CV-17 Shandong (002 carrier) Thread I ...News, Views and operations

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by78

General
Some grainy satellite photos of Shandong's current trial run...

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Insignius

Junior Member
Funny how people still claim that "you cannot find carrier groups with satellites" on the open seas.

Ofc, only Chinese satellites cant, western satellites are god-like!!11
 

asif iqbal

Lieutenant General
Funny how people still claim that "you cannot find carrier groups with satellites" on the open seas.

Ofc, only Chinese satellites cant, western satellites are god-like!!11

No that is not true I disagree

a snap shot of one place and time does not equate to 24/7 365 surveillance

if you want to track a carrier using satellites you need a whole constellation of them dedicated to just one thing, tracking carriers and thats just practical

if what you said was true no one would building carriers
 

subotai1

Junior Member
Registered Member
No that is not true I disagree

a snap shot of one place and time does not equate to 24/7 365 surveillance

if you want to track a carrier using satellites you need a whole constellation of them dedicated to just one thing, tracking carriers and thats just practical

You are making the assumption that a satellite needs to track (actively follow) something to know where it is. That is not the case. With Machine Learning all you need is a series of consecutive images of the same place or places that boundary each other. This is not hard to do. With even non spy satellites, like Landsat, they are capturing 500+ images at 185km2 per day. With even the first Landsat, that resolution (pixel size) was at least 30m2. With a 330m long carrier, that's 11 pixels just for the length. That's easy to spot, even for the human eyeball and using 1970's imagery capabilities. Modern Spy Satellite capabilities are far better.

Either way, all you need to do is train an ML algorithm to recognize certain classes of ships and train another to watch areas of the ocean (just their repeated images) and the sequence of images and you have the ability to track ships (or anything else). And this is just visual imagery. Throw in SIGINT, LIDAR, IR, Heat Signatures and the rest and yeah, tracking those carriers is trivial.
 

plawolf

Lieutenant General
No that is not true I disagree

a snap shot of one place and time does not equate to 24/7 365 surveillance

if you want to track a carrier using satellites you need a whole constellation of them dedicated to just one thing, tracking carriers and thats just practical

if what you said was true no one would building carriers

Why would China need 24/7 365 satellite surveillance?

The key limitation/difficulties of using satellites for targeting are:

1) field of view vs resolution - the smaller the field of view, the better the resolution. But searching a large body of water with a small search box equals low probability of successful detection.

2) your kill chain vs time on target. Satellites typically only have LoS for a few minutes, which is not enough time to mount a conventional strike package.

However, there are very China-specific factors that make both those difficulties significantly less challenging.

First of all, China’s goal is not to scour the world’s oceans hunting USN carriers. In the event of open conflict, they just need to keep USN carriers a certain distance from the mainland so they cannot mount effective strikes against Chinese targets.

That dramatically reduces the body of water Chinese satellites need to look in.

What more, that body of water is very close to the mainland, and so would allow them to bring all sorts of other detection assets into play, like OTH radars; AWACS, drones and the like. So China could use additional sensors to help them direct their recon satellites to look at areas of interest instead of just systematic scanning.

In addition, if China and the US ever actual come to blows, all existing rules go out the window.

China could simply declare all the waters within the first and second island chains as open conflict zones, but set up safe passage highways for all civilian and neutral shipping to use (which would be easily and heavily monitored by Chinese coast guard ships).

Anything sailing outside of those safe zones will be assumed as hostile to China, and engaged without further warning.

That will effectively clear the board, (especially if China sinks a few ships to show they are not messing around) and pretty much eliminate all civilian and neutral maritime traffic from the defined conflict zones.

What that does is allow Chinese satellites to use the maximum possible search boxes to scan to waters for anything big enough to be a Burke or carrier, and reduce the number of hits to a small enough size to allow Chinese satellites to automatically take snapshots of any hits at higher resolution without disrupting their normal search pattern.

The coding for such a task is pretty elementary stuff, and I am just using an extreme example to illusate just how easy China can make things for themselves.

With the advances China has been making in complex image recognition software, as is evidenced with its proliferating use (Chinese hotels even use facial recognition these days, and have been for years). They can easily add in automated checks to weed out non-warships.

All of this will reduce the number of hits to a small enough number that a few human analysts could check all of them in real time.

As soon as a carrier is detected, the race is on to get to the end of the kill chain before they loose LoS with the satellite.

Again, China has the unique advantage of AShBMs, which can reduce the missile flight time to mere minutes. With real time image processing and human verification; and Chinese rocket forces on a hair trigger just waiting for coordinates, the entire kill chain could be compressed to be only a minute or two longer than the flight time of an AShBM fairly easily.

They can compress that further to be mere seconds after detection if their software is up to scratch to provide high probability matches automatically. In which case human independent verification can be cut-out and the computer can upload target coordinates to launch vehicles directly.

