Modern Carrier Battle Group..Strategies and Tactics

[Wolverine]

Re: How Do You Sink A Carrier?

No one would really search for a ship with an optical sensor. If one is going to use satellites to try to search for ships, they'd use radar, probably one working in S band, which would be basically immune to any sort of weather/cloud/rain/whatever. Operating from an altitude of some 250 km, search area could be decent enough, close to 500 km in width. Detecting and classifying targets from such distance would not be a problem. Of course, the reason why no one is really using satellites for such missions is cost. Soviets could have hoped for short periods where they'd launch a certain number of satellites and still cover only several parts of the world's ocean. And keeping a heavy satellite in such low orbits lasts a short time, perhaps a few months. Furthermore, its orbit doesnt really allow it a lot of freedom. Sure, one could use thrusters more, but then its life expectancy, as seen in soviet us-a satellites, could drop even more, to mere weeks.

If one would desire a long term near continuous coverage of, say, 1000 km wide swath of ocean, with 30 minute gaps between satellite passes, they'd have to use literally over 330 satellites. Like I said, short term coverage would be possible with fewer satellites, with as little as 6, but then their lifetime would drop dramatically as they'd have to be reorbited with each revolution, and they'd become more or less one time, single mission, surveillance platforms.

Of course they can use E/O satellites to search for ships, especially if you are only searching in a limited area. It's called real time imagery. Don't forget that a carrier is not a ship like other ships. It's shape is large and distinctive and will stick out like a sore thumb, even amongst a sea of oil tankers and cargo ships. We are not talking about demanding the maximum 10 or 15 cm resolution fixed on somebody's backyard from these E/O satellites. We are talking about finding a 330m long, 18,200 square meter target against a conveniently contrasted background (the ocean) in a relatively small stretch of the Western Pacific and South China Sea. Not necessarily a cakewalk, but not necessarily a gargantuan effort either. And once again, there is no need to compare what China would do with their imagery satellites in a Taiwan conflict compared to what the Soviet Union tried to do with theirs during the Cold War. And if E/O satellites cannot be used to locate carriers, why then did they hide beneath clouds during the Cold War? Radarsats are immune and AEW/C are immune. So what were they hiding from?

And I'd like to see what sources you used to conclude that 330 satellites would be needed to cover a 1,000 km "swath" of ocean. What does that even mean by the way? 1,000 square km? 1,000 km width by XXXX km length? Let's not play fast and loose with word choice here. And don't try to use additional argumentation in your next post, just provide the links. We can do our own math.

It also has to be said that taking down a satellite at 250 km is relatively easy feat, though it does offer some theoretically nifty political possibilities for certain countries.

Which people said that? It took the US over a month and almost $60 million to modify the USS Lake Erie and its Aegis system as well one or two SM-3 rounds to be able to detect and intercept the NROL-21 back in 2006. After the test, the ship's Aegis was re-modified with more money spent, back to its previous configuration, suggesting this ability is either not well-supported by Aegis software or expensive to maintain to the extent that the military felt retaining such a convenient capability was not worth the money to preserve.

 

[Totoro]

Re: How Do You Sink A Carrier?

When comparing an EO system at 200 km or so altitude, which has to zoom in considerably to spot a carrier sized target and scan the area while zoomed in, and a radar system which detects such target with basically a single or double move of its array, it should become evident radar platforms will find sea targets faster. Plus there is no issue of clouds or rain obstructing the view. Both platforms, however, suffer from increased sea state and the inherent inability of a LEO satellite to stay in one place. Sure, thrusters help but at a great cost. EO satellite platforms can, however, stay longer on station as they require less power and have a smaller mass. IR signature may help searching for a non moving ship but frankly, a cruising carrier will sooner be spotted by a big, long white trail behind the ship than by the heat signature. When looked at from above, naturally.

