Multihull aircraft carrier.

[Elheru Aran]

One thing you should consider when discussing the issue of torpedoes vs carriers is that all the major world powers during the cold war and presumably today stockpile torpedoes with atomic warheads for exactly this purpose.

And the odds are extremely strong that they'll never be used unless the power deploying them is either committed or expecting nuclear warfare, as that's the only realistic response to using an atomic warhead even tactically.

[Sea Skimmer]

I can only think of four total nuclear torpedoes ever to reach service, it was really never a very appealing idea compared to putting the nuclear warhead on a short range ballistic missile weapon like SUBROC or RPK-2. Such a inertial guided missile solves your targeting and positive control problems. Until fairly recently such a missile was also not easily intercepted by shipboard defense systems either. And you could much more easily hit a shore target that way.

One's I've heard made it to service are Soviet T5 which was a 21in straight runner, Soviet 65-73 which was also a non homing 65cm type, Soviet Shkval which is kind of just silly and very limited in range, and the US Mk45 ASTOR which was a completely wire guided 19in torpedo with no autonomous capability at all. Only the 65-73 would be a serious weapon against a modern day fast carrier group, and in all reality even with a large nuclear warhead firing such a torpedo from 50km away is still not a certain kill. The USN adapted very wide formations in the 1980s to go along with AEGIS and other changes in long range weapons and tracking, so even a large nuclear weapon isn't going to sink more then one ship. Against a convoy it might be a different story but who cares, the ports will already be vaporized.

Faced with this situation the the enormous possible homing area of a spread of normal torpedoes is not exactly bad either.This is why the Mk48 torpedo replaced the Mk45 in service, though in the ASW role. You can fire such weapons widely and its good enough for most purposes. If you wanted huge standoff the Soviet conventional 65-76 seems like the way to go with a non networked weapon. Network guided torpedoes are coming fast, at which point hundreds of miles of range become plausibly useful and plausible to build, but nobody has that now.

The Nimitz class was blast hardened against a 10psi nuclear air blast per documents Shep found. The TDS was tested for 2000lb charges and calculated against 2,400lb. A TDS will reduce nuclear water and air shock damage to the hull, but that won't help the ends of the ship or the planes on deck, the hanger is included in the 10 PSI calculation if the doors are closed.

[Sea Skimmer]

Idea to think on, take a notional 200nm range torpedo with low-high speed profile and a buoyant antenna it uses once an hour to update its position and orders. Now load LCS with a rack of those and a UAV for target spotting and to be a relay for data to torpedoes if needed.

Now we have that crappy little LCS and its mission deck with a weapon system that would utterly obliterate any battleship and even be able to attack them in Tirpitz in the Norwegian fjord like conditions. Being able to accomplish this is fairly near term technology. You could probably take a stab at Tirpitz right now with UUVs the USN already has in public but none of them have an ability for high speed terminal runs.

Interest is real if with submarines, including UAVs, as the number one platform, for example as mentioned here.

COMSUBFOR Connor: Submarine Force Could Become the New A2/AD Threat
By: Megan Eckstein
May 14, 2015 4:37 PM
The Ohio-class guided-missile submarine USS Florida (SSGN 728) arrives at Naval Submarine Base Kings Bay in April 2011. Florida returned after a 15-month deployment that included participated in Operation Odyssey Dawn, making the boat the first guided-missile submarine to launch Tomahawk land attack missiles. US Navy photo.

The Ohio-class guided-missile submarine USS Florida (SSGN 728) arrives at Naval Submarine Base Kings Bay in April 2011. Florida returned after a 15-month deployment that included participated in Operation Odyssey Dawn, making the boat the first guided-missile submarine to launch Tomahawk land attack missiles. US Navy photo.

Washington, D.C. — Targeted investments in improving weapons and decoys could propel the U.S. submarine fleet to be the underwater answer to anti-access and area-denial (A2/AD) threats, the of the U.S. Navy’s Commander, Submarine Forces (COMSUBFOR) said on Thursday.

Vice Adm. Michael Connor, in contrast to those who talk about responding to the A2/AD threat and finding ways to get out of the asymmetrical cost curve adversaries impose on the U.S. military, said the submarine force is already causing enemies to spend more and is on the cusp of expanding its capabilities.

For example, today’s torpedo has an effective range of 10 miles, he said. But he challenged the research community to develop a propulsion system to bring the torpedoes miles, and one group delivered that. Another group delivered a 200-mile propulsion system.

