaft required for moderate speeds are to be avoided in a very deep-diving platform. Best to limit such penetrations to a very small diameter propulsion shaft, hydraulic lines and power cables. In that regard, note that the two aft-most spheres – which contain the propulsion system and the reactor are not connected with those forward spheres; hence, any leak through a shaft seal in the seventh sphere would be isolated from the crew, sensor systems and control spaces. Since less than 100 horsepower would be required to propel the LOSHARIK at the four knot speed required for DELTA IV supported operations, it is assessed that value represents the maximum platform speed. As previously discussed, space available within the LOSHARIK reactor and propulsion spheres probably cannot accommodate the installation of effective noise-reduction technology such as raft systems to isolate rotating machinery. So, the best assessment from open sources indicates LOSHARIK is very deep-diving, very slow and is not quiet, especially when employing hydraulically-actuated manipulators. Advantages: long duration missions at extreme depths and the ability to observe/recover material from the bottom.