Of course both radar satellites and EO satellities can help detect ships, but satellites are just too expensive for most such missions. Most of the time one does not know where one has to search and when. Keeping an area 3.000 by 1.000 km under constant satellite surveillance is extremely costly and so far no country has opted even to try to afford such a feat. Not only does an average LEO satellite take 80-100 minutes to do a revolution, it can not repeat it over the same location without serious use of thrusters (on top of using them to maintain altitude and precise location). If one lets the satellite to go through its revolutions it would take some 100 or more revolutions to get to the repeat point.

Again, if one had to try, radar based satellites would be a more cost effective solution, in my opinion.

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[Engineer]

Re: How Do You Sink A Carrier?

And I'd like to see what sources you used to conclude that 330 satellites would be needed to cover a 1,000 km "swath" of ocean. What does that even mean by the way?

Swath, or swath-width to be more accurate, is the width of the ground swept out by the sensors as the satellite is passing overhead.

What Totoro meant to say is there needs to be 330 satellites to cover the identical area every 30 minutes. I don't know where he got this number from, but this estimate is wrong. There are only 24 hours a day, so if you set up the orbits such that one satellite passes over an area once every 30 minutes, at most you only need 48 satellites.

Now, assuming a more realistic swath-width of 500 km for a radar satellite, a CVBG moving at 30 kts (or over 60 km/h) will still take some 7~8 hours to cover that distance. So, instead of covering the same area every 30 minutes, it can be done every 3.5~4 hours. Now, instead of 48 satellites, you only need 6.

 

[Jeff Head]

Re: How Do You Sink A Carrier?

It took the US over a month and almost $60 million to modify the USS Lake Erie and its Aegis system as well one or two SM-3 rounds to be able to detect and intercept the NROL-21 back in 2006. After the test, the ship's Aegis was re-modified with more money spent, back to its previous configuration, suggesting this ability is either not well-supported by Aegis software or expensive to maintain to the extent that the military felt retaining such a convenient capability was not worth the money to preserve.

That was in 2006. Lots has happened since then.

As of March 2009, the US Navy has converted 15 AEGIS Destroyers and 3 AEGIS Cruisers to operate BMD with SM3...and more are being converted.

Of the 18, six are stationed in Hawaii, five in Japan, five in San Diego, California and two in Norfolk, Virginia.

In 2010, the US plans to begin converting the rest of its AEGIS cruisers to this capability, and in 2011, begin converting many more of its AEGIS DDGs.

The testing has been so successful, and the conversion costs paired down so much, that this has become one of the US Navy's major current initiatives.

 

[Wolverine]

Re: How Do You Sink A Carrier?

Swath, or swath-width to be more accurate, is the width of the ground swept out by the sensors as the satellite is passing overhead.

What Totoro meant to say is there needs to be 330 satellites to cover the identical area every 30 minutes. I don't know where he got this number from, but this estimate is wrong. There are only 24 hours a day, so if you set up the orbits such that one satellite passes over an area once every 30 minutes, at most you only need 48 satellites.

Now, assuming a more realistic swath-width of 500 km for a radar satellite, a CVBG moving at 30 kts (or over 60 km/h) will still take some 7~8 hours to cover that distance. So, instead of covering the same area every 30 minutes, it can be done every 3.5~4 hours. Now, instead of 48 satellites, you only need 6.

Good point.

That was in 2006. Lots has happened since then.

As of March 2009, the US Navy has converted 15 AEGIS Destroyers and 3 AEGIS Cruisers to operate BMD with SM3...and more are being converted.

Of the 18, six are stationed in Hawaii, five in Japan, five in San Diego, California and two in Norfolk, Virginia.

In 2010, the US plans to begin converting the rest of its AEGIS cruisers to this capability, and in 2011, begin converting many more of its AEGIS DDGs.

The testing has been so successful, and the conversion costs paired down so much, that this has become one of the US Navy's major current initiatives.

No, the Aegis and SM-3 was modified in that instance to have an ASAT capability, not the same as BMD, for which the SM-3 was specifically designed, and Lake Erie had already been given BMD by 2001 at the latest because that was when it downed its first target with an SM-3. This means when Aegis was further temporarily modified in 2006 it was to enable it to attack a satellite, a modification which was subsequently REVERSED.