“So what happens when you have a 100 or 200 mile torpedo? You start thinking, your whole picture of the world changes when you do that,” Connor said at an event hosted by the Center for Strategic and International Studies and the U.S. Naval Institute.

“You stop thinking in terms of what is the bearing and range from my ship to the target, and you start thinking a lot more in terms of geographic coordinates. And the bosses that we work for start thinking of torpedoes as underwater Tomahawks because they can go to the appointed place at the appointed time, they can be potentially redirected and, although it’s our job to get them to the fight, we might easily hand over the terminal homing of one of our torpedoes to somebody else who happens to have better information at the time that that torpedo is going to do the last leg of its journey.”

An intermediate step between today’s “lead bullet” and the 100-mile “gold bullet” is a “silver bullet” idea to have the submarine launch an unmanned aerial vehicle to guide a torpedo over the horizon.

A second development effort is to take the Tomahawk Land Attack Missile (TLAM) and create a “multi-mission weapon” capable of striking land or at-sea targets. The importance is twofold, Connor said. First, submarines do not know what fight they may encounter when they deploy, and having a multi-mission weapon would create efficiencies and a boat better prepared for whatever situation arises.

Secondly, while the warhead the Tomahawk fields may not be as large as the one on a torpedo, “it forces an adversary who thinks that he might have a submarine somewhere within a thousand miles of him, he has to adopt an air defense posture, and therefore he has to carry defensive weapons. And every slot he fills with a defensive weapon, he will not be filling with an offensive weapon.
Vice Adm. Michael Connor, commander of Submarine Forces Atlantic, talks with Cmdr. Michael Meredith, commanding officer of the guided-missile destroyer USS Jason Dunham (DDG-109) on May 21, 2014. US Navy Photo

Vice Adm. Michael Connor, commander of Submarine Forces Atlantic, talks with Cmdr. Michael Meredith, commanding officer of the guided-missile destroyer USS Jason Dunham (DDG-109) on May 21, 2014. US Navy Photo

“Furthermore, he has to maintain air defense radars up, and that helps all of us in a variety of ways to track where he is. And if he wants to do that at a sophisticated level between ships, he ahs to maintain data links up to keep all the ships on the same page, and that provides all kinds of other opportunities for us to do things that are very difficult to defend against.”

Connor said an effort is underway now “to take some of the technology that exists to add, for a small cost, an anti-surface ship capability to our land-attack missiles.” For the small investment, he said the Navy receives a great boost to kinetic capability and the deterrence value of the subs.

Naval Air Systems Command (NAVAIR) conducted a test of a Block IV TLAM striking a moving ship target earlier this year in a test Deputy Secretary of Defense Bob Work called, “a game changing capability for not a lot of cost.”

Connor told USNI News after the event that the area of decoys and deception ought to receive more attention and resources.

“I think we’re not doing enough with decoy and deception, which is absolutely the least expensive way to impose cost on your adversary,” he said.
“And it’s also an area that’s wide open to our creative people – most of what you do, you can do with a very simple platform and then some software.”

Some advancements have been made, including a floating periscope decoy that appears and disappears, much like an adversary might expect a submarine’s periscope to do.

“This is the type of thing we need the creativity to do and implement quickly,” he said during his speech.
“Those types of decoys cost a little less than $3,000. So if I can make people drop million-dollar torpedoes on $3,000-things that look like submarines, we’re on the right side of this asymmetric business. And when you leverage that with the ambiguity of, do I have a submarine or not, and the capability that you must worry about if you have submarines in a certain place, this is how we start getting to this deterrence, conventional deterrence theory, where we can make an adversary realize the cost of going to war at sea with us is severe.”

Connor said the Navy probably would have done some things differently if it had seen the current A2/AD threat coming a little sooner. However, he said the A2/AD threat is coming to the undersea domain, and the United States has a limited window of opportunity to alter how things play out.

If the Navy makes these targeted, small investments in decoys, and the enemy makes a large investment in detecting submarines, “we will put him, after the investment is done, right back in the same position where they are today – ‘I think I might have something, I cant really tell’.”

Connor said he hopes, in that situation, the adversary would drop bombs on the suspected – but false – submarine targets. He said he hopes this happens over and over, until the adversary realizes every attempt to hit an American submarine has failed.

