054/A FFG Thread II

Tam

Brigadier
Registered Member
Mission kill is enough for this mission profile(i.e. for medium/small surface combatants), in my humble opinion.
If the ship needs to be finished off (or reliably brought down) - this is another mission, which complicates both ship and missile design substantially.
Especially - for China, which is expected to fight within reach of the mainland. If necessary - crippled unit can be finished off by literally anything, from surface gunfire to a drone with an LGB.

I think it takes many "turns" in operations to kill a frigate if you don't take it out in one blow. Being able to kill the frigate does not equate to killing that frigate efficiently, you want it killed as efficiently as possible. Do note that China, or at least internal observers, believe that the YJ-18 is the best antiship missile in the planet, and appropriates that accordingly.
 

Tam

Brigadier
Registered Member
Simple. MPQ-53 is a pulse doppler phased array. Because it uses TVM, there is no dedicated illumination. The same PD beam the radar uses to track the target generates RF reflections that are picked up by the monopulse receiver in the missile and downlinked to the ground control system.

TVM is SARH one step backward, essentially SARH with the station in the loop for a terminal stage.
 

Tam

Brigadier
Registered Member
Any missile(or plane) can go 0.5m above the airfield. The problem is doing the same above actual sea.
Supersonics - especially air-breathing ones - will never catch up to subsonics in this aspect - and the faster they go, the more the difference. It's pretty much a hard limit.

Almost all modern subsonics take measures to hide their plume; NSM - relatively less, LRASM - relatively more. Supersonics are in no competition here, because of hot air(ramjets especially so), and comparatively huge&uninterrupted flow of air. Speed doesn't come by itself.
p.s. on turbojets - it depends on the missile in question. There are small/low resource turbofans. Furthermore, small turbojets are exactly that - small.

Yes.
(1)rule of thumb: all supersonic ASCMs use ARH. Quite a few subsonics are either mixed or fully passive - it depends on the concept of the missile in question.
(2)all missiles need to find target for their attack. Supersonics tend to do it earlier - because, obviously, (1)their speed and thus search has to be performed correspondingly earlier, and (2)they typically have no time to perform overly complex search patterns.

Use of datalinks (external updates) actually plays against supersonics. Because if you have access to them - one of the big advantages(ability to shoot on unapdated target data due to far higher speed of the missile) actually goes down the drain. If you're investing in sufficient airspace control to provide these updates - you may very well both save money and make your attack sneakier by avoiding the sound barrier.

Your whole shock cone reflects, and you have a comparatively huge missile, which flies comparatively higher, and can't (aerodynamics!) hide its intakes the way subsonics can.
p.s. Kh-59 on your photo isn't even a true ASCM, more of a 1980s vintage multi-purpose stand-off precision weapon. Her modern relative looks like this:
message-editor%2F1527284929206-kh-59mk2_missile_at_maks-2015_01.jpg

This is an interesting part. For anything better than an educated guess, we'll have to go into chinese naval periodicals - and being blunt, I neither can read technical mandarin fast enough to do it now, nor do I have access to the translations (not a staff naval officer).
But given the choice of platforms - IMHO it points exactly to that.
YJ-12 is being employed from:
-H-6 family(main platform).
-Land launchers(defensive platform)
-Older destroyers(persistent at-sea platform).
While ideas of their employment may be different (and these forces are inherently flexible in their employment) - this is quite a typical "defensive" sea denial setup(defense through the threat of overwhelming salvo). In principle this mix, relying on mainland- and space-based targeting assets can reliably destroy just about any viable surface force within its reach, freeing modern force for other duties.
With this force at its current/future size(including units coming out from MLU) - I don't think there is need to arm frigates and corvettes with more heavy supersonic missiles. Their instrument is of far more tactical OtH nature, and their targets are far more diverse.


Supersonics have already caught up in that aspect in terms of sea skimming height if they attain 5m to 10m range. There is no hard limit. Its a matter of how fast the electronics can respond. YJ-18 or Kalibr sprinter is said to go down as low as 3 meters. 5 meters is still pretty high if that is what you expect for a wave. You would have to be in stormy or heavily windy conditions for it to be a problem.

You are completely wrong about subsonics being purely passive. No missile other than an ARM, can use passive in the terminal stage, because the target is moving even for a ship, and passive just isn't precise and reliable enough for that. It will only tell you that this is the general area of the target, not X marks the spot, and the final leg of the journey needs to be active to attain the precision you need. That's why ARMs are used in static fixed sites, and even then have to be supersonic so the ARM can be hitting the target before it gets away. Have you ever seen a subsonic ARM missile? You can go passive only in the midphase, avoiding datalink use (read below why you want to use it as least as possible), but terminal is always either active radar or IIR. I should add that there is no reason why a supersonic cannot use passive during its midphase or cruise phase either, and for that remember that ARMs are supersonics. Perhaps you have forgotten about the Kh-31P?

