Benefits of SSNs

zen

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A good title needed in lew I'll use "benefits of SSNs"
It's a first stab at trying to define what the SSN delivers for a state.

Like all naval ships, the submarine possess a quality of both tactical utility and strategic effect.

At the tactical level, the ability to remain submerged and not reveal itself, coupled with the ability to deliver ship killing 'effectors' (torpedoes and, land attack and Anti-Ship Missiles, mines and special forces), makes this a potent means to dominate the seas and threaten coastal infrastructure.

It's strategic quality is in part the familier 'in being' readiness for action, and the retention of ambiguity in where it may be.
This ambiguity used to be a quality possessed by all ships beyond the sight of land. Essentially their location becomes conjecture and assumption, since it is not verifiable.
With the increasing passage of time the uncertainty of the ships location increases, until it is sighted again or another ship sees it and brings that information back to land.

Modern sensors render the ship's location much more acquire-able in real time. Removing ambiguity.
But the submarine retains this quality. Sonar is much more limited in range than radar or vision. Where an aircraft can be detected hundreds of miles away, a submarine can slip past the mere tens of miles and sometimes a lot closer.

Infamously, the more daring submarine commander has risked detection to take pictures of an opponents ship's propellers. A feat requiring the submarine to risk actual collision.

'In being' is the state of readiness to move, and act. A standing Army possesses this quality as does in it's readiness, a fortress manned and provisioned. As such these forces exert an immediate and continuing pressure to be answered either by manoeuvre or by counter force.

As such the nuclear powered submarine delivers an effect far greater than it's actual capacity. It's stocks of torpedoes and missiles are limited, there is little extra accommodation for passengers.

But the possibility is that these effectors will be applied at key assets an opponent possesses.
Ship(s) so vital to the fleet, or transport laden with crucial asset(s).
The port you cannot afford to have blocked. Infrastructure you cannot have have damaged or destroyed.
Worse that unguarded part of your coast through which agents delivered by submarine might slip unnoticed into your country.

Because the submarine might be anywhere, your only defence is to be strong everywhere and this drains resources away from other tasks.
 
I'm not so sure. I don't see anything on that list that a long ranged AIP sub couldn't do. Saab's Blekinge Oceanic ER has a 10k nm range, as does the South Korean Dosan Ahn Changho class. The Soryu class has an estimated AIP range on the order of 10000km/6000nm, which I somewhat question since it is significantly more than other AIP subs, but if correct it is more than sufficient to hold an operational theatre at risk along the lines you suggest. 10000 nm is enough to make a global deployment to near an operational environment, then refuel for a long endurance patrol. Since AIP subs are somewhat quieter than nukes, they can be even more of a problem.

So the question then becomes what advantages do SSNs give over AIPs, especially when you can buy 3-4 AIPs for the cost of one SSN?

Range may or may not be one. If you are SK or Japan, and your concerns are NK/PRC/Russia, then you aren't going to need to refuel when you reach the operational area since your operational area is off your own coast. A similar logic applies to European navies operating in European waters. Perhaps even to the USN in the North Atlantic, or even operating from Hawaii/Alaska in the western Pacific. But if you are a European navy, or the USN, or PRC or Russia, and you want to deploy to or across the Pacific or under the Polar icecap (asssuming it doesn't melt away year-round), then there is a significant strategic and tactical advantage to not needing a port or an accompanying tender once you reach your operational area.

Another advantage, and this is a straight up capability that AIP doesn't have at all, is strategic and tactical speed. AIPs can't keep up with a carrier group doing flight ops; they max out at around 20 knots rather than the 30 or so carriers operate at, so they can't escort carriers. If you don't need subs to act as fleet escorts, then you can maybe get along with AIPs rather than nukes. If you do need them to be able to keep up with a fleet at 28-30 knots, then you have to have nukes since AIPs can't reach that speed.

Finally, if you are using subs as a counter to SSBNs, then SSNs are required since only they can trail an SSBN over a months long submerged deployment.

The combination of lower speeds and limited fuel also means it takes AIPs much longer to deploy to an patrol area. SSNs can transit across the Pacific at much higher speeds since they can cruise at much higher speeds, which means they can deploy faster. Disregarding fuel, slower deployment speeds also mean less time in the patrol area before needing to resupply with food.

For regional navies like those in Southeast and East Asia concerned with the PRC, AIP makes more sense. Strategic and tactical speed and strategic endurance aren't important given the operational area is off your coast, and since you can have three to four times as many AIP than nuke subs, SSNs don't really make sense. On the other hand, if you need global reach then SSNs can make sense, and if you have to escort 30 knot fleets, then SSNs are your only option.

I can actually see a use for USN AIP subs. American Soryus could operate in the Atlantic and North Atlantic even without access to friendly ports. With such access they would be even more effective. This would then free up the nuke boats for Pacific operations*, as fleet escorts, and in the anti-SSBN role.

*USN AIPs could also be useful in the western Pacific if they could operate from secure regional bases, or if Soryu/Taigai types have strategic ranges along the lines of 12000 or more nm, which would permit long submerged patrols even transiting from Hawaii or Alaska, again freeing SSNs for other critical missions.
 
