Well since this exercise was aimed at dealing with Chinese SSKs, what do you think?

According to Swedish newspapers, in training exercises-war games- the SSK Gotland (currently leased to the US Navy) has sunk most sophisticated nuclear submarines. But perhaps even more disconcerting, it reportedly sunk largest aircraft carrier in the USN, the U.S.S Ronald Reagan -CVN-76
Officially say:She's really run rings around our carrier groups
The Pentagon said it believes the greatest undersea threat facing the U.S. Navy since the end of the Cold War has arrived. The threat is real. And it has the Navy so concerned that it's turning to Sweden for help. That's because the Swedes have those silent submarines.
The threat involves a new a new class of silent submarines -- subs that the U.S. Navy is having trouble finding under water. In this exclusive investigation, NBC4's Chuck Henry looked into one of those submarines in San Dieg
They came to San Diego because the Navy is worried about this new generation of silent subs.
The Pentagon leased the Gotland for one year, but now has extended the lease for a second year, as they try to learn why this submarine so difficult to find underwater.
When the Gotland wants to be silent and undetectable, especially along coastal waters, there's not a place it can't go. And that's one of the reasons it's here.
Since last summer the Navy has spent months playing a game of cat and mouse with the Gotland off San Diego, and time after time the Swedish sub has eluded its pursuers.
Although this emerging undersea threat is a top priority for the U.S. Navy, the U.S. is committed to its nuclear submarine force, and has no plans to develop subs like the Gotland.
The Navy says it just wants to know how to detect and kill them.
3 submarines Gotland Class (Type A19) , and 2 submarines of the Vastergotlnd Class (Type A17) are currently in service in the Swedish Navy.all of them with a (Striling) air-independent propulsion system (AIP), which extends their endurance from a few days to several weeks.

That is typically how the USN does things. Train hard so when the real thing comes along, you know how to handle things. It looks like Gotland is the the subject experiment on how to prosecute ultra quite long endurance SSKs.

The Gotland class is several years ahead of what the PLAN can field. IF the USN can prosecute this sub on a routine bases, the Kilos and other SSKs will not be a problem.

Also, during exercises USN carrier follow a predetermined racetrack pattern. Allied SSK's who claimed to have sink the carrier know where and when the carrier will be at a given point due to the pattern. This information allows them the time to approach the area quitely (at 5 knots) and wait for the carrier to arrive. Since this is a training exercise, the Sub captain and crew get to train on how to approach a carrier and fire a torpedo. In a real war time scenario, the sub captain will not know ahead of time where and when the carrier will be, which makes his job (being limited to 5-10 knots cruising speed) increase in difficulty by several magnitudes

The US conducts exercises with its allies and do it several times a year, always taking red forces (opposing force) . There's no point for US to take blue, because they are the ones acting as the "training aid."

Here is a quote from another board about the SSK and their effectiveness.

(1) A state of the art SSK has a maximum endurance of about 400km at about 4 knots on its batteries. You don't get anywhere at 4 knots and you certainly are not going to be very successful chasing your quarry at that speed. You also do not typically run your batteries 95% flat before a recharge. Rather you tend to do it at conventient times when you don't think there is anyone around to find and kill you. When you surface to run your diesels you have very little stealthy on your side. You are noisy and at periscope depth. In fact, every other thing aside, running fast and near the surface is doubly bad acoustically because your screw cavitate like hell near the surface whereas at depth the water pressures migates the formation of vaccum pockets on the trailing edged of your screw reducing or eliminating cavitation. Radars can find your snorkel, SSNs and ASW ships can hear your from a long way off and aircrafts can literally see you at that depth. You are basically exposing yourself!

(2) There is always the option of AIPs. The problem is that firstly AIPs, probably with exception of the Fuel Cell, is not as silent as motors on batteries. The sterling is a reciprocating piston engine running of separately heated working gas. The Close cycle diesel is exactly that a diesel engine running on diesel fuel, oxygen and part of its recycled exhaust. The MESMA is a steam turbine running on the products of alcohol-oxygen combustion. They all make more noise than a battery does and they all have exhausts to get rid of. The worst thing howeveris that power density is in usually horrible enough that cruise speed on AIP is no better than 5-6 knots and there is every little power left over to recharge the batteries in a timely manner. The Fuel Cell which is the quietest AIP setup also happens to have the worst energy density by a long shot... large PEM stacks, large LOX tanks and huge LH2 tanks, all for less energy yield than the combustion type AIPs. In the end what it means is that AIP boats usually transit or maneuver tactically by running their diesels and running on the surface or at snorkel depth to get close to their quary. In a real war with a massive navy like the USN, a lot of them will be picked off while doing this by ASW aircraft and a forward screen of SSNs.

