055 Large Destroyer Thread II

[kwaigonegin]

The higher up the radar is, the further out it can see because less is blocked by the curvature of the earth. This is especially important for detecting small surface vessels and sea skimming missiles.

That to me is the biggest 'design flaw' of the current generation of PLAN 'Aegis' large surface combatants.
They should've been mounted much higher.
As a comparison look at how high the arrays are on the Fridtjof class frigates.
I like to think the next gen of PLAN warship that utilizes fixed arrays will have them mounted over the bridge like on the illustrations.

 

[Gloire_bb]

That to me is the biggest 'design flaw' of the current generation of PLAN 'Aegis' large surface combatants.
They should've been mounted much higher.
As a comparison look at how high the arrays are on the Fridtjof class frigates.
I like to think the next gen of PLAN warship that utilizes fixed arrays will have them mounted over the bridge like on the illustrations.

it's a tradeoff, placing the bridge lower(and placing heavy sensor towers too high up - with obvious stability limitations on what you can bring up - and how high up) isn't exactly good either.

The key is ultimately to place datalinks and 3d air radar as high up as possible. Placing of everything else is more of a preference.

 

[ismellcopium]

That to me is the biggest 'design flaw' of the current generation of PLAN 'Aegis' large surface combatants.
They should've been mounted much higher.
As a comparison look at how high the arrays are on the Fridtjof class frigates.
I like to think the next gen of PLAN warship that utilizes fixed arrays will have them mounted over the bridge like on the illustrations.

...doesn't the 055 have smaller omnidirectional AESAs on the integrated mast for sea skimmers? Similar to the role the top rotating AESA on the 054B/new 052Ds plays. My understanding is the main large arrays aren't for low altitude/sea skimming target detection.

 

[taxiya]

That to me is the biggest 'design flaw' of the current generation of PLAN 'Aegis' large surface combatants.
They should've been mounted much higher.
As a comparison look at how high the arrays are on the Fridtjof class frigates.
I like to think the next gen of PLAN warship that utilizes fixed arrays will have them mounted over the bridge like on the illustrations.

The radar on Fridtjof is SPY-1F FARS (frigate array radar system), it is much smaller (2.4m vs. 4m) and ligher, and above all only half (54%) of the range of SPY-1D. That is why it can be mounted so high without sinking the ship. With only 54% of range, high-mounting doesn't have advantage since the beam simply can not reach very far any way.

 

[kwaigonegin]

The radar on Fridtjof is SPY-1F FARS (frigate array radar system), it is much smaller (2.4m vs. 4m) and ligher, and above all only half (54%) of the range of SPY-1D. That is why it can be mounted so high without sinking the ship. With only 54% of range, high-mounting doesn't have advantage since the beam simply can not reach very far any way.

Yes of course it's smaller but so is the hull.
A large displacement ship like the 055 or even the 052Ds can easily mount the arrays much higher than the current design and that's why I postulated PLAN's future ships may very likely have above brudhe arrays like in the illustration.

Same with USN. The only reason why the AB flt IIIs are still around is due to budgetary reasons and also because the original AB hull design is pretty much bulletproof.

 

[Gloire_bb]

Yes of course it's smaller but so is the hull.
A large displacement ship like the 055 or even the 052Ds can easily mount the arrays much higher than the current design and that's why I postulated PLAN's future ships may very likely have above brudhe arrays like in the illustration.

Same with USN. The only reason why the AB flt IIIs are still around is due to budgetary reasons and also because the original AB hull design is pretty much bulletproof.

To fit full-sized 4-side AESA arrays without stability issues, we're looking towards Kirov size.

This will require entirely different machinery, probably will add passive protection... and here we are, "Kirov reporting" indeed. 055 is fully capable, yet it is something that can be produced at scale. Are several meters of fire control position(because supplementary x-band air search radar is still in the highest position on the ship anyway - believed to be in cone right under the spire) really that important?

 

[Blitzo]

Yes of course it's smaller but so is the hull.

The hull of the Nansen class is shorter than 052D, however it has a similar beam (16.8m vs ~17m).
If you are talking about topside stability (which is related to the ability to mount heavy objects like radar arrays higher), beam is particularly important.

A large displacement ship like the 055 or even the 052Ds can easily mount the arrays much higher than the current design and that's why I postulated PLAN's future ships may very likely have above brudhe arrays like in the illustration.

Same with USN. The only reason why the AB flt IIIs are still around is due to budgetary reasons and also because the original AB hull design is pretty much bulletproof.

The 055 has a beam of some 21m (about the same as a Burke), 052D has a beam of 17m (narrower than Burke).

I don't see why you think they are able to "easily" mount their full sized AESAs higher than they already are, especially if you're comparing it to the Burke class which are mounted in a similar position and when 055 is barely much wider than a Burke and in the case of 052D is significantly narrower.



If you want to mount the same sized AESAs higher than they already are on those two respective classes, while not compromising on other subsystems and armament, then what you need is a bigger -- specifically, wider hull. And a wider hull is basically a new ship class.



In fact, for 052D and 055 I suspect that they have probably already placed their AESAs as high as they are able to do so on the existing hullforms that they have, and if they wanted to place the same sized AESAs higher than they are, then they would have to either have a much bigger and wider new hull, or if they want to adapt the existing hull they'd need to significantly compromise on other aspects of the ship like other subsystems, weapons, etc.

 

[HardBall]

it's a tradeoff, placing the bridge lower(and placing heavy sensor towers too high up - with obvious stability limitations on what you can bring up - and how high up) isn't exactly good either.

The key is ultimately to place datalinks and 3d air radar as high up as possible. Placing of everything else is more of a preference.

Also the internal structural support and cooling ducts get much more complicated, if these large AESA arrays are mounted high on a mast. Actually the more complex cooling setup alone, when these large sensors are high up in the superstructure, sometimes limits the size and power draw of the arrays.

 

[HardBall]

...doesn't the 055 have smaller omnidirectional AESAs on the integrated mast for sea skimmers? Similar to the role the top rotating AESA on the 054B/new 052Ds plays. My understanding is the main large arrays aren't for low altitude/sea skimming target detection.

It also has to do with what they can detect, not just LoS of the mount.

Most of the recently designed subsonic cruise missiles are focusing more on low observability. In order to detect those reliably, and track long enough to have a firing solution, you would need a certain aperture radar along with much more compute throughput to run through digital signal filters. Especially if you are talking about tracking them at the limit of LoS when the sensors is mounted high up that could have views much further than that mounted below the bridge.

For some of you who work in this area, you may be very familiar with the likes of unscented Kalman filter, which is one of the earlier generation signal processing models. Today some of the platforms have much more sophisticated models to specifically dull the edge of low observability, but as usual, computational capacity comes into play, which ultimately means space, power draw, and potentially very significant cost increase, if you want to outfit multiple separate systems to have that level of tracking capability, you would need to pay significant cost from other areas of the design of the platform.

 

[by78]

One more magazine scan that shows off the size of the 055 compared to the replenishment ship.