AIP subs are getting better and better, with the non-negligible advantage of being quieter because no reactor.
Still SSNs remains leaps and bounds ahead for weeks or months long - submerged cruises; AIP subs still can't do that AFAIK.

One good start would be to compere Scorpene vs Rubis, or Attack vs Barracudas.
AFAIK France is the one and only country in the world making SSN and SSK that derives from each others... although Scorpene was NOT a non-nuclear Rubis, rather "the ultimate Agosta class SSK".
Ouessant was last of its kind... 20 years ago.

If the French navy was richer, it certainly wouldn't spat on some AIP Scorpenes or Attacks to get more attack subs hulls at sea yet at lower cost...
 
So specifics rather detract from the principles, which risks hijacking the thread.

It certainly is the case that nuclear power provides effectively limitless range and endurance only constrained by consumables and human factors.

An SSN for example could continuously power along at 25kts for days, weeks, even months.
25kts is 25 nautical miles per hour.
In one day that equates to 600nm
In one week 4,200nm
In one month 16,800nm.
In six months 100,800nm

And at no point does it need to surface.

By comparison AIP powered submarines would have to be unfeasibly large to carry enough fuel for such performance. Current designs are much slower for long range operation and would rapidly exhaust their fuel trying to match an SSN for even a day.

Such AIP and diesel submarines are more likely to consume their supplies in long transit to a distant area and have as a consequence much more limited time on station.

The matter to hunting SSBNs is a different game and is best done as quietly as possible. As such both will spend their time creeping around. Listening out for the other, while trying to remain as hidden as possible.
 
There are other aspects to the points zen made.

A diesel can probably sustain 20 knots or so submerged, but only for about 15 minutes to an hour. As I understand it, an AIP system does not actually propel the boat, but keeps the batteries charged and they are what powers the propulsion system. An AIP boat can engage in lengthier operations than a regular diesel electric, but only at low speeds. Otherwise, it too has to get air from the surface.

The reactor allows sustained high speed (a nuclear sub is often faster than the surface ships pursuing it), but also provides scads of surplus power for sensors and other uses. A nuclear boat is harder to quiet than the latest conventional ones (one of the reasons they cost so much), but it is very quiet. The question is if it is already below the sound level where it's almost impossible to hear at tactical distances, how much capability are you willing to trade by giving up the reactor to gain a sound level that's 25-50% more almost impossible to hear?

Then the fact that, starting with the Virginias, you never have to refuel over the life of the sub has got to be a big plus.


But they do cost more...
 
A nuke plant generates about an order of magnitude more power than a diesel plant (tens of megawatts compared to megawatts)* and a diesel engines produces an order of magnitude more power than most AIP setups (megawatts compared to hundreds of kilowatts). That huge discrepancy in hotel and shaft power can be leveraged for all of the uses mentioned above.

*EDIT: and of course the nuke plant can operate continuously where as the diesel must snort, so this discrepancy is actual far wider.
 
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"True " SSN i.e. the ones using just torpedo tubes are actually quite a niche as actually there is the possibility of installing VLS tubes even on standard displacement boats (yes, all submarines even when being the highest tonnage items of some navies are actually classed like so, not as ship) has lead to a proliferation of SSGN and even SSG (the 636.3).
SSP formula has also had a certain success, even if actually there has been a sort of comeback of conventional SS due to the improved storage capability of the most modern Li-ion batteries.
Virginia and Yasen are so setting a new standard while navies used to operate in enclosed seas (Mediterranean included) have found SSP perfectly apt to their own need.
So I will expect both SSN than big SSGN (as Oscar) to partially fade while there is the eventuality of having also "electric" mini SSN in which a closed cycle mini reactor willbe used not to propel directly the boat but instead just to recharge the high capacity batteries of what otherwise would be a conventional SS.
 
Would it be possible to operate a diesel or aip type drone that sits in shallower waters near choke points, basically dormant but 'sensors' operational? With no crew the power requirements and 'comfort' is removed. It would need to transit to the 'patrol', 'sensor' zone was reached but I think they can do that reasonably.
 
The USN is already experimenting with the pier launched XLUUV 'Orca'. However at this time it looks like they are mostly interested in deploying mines and sensor packages from it, which is a lot less demanding then detecting a target, sufficiently identifying it as hostile, and generating a fire control solution against it. Over a long enough time period though I suspect we will see UUVs developed (or modified) as barrier SSKs.
 
Would it be possible to operate a diesel or aip type drone that sits in shallower waters near choke points, basically dormant but 'sensors' operational? With no crew the power requirements and 'comfort' is removed.

Yes. This is basically the SMX-26 « Caiman » concept from Euronaval 2012. A similar looking, but smaller, demonstrator is currently being tested.

See threads below:



View: https://youtu.be/OM2x5QraDRU

2_703.jpg
 
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Not mentioned is the disadvantages of SSNs, cost. Don't know if figures 100% correct but understand USN Virginia Block IV ~ $3 billion whereas the new Japanese Taigei class SSK ~$640 million each.

No doubting the advantages of the SSNs as outlined by Zen, but do they compensate for only having an operational sub fleet size of a fifth/quarter that could be funded if USN stayed with conventionally powered subs or a mixed fleet of SSK/SSN as China and Russia operate, does "quantity has quality all of its own" apply.

