STRATEGIC COMPARISION
COST
Cost of typical AIP sub is 100 million USD to 250 million USD, compared to 1,6 – 3 billion USD for typical nuclear submarine; though estimates for possible US diesel subs were as high as 500 million to 1 billion USD.
Here is list of submarine costs:
AIP submarines:
T-96 class (Sweden): 100 million USD
212-type (Germany): 250 million USD
Moray class (Netherlands): 250 million USD
Dolphin class (Germany): 500 – 870 million USD
Scorpene class (France): 450 million USD
Nuclear submarines:
Los Angeles class: 1 billion USD
Seawolf class: 2,8 billion USD
Virginia class: 1,8 – 2,5 billion USD
Astute class: 1,17 – 1,82 billion USD
Further, while nuclear submarines are not really harmful for its crew, disposal of spent nuclear fuel is very costly. Operating costs are also lower for AIP subs – nuclear submarines can cost 21 million USD per year to operate, along with 200 million USD refuelling and modernizing at half-life of 15 years, which adds up to 830 million USD over nuclear sub’s lifetime. At the end of service life, it can be refuelled and overhauled for 410 million USD, giving it another 12 years of life, and adding 662 million USD to total lifetime operating cost.
ENDURANCE
AIP subs generally provide submerged (AIP) endurance of 14-30 days, and total endurance of 45 to 90 days, as AIP systems cannot yet replace oxygen-dependant diesel engine. Nuclear subs, on the other hand, typically have endurance – submerged or not – of 90-100 days, limited by the food storage for the crew. Gotland class has submerged endurance of 14 days at 5 knots, while Type 212 submarine has submerged endurance of over 30 days at 4 knots, and can cruise for cca 3 000 miles.
TACTICAL COMPARISION
Main advantage of modern submarine is stealth. While nuclear submarines have measures to reduce sound and magnetic signatures, nature of nuclear propulsion (steam turbine) makes them far more noisy than AIP submarine of same size. They also tend to be larger on a whole, making them even more detectable through either acoustic, infrared or magnetic sensors. Further weakness of nuclear submarine is that it has to cool down nuclear reactor, with hot water being dumped into ocean, leaving long trail behind the submarine; as such, it is even more detectable by IR sensors than just size difference suggests.
While Los Angeles class can dive to 450 meters regularly, German Type 214 (improved Type 212) can dive to 426 meters.
Nuclear submarines are typically faster than AIP subs, making them more suitable for open ocean. However, typical AIP sub is smaller and more maneuverable than typical nuclear submarine. This, combined with smaller acoustic signature, makes them far better suited for littoral waters, such as in North Sea, Mediterranean Sea or Western Pacific, where in some cases nuclear submarine is longer than the water is deep. As such, in islanded areas or choke points nuclear submarine can fall victim to smaller AIP subs, unable to detect and outmaneuver them. Nuclear submarines have cruise speeds of 20 – 25 knots, compared to 10 – 15 knots for AIP subs. Combining slower cruise speed with bursts of high speed can allow AIP subs to cover relatively large area, however, and effectivelly deny access to enemy nuclear submarines. HDM and MESMA systems used in AIP subs (submarines using them typically cost 250 million USD) are also far quieter than nuclear plant.
In shallow water, AIP sub is just as dangerous to surface ships as it is to nuclear subs. As Capt. Tom Abernethy, who commands the sub-hunting Destroyer Squadron 22 based in Norfolk , Va. , said: “Shallow water, you get a lot of noise reverberation and additional traffic, and you’re fighting in somebody else’s back yard which they know pretty well …. [In that environment, even a diesel sub] is absolutely a real threat, a formidable threat …. ”. Furthermore, unlike nuclear submarine, diesel submarine can hide on the floor, completely silent and immobile, until something passes nearby. And even with usage of active sonar, it is not easy to discern submarine from its surroundings.
Walter hydrogen peroxide turbine allows for 26 knots of submerged speed, however, though it is likely a “sprint” speed (which is in 30 – 35 kt range for nuclear subs) and not cruise speed. Perhydron fuel used in WW2 and later Walter submarines is combustive, and fuel lines must not have any right angle turns, as it can pile up and spontaneously combust in such angles – and even without that, Russian Walter submarines were called “cigarette lighters” due to their tendency to flame up. Further, turbine is very fuel-thirsty, limiting the range.
