BACKGROUND
Quote from the linked site (http://www.pdmz.ru/en/doc-2.html) After the Great Patriotic War (WWII), the Soviet state faced the task - as soon as possible to reverse its effects: to restore the national economy, to strengthen the Soviet Army and Navy. That is why on Nov. 8, 1948 The Council of Ministers adopted a decree number 4176-1673ss on construction in the city of Penza, machine-building factory to produce the main types of marine diesel engines 30D, 33D and 37D with a capacity of 2,000 horsepower for submarines, sea hunters and other ships of the Military Navy. (end quote)
In the mid-1960s, after installing two stroke/cycle 37Ds in numerous WHISKEY (236), ZULU (28), ROMEO (133), FOXTROT (about 40) and GOLF Class submarines (23), that engine was replaced in new-construction FOXTROTs and TANGOs with the old (pre-WWII) four-stroke/cycle Kolomna 30/38 1D42 engine connected to its propeller shaft through a single-stage gear system that reduced the maximum engine speed of 715 rpm to a shaft speed of 500 rpm. That basic engine block – with many designations (1DL42, 2D42,2D42M and 1D43) was also used in JULIETT, INDIA and BRAVO Class submarines, and as main propulsion diesel-generators in all KILO units.
PROBLEMS BEFORE AND AFTER THE ENGINE SWITCH
As previously discussed, FOXTROT B-130 experienced the failure of all three two stroke/cycle Kolomna 37D engines while deployed to WESTLANT during the Cuban Missile Crisis period in Oct 1962. A Soviet source acknowledged this to be the result of a “factory defect.”
In March 1968, while conducting a PAC missile patrol, a ZULU (B-62), had all three 37D engines fail. An AR (submarine rescue) and an Oiler were sent to assist. Repair efforts were not effective. The surface ships remained to support the ZULU for over a month, eventually towing it back to Petropavlovsk.
Note: when a GOLF Class SSB was extensively modified to provide a test platform for the SS-N-8 missile, the 37Ds were replaced with 2D42 engines even though that modified GOLF III would never deploy beyond Northern Fleet home waters.
COMMENT
So, while the Soviet use of “continental” engine types (four stroke/cycle) was still being taught behind the Green Door at the Fleet Sonar School, Key West (late 1961 or early 1962), the Soviets, after completing 460 submarines with two stroke/cycle 37Ds, had decided to switch to the four stroke/cycle D42 series engine. Talk about being out of synch and in the Dark Ages!! And the writer as one of those who peddled that misinformation at the FSS.
The Soviets may not have liked the 37D but I sure enjoyed them a few times :). D/E at 500 rpm, hell yeah!
While we're on the subject of propulsion, I'm gonna ask a question of which the answer may be known by most but not by me.
The T/E mode of the HENs (Same generation as the original 37Ds) was also a signature that we all had "fun" with. My question is to Bruce "Was that signature purely a result of sloppy engineering or was there a point to that instability"?
John
John:
Sorry for the delay in responding to your excellent question which I never knew to have been previously asked. (Just got back from four days getting poked in a local hospital.)
My assessment: the reduced mass of the declutched system allowed the diver to respond to a greater (more obvious) extent to fluctuations in the steam supply. Since the ultimate output was dc, such variability was not as great a concern (any concern?) as would have been the case with an ac system with consumers that required constant speed operation.
There was a unique event during which both drivers operated not at the standard value but at that value plus about 16 percent. It was even "wilder" at that value than at the standard.
Basically, the entire system was very powerful but very crude. At that time there was not the industrial base required to support development and deployment of an ac system.
Best,
Bruce
Thanks Bruce!!!
The DC vs AC output would have obviously never crossed my simple mind but it makes sense. We had been basically taught that it was a governor action effect which in fact I guess it was but when yours and Randy's conversation turned to eye catching signatures, I couldn't get past just how sloppy that signature was so I thought I'd ask.
Thanks again for taking the time.
John