But they should not need to take that risk, since they have the option of going into added time with satellites if needed.

If a Chinese satellite has indeed detected an enemy carrier battlegroup within AShBM range of the mainland, China would gladly sacrifice that satellite, and several more besides if that is what is needed.

As such, Chinese recon satellites can and will use up their entire service lives’ fuel supply if needed to remain on station longer and/or get on station quicker to provide continuous imaging support for as long as possible the AShBM could reasonably need to complete its kill chain.
 

james smith esq

Senior Member
Registered Member
[...]First of all, China’s goal is not to scour the world’s oceans hunting USN carriers. In the event of open conflict, they just need to keep USN carriers a certain distance from the mainland so they cannot mount effective strikes against Chinese targets.[...]

What range do you surmise that to be?
I'm anticipating 1200 - 1600 km.
 

Hendrik_2000

Lieutenant General
You are making the assumption that a satellite needs to track (actively follow) something to know where it is. That is not the case. With Machine Learning all you need is a series of consecutive images of the same place or places that boundary each other. This is not hard to do. With even non spy satellites, like Landsat, they are capturing 500+ images at 185km2 per day. With even the first Landsat, that resolution (pixel size) was at least 30m2. With a 330m long carrier, that's 11 pixels just for the length. That's easy to spot, even for the human eyeball and using 1970's imagery capabilities. Modern Spy Satellite capabilities are far better.

Either way, all you need to do is train an ML algorithm to recognize certain classes of ships and train another to watch areas of the ocean (just their repeated images) and the sequence of images and you have the ability to track ships (or anything else). And this is just visual imagery. Throw in SIGINT, LIDAR, IR, Heat Signatures and the rest and yeah, tracking those carriers is trivial.

Exactly They can weed out civilian ship by filtering it out using AIS Automatic ship identification system
Every civilian ship carry transponder with them to avoid collision That is insurance,international maritime body requirement Military ship does not carry transponder for the obvious reason
The typical carrier outline is very distinct Plus it emit all kind of radio and electromagnetic signal
Then you have CAP necessitating plane take off and landing all the time So it has distinct signature

By now China has 30 or 40 Yaogan, Shijian and other specialized satellite orbiting the earth Plus more than 130 dual use satellite that can be marshaled to help find the carrier

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A marine traffic coordinator using AIS and
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to manage vessel traffic.
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An AIS-equipped system on board a ship presents the bearing and distance of nearby vessels in a radar-like display format.
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A graphical display of AIS data on board a ship.
The automatic identification system (AIS) is an automatic tracking system that uses
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on ships and is used by
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(VTS). When satellites are used to detect AIS signatures, the term Satellite-AIS (S-AIS) is used. AIS information supplements
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, which continues to be the primary method of collision avoidance for water transport.[
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]

Information provided by AIS equipment, such as unique identification,
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,
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, and speed, can be displayed on a screen or an
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. AIS is intended to assist a vessel's
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officers and allow
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authorities to track and monitor vessel movements. AIS integrates a
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transceiver with a positioning system such as a
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receiver, with other electronic
navigation sensors, such as a
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or
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. Vessels fitted with AIS transceivers can be tracked by AIS base stations located along coast lines or, when out of range of terrestrial networks, through a growing number of satellites that are fitted with special AIS receivers which are capable of deconflicting a large number of signatures.

The
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's
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requires AIS to be fitted aboard international voyaging ships with 300 or more
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, and all passenger ships regardless of size.
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For a variety of reasons, ships can turn off their AIS transponders.
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plawolf

Lieutenant General
What range do you surmise that to be?
I'm anticipating 1200 - 1600 km.

Depends on the scenario of the conflict and what opfor does.

But in general, the above range is a little short in my view, as even at 1600km, it would still allow USN strike aircraft to mount high intensty, sustained air launched stand-off missile attacks.

That is why China is developing longer ranges AShBMs like the DF26, and there are rumours of even longer range stuff being worked on.

I think rather than an absolute barrier, Chinese A2AD strategy would be to create increasingly dangerous threat bands for hostile naval forces, making it more and more risky the closer they try to get to the mainland.

So with the likes of the DF26, you are probably looking at a threat range of maybe 4000km. But Chinese detection chances would not be at their best at such ranges.

If an enemy does not want to risk their surface ships, they will probably have to stay 4000km+ away and take pot shots with ship launched cruise missiles. That would suit China just fine since such attacks lacks the intensity to have much chance of getting through Chinese defences to do much serious damage, and also lacks the persistent to be of much serious threat.

If the enemy comes within 4000km, they are putting themselves at risk, and at 1200-1600km, they can probably expect to be engaged by Chinese AShBMs. If not on the way in, they will be after they launch their first air attack and massively narrows down the possible places the Chinese need to look. At which point AShBMs will probably be flying as soon as they can input the co-ordinates after detection.
 
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