Out of modern AIP technologies, closed cycle steam turbines offer highest short term power output, but have lowest efficiency and highest fuel consumption. Stirling engine is quiet and simple, but large compared to its power output. PEM fuel cells currently have very low power output, but like all other AIP technologies, there is a lot of room for improvement.
In exercises, AIP and diesel subs have proven their worth. While exercuses are usually scripted (sometimes to an extent of being completely unindicative of actual combat capabilities of different weapons – this is case with USAF exercises involving 5th generation fighters), it was known for submarine commanders to deviate from script, with deviations producing rather interesting results. In 1981 NATO exercise Ocean Venture, an unnamed 1960s vintage Canadian diesel submarine “sank” the carrier USS America without once being itself detected, and a second unidentified vintage sub “sank” the carrier USS Forrestal. In 1989 exercise Northern Star, Dutch diesel submarine Zwaardvis “sank” carrier USS America. In RIMPAC 1996, Chilean diesel submarine Simpson “sank” carrier USS Independence. In 1999 NATO exercise JTFEX/TMDI99 Dutch diesel submarine Walrus “sank” carrier USS Theodore Roosevelt, exercise command ship USS Mount Whitney, one cruiser, several destroyers and frigattes, and Los Angeles class nuclear fast attack submarine USS Boise. In RIMPAC 2000, Australian Collins class diesel submarine “sank” two US fast attack submarines, and almost “sank” carrier USS Abraham Lincoln. In 2001 Operation Tandem Thrust, HMAS Waller sank two US amphibious assault ships in water barely deeper than length of submarine itself, though it was later sank herself, and Chilean diesel sub took out Los Angeler class nuclear fast attack sub USS Montpelier twice during exercise runs. In October 2002, HMAS Sheehan hunted down and “killed” Los Angeles class USS Olympia. In September 2003, several Collins class submarines “sank” two US fast attack subs and a carrier. In 2005, Swedish Gotland-class submarine “sank” USS Ronald Reagan.
At least one similar occurence happened outside exercises: in 2006, Chinese Song-class diesel submarine reached striking distance of carrier USS Kitty Hawk undetected. While US are thinking about emulating diesel submarines with UUVs, most likely outcome will be platform just as, or less, capable than AIP submarine, while costing just as much as nuclear submarine, and being far more unreliable than either. As Robert Gates said, US spend more and more money for fewer and fewer platforms. I might add: and ones that are more vulnerable in many scenarios than what US are currently using.
CONCLUSION
AIP subs, while having disadvantages – mainly regarding speed and range – compared to nuclear submarines, also have many advantages that make than a must-have for any serious naval force. They can also be a nightmare for ASW and any other surface or submerged units when employed properly.
History and War 
To my understanding he thing about AIP is this. The AIP is used to charge and run the battery. it does not directly propel the sub. They can stay submerged without having to snort for many times longer than previous conventional . However, to do that they have to stay at slow speeds like previous generations. It’s all about the discharge rate. They can speed up, of course, but then your endurance goes to crap and you get noisy
The nuke, on the other hand, can go at whatever speed it needs for the entire deployment. Its surplus of power also allows it to use much more powerful and capable (and expensive) systems that aren’t practical on other subs. The latest AIP subs are probably quieter than our latest nukes. But, the question is, are our nukes quiet enough? In other words, acoustically, and AIP is a “hole in the ocean”. However, a Virginia is also a “hole in the ocean”. The real question is it below the danger threshold for an AIP’s sensors. If it is, then the money require to go quieter might better be spent elsewhere. They’re not invisible; HMS Astute, for example detected and held USS New Mexico repeatedly. Oh, wait a minute, Astute is the UK’s latest SSN type and also has super sensors (may be better than ours!). Another interesting note is the “tactical” or “quiet” speeds of the newer nukes. Whereas a AIP has to creep along at very low speeds for tis best quietness, the newer nukes can actually meet their desired levels of quietness at cruising speeds that are considered dash speeds for conventionals (who are really noisy at those speeds). It’s one reason they are so very expensive.