(3) The other fallacy is that batteries and electric motor equals total silence. This is nonsense. In fact, it is frequently not flow noise and propeller noise which shows up most prominently on a sonar system when an SSK is picked up. It is frequently the inverter buzz from the switching inverters which the SSK uses to convert its DC battery power to AC current to run its motors with. Just about all high power motors are AC induction motors.

(4) The last thing when cosidering using diesels against a major surface action group is that all the silencing advantage is useless against active sonar which is routinely employed on ASW helos and once they catch a glimpse of you, an SSK has neither the speed on the endurance to slip away. Once found you are usually dead meat.

This is very intresting. A few months ago the USN was bragging about how it was training so well against the HMS Gotland. I think the information you are refering to occuried in 2005. In 2006 CVN-76 has been deployed to WESPAC and the Gulf region. And has only recently emerged from it's San Diego home to start training in prepration for another deployment.

I'm curious. How old is this information? And can you provide a link about thse wargames? I'm pretty sure this training occured with CVN-76 in 2005.

And remember SSK's are generally designed for littorial waters. CVN's are for Blue water ops.

Wait there's more. There is great clamor in the US by liberal enviormentlist trying to hinder the USN ablity to train with sonar in US terriorial waters. Friggin' goofballs!

Navy gets input on sonar range in first of six public meetings
By KATE WILTROUT, The Virginian-Pilot
© October 24, 2006

CHESAPEAKE — A year ago, when the Navy asked for public input on its use of sonar, it got an earful – and then some.

More than 40,000 comments came flooding into Norfolk computers and mailboxes, most opposed to Navy plans to establish a sonar training range off the coast of North Carolina.

Last month, the Navy announced plans to study how its sonar use affects the ocean’s creatures and habitats, and what it might do differently to reduce the threat to mammals, fish and the economy. The results could change the way the sea service trains its sonar technicians, practices hunting submarines and conducts exercises.

Norfolk resident Gina Coelho, who rearranged her schedule to attend the meeting, had expected to see more people Monday night. About 30 had passed through the open house within two hours.

Coelho, who works as an environmental scientist, said she follows reports of stranded whales and dolphins. In some cases, there seems to be a clear link to nearby Navy operations, she said. Other times, scientists seem befuddled by the events.

She said she’s glad the Navy will take a hard look at its sonar practices and use the latest scientific research to determine how it could be a better steward of the environment.

Coelho also said she supports the Navy’s mission: “But I think there’s a way to accomplish the mission and do it responsibly.”

Jene Nissen, project manager for the environmental study, said the Navy is looking at specific areas within the 300-mile economic exclusion zone where the vast majority of sonar training occurs. The study will examine whether it’s better to conduct most sonar training in a number of spots along the coast, perhaps changing them to avoid peak mammal migration. Or they might find, Nissen said, that it’s better to spread the impacts over a large area – the way the Navy now trains.

Capt. Chuck Sitarski, the chief of staff for anti-submarine warfare in the Western Atlantic, said technology has made it harder to detect diesel submarines. Ship crews need to practice clearing threats from the vicinity of an aircraft carrier – “sanitizing the water,” Sitarski called it.

The Navy will also study sonar used in sonobuoys that track traffic and in “dipping arrays” that mine-hunting helicopters drag through the water

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IDonT said:

The Gotland class is several years ahead of what the PLAN can field. IF the USN can prosecute this sub on a routine bases, the Kilos and other SSKs will not be a problem.

Also, during exercises USN carrier follow a predetermined racetrack pattern. Allied SSK's who claimed to have sink the carrier know where and when the carrier will be at a given point due to the pattern. This information allows them the time to approach the area quitely (at 5 knots) and wait for the carrier to arrive. Since this is a training exercise, the Sub captain and crew get to train on how to approach a carrier and fire a torpedo. In a real war time scenario, the sub captain will not know ahead of time where and when the carrier will be, which makes his job (being limited to 5-10 knots cruising speed) increase in difficulty by several magnitudes

Here is a quote from another board about the SSK and their effectiveness.