The other problem with nuclear is the very special/expensive facilities needed to maintain them (USN has initiated a $21billion/20 year program to update its four public shipyards that mostly maintain its nuclear carriers and subs), classic example the USS Boise whose last operational mission was in 2015 and only expected to return to operations eight years later in 2023 due to limited nuclear shipyard maintenance facilities.
 
The cost factor is mitigated in US usage by time to station and time on station. The rate of advance of a nuke boat is generally going to be dramatically faster over long distances, and the amount of time it can stay deployed is generally limited to food and/or the crew endurance. Were the US for instance to have an all diesel fleet, it would have to be dramatically larger to have as many boats available as the nukes are. For countries that have much more local operations (which is the overwhelming majority of them), diesel subs make more sense.

Also it is very difficult to compare costs across different countries. The Attack class submarines were not going to be especially cheaper than a new Virginia, and the Collins class were still only about half has cheap as an early Virginia.
 
Time on station is indeed the compensation.
SSK would need forward deployment from an in theatre base, to still be as unresponsive as a slow SSN.
Whereas the fast SSN can deploy from home, and still be where you need it in good time.
Security is thus a hidden benefit, as in theatre bases for SSKs are going to under constant scrutiny.
Deployment from them is a clear indication of intent.
Deployment from Home, is ambiguous as to it's destination and consequently ambiguous as to where and why it is deployed.

So again ambiguity is another benefit.
 
Given the waters around eg Taiwan are 'mostly shallow', some areas having been 'high & dry' during last ice-age, stealth must be paramount. And, boats are 'near home', so range is less of an issue.

'Blue Water' range, speed & endurance seems to come down to Nuke-power, and damn the cost.

Other than missile-subs sending salvos of cruise-missiles into eg Iraq, the only 'war-shot' I can remember is the 'Belgrano'. IIRC, the Junta were very upset that RN's nuclear-powered attack subs -plural- had joined the fray...
 
Security is thus a hidden benefit, as in theatre bases for SSKs are going to under constant scrutiny
Not to mentiom under constant threat of attacks from...

Well anything that flys.

A sub tender for an SSK will need to chill at least 1000 miles away from enemy territory or be at extreme risk for an explosive delivery.
 
Yes and no, a few chaps and fishing boats can keep tabs on what enters or leaves a naval base.
But the closer to the likely area of operations and the more obviously limited to operations in that area the vessel in question is...
Then deployment carries obvious threat to those in that area of operations.
Consequently they will react to a deployment.
As such deployment is escalation.

But a distant state with multiple areas of operations and concerns around the world. Sending an SSN out, reveals no real clue as to where it is going.
Every state in an area of operations will take note. But they cannot be sure it is heading towards them or someone else.
Worse, once submerged, unless it's located by some happy accident, you don't know, even after it could have reached you if it's here or somewhere completely different.

Maybe it is out there, ready to sink your ships, strike inland or deposit agents into your territory.....
But maybe it is actually on the other side of the world.
And you may only know which, after it has already done it's dirty deeds ;)

Or worse, decades after when files are declassified and you realise, they (users of SSNs) never felt the need to bother with you and your various schemes.....and you were jumping at imaginary shadows for nothing.
 
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Not mentioned is the disadvantages of SSNs, cost. Don't know if figures 100% correct but understand USN Virginia Block IV ~ $3 billion whereas the new Japanese Taigei class SSK ~$640 million each.

No doubting the advantages of the SSNs as outlined by Zen, but do they compensate for only having an operational sub fleet size of a fifth/quarter that could be funded if USN stayed with conventionally powered subs or a mixed fleet of SSK/SSN as China and Russia operate, does "quantity has quality all of its own" apply.

The other problem with nuclear is the very special/expensive facilities needed to maintain them (USN has initiated a $21billion/20 year program to update its four public shipyards that mostly maintain its nuclear carriers and subs), classic example the USS Boise whose last operational mission was in 2015 and only expected to return to operations eight years later in 2023 due to limited nuclear shipyard maintenance facilities.
I number of contributors, including me, have acknowledged the higher cost of nuclear boats. But there are some cost compensations often overlooked.

Using your cost comparison, where do you get the bodies to man all those conventional subs? How about the ports, building and maintenance yards, ports, logistics facilities, etc? Resources to produce and deliver the fuel as well as to support the boats on patrol (you can't just keep a conventional boat for months at a time on station)?

The Navy/US has been ignoring the shipyard situation for years. Frankly, the situation would probably be just bad with regular boats. Sub maintenance is a very specialized process and the skills there aren't transferable to other ship types, so during slack years the workforce drifts into other fields. Loss of an experienced workforce is plaguing ship repair as well as construction (i.e. what's happening to the Virginias) since essentially the only customer (for large ships as well as subs) is the US Navy. You can only kick the can so far down the road before you reach the end. Finally you have to pay the piper. Slip one thing here, and there's a ripple effect there.

Since you mentioned nuclear carriers, let me point out how the situation goes there. There is now a grand total of one (1) drydock in the entire US capable of performing a RICOH on a Nimitz class carrier (no. the building ways are not capable of holding a completed Nimitz even if we could spare them). This was the result of deciding to save short term bucks by adapting a facility designed to hold supertankers, rather that building . You can only kick the can so far...
 