As far as the depth pf the LA class boats, that’s a function of a decision made in the construction of the earliest boats to switch to a lighter gauge steel for cost reasons. They were designed for deeper. it’s not so surprising that a sub class that came into service 40 years ago doesn’t dive any deeper than subs comong on line today.
Maneuverability-wise in the littorals, there isn’t that much difference keel to sail top between SSNs and AIPs. Also, my understanding is that contrary to popular belief, SSNs can “bottom”. The reactor is run at a low enough speed that it can be cooled by natural circulation. Naturally, this cuts way down on available power (battery discharge starts figuring in here as well) speed and is cooled by natural circulation. It’s one of the reasons they don’t do it very much. There are a couple of other reasons. On the bottom, most of the sonar array is effectively blanked and the tubes are unusable. Plus, when you do come off the bottom, that operation itself can be pretty noisy. Better off to just hover of drift close to the bottom.
As you state, subs of all kinds are really, really dangerous. I might add one other example: During the Falklands War, ARA San Luis repeatedly attacked the British fleet, getting away unscathed very time. Were it not for an incredible blunder in torpedo maintenance by Argentine personnel, the course of the war would have been radically different, the British being forced to withdraw to open seas until their SSNs could go in and kill her. Whether their fleet could have sustained being deployed for the extended time the war would last is a question to ponder
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1) Correct. But AIP sub is still quieter than nuclear submarine, for two reasons: first, it is smaller, and second, even when idle, nuclear submarine has to flush coolant through reactor at least from time to time – which generates noise.
2) USS New Mexico is a nuclear sub.
3) There is difference because nuclear submarines are, as a rule, larger.
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the san luis was hanted by the nuclear subs and it surbive 40 days of patrol, an the new torpedos of the royal navy were as useles as the new argentinian topedos, the only torpedo that work where the old world war 2 torpedos carry by the royal navy
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The same old story, latest technology torpedos never work at the beginning of a conflict. You must go back to previous tested tech.
remember the problems torpedo related in the German Navy and the US boats during WWII
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There’s an interesting quote I would like to share with you about the relatively poor performance of nuclear submarines in littoral waters:
http://books.google.ca/books?id=Hr-uaYXoyIQC&lpg=PT3&ots=rajEf0ofkO&dq=lessons%20not%20learned%20roger%20thompson&pg=PT35#v=onepage&q=lessons%20not%20learned%20roger%20thompson&f=false
Look at the quote just above the submarine picture:
Acoustic advantage is useful but not an “I win” button
Poor quality of personnel in the captain’s opinion was the biggest cause of losses
Now that captain in particular still feels that nuclear submarines have the upper hand, but I think he’s certainly right that it’s going to come down the quality of the crew.
If you have the chance to by the way Picard, I do recommend that you read that book, Lessons Not Learned. It’s a pretty sober reading.
Also interesting, have you ever heard the claim by the Americans that there have never been any SSBNs shadowed successfully by the Soviet Union during the Cold War?
That isn’t true. The Ethan Allen-class submarines were shadowed at least once. Of course, the Americans did not know about it, simply because they did not detect the submarine at the time. Post-Cold War interviews though revealed it.
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the reason for using nuclear-powered hunter-killer submarines…. is, to kill Russian ballistic missile (nuclear tipped) submarines, before they can launch their nuclear missiles from unexpected locations.
Therefore, it is vital to track down, and hunt down, even in peacetime, the missile submarines so they cannot hide so well in the ocean.
AIP submarines are too slow in this mission (peace time hunting down operation, against russian missile subs)
America wants to continuously track and hunt the Russian missile submarines, so they’re not so much of a threat in nuclear war.
Loss of one aircraft carrier here or there, is basically inconsequental compared to importance of nuclear missile submarine (which would lay waste to cities and large areas)
This is basic knowledge from Tom Clancy book, but I think the importance for nuclear powered submarines is clearly demonstrated 🙂
America wants to diminish Russian nuclear second strike. The way to go about diminishing nuclear first strike, well you need a dedicated missile shield for that, which is not invented yet.