 

[Totoro]

Re: How Do You Sink A Carrier?

330 satellites for a LEO orbit figure comes from the fact that if one just puts a satellite into orbit and lets it fly its path, it will never cover the same revolution two times in a row. Nor will it repeat a revolution every 10 revolutions. The figure is closer to 100 revolutions, which with revolution duration of some 90 minutes, typical for LEO orbits, comes closer to 6 days.

Once again, one of course can FORCE a satellite to repeat a revolution over the same place , over and over again, but that simply isnt done in practice, it uses up fuel way too fast. Instead of a satellite that remains in space for 4 months, one would have a satellite that would remain in space for mere days. Again, that MAY still have its merits for certain high value operations... Soviet US-A satellites moved over 300 km with each revolution.

And for 1000 km wide swath one would, like it was said, need two satellites each covering a 500 km wide area.

It is true that for simple detection, without tracking, gaps between satellite passes could be made bigger, meaning hours instead of 30 minutes. I used the 30 minutes example stemming from the soviet practice, where they hoped to use only a pair of satellites to give enough info to missiles in flight so they could get in the vicinity of the enemy fleet. If one would use the satellites only as an early warning tool, which i agree is quite enough, especially for coastal protection, passing over every 3 hours, some 55 satellites would do it. Again, just two satellites COULD do the same job but they would burn out their fuel in no time.

On another, much wilder, note, engaging carriers with ballistic missiles MAY not require self guidance on the part of the missile. IF there is a continous track of the carrier, which, granted, is by far the biggest issue and most problematic one, not to mention that if one gets to that point, the carrier group is likely to be steaming away from the theater as quickly as possible, one could try to navigate ballistic missiles (note the plural) with cluster munitions (physics doesn't prevent separation at hypersonic speeds; though it could make the even distribution of submunitions harder) close enough to a carrier for a hit.

So, like it was said, one would need a constant track, meaning an airbrne radar not threatened by anything. Note that we skipped hard to achieve steps to even get here. All this assumes no help from the gps and similar systems. If available, they'd make the whole thing much, much easier but lets assume they're not available. First one determines the plane's precise location, preferably by several radar stations (though that means engagement of the carrier cant be made over 850 km away from the coast, if the main tracking radar is there) Alternatively though, Loran based navigation will pinpoint its location to 10-100 m of error even over a few thousand kilometers, the lower value being for the so called eLoran system.

The airborne radar has a precise ID and location, +/- perhaps tens of meters of the carrier, relative to its own location. Absolute location of both platforms is then deduced via radar/loran systems. A salvo of ballistic missiles is fired. The enemy may or may not detect the launch, it really doesn't change much, as the carrier is being tracked and course corrections are sent to the missiles on their way. What it does change is carrier's speed, as if the info about the launch is conveyed asap, the carrier would speed up and increase the area within which it can hide. Entire flight time, averaging 3.5 km/s, for the total horizontal distance of some 1100 km should be around 8 minutes.

THAAD system has a radar that tracks incoming ballistic missiles from 1000 km away. Thats without knowing where theyre coming from and with having to deal with the smaller RCS of the front of the missiles. Using the same tech for tracking the precise position of one's own missiles, being able to use a sharper, much narrower beam for added precision and immunity to jamming (one cant jam if theres no sample to jam, and there wont be one given to the enemy as there will be some 200 km distance of the radar beam direction and the enemy group), plus the radar is looking at the rear of the missile, with its connectors to dropped boosters, thrusters etc, all giving a larger RCS for a better track.

If we assume 1000 km as the farthest point where the missiles in flight can receive the last course correction, along a depressed trajectory with apogee of some 400 km, the missiles will have some additional 300 km, along their ballistic path, to cross before impact. At average reentry speed of 5 km/sec, which is a fairly conservative projection, missiles would fly without a correction for 60 seconds.