(1) A state of the art SSK has a maximum endurance of about 400km at about 4 knots on its batteries. You don't get anywhere at 4 knots and you certainly are not going to be very successful chasing your quarry at that speed. You also do not typically run your batteries 95% flat before a recharge. Rather you tend to do it at conventient times when you don't think there is anyone around to find and kill you. When you surface to run your diesels you have very little stealthy on your side. You are noisy and at periscope depth. In fact, every other thing aside, running fast and near the surface is doubly bad acoustically because your screw cavitate like hell near the surface whereas at depth the water pressures migates the formation of vaccum pockets on the trailing edged of your screw reducing or eliminating cavitation. Radars can find your snorkel, SSNs and ASW ships can hear your from a long way off and aircrafts can literally see you at that depth. You are basically exposing yourself!

(2) There is always the option of AIPs. The problem is that firstly AIPs, probably with exception of the Fuel Cell, is not as silent as motors on batteries. The sterling is a reciprocating piston engine running of separately heated working gas. The Close cycle diesel is exactly that a diesel engine running on diesel fuel, oxygen and part of its recycled exhaust. The MESMA is a steam turbine running on the products of alcohol-oxygen combustion. They all make more noise than a battery does and they all have exhausts to get rid of. The worst thing howeveris that power density is in usually horrible enough that cruise speed on AIP is no better than 5-6 knots and there is every little power left over to recharge the batteries in a timely manner. The Fuel Cell which is the quietest AIP setup also happens to have the worst energy density by a long shot... large PEM stacks, large LOX tanks and huge LH2 tanks, all for less energy yield than the combustion type AIPs. In the end what it means is that AIP boats usually transit or maneuver tactically by running their diesels and running on the surface or at snorkel depth to get close to their quary. In a real war with a massive navy like the USN, a lot of them will be picked off while doing this by ASW aircraft and a forward screen of SSNs.

(3) The other fallacy is that batteries and electric motor equals total silence. This is nonsense. In fact, it is frequently not flow noise and propeller noise which shows up most prominently on a sonar system when an SSK is picked up. It is frequently the inverter buzz from the switching inverters which the SSK uses to convert its DC battery power to AC current to run its motors with. Just about all high power motors are AC induction motors.

(4) The last thing when cosidering using diesels against a major surface action group is that all the silencing advantage is useless against active sonar which is routinely employed on ASW helos and once they catch a glimpse of you, an SSK has neither the speed on the endurance to slip away. Once found you are usually dead meat.

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IDONT, you are spot on with these comments. See my below comments to popeye.

bd popeye said:

This is very intresting. A few months ago the USN was bragging about how it was training so well against the HMS Gotland. I think the information you are refering to occuried in 2005. In 2006 CVN-76 has been deployed to WESPAC and the Gulf region. And has only recently emerged from it's San Diego home to start training in prepration for another deployment.

I'm curious. How old is this information? And can you provide a link about thse wargames? I'm pretty sure this training occured with CVN-76 in 2005.

And remember SSK's are generally designed for littorial waters. CVN's are for Blue water ops.

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Popeye, I believe that the training exercises are just that...training. In most cases there are very set parameters and within those parameters, known to the adeversary, the exercises are conducted. Actual wartime conditions would be far different. We saw the same thing happen with air force exercises.

I will say this...in wartime out in the blue water, a carrier will be tansiting in a buttoned up condition, and will be moving significantly faster than a diesel electric can maintain...and if they tried, they would be heard and prosecuted. So, they will depend on intellignece knowing when and where a carrier is going to be and waiting there with limited endurance for the carrier to pass within range...which is a wild shot in the blue waters.

I will admnit that the DEs, particularly the AIPs are VERY dangerous in the litoral waters, or if they happen to have excellent intelligence and can lay in wait.

I'm curious. How old is this information? And can you provide a link about thse wargames? I'm pretty sure this training occured with CVN-76 in 2005.

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I got this from a thread started in Key Aviation. Here's the link to the San Diego TV station website that had the story.



Here's a story I found that mentions the exercise at the end of the article:



Here's an article that says the US Navy detected the Gotland.

IDonT said:

The last thing when cosidering using diesels against a major surface action group is that all the silencing advantage is useless against active sonar which is routinely employed on ASW helos and once they catch a glimpse of you, an SSK has neither the speed on the endurance to slip away. Once found you are usually dead meat.

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The Kilos already have and new follow-on subs offered for export will most probably have surface to air missiles, so those helos could be dead meat also! And you don't need to chase carriers- that's what long range cruise missiles are for!

The The 877EKM-type submarine's hull is covered with sound damping tiles, further reducing noise. It is equipped with six modified SA-N-8 "Needle"-model anti-aircraft missiles, and an MVU-110EM automatic digital command and control system. It can track five targets concurrently, and this class of submarine is generally considered to be extremely quiet.
The 636 type [has] 24 AM-1 underwater mines or eight SA-N-5 "Arrow" standby anti-aircraft missiles.