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But that means that United States are unprepared for a far more likely conventional war. Like in Vietnam – all US fighters were bomber-intercepts, which did not do well against MiG-17 and MiG-19, even when the training improved.
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I have close to zero knowledge about Sub propulsion. I was wondering nuclear energy can be used for charging batteries? Batteries are quieter than steam turbine i guess….
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It can, but shutting down and powering up a nuclear reactor is quite an ardous task.
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I do consider all of the ideas you’ve introduced on your post.
They are very convincing and can definitely work. Still, the posts are too quick for newbies.
Could you please prolong them a bit from next time? Thanks for the
post.
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The Scorpene submarine has been jointly developed by DCNS of France (formerly DCN) and Navantia (formerly Bazan, then Izar) of Spain. Two Scorpene submarines were ordered by Chile. The vessels replace two Oberon Class submarines which were retired in 1998 and 2003.
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Thanks.
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In exercis in 2014 between Dutch walrus class submarine and HMS Astute , the old dutch submarine sunk the brandnew English submarine wich was supposed to have superior sonar systems, was a sub vs sub excercise in open wathier, the only advantage walrus had was it was near shipping lanes, but walrus sunk HMS Astute twice with certain kills, and could have more kills but didnt open fire because they were not 100% kills.
I will post a link next reply because the excercise documented
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Interesting, but not really surprising considering the advantages of the DE/AIP submarines. And Astute won every single “engagement” against US nuclear submarines, if I’m not mistaken.
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http://www.rtlxl.nl/#!/onder-zee-307841/f32ad6cf-a4ce-346d-8b25-f9570a353718
It’s a documentary about Dutch navy submarine’s on Dutch television, note the failure from the british submarine to authenticate correct on the challenge of the dutch submarine, if that’s the standard on british submarine’s ?
Excuses made for language and typing errors
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“to authenticate correct on the challenge of the dutch submarine, if that’s the standard on british submarine’s ?”
Just serves to prove what I’ve always been saying – visual IFF is the only reliable IFF. That being said, acoustic signature of the submarine can be used for IFF purposes as well, just as fighter radar can be used if active.
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Most comments miss the point. Comparing a nuke to an AIP is apples and oranges. Each has significant superiority in a given encounter. But one this is clear; for the price of 10 SSNs you can have at least 40 AIPs. Imagine a war with China and 40 AIPs are deployed in the coastal waters of the United States. The Rickover mafia needs to open its mind.
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Agreed. Nuclear subs are for the open ocean whereas AIP subs are for coastal waters – but for some reason, US Navy appears to consider only the open ocean as being worth of its attention. What is ironic is that this goes against Mahan’s thought, even though USN is allegedly influenced by him – Mahan considered control of coastal waters to be crucial so as to support ground troops, albeit primary task of the navy would be destruction of opponent’s maritime forces. Translated to a modern-day US Navy, this would result in a navy heavy in nuclear attack and AIP submarines, with primary surface force being composed of relatively small conventional carriers equipped with CAS aircraft to support ground troops.
Regarding Rickover, it is ironic that he had “little tolerance for mediocrity, none for stupidity.”, yet he himself developed into an idiot. He was an excellent nuclear engineer but overestimated importance and capabilities of the nuclear vessels, to the point that by the 1960s he had become a conservative force opposed to conventional ships. Also, his system trains US submarine captains to be nuclear engineers rather than ship commanders – as a consequence, US attack submarine force is qualitatively significantly inferior to its British and French (and likely Russian as well) counterparts.
More reading on Rickover:
http://www.airpower.maxwell.af.mil/airchronicles/aureview/1983/jul-aug/schratz.html
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I highly suggest reading “The First Nuclear Era” by Alvin Weinberg, the tutor to Hyman Rickover during his time at Oak Ridge learning reactor physics. On nuclear marine propulsion, Magdi Ragheb has a good primer on US nuclear propulsion here: http://mragheb.com/Nuclear_naval_propulsion.pdf
Rickover, to be short, was a man sharpened to a fine point – tirelessly dedicated and laser focused but without any peripheral considerations. He used rudeness as a communication method. But he got the job done and had the skill of taking considerable, but considered gambles. The result was a submarine force that controlled the vast majority of the world’s oceans. On that, I think, it is difficult to fault his methods.
