Questions about Submarine abilities

[kato]

what form of guidance does the submarine use to guide the missile to the ship?

None. Inertial guidance to target sector, and the missile is on its own to find the target. Works like with about any type of anti-ship missile. Either that, or other, offboard systems take over guidance (helo, aircraft, satellites...). The sub only acts as launch platform in any case.

If the submarine is going to launch missile attack at a target on land, how would the submarine first be able to detect and identify this target?

Umm, land targets aren't detected and/or identified. You get the fixed coordinate set to fire at, and you fire blind at those coordinates. Broadly speaking.

Also, when a submarine shut down its engine, would it possbile for any platform to detect the submarine?

Leaving aside the wider discussion - yes.

 

[EXSSBN2005]

I have a few questions: when a submarine detects another surface ship and decide to launch anti-ship cruise missile at the surface ship, what form of guidance does the submarine use to guide the missile to the ship?

If the submarine is going to launch missile attack at a target on land, how would the submarine first be able to detect and identify this target?

Also, when a submarine shut down its engine, would it possbile for any platform to detect the submarine? Thanks

Usually going to be handed off to a satilite (my sub didn't carry cruise missiles so I'm going to leave that to others).

I'm guessing that your saying shooting at a moving target if its a fixed target they get you a precise coordinate and you shoot at that (you know where you are and where it is and whats between you, fire down those bearings) for moving targets the planners will usually use a different asset as subs they want to stay hidden until they find a good target that needs a full up cruise missile attack. (They could shoot based on SF troops sitings but I'm not sure they would hit a car for instance[it might be moving thru civilian buildings/area to limit colateral damage], just wait to see where it is going and then plaster the building they go into).

Yes other platforms can detect the submarines but unless it is a another submarine that is quieter the sub with the engines off will know they are there.

As for the rest of the thread, small UAV hadn't been deployed to Ohios as of 2005, we didn't carry SAMs (but that would have been cool to qualify on), Pretty much anytime a sub plays with other ships it will win unless the other ships play dirty (focusing in on your transmitting when you have to tell the controllers of the game where you are right before the kill shot from you is cheating or the surface ships having a box that is larger than the subs hunting box and them staying outside of the box that you can shoot them in, well ya that carrier and most of its group should have been administratively toast).

 

[gf0012-aust]

As for the rest of the thread, small UAV hadn't been deployed to Ohios as of 2005, we didn't carry SAMs (but that would have been cool to qualify on),

USS Florida deployed a UAV as part of Ex Silent Hammer and as a POC for the SSGN conversions..

would have around late 2004

 

[EXSSBN2005]

Ok maybe I should have specified that it was not deployed to my sub (USS Henry M Jackson [SSBN 730]) and we were in PSNS at the time undergoing the start of refueling from about mid 2004 until I got out in June 2005. I was a MM(n) and had other things to keep up on other than the latest news from the time.

 

[gf0012-aust]

Ok maybe I should have specified that it was not deployed to my sub (USS Henry M Jackson [SSBN 730]) and we were in PSNS at the time undergoing the start of refueling from about mid 2004 until I got out in June 2005. I was a MM(n) and had other things to keep up on other than the latest news from the time.

I don't think it was common knowledge even at the time. eg I only knew because I was in Hawai'i at the time and it was part of a discussion specifically about VLS opportunities.

 

[mk25]

none. Inertial guidance to target sector, and the missile is on its own to find the target. Works like with about any type of anti-ship missile. Either that, or other, offboard systems take over guidance (helo, aircraft, satellites...). The sub only acts as launch platform in any case.



umm, land targets aren't detected and/or identified. You get the fixed coordinate set to fire at, and you fire blind at those coordinates. Broadly speaking.




Leaving aside the wider discussion - yes.

so when the missile surfaces out of water, when there is no other systems like satellite, helo, aircraft to guide the missile over the horizon line of sight, in this case how would the missile be able to first "see" the surface ship? Would there be anything inside the missile itself to help it see the target and guide itself to the target? Is that the inertial guidance that you talk about?

If a target on land is fixed and there is no satellite or other aircraft to guide the missile, I assume that the missile is being guided by the inertial guidance, right? In that case, how big would the CEP be for a cruise missile?

My other question is that I thought the diesel-electric submarine is being detected by its noise and if you shut down its engine, the chance of detecting the submarine is really small, right? So what other method that is used to detect a submarine when its engine is shut off?