One thing only touched upon thus far is silence. Silence is how submarines operate. The quieter the boat, the better it's chance of survival. Nuke boats are quiet but not as quiet as conventional submarines. China's submarine surfacing in the middle of a US Task Force is a case in point. Australia's O-boat, HMAS OVENS claimed a successful attack on the USS Enterprise and returned to base flying a broom, indicating a "clean sweep" of operations. The COLLINS class, despite the claims that she suffers from excessive noise, regularly takes on the US Navy in exercises and beats it, submarines and all. Noise cannot be ignored. It is deadly. Nuke boats are noisy compared to conventional powered boats.
 
One thing only touched upon thus far is silence. Silence is how submarines operate. The quieter the boat, the better it's chance of survival. Nuke boats are quiet but not as quiet as conventional submarines. China's submarine surfacing in the middle of a US Task Force is a case in point. Australia's O-boat, HMAS OVENS claimed a successful attack on the USS Enterprise and returned to base flying a broom, indicating a "clean sweep" of operations. The COLLINS class, despite the claims that she suffers from excessive noise, regularly takes on the US Navy in exercises and beats it, submarines and all. Noise cannot be ignored. It is deadly. Nuke boats are noisy compared to conventional powered boats.

It would be incorrect to say "all diesel boats are quieter than nuke boats". Which diesel boat? Under what conditions? At what speed?

It would be more correct to say that nuclear submarines have a subset of self generated noise that is continuous that diesel electric submarines do not (when they aren't snorting). Whether that actually translates into radiated noise in a significant way is not something we can know - the turbine noise for instance could easily be subject to active noise cancellation, since that would be in a very specific frequency band and operating at a precise known frequency by the boat (electrical generation in particular would always be 60 hz for a USN boat, 50 Hz for most other nucs). Also the anechoic coating is likely a large misnomer; that layer is probably specifically designed to reduce specific frequencies from inside the boat rather than solely attenuate reflected noise from active pings (though I suspect it is a complex coating that attempts both).

All of this also ignores the fact that there can be a lot transient noise generated by a submarine, and these activities are generally held in common by all boats: hull popping with depth change, mechanical noise from planes/rudders, propulsor noise, off loading waste, human activity aboard the boat in general, etc.

So it isn't clear that diesels have a solid advantage over a well designed nuc boat; we don't know enough to make that judgement. And in any case, you'd have to be very specific as to what the sub's conditions were in terms of training, maintenance, and activity to fully quantify self generated noise.
 
One thing only touched upon thus far is silence. Silence is how submarines operate. The quieter the boat, the better it's chance of survival. Nuke boats are quiet but not as quiet as conventional submarines. China's submarine surfacing in the middle of a US Task Force is a case in point. Australia's O-boat, HMAS OVENS claimed a successful attack on the USS Enterprise and returned to base flying a broom, indicating a "clean sweep" of operations. The COLLINS class, despite the claims that she suffers from excessive noise, regularly takes on the US Navy in exercises and beats it, submarines and all. Noise cannot be ignored. It is deadly. Nuke boats are noisy compared to conventional powered boats.
Peacetime antisubmarine exercises cannot be taken at face value when evaluating their wartime effectiveness. They're artificially constrained in ways that hamper the surface ships far more than the submarines, most notably by confining the surface ships into a limited, known, predefined area of sea that greatly simplifies a submarine's search task.

In open ocean and unrestricted operations, conventional boats have one major weakness in trying to attack surface task forces: speed. An American carrier battle group, for instances, cruises at the top speed of most conventional submarines, making it exceptionally difficult for the submarine to actually get into attack range. This is significantly less of a problem for nuclear boats, in that they can actually chase down surface ships and mostly have to watch their flow noise levels.

As for the Chinese popup, for one thing there's no actual confirmation that the Chinese submarine went undetected in the articles I've found. I believe their speculation that it was, because, and this is the important part: no active antisubmarine measures were being taken at the time. That's a rather important caveat.

Further, all these incidents you name are anywhere from 15-20 years old, and the Song surfacing in particular seems to have been a wakeup call to re-emphasize ASW training. Back in 2015 the Ronald Reagan was tailed for half a day by a Chinese submarine; while no word was given whether or not the submarine was detected before surfacing, I suspect she was; how else would the Navy know how long she was tailing the carrier? That she then surfaced in shooting range of the Reagan is provocative but not conclusive either way: even if the Navy had detected her they had no real way to shoo her away, as is the case with aircraft.
 
One thing only touched upon thus far is silence. Silence is how submarines operate. The quieter the boat, the better it's chance of survival. Nuke boats are quiet but not as quiet as conventional submarines. China's submarine surfacing in the middle of a US Task Force is a case in point. Australia's O-boat, HMAS OVENS claimed a successful attack on the USS Enterprise and returned to base flying a broom, indicating a "clean sweep" of operations. The COLLINS class, despite the claims that she suffers from excessive noise, regularly takes on the US Navy in exercises and beats it, submarines and all. Noise cannot be ignored. It is deadly. Nuke boats are noisy compared to conventional powered boats.

It would be incorrect to say "all diesel boats are quieter than nuke boats". Which diesel boat? Under what conditions? At what speed?

