SM-3 missiles

[Kobu]

Seriously, you keep arguing the same thing I've been saying for the last 4 posts.

Using SBX 1 bugs interceptions except those of the DF-21 at long range (why? I have no idea but that's how it is). Try shooting the DF-21 with the SBX-1 in play but when the DF-21 is less than 30NM away from the destroyer.

There is a bug with the SBX-1 that makes interceptions impossible. I don't know what else there is to discuss.
Can't you just say??: when the SBX-1 is on stage the SM-3s fail to intercept any ASBM. This way we can all wait for the developers to detect the problem and fix it instead of continuing to discuss nonsense.

[thewood1]

I think the issue is more than just the SBX. I think the SM-3 Blk IIA is the issue. Once its beyond the Aegis range, it has a success rate of less than 3% over many play throughs across multiple scenarios.

Once in range of the Aegis, it gets regular hits. So its not the SBX per se. Because Even with the SBX running, you get hits in range of the Aegis range of the DDGs.

I'll also point out that all the above see to work with the DF-21D. The DF-26 is IRBM and the Aegis struggles to engage.

So lets review your various hypothesis...

• "Against the DF-21D the SM-3 Block 2A has no problem and intercepts it, however the SM-3 Block 1B still has the same problem."

• "In this scenario, if you let everything happen normally, the SBX 1 platform helps track the DF-21D and there is no problem intercepting it, but in other scenarios where you only have the destroyer or for whatever reason you fire when the DF-21D is more close you will never be able to intercept it"

• "Without the SBX 1 platform I have no problem intercepting DF-21 and DF-26, with SBX 1 in play (this is where I got confused in the first tests) the SM-3E Block 2A is capable of intercepting at long range"

I have mostly been running my tests based on your initial post. Your comments is what has driven the confusion. I mean, I read those three comments and I am not sure what your ultimate approach is here. I've shown across multiple threads now...

Its the DF-26 as a target at extreme edge of SM-3 capabilities that is the issue. SM-3 I and II can hit the DF-21 frequently at short and long range...if the DDG has its radar on. The I and II can hit the DF-26 at shorter SAM range, if the trajectory of the DF-26 is long enough that its altitude has dropped when detected. The II has a slightly better than zero chance of hitting DF-26s at long range using and long-range radar, not just the SBX.

What I'm trying to do is clean this all up across two threads just so I can understand it. None of this matches any of the things I have found in the scenarios I build. Across two or three threads there have been contradictions, moving goal posts, and a lot of conjecture that doesn't match both contrived scenarios and more realistic scenarios.

[Kobu]

Once in range of the Aegis, it gets regular hits. So its not the SBX per se. Because Even with the SBX running, you get hits in range of the Aegis range of the DDGs.

Upload a scenario where with the SBX-1 a destroyer is capable of intercepting within AEGIS range. What I see is that whenever the SBX-1 is in play it is impossible to intercept an ASBM or even get to the roll of the dice, the SM-3 is simply dumb.

I have mostly been running my tests based on your initial post. Your comments is what has driven the confusion. I mean, I read those three comments and I am not sure what your ultimate approach is here. I've shown across multiple threads now...

At first I thought there was a problem with the SM-3 until I removed the SBX and saw that the SM-3 worked again. I've said it a couple of times that that was my mistake. My only mistake was thinking that the problem was somewhere else.

I'll explain it to you again: with only the DDG on scene I have no problem intercepting the two types of ASBM. Logically this occurs at short range since the DDG radar has a more limited range.

If I introduce the SBX against the DF-21 I am able to intercept it at a great distance (this is what led me wrong the first time) but within the distance of the DDG the SM-3 goes dumb (which makes no sense, that is capable of intercepting it at a long distance and not at a short distance)

With a DDG and the SBX against the DF-26, neither at long range nor at close range am I able to intercept it or reach the dice roll.

To clarify it even more, the missile is launched (in the launch window it appears green and allows you to place it) but the missile goes dumb and passes by the ASBM.

As I already said, there is something strange with the data link but the problem only occurs when the SBX is in play.

[DWReese]

With the SBX present, none of my SM-3s hit anything.

Without the SBX, the SM-3s seem to hit things that are within 200 miles, usually much less.

Without the SBX, or some other long range space radar, the SM-3 can't even see where to shoot. With the SBX (as I said), it can now see it, but it won't work because it is present. By that, they ALWAYS shoot, but they just can't hit anything.

Add the LORENZEN to the SBX naughty list. The same holds true with it, even at shorter ranges. If the LORENZEN is present, then no SM-3 works properly.

More testing is now needed for ALL VERSIONS of the SM-3 WITHOUT the SBX or LORENZEN present.

[thewood1]

You'll note I mentioned a few posts ago that it seems to be an issue with the combination of factors:

1) Long range radar with some kind of FC capability
2) IRBM (DF-26).
3) Long range SAM shots that depend on some kind of hand off from firing platform to long range radar

I am sure this is not a perfect representation, but I have had DF-26s taken out by IIAs. Just not very often. The pics above show this.