One negative about passive is that it takes quite a bit of space, competing for space in a missile with other things like propellant or warhead. You are going to need circuitry and computing power to analyze, breakdown, all the signals, and make sure you are targeting a warship instead of the navigation radar of an innocent freighter. If a ship has LPI (Low Probability Intercept) radars, such as using AESAs and solid state navigation and search radars, chances are you won't be able to identify its signal and it will look like background noise. Or the ship will just go EMCON and there you go.

Datalinks are an even bigger advantage for supersonics. A supersonic requires lesser datalink updates for moving target correction, since more or less due to its speed, the target is still likely near where its original targeted coordinates. For a subsonic, the lag of time is a few times over, perhaps 3 times as long, and the target would have move much further away from its original coordinates. That requires further updates. Against closer targets, the supersonic missile can go full autopilot.

Every additional time you use the datalink, opens a chance and a risk that it will be detected by the opponent's ESM. With the messier communication traffic, the less stealthy you are. So the less updates, the better.

The straight wings of the Kh-59MK2---looking rocket powered by the way---are not stealthy by a long shot, and straight sides aren't either. There are easy 90 degree corners for radio reflection there. Plus you cannot hide plumes completely, the thermal plume will extend way way longer than the length of the missile over many times. The best way is to cool the exhaust and you need a high bypass turbofan for that.

If they are not arming Type 054As with YJ-12s then its because this is not what they view of it for its mission purpose. That can change in the future, and the Type 054A is overengineered to exercise that option. If you are building something with an expected life of 30, more likely 40 years, the ship is going to be built with margins and slack for whatever options that may arise in the future.
 
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nlalyst

Junior Member
Registered Member
All the transmitters in the STIR are multiplexed by mode. They cannot be operated in parallel because you have a single monopulse feed and the transmitters take turns, according to the mode selected, in using it. Thus if the CW is using it to illuminate the target, the CW has access to the monopulse feed and the pulse radar cannot operate. Single tasking mode switching. When operating the CWI, the STIR has to track the target on its own via CWI. The only time you can have pulse radar operate in parallel with CW with a monopulse antenna is to have them on two separate antennas.
I don't know about that. None of my sources went into that detail. Maybe, maybe not.

SPG-51 is an example of a pulse doppler radar tracker sharing the same antenna as the CWI illuminator. Friedman says that there are separate feeds for the two. The separate feeds are apparent in the photos:
SPG-51C_Radar_on_board_JS_Hatakaze%28DDG-171%29_at_Port_of_Sakaisenboku_20141019-03.JPG


SPG-60 started as a monopulse doppler radar. CWI (CW injected) was added under FY90 program to provide a second Sea Sparrow control channel for Spruance class destroyers.

The PDF you posted showed the STIR inside the egg shaped radome of the Mk 92 and at the end of the document, mentions the Dutch relationship. You have to argue if those other sources are wrong which I doubt they are not.
The Mk 92 is a license copy of the Dutch WS-20 FCS. That doesn't mean that the building blocks cannot be of American origin. There is no contradiction between the sources.
 
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nlalyst

Junior Member
Registered Member
TVM is SARH one step backward, essentially SARH with the station in the loop for a terminal stage.
TVM is a form of command guidance all the way to target. It is not "essentially SARH" because the missiles do not carry the computers required to fully process the received radar signals and continually compute an interception path. It is more accurate to describe it as having some features of SARH, while being essentially command guidance.

In TVM, the ground radar must track the missile. This is not necessary in SARH.
 

Gloire_bb

Captain
Registered Member
Supersonics have already caught up in that aspect in terms of sea skimming height if they attain 5m to 10m range. There is no hard limit. Its a matter of how fast the electronics can respond. YJ-18 or Kalibr sprinter is said to go down as low as 3 meters. 5 meters is still pretty high if that is what you expect for a wave. You would have to be in stormy or heavily windy conditions for it to be a problem.
It becomes a religious argument that won't lead to anywhere. Let's agree to disagree.
You are completely wrong about subsonics being purely passive. No missile other than an ARM, can use passive in the terminal stage, because the target is moving even for a ship, and passive just isn't precise and reliable enough for that.
protivokorabelnaya_raketa_kongsberg_nsm-z3rc2wvn-1524400345.jpg
Have you ever seen a subsonic ARM missile?
taiwan-drone-swarm-tadte-2019-e1566585123736.jpg

Datalinks are an even bigger advantage for supersonics. A supersonic requires lesser datalink updates for moving target correction, since more or less due to its speed, the target is still likely near where its original targeted coordinates. For a subsonic, the lag of time is a few times over, perhaps 3 times as long, and the target would have move much further away from its original coordinates. That requires further updates. Against closer targets, the supersonic missile can go full autopilot.
Your argument is self-defeating.
As per your own argument, lesser need to rely on datalinks is the advantage of supersonics. And, vise versa, if updates are not a problem(your navy maintains a necessary degree of sea/airspace control) - it goes away. Simple as that.
And this is precisely why supersonics appear so much on applications where updates aren't assured. This was one of the reasons for their birth, to begin with.
The straight wings of the Kh-59MK2---looking rocket powered by the way---are not stealthy by a long shot, and straight sides aren't either. There are easy 90 degree corners for radio reflection there. Plus you cannot hide plumes completely, the thermal plume will extend way way longer than the length of the missile over many times. The best way is to cool the exhaust and you need a high bypass turbofan for that.
Missile shows its front to the enemy, not sides, and wings have some wing sweep angle. Point taken, though - there are indeed better missiles from the all-aspect RCS PoW.
Plume from a small transonic missile may easily be hidden. Strictly speaking - it's one of big advantages of supercruise even for 5th gen fighters - heat signature goes down dramatically. And here we're talking about very small engine right next to the water.