It would be more correct to say that nuclear submarines have a subset of self generated noise that is continuous that diesel electric submarines do not (when they aren't snorting). Whether that actually translates into radiated noise in a significant way is not something we can know - the turbine noise for instance could easily be subject to active noise cancellation, since that would be in a very specific frequency band and operating at a precise known frequency by the boat (electrical generation in particular would always be 60 hz for a USN boat, 50 Hz for most other nucs). Also the anechoic coating is likely a large misnomer; that layer is probably specifically designed to reduce specific frequencies from inside the boat rather than solely attenuate reflected noise from active pings (though I suspect it is a complex coating that attempts both).

All of this also ignores the fact that there can be a lot transient noise generated by a submarine, and these activities are generally held in common by all boats: hull popping with depth change, mechanical noise from planes/rudders, propulsor noise, off loading waste, human activity aboard the boat in general, etc.

So it isn't clear that diesels have a solid advantage over a well designed nuc boat; we don't know enough to make that judgement. And in any case, you'd have to be very specific as to what the sub's conditions were in terms of training, maintenance, and activity to fully quantify self generated noise.
Active noise cancellation still radiates noise, just at a negative sine wave compared to the noise itself. Nuke boats radiate noise - from pumps, electrical equipment, etc. Some of that is eliminated through rafting design. Diesel boats also radiate noise, some worse than others. Modern boats are so silent that they slip past ships/boats/shore installations. The OBERON boats were the quietest for a long time, the new Swedish boats today are the best.
 
One thing only touched upon thus far is silence. Silence is how submarines operate. The quieter the boat, the better it's chance of survival. Nuke boats are quiet but not as quiet as conventional submarines. China's submarine surfacing in the middle of a US Task Force is a case in point. Australia's O-boat, HMAS OVENS claimed a successful attack on the USS Enterprise and returned to base flying a broom, indicating a "clean sweep" of operations. The COLLINS class, despite the claims that she suffers from excessive noise, regularly takes on the US Navy in exercises and beats it, submarines and all. Noise cannot be ignored. It is deadly. Nuke boats are noisy compared to conventional powered boats.

It would be incorrect to say "all diesel boats are quieter than nuke boats". Which diesel boat? Under what conditions? At what speed?

It would be more correct to say that nuclear submarines have a subset of self generated noise that is continuous that diesel electric submarines do not (when they aren't snorting). Whether that actually translates into radiated noise in a significant way is not something we can know - the turbine noise for instance could easily be subject to active noise cancellation, since that would be in a very specific frequency band and operating at a precise known frequency by the boat (electrical generation in particular would always be 60 hz for a USN boat, 50 Hz for most other nucs). Also the anechoic coating is likely a large misnomer; that layer is probably specifically designed to reduce specific frequencies from inside the boat rather than solely attenuate reflected noise from active pings (though I suspect it is a complex coating that attempts both).

All of this also ignores the fact that there can be a lot transient noise generated by a submarine, and these activities are generally held in common by all boats: hull popping with depth change, mechanical noise from planes/rudders, propulsor noise, off loading waste, human activity aboard the boat in general, etc.

So it isn't clear that diesels have a solid advantage over a well designed nuc boat; we don't know enough to make that judgement. And in any case, you'd have to be very specific as to what the sub's conditions were in terms of training, maintenance, and activity to fully quantify self generated noise.
Active noise cancellation still radiates noise, just at a negative sine wave compared to the noise itself. Nuke boats radiate noise - from pumps, electrical equipment, etc. Some of that is eliminated through rafting design. Diesel boats also radiate noise, some worse than others. Modern boats are so silent that they slip past ships/boats/shore installations. The OBERON boats were the quietest for a long time, the new Swedish boats today are the best.
Thru it should be note that that silence disapears real fast if you try to go faster then 15 knots just by water flowing over the hull.

So to be sneaky silent you need too probe around at like 5 knots.

Subs are ambush creatures, diesel-electric especially, they cant maintain.

If a Carrier task force catches a whiff of a sub ahead...

They can just go around.

And if the sub try to catch up?

Well a fast sub is a noisy sub and a noisy sub is a dead one.

Cause if the Helicopter are out and flying, Wargaming Rules often Prevent this irl doesn't outside of weather, they will pick it up. And will full that area with torps.

A nuke bote can kinda get around this by having the endurance to loop around the long ways to get back in front. A Diesel simply can not keep up.

Which is why in Exercise Carriers are limited to a small box to do circles in. Like 300 by 300 km.

Basically they are sitting ducks with clip wings.

In real life a CTF will be maintain 20 knots and sprinting around at 30 coverage nearly 1000 km a day.
 
One thing only touched upon thus far is silence. Silence is how submarines operate. The quieter the boat, the better it's chance of survival. Nuke boats are quiet but not as quiet as conventional submarines. China's submarine surfacing in the middle of a US Task Force is a case in point. Australia's O-boat, HMAS OVENS claimed a successful attack on the USS Enterprise and returned to base flying a broom, indicating a "clean sweep" of operations. The COLLINS class, despite the claims that she suffers from excessive noise, regularly takes on the US Navy in exercises and beats it, submarines and all. Noise cannot be ignored. It is deadly. Nuke boats are noisy compared to conventional powered boats.

It would be incorrect to say "all diesel boats are quieter than nuke boats". Which diesel boat? Under what conditions? At what speed?