A carrier with some 280.000 shp, with 100.000 t displacement, cruising at 10 kt 60 seconds before impact and trying to accelerate as fast as possible, could change its location anywhere within an area of 0.6 square kilometers. The same ship cruising at 20 kt would hide in an 1.3 km squared area. The same ship doing 30 kt would do the same in 2.4 km squared area. In the unlikely event the ship would be doing 40 kt (available shp and given drag simply wont let it) it would hide in the 3.7 km squared area.

One can calculate how many warheads of which size containing how many submunitions of which kind would be needed to cover such areas. 500 by 500 meter area covered with hand grenade sized shrapnel would require some 10 warheads in ideal conditions, though possible navigation errors and shot down missiles might require higher numbers.

IF we lower the last midcourse correction to just 100 km from the target (also around 100 km altitude), while lowering the re entry speed for 30 seconds before impact, during which a 36 kn carrier would hide in an area of some 0.7 km squared, which could be covered by, in theory, 3 but in practice a few more of the mentioned warheads/missiles.

All that would be beneficial as there'd be added errors during reentry, not even the pershingII with its active radar and self guidance could get to under 30m of error, and it had somewhat slower reentry speed.

 

[Delbert]

Re: How Do You Sink A Carrier?

In sinking a carrier. I think DF-21 varriant. (Which is know as carrier killer) would be sufficient.

Or just use a bomber aircraft and load it with an Atomic Bomb (like the one used against Japan) and send it on a suicide mission towards a carrier group.
"That might be the cheapest way"

 

[druid84]

»Ø¸´: How Do You Sink A Carrier?

Well I think we should avoid the ever popular "let's just nuke the carrier" argument, but it seems other then a massive conventional strike, is it really possible to sink a carrier? Or should we say the super carriers the Americans have, what about sinking the other carriers out there, those of the UK, France, Russia, Brazil, Italy, Spain and Thailand.

Being much smaller, shouldn't they be easier to sink, and I imagine the Thai carrier being the easiest if for no other reason then lack of training for the crew. Any thoughts what would be the easiest current in use carrier to sink?

 

[Jeff Head]

Re: How Do You Sink A Carrier?

No, the Aegis and SM-3 was modified in that instance to have an ASAT capability, not the same as BMD, for which the SM-3 was specifically designed, and Lake Erie had already been given BMD by 2001 at the latest because that was when it downed its first target with an SM-3. This means when Aegis was further temporarily modified in 2006 it was to enable it to attack a satellite, a modification which was subsequently REVERSED.

Actually, the successful USS Lake Erie anti-sat shoot was in February of 2008 and proved the concept in a real-life, live-fire excercise against an errant US errant satellites that was about to fall from orbit. The USS Lake Erie fired a SM3 missile that intercepted and destroyed the satellite 247 km above the earth's surface.

The event was tremendously successul and shows that the SM-3 can be successfully modified to perform anti-sat capabilities. It is doubtful that the US simply sat on that proven capability without acting on it. The US Navy now knows exactly how to modify both SM-3 missiles and AEGIS vessels to accomplish that task and that knoweldge has surely not gone to waste.

I would not be surprised at a later date to learn that certain "enhancements" to the AEGIS system and some of the 250 missiles slated for delivery by 2010 (of which most are alreay delvered) do not extend that capability to some vessels. But even if it has not...my guess is they could quickly make the changes in an emergency now that they know how to do so.

 

[Geographer]

Re: How Do You Sink A Carrier?

I presume everyone here is familiar with Tom Clancy's "Red Storm Rising"? I remember it depicted the Soviets as having a devil of a time finding a US carrier battle group in the mid-Atlantic, even after they took over Iceland.

Why can't China rely on the thousands upon thousands of freight shippers and fisherman between China and North America to spot a carrier battle group? Many are Chinese owned and operated, or at least crewed by Chinese who could radio to the world they just past a convoy of American destroyers at XY coordinates and time, going X knots in Y direction. Even if the battle group didn't take the normal shipping lanes there are still deep water trawlers, research vessels, pleasure yachts, cruise ships, and other types of ships out there. They could even twitter it!

The oceans are empty areas like they used to be, it would be very hard to get that many ships across the Pacific without being noticed by someone.