As to the AIP vs nuclear debate, both have their strengths – in their intended roles. It is important to remember, however, that the hull size of even AIP subs is trending upwards. The result is that the cost advantage of AIP has been increasingly eroded. The German type 218SG is contracted to cost 1 billion, for example, while the French Scorpene, arguably the most formidable AIP sub right now, is $450 million.
AIP is stealthier and cheaper, and the ideal defensive submarine, being able to operate in littoral waters and increasingly in blue waters. But no AIP sub can match the speed and range of nuclear, so nuclear subs would appear to have better offensive roles – hunting other submarines and fleets and blue water patrols. Given the increasing standoff ranges of weapons, blue water interception is increasingly required.
I would say that the ideal submarine would probably be a relatively small (less than 4000 ton displacement submerged) nuclear submarine with x-shaped planes for littoral use and running the S8W submarine reactor with dual mode natural circulation for stealth and forced circulation for speed. Torpedo tube diameter would be as for the French Barracuda to provide for cruise missile launch. So you have an attack submarine that can also influence events on land, with the speed and endurance to shadow enemy subs in blue waters, with the size and stealth to operate in littoral waters. The French Barracuda design is disadvantaged by being a little too large and using inferior nuclear technology to American reactor cores. Were it designed with German philosophy in mind (no smaller than needed, no larger than required) and with an American reactor it would match AIP subs for cost and beat them in all other metrics.
U-Zr alloy fuels that are only now entering civilian testing have been run for decades in submarine service, while it has been only American nuclear engineering that has mastered natural circulation. Their mastery extends to the NuScale natural circulation civilian SMR and the Westinghouse AP1000 that uses natural circulation for scram – and now that China is building AP1000s on license, you can bet on Chinese natural circulation submarine reactors in the future as well.
The mistake of the American submarine program was not in their choice of using nuclear only submarines, but in their choice of hull size restricting them to blue water operations only, and their bloody-minded constant upscaling, and their focus on SSBNs. I think the latest SSN(X) design is pushing 20000 ton displacement – sheer madness. They also emphasise vertical launch instead of tube launch for their cruise missiles – which mandates an increase in size and complexity. Basically they pushed a platform instead of improving the payload – although this has been addressed by making Tomahawk torpedo tube capable for their attack subs.
Anyway, the latest Barracuda SSN is 1.3 billion in today’s money, which erodes the AIP sub cost advantage to around 3-to-1 if you take 400 million as an average cost of an AIP sub that has influence beyond littoral waters. Downscaled, and with a better reactor core, 2-to-1 or even 1-to-1 is possible. The massive 8000 ton Virginia-Class SSN was 1 billion for the block 2 iteration in then-year dollars. So a 500 million 4000 ton SSN is not impossible.
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“Rickover, to be short, was a man sharpened to a fine point – tirelessly dedicated and laser focused but without any peripheral considerations. He used rudeness as a communication method. But he got the job done and had the skill of taking considerable, but considered gambles. The result was a submarine force that controlled the vast majority of the world’s oceans. On that, I think, it is difficult to fault his methods.”
Rickover’s main achievement is US Navy’s perfect nuclear reactor safety record. But he himself obviously did not really understand pros and cons of nuclear and conventional submarines, or believed that littoral warfare is irrelevant for USN. Either way, he was wrong (albeit, to be fair, control of the open ocean was the primary task of US Navy through the Cold War – Atlantic does not have many islands, and main purpose of the US Navy in World War III would have been to enable transfer of troops to Europe).
And US submarine force never controlled the vast majority of the world’s oceans, not alone at least, and in a shooting war Soviet navy would have likely come out as a winner. Soviet submarine force outnumbered US submarine force by 3-1 during most of the war, and Soviets never stopped building conventional submarines.