It would be more correct to say that nuclear submarines have a subset of self generated noise that is continuous that diesel electric submarines do not (when they aren't snorting). Whether that actually translates into radiated noise in a significant way is not something we can know - the turbine noise for instance could easily be subject to active noise cancellation, since that would be in a very specific frequency band and operating at a precise known frequency by the boat (electrical generation in particular would always be 60 hz for a USN boat, 50 Hz for most other nucs). Also the anechoic coating is likely a large misnomer; that layer is probably specifically designed to reduce specific frequencies from inside the boat rather than solely attenuate reflected noise from active pings (though I suspect it is a complex coating that attempts both).

All of this also ignores the fact that there can be a lot transient noise generated by a submarine, and these activities are generally held in common by all boats: hull popping with depth change, mechanical noise from planes/rudders, propulsor noise, off loading waste, human activity aboard the boat in general, etc.

So it isn't clear that diesels have a solid advantage over a well designed nuc boat; we don't know enough to make that judgement. And in any case, you'd have to be very specific as to what the sub's conditions were in terms of training, maintenance, and activity to fully quantify self generated noise.
Active noise cancellation still radiates noise, just at a negative sine wave compared to the noise itself. Nuke boats radiate noise - from pumps, electrical equipment, etc. Some of that is eliminated through rafting design. Diesel boats also radiate noise, some worse than others. Modern boats are so silent that they slip past ships/boats/shore installations. The OBERON boats were the quietest for a long time, the new Swedish boats today are the best.
Thru it should be note that that silence disapears real fast if you try to go faster then 15 knots just by water flowing over the hull.

So to be sneaky silent you need too probe around at like 5 knots.

Subs are ambush creatures, diesel-electric especially, they cant maintain.

If a Carrier task force catches a whiff of a sub ahead...

They can just go around.

And if the sub try to catch up?

Well a fast sub is a noisy sub and a noisy sub is a dead one.

Cause if the Helicopter are out and flying, Wargaming Rules often Prevent this irl doesn't outside of weather, they will pick it up. And will full that area with torps.

A nuke bote can kinda get around this by having the endurance to loop around the long ways to get back in front. A Diesel simply can not keep up.

Which is why in Exercise Carriers are limited to a small box to do circles in. Like 300 by 300 km.

Basically they are sitting ducks with clip wings.

In real life a CTF will be maintain 20 knots and sprinting around at 30 coverage nearly 1000 km a day.

As you mention they are ambush creatures. OVENS ambushed ENTERPRISE on KANGAROO-2 and sunk it (although the yanks claimed it was only "damaged" to save face). OVENS was diesel powered. The USN supposedly concentrated on only nuke boats but even the PRC was able to surface inside the TF perimeter...
 
As you mention they are ambush creatures. OVENS ambushed ENTERPRISE on KANGAROO-2 and sunk it (although the yanks claimed it was only "damaged" to save face). OVENS was diesel powered. The USN supposedly concentrated on only nuke boats but even the PRC was able to surface inside the TF perimeter...
In 1976. During an exercise in which Enterprise was hugging the shore and in a predefined box.

As for the PRC incident, see my prior comment about there being no active antisubmarine measures being run.
 
As you mention they are ambush creatures. OVENS ambushed ENTERPRISE on KANGAROO-2 and sunk it (although the yanks claimed it was only "damaged" to save face). OVENS was diesel powered. The USN supposedly concentrated on only nuke boats but even the PRC was able to surface inside the TF perimeter...
In 1976. During an exercise in which Enterprise was hugging the shore and in a predefined box.

OVENS still managed to bag the ENTERPRISE...
As for the PRC incident, see my prior comment about there being no active antisubmarine measures being run.

Which suggests what about the superiority of the USN?
 
OVENS still managed to bag the ENTERPRISE...
Yes, and you're still missing my point, which is that that bagging was not in real-world conditions and would be far less likely to happen in an actual war situation. Also that this was almost 50 years ago and extrapolating that result to the modern environment is not terribly useful.

Which suggests what about the superiority of the USN?
Nothing, considering I was not trying to push the superiority of the US Navy, only complicate your simplistic view of the effectiveness of conventional submarines.
 
OVENS still managed to bag the ENTERPRISE...
In a situation that by all common command sense and SOP the Enterprise would have never been in if not for the fact there was a need to TRAIN THE OVEN'S CREW HALFWAY DECENTALY.

Kangaroo 2 was a Kangaroo Exercise in the same way a Kangaroo Court is a thing.

The USN had to lame itself so that the Oven had a decent chance of getting some training. Cause or else the Oven would have just been left sad in the dust as the Big E ran the other way.

Or Deleted.

The same can be said for the Swedish Boats and other Diesel Boats. If you look at the exercise and see what the carrier was not allow to use.

In Kangaroo the Enterprise task Group was not allowed to use its active sonar, the ASW Helicopter or the most damning of all the brand new ASW S-3 Viking and was limited to a small 300 by 300 mile area. Also No US Submarines was allowed to join in, as it was SOP for a SSN attached to a Task Force to go sub hunting and is expected for it to do most of the ASW work itself.

Literally 3 thirds of the ASW kit not allowed to be used so the HMAS Ovens had a chance in a area the size of a postage stamp.

