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Or maybe one should call it a baby YASEN class submarine.
http://nationalinterest.org/blog/the...oday-its-21001
http://nationalinterest.org/blog/the...oday-its-21001
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These article continue to cite old and disproven performance figures for the Alfa class. Norman Polmar spent considerable time in Russia and met with several designers at the Malachite Design bureau, which was the Project 705 Lira (NATO: Alfa) source. The Alfa was made of titanium to lower the hull weight by reducing hull metal thickness, thereby increasing the reserve buoyancy of the relatively small submarine. The diving depth of the Alfas was roughly equivalent to contemporary Permit and Sturgeon classes, 400 meters (1300 feet). The original estimates of 640 meters (2100 ft) were much too deep. The Alfas were capable of high speed (around 40 kts.), which resulted in high flow noise at those speeds, increasing acoustic detection depth. The contemporary Papa class (Project 661) could go about 42-44 kts., and the flow noise was so great internally that even shouting in the forward torpedo room could not be understood. Similar problems would arise in the Alfas, as noise increase is not a linear function of speed but rises asymptotocally at high speed; so does the engine power needed to reach high speed.
Finally with the same number of Alfas built, the liquid metal lead bismuth reactors proved to be very difficult to handle. Two slightly different lead-bismuth reactors were used in the 705s, the modular OK-550 and the two section BM-40A. The lead Alfa submarine leaked two tons of the primary lead bismuth coolant and the K-64 had the liquid metal freeze (solidify) in the reactor, which ended up scrapping that hull. The entire primary cooling loop had to kept at temperatures above where the lead-bismuth solidified. The Alfas tried to push the envelope in submarine innovation, but in the end, the few members of the class had significant engineering issues.Comment
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