“It is important to remember, however, that the hull size of even AIP subs is trending upwards. The result is that the cost advantage of AIP has been increasingly eroded. The German type 218SG is contracted to cost 1 billion, for example, while the French Scorpene, arguably the most formidable AIP sub right now, is $450 million.”
It would be interesting to see why is so. With minituarization of modern technology, it should be possible to make submarines smaller, not larger. And if 218SG is contracted to cost 1 billion USD, that is likely not just the production (building) cost but also the overhead, so comparing it with Virginia’s or Barracuda’s production cost is incorrect.
“AIP is stealthier and cheaper, and the ideal defensive submarine, being able to operate in littoral waters and increasingly in blue waters. But no AIP sub can match the speed and range of nuclear, so nuclear subs would appear to have better offensive roles – hunting other submarines and fleets and blue water patrols. Given the increasing standoff ranges of weapons, blue water interception is increasingly required. ”
Yes and no. Nuclear submarines are indeed the ideal choice for hunting warships and for blue water patrols. But humans live on land, and fleets and armies typically rely on maritime resupply – other methods are too expensive. This means that littoral warfare is always going to stay relevant, and AIP submarines are also an excellent choice for cutting off logistical train that actually sustains the fleet in the area of operations. Nuclear submarines are too expensive and have too large maintenance downtime to provide true control of the sea, especially in areas where the enemy can use islands to hide. This goes for the attacker and defender alike: to launch an aphibious attack, one has to establish control of the littoral waters first; and easiest way to prevent the attack from being launched is to deny the enemy control of the littoral waters.
I would not rely too much on standoff weapons: much is unknown about their real performance in a wartime scenarios. Falklands war has shown that guided munitions are easy to decoy with proper countermeasures, at least radar-guided ones, and even when ships were hit by missiles, said missile strikes had to be followed up by aircraft carrying bombs. Missiles can turn a ship into a hulk, but only torpedoes can reliably sink the ship. And standoff weapons do absolutely nothing about enemy submarines, which can easily sever the trade even if the invasion is never even considered.
“Were it designed with German philosophy in mind (no smaller than needed, no larger than required) and with an American reactor it would match AIP subs for cost and beat them in all other metrics.”
Major factor in nuclear submarine cost is nuclear reactor. So to match the price of an AIP sub it actually has to be a lot smaller. NR-1, the smallest nuclear submarine on record, was 400 tons in displacement – and it was a scientific, not military, submarine. Smallest nuclear attack submarine in service is Rubis class, which is 2.670 tons in displacement; smallest military nuclear submarine I could find is Skate class with 2.290 tons surface displacement. For comparison, smallest military AIP submarine is Vastergotland class with 1.145 tons displacement and largest AIP boat is Soryu class with 4.200 tons displacement. Smallest DE submarine in service is Kobben class with 485 tons displacement and largest is Oyashio class with 4.000 tons displacement. Note that both largest conventional boats are Japanese, and both are far less than twice of the Rubis class displacement; on the other hand, Rubis class is well over twice the displacement of smallest AIP submarine and over five times the displacement of smallest DE submarine. It is unlikely that any military nuclear submarine could be much smaller than Rubis class while still justifying the expense of nuclear propulsion.
And that still does nothing to adress the fact that AIP and DE submarines are a lot queter than nuclear submarines, at least when running on batteries (and possibly even when running on AIP, depening on the type of propulsion used). In coastal areas speed and dive depth advantage of a nuclear submarine is irrelevant, while transit speed advantage of nuclear submarine is in good part negated by their much higher proportion of maintenance downtime.
“The mistake of the American submarine program was not in their choice of using nuclear only submarines, but in their choice of hull size restricting them to blue water operations only, and their bloody-minded constant upscaling, and their focus on SSBNs.”
Actually, all of that is connected. Hull size is connected to USNs choice of nuclear propulsion, both having been made because USN sees itself as an exclusively blue-water navy. Had USN considered green water operations, it would have built smaller submarines, but it also would not have insisted on an all-nuclear propulsion.
“Anyway, the latest Barracuda SSN is 1.3 billion in today’s money, which erodes the AIP sub cost advantage to around 3-to-1 if you take 400 million as an average cost of an AIP sub that has influence beyond littoral waters.”
