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[Tetrach]

Okay thanks you.

Isn't range also determined by directivity ? The main lobe's size surely affects such performances. By having more superposed signals you will result in a better receive gain.

Also I'm quite interested in the SAMPSON. It is considered that each panel is composed of +2000 radiating elements. How is this possible, considering the Type 364 has only around 1250 elements per side for a total of +5000 T/R modules, while having bigger panels ? Considering they operate at the same frequency and as such theirs modules should have the same size, the number of T/R modules should be proportionnal to the size of a panel.

 

[Tam]

Okay thanks you.

Isn't range also determined by directivity ? The main lobe's size surely affects such performances. By having more superposed signals you will result in a better receive gain.

Yes it is, I prefer to call it transmit gain. Receive gain can also be referred to as antenna aperture.

I forgot to mention that of course, radar cross section affects range, and also note that radar cross section changes with frequency. Something that can have a very low RCS in one frequency can be higher on another.

Also I'm quite interested in the SAMPSON. It is considered that each panel is composed of +2000 radiating elements. How is this possible, considering the Type 364 has only around 1250 elements per side for a total of +5000 T/R modules, while having bigger panels ? Considering they operate at the same frequency and as such theirs modules should have the same size, the number of T/R modules should be proportionnal to the size of a panel.

Don't refer to it as Type 364, its Type 346. Type 364 is the radar encased on a globular radome on top of the mast, not the four panels. This particular radar, set on top of the mast, gets a high view of the ocean and farther radar horizon, and is used to spot and track sea skimmers and other low flying targets. It also cues the CIWS and the HQ-10 launchers towards the threat bearing.




Actually, Type 346 has over 5,000 elements per panel, but also note that its using a QTRM, which means there are four T/Rs per module. Go back to one of my previous post. So there are 1250 modules, each module a QTRM, so about 5,000 T/Rs. QTRMs is a great way to save money on AESAs. Given the size of each panel, about 5,000 or over S-band T/R elements is about right. The whole ship should have about 20,000+ T/R elements, and this is going to be very expensive if each element has its own LNA (low noise amp). So in a QTRM, four T/R elements share the same LNA and A/D converter as a single module. So over 20,000 T/R elements, 5000 modules.

Aside from the poor English, this statement describes a QTRM, by someone who is writing this in Chinese and having it poorly translated in Bing or Google Translate then cleaned up with editing.

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"Instead, the design team took an approach similar to that of British

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and Israeli

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APARs by group four transceivers into a transmitting/receiving (T/R) module with 100W peak power,"

"Type 346 inherits the design feature of the prototype of grouping four transceivers into a 100W peak power T/R module with its own power source.

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"

Here is an example of an X-band QTRM.



India's Uttams AESA radar uses QTRMs with radiator shaped antennas on the elements.

 

[Lethe]

I don't follow the construction process of new warships in nearly as much detail as some posters here do, but if the numbers from Chinese Wikipedia are to be believed (26 052Ds and 8 055s identified) then, given that all those units should be commissioned by 2025, they suggest a fleet size in 2025 of 40 to 52 destroyers. The lower bound requires everything pre-052C to have been decommissioned by 2025, which seems unlikely, while the upper requires the final pair of 051s (and everything newer) to remain in service. While it is possible that the pace of retirements could accelerate considerably going forward, I do think that the upper end of the range is more likely than the lower, with a midrange estimate of perhaps 48 destroyers in 2025, consisting of the 055s and 052Ds, 052Cs, Sovs/052Bs, 051Cs and perhaps the 051B.

Of course this is just regurgitating publicly available information, but I found it rather interesting when one considers that it was only a few years ago that mainstream projections of China's future naval strength were far more modest, with destroyer numbers in the 30s commonly cited. How quickly things can change, even when one is vaguely paying attention.

