Live data from Hacker News

Russian ALFA Class interceptor submarine

hisutton.com

51–60 of 62 posts

Re: Russian ALFA Class interceptor submarine

#51
post #26

It was an experimental design and as the article says, it was very expensive. Titanium was not just expensive, but it was hard to use. Welding had to be done in an inert gas chamber. Imagine building an inert gas chamber for a submarine. More info about it here https://foxtrotalpha.jalopnik.com/russias-alfa-class-was-the... I think that's a better overall article than the original link. New reactor design was experim…

It gave the Russians a lead in Titanium manufacturing that still exists today.

Is that so? I recall the reading a piece on the SR-71 and it mentioned that the titanium was, ironically, sourced from the Soviet Union who supposedly were behind in titanium tech. Further, I remember a following tidbit about one of their jets still being made of steel because of their supposed lagging metallurgical skills. Have they since leapfrogged the US?

Re: Russian ALFA Class interceptor submarine

#52

Earlier quoted context omitted.

They're more innovative. Move fast and break things, right?

"Move fast and break things" doesn't sound right, when "things" are your own citizens. But it's only my opinion, probably.

People were the cheapest resource in Russia since about forever.

Re: Russian ALFA Class interceptor submarine

#53
post #26

It was an experimental design and as the article says, it was very expensive. Titanium was not just expensive, but it was hard to use. Welding had to be done in an inert gas chamber. Imagine building an inert gas chamber for a submarine. More info about it here https://foxtrotalpha.jalopnik.com/russias-alfa-class-was-the... I think that's a better overall article than the original link. New reactor design was experim…

IIRC the hull of much larger Russian nuclear subs (the ones that are always near the US East Coast) is made of titanium too.

Re: Russian ALFA Class interceptor submarine

#54

Earlier quoted context omitted.

It gave the Russians a lead in Titanium manufacturing that still exists today.

Is that so? I recall the reading a piece on the SR-71 and it mentioned that the titanium was, ironically, sourced from the Soviet Union who supposedly were behind in titanium tech. Further, I remember a following tidbit about one of their jets still being made of steel because of their supposed lagging metallurgical skills. Have they since leapfrogged the US?

If you read the linked articles here it was exactly that attitude that allowed the US to tell itself that it was impossible that the Russians had the capability to make a Titanium sub for about a decade.

https://news.ycombinator.com/item?id=17015111

Re: Russian ALFA Class interceptor submarine

#55

Earlier quoted context omitted.

They're more innovative. Move fast and break things, right?

"Move fast and break things" doesn't sound right, when "things" are your own citizens. But it's only my opinion, probably.

Is it better if they are not your own citizens?

Re: Russian ALFA Class interceptor submarine

#56
post #22

These were among the only Lead-bismith cooled nuclear reactors ever operated. Sodium-potassium eutectic or pure sodium coolant is a better heat transfer fluid but in a water environment it's just a little crazy due to sodium-water chemistry. The US Navy tried sodium coolant in the USS Seawolf [1] and it was smaller, quieter, and more powerful, but they had problems with the steam generators. Not an unsolvable problem…

I wonder if we'll see non-pwr naval reactors anytime soon. A high temp reactor would allow using a supercritical CO2 Brayton cycle which would take up much less space. On another note, what would happen if a MSR powered ship would sink and the fuel salt would come into contact with sea water? Would the salts dissolve into the water? Much as I like MSR's as a concept, if so this would make them a quite bad idea on a s…

To what end?

The USN has, to a material degree, perfected the compact PWR.

Their experience in fuel design, materials, cooling, support systems, control systems, and processes pose an enormous barrier to new systems other than those that could truly radically simplify the reactor system and yield a huge gain in reduced manpower and increased reliability.

I think the best marginal gains are coming and will come from developments in tactical and ISR systems.

Re: Russian ALFA Class interceptor submarine

#57
post #27
post #22

Earlier quoted context omitted.

I wonder if we'll see non-pwr naval reactors anytime soon. A high temp reactor would allow using a supercritical CO2 Brayton cycle which would take up much less space. On another note, what would happen if a MSR powered ship would sink and the fuel salt would come into contact with sea water? Would the salts dissolve into the water? Much as I like MSR's as a concept, if so this would make them a quite bad idea on a s…

Not in the US Navy. Part of the reason the US Navy standardized on PWR is that while it's not the most efficient it is something you can restart at depth if necessary. The lesson of how much that matters was driven home by the loss of the USS Thresher.

This had more to do with safety system failres and procedures regarding operation of critical valves than poison kinetics.

LM designs were abandoned prior to this accident due to availability and maintainability issues.

Re: Russian ALFA Class interceptor submarine

#58
post #25
post #20

Earlier quoted context omitted.

"Max depth" is kind of a nebulous concept though. There's the "test depth" which is as deep as they're willing to test the submarine. There's the maximum operational depth, which is some lesser depth that keeps a safety margin over the test depth. Then there's the "crush depth", which is the depth at which the submarine will actually fail, and is hopefully substantially deeper than the test depth.

.. and along those lines cannot recommend https://en.wikipedia.org/wiki/Das_Boot enough

Been a while since I've watched "Das Boot", but IIRC, there's a scene in the movie where, initially on the surface, they have a taught string strung across the sub. Then, as they dive, deeper and deeper, the taught string relaxes giving a rather frightening visual insight into how much the hull of the boat is compressing.

Re: Russian ALFA Class interceptor submarine

#59

Earlier quoted context omitted.

They're more innovative. Move fast and break things, right?

"Move fast and break things" doesn't sound right, when "things" are your own citizens. But it's only my opinion, probably.

Apparently they also designed heavily for survivability, more so than the American subs.

So sounds more like calculated risks.

Re: Russian ALFA Class interceptor submarine

#60

Earlier quoted context omitted.

> The success of the water cooled competitor eventually led to the predominance of water cooled reactors in the commercial fleet. By commercial you mean operational (as in non-experimental Navy vessels.) There's precious few commercial nuclear vessels in history (four, each from a different country and I don't think they were ever operational all at the same time), so talking about the dominance of a particular nucle…

I meant to refer to the commercial fleet of commercial nuclear power plants making electricity on land, almost all of which have designs directly descended from naval designs. I guess "fleet" isn't a great word to use in the context of naval vessels. Whoops!

Its not commonly known, but the initial generation of commercial power reactors in the US is basically the result of technology transfer from the Naval Nuclear Propulsion program.
Post reply on HN