When to take that into account, the Ovens accomplishment suddenly looks less like a big win and more like a pity fight that the USN Throw to give some confidences to a tiny navy.
 
OVENS still managed to bag the ENTERPRISE...
In a situation that by all common command sense and SOP the Enterprise would have never been in if not for the fact there was a need to TRAIN THE OVEN'S CREW HALFWAY DECENTALY.

Kangaroo 2 was a Kangaroo Exercise in the same way a Kangaroo Court is a thing.

The USN had to lame itself so that the Oven had a decent chance of getting some training. Cause or else the Oven would have just been left sad in the dust as the Big E ran the other way.

Or Deleted.

The same can be said for the Swedish Boats and other Diesel Boats. If you look at the exercise and see what the carrier was not allow to use.

In Kangaroo the Enterprise task Group was not allowed to use its active sonar, the ASW Helicopter or the most damning of all the brand new ASW S-3 Viking and was limited to a small 300 by 300 mile area. Also No US Submarines was allowed to join in, as it was SOP for a SSN attached to a Task Force to go sub hunting and is expected for it to do most of the ASW work itself.

Literally 3 thirds of the ASW kit not allowed to be used so the HMAS Ovens had a chance in a area the size of a postage stamp.

When to take that into account, the Ovens accomplishment suddenly looks less like a big win and more like a pity fight that the USN Throw to give some confidences to a tiny navy.
The proof is in the pudding. ENTERPRISE was at least damaged if not sunk by OVENS. Their were no limitations on what the ENTERPRISE could do, it was their decisions which drove what they did, no one else's. Their was no need for the OVENS crew to be trained as they were already top-notch. The ENTERPRISE had to approach the coast for the exercise, there was no other way to support the invaders' force. The ENTERPRISE was shown to be fools.
 
OVENS still managed to bag the ENTERPRISE...
Yes, and you're still missing my point, which is that that bagging was not in real-world conditions and would be far less likely to happen in an actual war situation. Also that this was almost 50 years ago and extrapolating that result to the modern environment is not terribly useful.

Which suggests what about the superiority of the USN?
Nothing, considering I was not trying to push the superiority of the US Navy, only complicate your simplistic view of the effectiveness of conventional submarines.
The clean sweep was shown to have occurred, the proof is in the pudding.
 
The proof is in the pudding. ENTERPRISE was at least damaged if not sunk by OVENS. Their were no limitations on what the ENTERPRISE could do, it was their decisions which drove what they did, no one else's. Their was no need for the OVENS crew to be trained as they were already top-notch. The ENTERPRISE had to approach the coast for the exercise, there was no other way to support the invaders' force. The ENTERPRISE was shown to be fools.
There was Limitation place on Enterprise.

I JUST LISTED THEM. That was in Kangaroo 2 US Opord which I have. Would post a scan but lack a scanner.

S3 Vikings was limited to four 4 hour flights per 24 hour period, Active Sonar use was denied (on enviromental reason), SSNs usage was not allowed (with the Sub while the Lamps was limited to Two flights of two birds per 24 hour period. That is in the US Operation Orders for Kangaroo 2. The Enterprise was not allow to fully use it kit and so of course was made to be fools.

Also, if the Ovens was such top notch, THEN KANGAROO TWO WOULD HAVE NOT HAPPENED CAUSE IT WAS UNNEEDED. Cause these types of exercirse are expansive. Or one of the other Oberon's would have been used. Besides you always need more training.
 
One thing only touched upon thus far is silence. Silence is how submarines operate. The quieter the boat, the better it's chance of survival. Nuke boats are quiet but not as quiet as conventional submarines. China's submarine surfacing in the middle of a US Task Force is a case in point. Australia's O-boat, HMAS OVENS claimed a successful attack on the USS Enterprise and returned to base flying a broom, indicating a "clean sweep" of operations. The COLLINS class, despite the claims that she suffers from excessive noise, regularly takes on the US Navy in exercises and beats it, submarines and all. Noise cannot be ignored. It is deadly. Nuke boats are noisy compared to conventional powered boats.
I addition to the other points raised, there are some other considerations here.

First, let's assume that we're talking about a conventional submarine running at slow speed on batteries (if the boat's snorting or running on diesels on the surface, "quiet" is not necessarily apt) compared with a nuke of comparable vintage operating quietly, the SS will normally be expected to be quieter. That doesn't mean the nuke is noisy. Sonically, an SS is sometimes referred to as "...a hole in the ocean". An SSN is also a "...hole in the ocean", just not as "deep". The SSN may not be as quiet, but the real question is whether or not it's quiet enough to perform its mission. If it is, the fact that an SS may be quieter than that become something that may be chosen to be traded away for other capabilities. In other words, is the SS noise level low enough relative to the SSN that it can regularly get close enough before it is detected by the SSN's superior sensors to regularly make a difference? It's also worth remembering that one of the reasons SSNs are so expensive is because of all the (necessarily) extra effort/costs done to quiet them.

There's also the issue of "quiet" of "tactical" speeds. This is a higher, albeit noisier speed that the quietest a sub can achieve (which in the case of a nuke involves cooling the reactor using convection only), which limits their speed significantly.