Primary purpose of AIP submarines is control of littoral waters, so that’s kinda missing the point.
“Downscaled, and with a better reactor core, 2-to-1 or even 1-to-1 is possible. The massive 8000 ton Virginia-Class SSN was 1 billion for the block 2 iteration in then-year dollars. So a 500 million 4000 ton SSN is not impossible.”
Actually, it is impossible. Major cost of a nuclear submarine is its reactor, and reactor does not really scale with size. Otherwise everybody (or at least French, Germans, Chinese, Russians…) would be building 2.700 ton 340 million USD nuclear submarines. Make that 2.700 tons and 500 million USD due to inflation etc.
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It is true that a nuke boat is more expensive than a smoke boat even considering lifetime fuel costs, but there is a large difference in time-on-station. You’ve already pointed out that AIP boats have a shorter underway endurance, but their vastly slower speed means that much more of their already limited endurance is spent simply getting to a faraway destination. AIP boats might be the best solution for protecting the homeland but for a nation that likes aircraft carriers and force projection as much as the US, nuclear boats are the only option. From California to northern Asia at 30+ knots the whole way, then extensive time on station once there, then 30+ knots to southern Asia, then extensive time on station once there, etc
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Problem for US is that many of its operations happen close to shore, where AIP boats are in their element. Problem might be alleviated somewhat by designing very small nuclear submarines, but to my knowledge no such designs are in existence or works.
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Nuk is better then AIP for two reasons, faster therefore more capable of hunting, retreating and so on. To loss and enemy with a father sub is better because the zone search gets that much bigger. And the nuk are LESS noisy, yes they need coolant and it makes noise that is in the sub and absorb by the absorbing material. AIP are detectable by shell sonar, Nuk by deep sonar like capta 4. Baracuda class is 1000 times quieter then the current class. If AIP were better do you think the royal would spend that much money on 6 barracuda when it could get 12 shortfin barracuda for the same price ?
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Nuclear submarines are typically larger, and more costly, so not an ideal choice for littoral operations. There is no way they can be less noisy than a conventional submarine on batteries, as for AIP that depends on which system is used.
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the batteries need to be charged at some point !
the AIP against nuk depending on the generation but if you take the same generation nuk is always better.
For the rest, Baracuda and shortfin baracuda are off the same size… Speed is probably better then manoeuvrability to avoid torpedo, torpedoes would do the work in littoral space. But you are right cheaper and better in littoral operation if we compare only the sub but there are weapons systems…
A mix would be the best in operation but the costs of maintenance …
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What is “better” always depends on the situation. DE and AIP submarines are far better in coastal areas, while nuclear submarines have advantage in the open ocean. Likewise, conventional submarines are primarily defensive, while nuclear submarines have advantage in offense. This situation is made a little less clear by the fact that modern AIP submarines can operate underwater for long periods of time, and even nuclear submarine is limited by the perishables onboard, but even so nuclear subs still have advantage in endurance and especially range.
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agreed !
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An older post from a blog where submariners post.
“Blogger PigBoatSailor said…
One of the unfortunate reasons that SSKs have such a good reputation against SSNs is the nature of the excercises in which they are pitted against each other. In order to provide “training for all” a close encounter is forced – usually with the SSN screaming in at high speed from a distance – immediately giving the SSKs at an advantage.
Again, without going into too much detail, I have done both the afore mentioned excercise (blew), and a week-long one with a diesel in which we were just hunting in a big chunk of ocean. In the second, more realistic, excercise, we wiped the ocean floor with the diesel. And these guys were not sloutches.
Also, US SSNs have gotten a lot better at combined ops with surface and air assets. That will absolutely end an SSK right there.”
http://bubbleheads.blogspot.com/2005/07/does-size-matter.html
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That is quite correct… and quite wrong as well. No submarine is best in all situations. It is true that SSNs have advantage in the open ocean, but SSKs have inherent advantage in littoral waters where your average SSN can’t even properly turn around due to its size. And most naval operations were in littoral waters.
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