If they are not arming Type 054As with YJ-12s then its because this is not what they view of it for its mission purpose. That can change in the future, and the Type 054A is overengineered to exercise that option.
1st is true. 2nd - we don't know.
I'd personally suggest they can't just switch from YJ-83 to YJ-12 overnight.
 

Gloire_bb

Captain
Registered Member
Being able to kill the frigate does not equate to killing that frigate efficiently, you want it killed as efficiently as possible.
Full salvo of P-700 then!
Mach 2.5, 750kg warhead, up to 24 in a single salvo - frigate will be dead for sure.
Do note that China, or at least internal observers, believe that the YJ-18 is the best antiship missile in the planet, and appropriates that accordingly.
Best anti-ship missile on the planet by which parameter? Indian internal observers, for example, believe that Brahmos is the best anti-ship missile on the planet. Russian will say it's actually Zirkon. Americans will say it's LRASM. And it may very well be that all 4 will be right at the same time.

Even China itself simultaneously produces half a dozen ASCMs simultaneously, not counting ballistic missiles. Why when there is the best one out there?
p.s. and for 90% of flight it's subsonic.;)
 

do3jack

New Member
Registered Member
Full salvo of P-700 then!
Mach 2.5, 750kg warhead, up to 24 in a single salvo - frigate will be dead for sure.

Best anti-ship missile on the planet by which parameter? Indian internal observers, for example, believe that Brahmos is the best anti-ship missile on the planet. Russian will say it's actually Zirkon. Americans will say it's LRASM. And it may very well be that all 4 will be right at the same time.

Even China itself simultaneously produces half a dozen ASCMs simultaneously, not counting ballistic missiles. Why when there is the best one out there?
p.s. and for 90% of flight it's subsonic.;)
Zirkon > YJ-18 > YJ-12 ≈ Brahmos > LRASM
 

Gloire_bb

Captain
Registered Member
Zirkon > YJ-18 > YJ-12 ≈ Brahmos > LRASM
1. Hypersonic ASCM - completely lacks low altitude profile - not yet in service - only fits in a few strike VLS-equipped ships and SSGN;
2. Large subsonic ASCM with a separate supersonic terminal stage - fits in dozens of strike VLS equipped ships and TT;
3. Supersonic ASCM(somewhat lighter) - a few large ships, dedicated heavy bombers (up to 4), and ground launchers;
4. Supersonic ASCM(somewhat heavier) - all large ships, purpose build heavy fighters (1 per plane), and ground launchers;
5. Subsonic stealthy ASCM with a heavy warhead - tactical fighters (up to 4-5) and bombers (up to 24).

This is a surface-level, without diving deeper into their warheads, seekers, algorithms.
The point is: they are completely different. And arguably the last one on your list, the least impressive one - is actually the most important one.
 

Tam

Brigadier
Registered Member
I don't know about that. None of my sources went into that detail. Maybe, maybe not.

SPG-51 is an example of a pulse doppler radar tracker sharing the same antenna as the CWI illuminator. Friedman says that there are separate feeds for the two. The separate feeds are apparent in the photos:
SPG-51C_Radar_on_board_JS_Hatakaze%28DDG-171%29_at_Port_of_Sakaisenboku_20141019-03.JPG


SPG-60 started as a monopulse doppler radar. CWI (CW injected) was added under FY90 program to provide a second Sea Sparrow control channel for Spruance class destroyers.


The Mk 92 is a license copy of the Dutch WS-20 FCS. That doesn't mean that the building blocks cannot be of American origin. There is no contradiction between the sources.


What I see here is that the monopulse feed is the one that is reflecting on the parabolic, but the feed in the center isn't a monopulse feed. A monopulse feed requires four horns, which are four separate emitters.

download.png


You only have a single emitter there for the CWI. The missile receiver will have to work like this. You are measuring off from the differences of the same signal as it is received from four receivers set in four different places.

103-e7d17a017ad809a86d081946ca6d4618.jpg


I would agree on the Mk. 92. However, STIR having both X and K band PD transmitters does not make sense. In fact its insane. X and K band are used for the same purposes, which is gunnery. This is unreasonable duplication. Furthermore, PD circuits are bulky, or at least they used to be at one time. They are power hungry with those transmitters. If we have a theoretical example of a radar with an X band pulse transmitter of 2kw and a K band pulse transmitter of 2kw, why not have a single transmitter, a single band with 4kw? That would have been better. The X and K-band PD transmitters on the STIR are choices for the customer, choosing either one or the other, and there are variants in the sales catalog for them to pick which.
 
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