 

[mk25]

Usually going to be handed off to a satilite (my sub didn't carry cruise missiles so I'm going to leave that to others).

I'm guessing that your saying shooting at a moving target if its a fixed target they get you a precise coordinate and you shoot at that (you know where you are and where it is and whats between you, fire down those bearings) for moving targets the planners will usually use a different asset as subs they want to stay hidden until they find a good target that needs a full up cruise missile attack. (They could shoot based on SF troops sitings but I'm not sure they would hit a car for instance[it might be moving thru civilian buildings/area to limit colateral damage], just wait to see where it is going and then plaster the building they go into).

Yes other platforms can detect the submarines but unless it is a another submarine that is quieter the sub with the engines off will know they are there.

When a submarine launches its missile or torpedo, the sub is also revealing its own location, right? Does the opposing force can pinpoint the exact location of the submarine or just the estimated proximity where the submarine is located?

 

[Waylander]

The INS/GPS he is talking about is guiding the missile into the target box were the missile seeker takes over.
This means the missile uses it's own radar or IR device to identify and attack the target. The same applies to mobile land targets.

If there is no GPS/GLONASS/whatever available missiles use INS to guide themselves.

As I am by no means a naval expert this is simplified.
For example a sub detects a target by active (active sonar, radarmast) or passive (passive sonar, ESM-mast, periscope) means. By doing this it gets the rough target data. Now it fires it's missiles into the target box on a direct line (some missiles are also able to fly by preprogrammed wayoints) and lets the missile do the rest.

Torpedos on the other hand can have some other options. Some of them do not only have to rely on their own active/passive guidance system but are connected to the sub via a cable. This means it's a 2-way datalink. So the sub can stear the torpedo manually up to the attack phase giving them the ability to perform some tricks.

As for detection while fiuring a weapon.
Others here know much more but generally such a question can only answered by saying "it depends..."
Naturally the passive sonar capabilities of thge listening platform are of great importance in this as is how the sub ejects the weapon.

So a very capable listening platform is much more able to precisely locate a loud firing sub and vice versa.

 

[Humming Drone]

A submarine aircraft carrier actually existed. Japanese built I-400 class submarines during WW2. This class of subs could carry 3 planes. Americans studied the subs, by the way.

Today, I don't think it is viable to build a submarine aircraft carrier - these must be monsters in size considering the task. And launching (and more importantly recovering) planes must still be done on the surface, taking away sub's most critical advantages. A job could be done with cruise missiles, which is what Navies have realized some time ago.

 

[kato]

If a target on land is fixed and there is no satellite or other aircraft to guide the missile, I assume that the missile is being guided by the inertial guidance, right?

Most cruise missiles have some sort of target recognition system for the terminal phase.

In the Tomahawk missile for example, this system is called DSMAC, and contains an image of the target taken earlier (usually a computer-generated target image created for this purpose). The system searches for a match to this image and guides the missile to it. Other systems may use e.g. infrared images or radar imagery for the same purpose. Simpler systems may e.g. only use GPS (or a similar system).

This is btw also part of why pretty much no current cruise missile can be used against mobile targets, and why there are specialized systems for such purposes. The "image" would change significantly, and the missile can't find it.

So what other method that is used to detect a submarine when its engine is shut off?

An active sonar ping...

In that case, how big would the CEP be for a cruise missile?

Cruise missiles don't use only INS, but always have some sort of terminal guidance (and often back up INS with GPS or sensor systems like TerCom).

As for CEP using only INS, for ballistic missiles that's usually in the region of 100-200 meters. Depends on range.

 

[Beatmaster]

a few quick questions:

What is the basic weapons layout of a diesel sub and of a nuclear sub?
I understand that there are many variants and types but what is the "norm" layout weapons layout of a standard-average sub? these days?

And are subs (Both nuke and diesels) today still a viable asset as weapons platform, against modern planes and surface warships? (Not talking about intelligence and other nice features a sub has) iam talking pure as a hunter or weapons platform?

Because to my understanding the average frigate/cruiser or surface combatant is pretty much armed to their teeth to fight off subs, so is a average sub still suitable as weapons platform? or should this be left to the surface combatants as i have the idea that frigates/cruisers and destroyers are better suited to do so.

Should the sub in general stick to under-cover and secret Intel missions?

