[alpha1]

Has there been any long term health study done for personnel who are onboard nuclear subs?

[Jeroen]

Originally Posted by alpha1

Has there been any long term health study done for personnel who are onboard nuclear subs?

Most navies with a submarine service have been doing these sort of studies. Life on board non nuclear subs were not that good for ones health. Apart from the mental issues of being locked up underwater in a small tube with a bunch of guys, the environmental systems on some of the earlier subs left lots to be desired. So, you were just not breathing very clean proper air.

Nuclear subs, these days, very advanced environmental systems. If you go by what you read from the official channels, you will be receiving less radiation exposure during a 4 month tour under water on one of these nuclear subs, than if had lived for four months above the water. An hour on the beach sun bathing appears to be more risky than a career on a nuclear sub.

In theory that could well be true. But I would not trust anything on these matters coming from regimes such as Russia. They are notoriously callous when it come to personal safety for their citizens and worse for those in the armed forces.

Would be interesting to see some recent studies though. If you google you get lots of hits, but it all appears quite dated.

Jeroen

[ads11]

OT slightly but this will certainly pique V. Narayan's interests given how he's always wistful of what could've been had India kept up the HDW deal.

http://www.thedrive.com/the-war-zone...stic-signature

TL: DR - it's essentially a rare close up image of a German Type 212 submarine in dry dock during refitting that highlights a unique propulsor arrangement it has. For any F1 aficionados it reminds me of the rear of Gordon Murray's Brabham fan car. The principle of the shroud from what i understood is to reduce cavitation noise at the propeller and hence make the sub just a little bit quieter.

I highly doubt that Joe Public will have any access to IN information on the propeller types being fitted on it's new classes but it'll be neat to see if India decided to diverge from the Russian boss hub design and integrated something like this on our indigenous take on the boats. I wonder if the naval design directorate brings in consultants from the likes of ThyssenKrupp etc to offer their input on particular components. One would hope.

[V.Narayan]

Government approves Rs 50,000 crore plan for acquiring 6 AIP submarines

https://timesofindia.indiatimes.com/...w/67777942.cms

The Government has approved a Rs 50,000 crore programme to acquire 6 diesel electric submarines with air Independent Propulsion (AIP). The subs are to be built in India. I only hope the investment made into the Scorpene class and into the relationship with DCNS, France is used well and we close a decision in 24 months and not the 12 years since this was first tabled in 2007. The green signal comes not a moment too soon given that the average age of our SSK fleet is around 25+ years.

File photo of INS Khanderi, 2nd of the Scorpene class. (Source Wikipedia)

Originally Posted by ads11

OT slightly but this will certainly pique V. Narayan's interests given how he's always wistful of what could've been had India kept up the HDW deal.
TL: DR - it's essentially a rare close up image of a German Type 212 submarine in dry dock during refitting that highlights a unique propulsor arrangement it has.

Thank you for sharing. Very interesting. A new learning for me. Simple and yet effective. Don't get my rant going on the HDW fiasco. Like shooting ourselves in the head. We are paying for it today one whole generation later.

[V.Narayan]

^^^^
My advise is to go easy on posting satellite photos which Google & the like snap despite Govt of India protests. Posting satellite photos of combat ship location & movements is not the objective of this thread. Satellite photos of sensitive locations and assets have become the new 'normal' thanks to Google Earth but is not normal or sensible. Just one man's point of view but I feel it should be stated. Thank you for listening.

[Maveryq]

I agree Sir, and I thought about it for a long time before posting it. I observed that these pictures are quite common on different forums and hence posted these here.



Will keep in mind the general sensibilities henceforth.

[V.Narayan]

Russia & India to ink contract for second Akula class SSN on 7th March 2019

https://economictimes.indiatimes.com...w/68248638.cms

India is on course to finalise a deal with Russia to procure a nuclear-powered submarine in a $3 billion deal that will be fitted with custom-made indigenous communications systems and sensors, reports Economic Times.

The deal is for the Akula class submarine and India has already bought vessels of the same class. The intergovernmental agreement for the submarine lease is expected to be signed on 7th March 2019.

Following this, the submarine will be built on mothballed hulls at a Russian shipyard and will be ready by 2025.

Chakra III will serve the Indian Navy for ten years and will replace the Chakra II that was bought from Russia in 2012. Chakra II’s lease, which will expire in 2022, is under discussion to be extended for five years till the new submarine is commissioned.

Source: Economic Times


File picture of an Akula class submarine.

SSN stands for nuclear powered hunter-killer submarine ie one that can hunt & kill other submarines in addition to ships. Chakra - III would most probably carry some land attack weaponry too.