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Re: Well since this exercise was aimed at dealing with Chinese SSKs, what do you thin

BLUEJACKET said:

The Kilos already have and new follow-on subs offered for export will most probably have surface to air missiles, so those helos could be dead meat also! And you don't need to chase carriers- that's what long range cruise missiles are for!

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Let me explain to you how ASW works and why your answer doesn't work.

1.) Detection and localization are the first objective of ASW, with destruction if possible. This process is conducted by units with endurance and potency: maritime patrol aircraft (P-3) or towed-array equipped surface (FFG or DDG). The air unit typically has magnetic anomaly detection (MAD) as well as sonobuoys to aid such work.

2.) Once the SSK has been localized, where a hostile submarine has been localized to a sufficiently small area to allow an attack with some chance of success, helicopter ASW assets (with dipping sonar, MAD or sonobuoys) are rushed into the area to begin prosecuting it. This is made easier if one is prosecuting an SSK, just plot a 5 knot radius from the probable and begin a standard search pattern. Remember, AIP SSK are SLOW and lack endurance. Sonobouys are dropped (both pasive and active) and dipping sonar is lowered. At this point, the SSK has no idea if it has been localized until a distinctive ping of an active sonar bounces off its hull. At this point it is dead, because a second helo will drop a torpedo on it. With its slow speed, it cannot move fast enough to run away.

3.) The SSK will not have time to go to periscope depth to detect, acquire, and track the helo for it to fire its AAW missiles once pinged by the active sonar. Going to periscope depth takes time (unless you do an emergency blow - which would light you up to every sonar in the area) and makes you more detectable. The torpedo will get you before you even surfaced.

4.) Anechoic tiles are rubber or Sorbothane-like tiles containing thousands of tiny voids, applied to the outer hulls of military ships and submarines, as well as anechoic chambers. They absorb the sonar sound waves of active sonar, reducing and distorting the return signal thereby reducing its effective range. This reduces the range of active sonar by reducing the return signal, it is NOT a stealth at sea. At typical ranges that an SSK is likely prosecuted (5 mile radius) and the littorals no amount of tiles will hide you.

5.) Long range cruise missiles lauched from Subs need third party guidance in order to hit a moving target such as a ship. This problem is compounded the further the sub is from its target. The Soviet Oscar II SSGN uses a complicated system where Bear Recon planes in conjucntion with ocean reconnassance Satellites will feed information to the Oscar. However, communications has always been a problem with subs compared to ships. In order for the Oscar to received this data it has to be a periscope depth. So you need some sort of communication system to tell your Sub to go to periscope depth when the carrier is detected, this also assumes that it is within range of its missiles. This takes time, by the time your ready to fire, the target will no longer be there.

Re: Well since this exercise was aimed at dealing with Chinese SSKs, what do you thin

BLUEJACKET said:

The Kilos already have and new follow-on subs offered for export will most probably have surface to air missiles, so those helos could be dead meat also! And you don't need to chase carriers- that's what long range cruise missiles are for!

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Any submarine that uses any kind of surface to air missile will have to be surfaced. In effect, they are already dead. If your ASW component has a diesel contact localized, the point here is moot. The Kilo is toast.

As far as long range cruise missiles, Kilos and other diesels don't carry enough to be truly effective against a well defended group. And you've just given the group a datum to search and prosecute.

Re: Well since this exercise was aimed at dealing with Chinese SSKs, what do you thin

Sea Dog said:

Any submarine that uses any kind of surface to air missile will have to be surfaced. In effect, they are already dead. If your ASW component has a diesel contact localized, the point here is moot. The Kilo is toast.

As far as long range cruise missiles, Kilos and other diesels don't carry enough to be truly effective against a well defended group. And you've just given the group a datum to search and prosecute.

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In the littorals, the distances are shorter plus there are enemy land based aircraft & cruise missiles in addition to submarines & surface ships!

Re: Well since this exercise was aimed at dealing with Chinese SSKs, what do you thin

BLUEJACKET said:

In the littorals, the distances are shorter plus there are enemy land based aircraft & cruise missiles in addition to submarines & surface ships!

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I wouldn't count on it. Especially if there is an effective strike component associated with the BG. But what does the above here have to do with Kilo's using SAM's? If a Kilo in the littorals are surfacing and using SAM's, it's dead. The conditions or circumstances are of no importance. And that is truly one of the most limiting factors in being a diesel crew. Once detected, your chances of survival are virtually nil. You simply don't have the speed or endurance to effectively escape.