 

[kato]

Layout: 4-6 forward-oriented tubes, typically 12-20 weapons for this in SSKs and twice that in SSNs. VLS on SSNs remains a USN quirk, and is really only used for Tomahawk.
Highly variable load in the tubes (missiles/torpedoes) depending on mission. Loading less than capacity to gain some space is rather the rule these days, especially on smaller SSKs.

With exceptions of course (Seawolf...). Most of what runs around under the water conforms to the above.

 

[My2Cents]

1) Can Submarines launch fixed wing aircraft, or helicopters or UAV's and is there a potential future for submarine launched aircraft? Sort of a underwater carrier?

Many nations experimented with submarines that carried reconnaissance seaplanes up thru WWII, but only the Japanese actually used one for combat (once).

The 1st problem has always been the hanger, which is large and presents a large cross-section to the flow over the hull, and the hanger doors has to be large enough to pass the folded aircraft, which is typically greater than 20’. This are probably the largest pressure hatch ever put on a submarine, and typically restrict the sub’s diving depth to less than 100m, which makes the sub much more vulnerable.

The other problem is that to launch the aircraft you have to surface, open the hanger, assemble the aircraft, fuel and arm it, reseal the hanger (and probably pressure test it, large seals are tricky), and catapult launch it. To recover the aircraft either lands on the ocean (seaplane) and is recovered with a fold away crane, or lands on the deck (VTOL), then is moved back into the defueled and returned to the hanger and the hanger resealed. All this takes time probably over ½ hour per plane, and is only practical in calm seas because of a sub’s low freeboard. That is a long time to stay on the surface in an area which will probably be within range of air patrols. If the sub is forced to dive any planes outside of a sealed hanger (and it is unlikely they will have to reseal the hanger if open) will of course be a total loss. :wah

The sub itself will have to be quite large, to provide room and the necessary deck area, and boat shaped for stability on the surface, which will limit speed and stealth when submerged. It will also need to have a large buoyancy reserve in case the hanger is flooded.

The aircraft will need to be the smallest practical size because of hanger limitations, which in turn limits the aircraft’s performance, and the fact that it will have to be a float-plane or VTOL limits it even more.

2) Can Submarines launch SAM's and have the ability to look from below the water, into the air (radar that can penetrate water?)? Could there be a future to this? Could a submarine come out of the water/ocean and then launch SAM's. Are any nations working on this?

3) Could a submarine be capable of acting as a "hidden" naval SAM site?

There has been some work using blue-green lasers in this area. If a system is ever developed that can penetrate water to survey the air it is likely that it can be reversed to allow aircraft to scan underwater as well. However, it is unlikely that it will be able to view more than a fairly narrow vertical cone above the submarine. Finally, any active system should be easily detectible outside its own detection range, pin-pointing the sub’s location.

Using sensors located on a different platform is possible if the submarine stays at periscope depth with the ESM up, otherwise it is nearly impossible to communicate with a submerged submarine. Likewise missiles can only be launched from shallow depths, and will almost certainly reveal the submarines general location.

But the big problem with using a submerged submarine as an anti-aircraft platform is that the missile load is it’s ONLY defense. As long as the submarine is submerged there can be no ECM, chaff, RAM, CIWS, or other defensive systems deployed. It is a sitting duck for any surviving aircraft with weapons that can attack a submerged vessel. On the surface because of limitations on deployable sensors a submarine is just a very expensive anti-aircraft platform with inferior capabilities compared to a surface vessel. :nutkick

 

[kato]

As long as the submarine is submerged there can be no ECM, chaff, RAM, CIWS, or other defensive systems deployed.

Umm, disagree there. There are several defensive systems that have been under development the last 10 years that a submarine can be equipped with to defend itself against attacks from aircraft (or surface ships, or other submarines), including softkill decoy and jammer systems and actual hardkill systems. Some products in that direction are e.g. Circe/TAU, C303/s, Sea Siren and Sea Spider. IDAS could actually also be seen as a hardkill defense system regarding its intended usage.

 

[Todjaeger]

There has been some work using blue-green lasers in this area. If a system is ever developed that can penetrate water to survey the air it is likely that it can be reversed to allow aircraft to scan underwater as well. However, it is unlikely that it will be able to view more than a fairly narrow vertical cone above the submarine. Finally, any active system should be easily detectible outside its own detection range, pin-pointing the sub’s location.