 

[Bhurki]

I don't follow the construction process of new warships in nearly as much detail as some posters here do, but if the numbers from Chinese Wikipedia are to be believed (26 052Ds and 8 055s identified) then, given that all those units should be commissioned by 2025, they suggest a fleet size in 2025 of 40 to 52 destroyers. The lower bound requires everything pre-052C to have been decommissioned by 2025, which seems unlikely, while the upper requires the final pair of 051s (and everything newer) to remain in service. While it is possible that the pace of retirements could accelerate considerably going forward, I do think that the upper end of the range is more likely than the lower, with a midrange estimate of perhaps 48 destroyers in 2025, consisting of the 055s and 052Ds, 052Cs, Sovs/052Bs, 051Cs and perhaps the 051B.

Of course this is just regurgitating publicly available information, but I found it rather interesting when one considers that it was only a few years ago that mainstream projections of China's future naval strength were far more modest, with destroyer numbers in the 30s commonly cited. How quickly things can change, even when one is vaguely paying attention.

Destroyer production currently stands at about 4 per annum (2.5 for 052d and 1.5 for 055). Considering a average hull life of 30 years, that means PLAN can field more than 100 destoyers even after accounting for decommissioning of older combatants.
Its obviously in the spurt phase now and may not continue at the same speed in the future, but starting 2030, PLAN would be able to field a force of atleast 60+ modern destroyers ( under 25 years of hull age) on a sustainable basis even after including MLU in the loop.

 

[Deino]

Just a strange question ... what do you think about this post??

Type 003/004? start construction in Dalian.

Source:

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Pardon, but I cannot see a certain part that could fit to a 003/004 carrier? .... even if I don't know what these strange long structures are, I don't remember similar ones already to be seen.

Or did I miss a certain part?

 

[Mirabo]

Just a strange question ... what do you think about this post??

Pardon, but I cannot see a certain part that could fit to a 003/004 carrier? .... even if I don't know what these strange long structures are, I don't remember similar ones already to be seen.

Or did I miss a certain part?

I think it's too early to say.

The OP's explanation is that the support struts you see in the middle of the picture are the same struts that were used to support the flight deck overhang of 002, before it was welded onto the main hull component. Given that Dalian will likely not employ large module construction (different from Jiangnan), this is a plausible theory.

But this explanation is still rather weak. We will probably hear something more concrete in a few months time.

 

[Xizor]

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Is there some kind of informal agreement between the world powers in limiting the number of nuclear delivery platforms like SSBNs? I've noticed that the French and British limit themselves at the 4+4 or 4+6 SSBN and SSN. I know that Russia and US might have a formal "understanding" . Both seems to limit it at 12 to 14. US can choose to build more.

My doubt is whether China is limited by such agreements or understandings. How much SSBN China can build? What if China tries to match US ? Any backstage dealings regarding the current buildup? Has all this got anything to do with the trade relationship between the two countries?

 

[Lethe]

There are no formal or informal understandings regarding SSBN numbers.

 

[Biscuits]

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Is there some kind of informal agreement between the world powers in limiting the number of nuclear delivery platforms like SSBNs? I've noticed that the French and British limit themselves at the 4+4 or 4+6 SSBN and SSN. I know that Russia and US might have a formal "understanding" . Both seems to limit it at 12 to 14. US can choose to build more.

My doubt is whether China is limited by such agreements or understandings. How much SSBN China can build? What if China tries to match US ? Any backstage dealings regarding the current buildup? Has all this got anything to do with the trade relationship between the two countries?

Not really. Historically, China focused it's nuclear budget on making ways for the population and not just the missiles to survive in an exchange. The SSBNs are more for keeping the technologies alive than as a decisive arm of the nuclear force, unlike in UK and France where they are THE nuclear arm.

 

[gelgoog]

In France or the UK it is much harder to use land based systems to ensure second strike capability. Because the land area they have is so small it is much harder to hide them effectively. With regards to only having 4 SSBNs, I think the question is how many launch tubes and missiles you need to ensure enough deterrence. Those countries seem to assume 4 submarines is enough. China or Russia might need more because the amount of possible targets is larger.