“That is, we think, a key to how we get people who decide to go kinetic to come back off, because they’ll realize it’s a losing proposition, because the whole time they’re doing that we’ll be inflicting significant damage on their forces,” he said.
http://news.usni.org/2015/05/14/comsubf ... 2ad-threat

[Purple]

One thing you should consider when discussing the issue of torpedoes vs carriers is that all the major world powers during the cold war and presumably today stockpile torpedoes with atomic warheads for exactly this purpose.

And the odds are extremely strong that they'll never be used unless the power deploying them is either committed or expecting nuclear warfare, as that's the only realistic response to using an atomic warhead even tactically.

It is telling though that everyone involved figured that they would need one enough to invest in building them.

[Elheru Aran]

One thing you should consider when discussing the issue of torpedoes vs carriers is that all the major world powers during the cold war and presumably today stockpile torpedoes with atomic warheads for exactly this purpose.

And the odds are extremely strong that they'll never be used unless the power deploying them is either committed or expecting nuclear warfare, as that's the only realistic response to using an atomic warhead even tactically.

It is telling though that everyone involved figured that they would need one enough to invest in building them.

They also made nuclear bazookas and land mines. If they could've made nuclear chewing gum, they would've. Skimmer has explained how that wouldn't work now.

[Purple]

They also made nuclear bazookas and land mines. If they could've made nuclear chewing gum, they would've. Skimmer has explained how that wouldn't work now.

My point, a be it a really, really badly articulated one in hindsight is that there is a reason why atomic weapons were seen as everyone by the go to killers of aircraft carriers. And that reason should be obvious to everyone. If you are fighting an aircraft carrier you are in fact fighting its entire escort fleet. All this talk about if a sub could sink a carrier with a torpedo is mostly pointless because if a sub can indeed somehow bypass or rid it self of the carriers escorts it can just unload how ever many torpedoes it takes into the hull. If not, than it needs a cruise missile or atomic torpedo or something similar to clear those out. And that will mission kill the carrier anyway.

[Sea Skimmer]

Basically the nuclear torpedoes were really useful into the mid 1960s. Back then you couldn't get a decent 30 knot homing torpedo, let alone the speed margin you actually needed to hit a fast carrier reasonably, and carrier ASW escorts only had effective sonar and weapons ranges of 10,000 yards or less.

So pretty reasonable to make a straight run shot of a nuke torpedo and the carrier vaporizes with a near direct hit that is an utterly sure kill. Also you might actually get some escorts, though for the protection of the sub such a nuclear torpedo can't have a huge warhead either. T5 was 10kt.

By the mid 1960s and forward though electronics got way better, and torpedo and sonar performance leaped ahead multiple times over. The Soviets very badly lagged on long range wire guided torpedoes because they had very poor computer miniaturization. One result of that was the 65cm wake homers and Soviet wake homing in general being favored as these types of torpedo could search functionally bigger areas then a unassisted passive homer. This made simply carrying more conventional torpedoes a lot more appealing. For the west Mk48/Spearfish/couple other torpedoes pretty much could do everything you'd want.

The 1960s also saw ASW stuff start getting much better for the same reason, computers, and introduction of fast quiet attack submarines and a whole slew of missile technologies. That competed badly for space on both sides submarines, the Soviet reply in part being to simply build huge subs. A US proposal was made around 1974-76 for an insertable nuclear warhead to turn Mk48 torpedoes into nukes at sea. This was not acted on and instead Mk45 was retired without replacement. A project for a simpler Mk47 anti surface only torpedo was also killed.

The Russians came out with some greatly improved wire guided torpedoes in the early 1990s, but generally the submarine fire control computers could only control one or two at a time. The Soviets being stuck at a cloned IBM 360 level computers on a national scale was a pretty serious one. It so completely screwed them to decide to do that.

OF course having a nuclear warhead will always be a serious advantage in making something die if you do hit it, but its not a free item either, nor the torpedo in this case is cheap either. Torpedoes tend to be more expensive then any other tactical weapon for reasons of simple size and the high pressure operating environment at high power. So having a nuclear torpedo is not a tiny budget item if you actually want a decent number around. The US made 600 Mk45 nuclear torpedoes, but that isn't many per sub.

[Sea Skimmer]

Oh and the actual important point, even a 65cm nuclear torpedo won't work in a dead stern chase, submarine starting say 30,000 yards behind a 30 knot target. Tactical nuclear missile has no such problem.