[SPARKled]

We have to understand that nuclear powered submarines are banned from being sold as per international conventions. So this 'lease' is a convenient way to buy these nuclear powered subs for India from Russia who has many of these unfinished hulls lying around since the collapse of Soviet Union and end of cold war. This is the exact reason why Russia is still out all weather friend and is our most trust worthy arms partner along with Israel and France. American military stuff on the other hand is sanctions prone and comes with numerous end user restrictions as Pakistan is discovering with respect to using F16s against is, besides they would never sell important military stuff like SSBNs and SSNs or ToT of any stuff to us anyway

[Maveryq]

I had read somewhere that the hulls are made of titanium. Is that the case? If so then old hulls that were made earlier are a significant amount of money locked up.

[V.Narayan]

^^^^^
The hulls of almost all submarines are made of welded steel alloys which is a proven material for construction and subsequent repair. Titanium was used by the USSR in the semi-experimental Alfa class super fast nuclear subs in the cold war. Cost of Ti is 10X that of steel and cost of welding more than 20X that of steel. Ti proved too costly even for the USSR. Four Russian subs of the Sierra class - fast deep diving SSNs, still in service/reserve, have Ti hulls. But to what extent they are actually operational is not fully known. Ti helps make the hull lighter and hence faster. It's resistance to corrosion also helps. But the cost and difficulty in welding kills!

The Alfas were tracked by the Americans doing 45 knots and routinely cruising at ~1000 metres of depth. ‎

[Maveryq]

Isnt it amazing that the Russians used Titanium for their best submarines and the Americans for their SR 71 blackbirds ( probably the best western military aircraft IMHO)

[Jeroen]

Originally Posted by V.Narayan

^^^^^

The hulls of almost all submarines are made of welded steel alloys which is a proven material for construction and subsequent repair. Titanium was used by the USSR in the semi-experimental Alfa class super fast nuclear subs in the cold war. Cost of Ti is 10X that of steel and cost of welding more than 20X that of steel. Ti proved too costly even for the USSR. Four Russian subs of the Sierra class - fast deep diving SSNs, still in service/reserve, have Ti hulls. But to what extent they are actually operational is not fully known. Ti helps make the hull lighter and hence faster. It's resistance to corrosion also helps. But the cost and difficulty in welding kills!



The Alfas were tracked by the Americans doing 45 knots and routinely cruising at ~1000 metres of depth. ‎

I am wondering to what extend weight is a factor for submerged speed? Submerged a submarine has neutral buoyancy, Isn't is simply a matter of power (Thrust) overcoming drag? Weight comes into de- accelerating and turning. So weight has more to do with momentum and changing it.

Or am I missing something?

Jeroen

[Sutripta]

Titanium is also difficult (= expensive) to machine.

I think the USSR had an excess of titanium. So much so that when it broke up they dumped so much titanium on the world market that an architect used it for cladding a building (Guggenheim, Bilbao) he was designing!

[V.Narayan]

Pakistan’s Navy claims it spotted and warned Indian Submarine in its territorial waters

By Franz-Stefan Gady; March 05, 2019

https://thediplomat.com/2019/03/paki...n-arabian-sea/

Pakistan’s Navy claims that it has spotted and warned an unidentified Indian Navy submarine in the Arabian Sea on March 4. In a March 5 press statement, the Navy claims that it “detected and blocked” the Indian submarine “from entering Pakistani waters.” The boat was purported detected in Pakistan’s maritime zone.
“The submarine could have been easily engaged and destroyed had it not been Pakistan’s policy to exercise restraint in the face of Indian aggression and to give peace a chance to prevail.” The service added that it is keeping a close watch on other Indian Navy units stating that the detected sub is one of “the latest submarines of [the] Indian Navy.” Pakistan also released video footage to support its claim.

India rejected Pakistani claims. “The Indian Navy remains deployed as necessary to protect national maritime interests,” the Indian Ministry of Defense (MoD) said in a March 5 statement. “Over the past several days, we have witnessed Pakistan indulging in false propaganda and spread of misinformation. The Indian Navy does not take cognizance of such propaganda. Our deployments remain undeterred

Indian media claims that the video released on March 5 was an old one. While at least some of the footage appears to be recycled, parts of it could be authentic.

What actually happened or did not we will never know. So I am not getting into a guessing game. But it is an example of how naval presence has the flexibility of showing teeth by simply being there. A warship (or submarine) is the last 400 feet of your nation's foreign policy.

https://www.facebook.com/DgprNavy/vi...0969591583426/

[am1m]

Originally Posted by V.Narayan

A warship (or submarine) is the last 400 feet of your nation's foreign policy.

That's an awesome one-liner!

The only sub I've seen or been inside is INS Kursura, the one set up for display on the Visakhapatnam beach. Can't imagine how people live inside that for days or weeks. Must be very taxing physically and psychologically. I guess modern subs are better equipped but still a tough job.