Stealing the definition from the Federation of American Scientists, "The tactical speed of a submarine is that speed at which the submarine is quiet enough to remain undetected while tracking enemy submarines effectively, with sources of self-noise reduced to the point that other submarines and ships can be detected using onboard passive sonar sensors". That speed is highly classified, but in the case of the Seawolf (and presumably Virginia) class is said to be above the maximum dash speed of most if not all SS boats Another reason they cost so much.

I would wager that a Seawolf, Virginia, Astute or even a late LA class could perform the same trick as the Song lass sub that surfaced five miles from the Kitty Hawk in 2006, but doing so would give away too much intelligence. Heck! Surface ships are often at a disadvantage against subs. The history of the Falklands War may have been quite different had the Argentinians' San Luis not have suffered weapons and targeting malfunctions.
 
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One thing only touched upon thus far is silence. Silence is how submarines operate. The quieter the boat, the better it's chance of survival. Nuke boats are quiet but not as quiet as conventional submarines. China's submarine surfacing in the middle of a US Task Force is a case in point. Australia's O-boat, HMAS OVENS claimed a successful attack on the USS Enterprise and returned to base flying a broom, indicating a "clean sweep" of operations. The COLLINS class, despite the claims that she suffers from excessive noise, regularly takes on the US Navy in exercises and beats it, submarines and all. Noise cannot be ignored. It is deadly. Nuke boats are noisy compared to conventional powered boats.
I addition to the other points raised, there are some other considerations here.

First, let's assume that we're talking about a conventional submarine running at slow speed on batteries (if the boat's snorting or running on diesels on the surface, "quiet" is not necessarily apt) compared with a nuke of comparable vintage, the SS will normally be expected to be quieter. That doesn't mean the nuke is noisy. Sonically, an SS is sometimes referred to as "...a hole in the ocean". An SSN (is also a "...hole in the ocean", just not as "deep". The SSN may not be as quiet, but the real question is whether or not it's quiet enough to perform its mission. If it is, the fact that an SS may be quieter than that become something that may be chosen to be traded away for other capabilities. In other words, is the SS noise level low enough relative to the SSN that it can regularly get close enough before it is detected by the SSN's superior sensors to regularly make a difference? It's also worth remembering that one of the reasons SSNs are so expensive is because of all the (necessarily) extra effort/costs done to quiet them.

There's also the issue of "quiet" of "tactical" speeds. This is a higher, albeit noisier speed that the quietest a sub can achieve (which in the case of a nuke involves cooling the reactor using convection only), which limits their speed significantly.

Stealing the definition from the Federation of American Scientists, "The tactical speed of a submarine is that speed at which the submarine is quiet enough to remain undetected while tracking enemy submarines effectively, with sources of self-noise reduced to the point that other submarines and ships can be detected using onboard passive sonar sensors". That speed is highly classified, but in the case of the Seawolf (and presumably Virginia) class is said to be above the dash speed of most if not all SS boats. Another reason they cost so much.

I would wager that a Seawolf, Virginia, Astute or even a late LA class could perform the same trick as the Song lass sub that surfaced five miles from the Kitty Hawk in 2006, but doing so would give away too much intelligence. Heck! Surface ships are often at a disadvantage against subs. The history of the Falkands War may have been quite different had the Argentinians' San Luis not have suffered weapons and targeting malfunctions.
Some interesting points. The Malvinas/Falklands affair pointed out how difficult anti-submarine warfare is, even without the actual presence of submarines! The Royal Navy were considered masters at ASW work, far superior to the USN but that "mastery" appeared to disappear in real life and in the conditions of the South Atlantic. The Chinese submarine's surfacing so close to a USN Task Force shows how easy it is for submarines to work when they have the opportunity.
 
The proof is in the pudding. ENTERPRISE was at least damaged if not sunk by OVENS. Their were no limitations on what the ENTERPRISE could do, it was their decisions which drove what they did, no one else's. Their was no need for the OVENS crew to be trained as they were already top-notch. The ENTERPRISE had to approach the coast for the exercise, there was no other way to support the invaders' force. The ENTERPRISE was shown to be fools.
There was Limitation place on Enterprise.

I JUST LISTED THEM. That was in Kangaroo 2 US Opord which I have. Would post a scan but lack a scanner.

S3 Vikings was limited to four 4 hour flights per 24 hour period, Active Sonar use was denied (on enviromental reason), SSNs usage was not allowed (with the Sub while the Lamps was limited to Two flights of two birds per 24 hour period. That is in the US Operation Orders for Kangaroo 2. The Enterprise was not allow to fully use it kit and so of course was made to be fools.

Also, if the Ovens was such top notch, THEN KANGAROO TWO WOULD HAVE NOT HAPPENED CAUSE IT WAS UNNEEDED. Cause these types of exercirse are expansive. Or one of the other Oberon's would have been used. Besides you always need more training.
K-2 occurred as part of the A**US treaty. OVENS had been in commission for over five years at the time of the exercise, her crew was experienced, her commander had undergone the PERISHER command course, any training would have been simply reinforcing lessons already learnt. ENTERPRISE was in a similar level of experience and she was still made to look foolish. QED.
 
In the Falklands conflict, the UK expended hundred's of antisubmarine munitions (some sources say they almost ran out and had to be resupplied by the US) and flew over 2,200 helicopter antisubmarine sorties and never detected San Luis when she made her attacks.
 

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