Using sensors located on a different platform is possible if the submarine stays at periscope depth with the ESM up, otherwise it is nearly impossible to communicate with a submerged submarine. Likewise missiles can only be launched from shallow depths, and will almost certainly reveal the submarines general location.

But the big problem with using a submerged submarine as an anti-aircraft platform is that the missile load is it’s ONLY defense. As long as the submarine is submerged there can be no ECM, chaff, RAM, CIWS, or other defensive systems deployed. It is a sitting duck for any surviving aircraft with weapons that can attack a submerged vessel. On the surface because of limitations on deployable sensors a submarine is just a very expensive anti-aircraft platform with inferior capabilities compared to a surface vessel. :nutkick

Lidar systems already exist. So far they have been used for mapping of shores, nearshore areas, as well as shallow water areas. IIRC there has also been some work on using helibourned lidar systems for mine detection. I would not be at all surprised if work has been done or is being done in terms of ASW applications for airborne lidar, at least for shallow water ASW any way.

As for methods to detect submarines, even when they are 'shutdown'... There are several methods, the first being the passive sonar then active sonar. There is also the possibility of using MAD (Magnetic Anomaly Detector).

Now, one of the first things which would need to be done is to establish (or attempt to anyway) some form of 'search box' and then use active and passive sensors to 'look' as it were at a given area. In terms of search boxes, depending on the locations and times, fixed sensors could provide some additional information. By fixed sensors I am referring to things like SOSUS, or some of the photonic harbour bottom sensors, but these are typically only able to provide a time frame of when contact xx crossed it.

-Cheers

 

[My2Cents]

Umm, disagree there. There are several defensive systems that have been under development the last 10 years that a submarine can be equipped with to defend itself against attacks from aircraft (or surface ships, or other submarines), including softkill decoy and jammer systems and actual hardkill systems. Some products in that direction are e.g. Circe/TAU, C303/s, Sea Siren and Sea Spider. IDAS could actually also be seen as a hardkill defense system regarding its intended usage.

The first 4 are decoy systems for torpedoes. I am not sure how effective they would be in a situation where the submarine would have to be very shallow (<100 ft water depth) against aerial torpedoes deployed at close ranges. At that depth aircraft bombs with delay impact fuses could also be deployed with considerable effect as depth charges.

IDAS is a fiber-optic control missile design for attack against surface targets and low speed and altitude aerial targets (i.e. helicopters), which would indicate speeds less than supersonic. As such it would not pose a major threat against fixed wing aircraft, which may well be faster.

 

[kato]

would have to be very shallow (<100 ft water depth)

IDAS can effectively be launched as long as the water pressure doesn't crush it. This is presumably a bit more than 3 bar. At least in theory it also doesn't have to break surface right above the sub.

against aerial torpedoes deployed at close ranges.

Erm, look up how a Mk46 et al works. It needs to find a target to home in on first once it's in the water. Itself, not preprogrammed by the carrier system. Start Sea Siren once you suspect a torpedo will be dropped at you, and the torpedo may have a problem there.

Also, let's not forget common sense. Pair of ASW helos on patrol, certain distance, when one of them is suddenly hit by an IDAS? Assuming the other is within combat distance (<10 km), it will drop its torpedoes as soon as possible to combat the sub and bail to a safe range/height envelope while calling in the attack. Because the crew knows there's at least three more missiles waiting.

At that depth aircraft bombs with delay impact fuses could also be deployed with considerable effect as depth charges.

Except it's rather unlikely nowadays that a MPA or ASW helo would carry these.

As such it would not pose a major threat against fixed wing aircraft, which may well be faster.

Exactly how many supersonic ASW aircraft are there? High subsonic? The only ASW aircraft that can even approach 75% of the speed of sound (and won't do that on patrol) is the P-8.

 

[radar07]

i don't think that idas will be a big game changer.
first of all a sub commander will try to stay undetected as long as possible. launching a idas will lead to a immediate detection so he will only use it if he is sure that he was already detected. before he launchs the idas he has to track the target to increase the chance of a hit. if the target is a mpa this is a big issue.
and at the end we will see more modern decoy systems on the helos and mpa's.

 

[kato]

and at the end we will see more modern decoy systems on the helos and mpa's.

IDAS is EO-guided via cable. Decoys won't do anything.

 

[radar07]

for this reason i used "modern" in my sentence. ;-)
systems like thales dircm flash blend the seeker. thales itself also says "damaging the sensor elements".
but decoy systems was misleading here, jamming systems would fit more.