[thewood1]

I just tried turning off the DDG radar on the test scenario from Kobu. The DDG's SM-3 IIA kills the DF-21 every time. It looks like the FC gets conflicted between the SBX and the Aegis.

It killed the DF-21s almost every time with the DDG radar off. It came close tot eh DF-26s in three tries with no hits. Going to try adding an Aegis link to the SBX and see what happens.

[Zanthra]

One issue on top of the CEC issues between radars is that the intercept point is being calculated using the airspeed of the target as ground speed.

See this screenshot where the SM-3 is going directly towards an intercept point, calculated based on the target having a ground speed of 8033 knots (about 2.23 nm per second). The missile's ground speed is significantly less than that.

Even if everything worked properly (like adding the X-Band radar to the DDG instead of as a separate ship to avoid the CEC issues) the maneuvers the DF-26B makes to align with the target means the SM-3 has to make some ridiculous inertia defying maneuvers to catch the DF-26s.

An even bigger issue is that if these incorrect intercepts are being used to determine if the missile is in a valid DLZ for an interceptor, then it may be unable to fire when it should be able to, or be able to fire when it will never be able to get to the target.

[blu3s]

Another bug that I have noticed and that I believe has already been mentioned (at least in other situations) is that ECM countermeasures count twice when determining if they jam the missile.

Re this: If you have 2 DECM systems on your ship, the DECM endgame calculations will occur twice. Most US DDG's have two DECM systems. I have to check the arcs and how it is designed to work.

Also, I agree that sometimes DL connection is lost to early probably could be related to what Zanthra said about missile speed.

Regarding the rest of the thread, have you guys reach some clear conclussion?

I'm testing differences in missile performance using LRDR, SBX and both against DF-21,26 and 27. I'm using land based ABM defenses. SM-3, GBI and THAAD.

Missiles launched from different distances on every iteration.

The location of the BM targets/ABM installations and Radars is constant.


Let's see if I find noticeable differences in performance

[thewood1]

With the new patch, I am getting over 90% hits with SBX operating at very long distances. I hate to say this, but that might be just a little too good based on limited real-world testing.

[Nikel]

Hi

Reading the other topics and seeing that some achieve interceptions and others do not, I have managed to replicate both cases (when it does intercept and when it does not).

Scenario 1TEST shows when the SM-3 has no problem intercepting the DF-21D.







Scenario 2TEST shows when the SM-3 misses the target and passes by.







The difference between the two scenarios is the distance at which the SM-3 is fired, in the first it is fired shortly after the DF-21D is launched and in scenario 2 it is fired almost in the final phase.

Depending on the assets you have, you may be able to shoot sooner or later and that is where the problem is.

In this scenario, if you let everything happen normally, the SBX 1 platform helps track the DF-21D and there is no problem intercepting it, but in other scenarios where you only have the destroyer or for whatever reason you fire when the DF-21D is more close you will never be able to intercept it.

As I said before, for me the problem is in the data link, in scenario 1 it is cut off when the SM-3 is 8NM from the DF-21D and the SM-3 can already track the target by its own means, in scenario 2 On the contrary, the data link is cut when the SM-3 is 30NM from the DF-21D, making the SM-3 unable to find the DF-21D and passing by it.

Regards

Just run 2TEST 4 times with the new beta build 15, the SM-3 impacted the incoming missile the 4 times.

[Kobu]

Re this: If you have 2 DECM systems on your ship, the DECM endgame calculations will occur twice. Most US DDG's have two DECM systems. I have to check the arcs and how it is designed to work.

In this case there are two ECM systems but each one is for a part of the ship (they do not overlap). In my opinion, I do not believe that two systems of this type can be "added" against a threat.

Regarding the rest of the thread, have you guys reach some clear conclussion?

After doing a quick test this issue can be marked as fixed. If I find any other problem related to ballistic missiles I will open another post.


Having said this, the problem why I opened this thread and I think others also had it is that in scenarios where the SBX 1 asset was in play (normally you want to add this asset or other similar ones to benefit from some versions of the SM-3 and its long range) the SM-3 missiles went dumb and never hit, not even reaching the dice rolls.


Regards

[DWReese]

It wasn't just the SBX that had an issue. It was also the LORENSEN as well. That is another SBX-type of ship designed for ABM space search. So, whatever was the issue with the SBX was also the same with the LORENSEN. When that was removed, everything worked much better.

[DWReese]

I'm curious. Did version 15 fix the problem involving the SBX, or was that discovered too late for this release?

[caelunshun]

The issue wasn't really involving the SBX; it had to do with intercept calculations being incorrect, especially at longer ranges. Now, even with SBX, I am getting no more buggy behaviors with SM-3s.

[DWReese]

The issue wasn't really involving the SBX; it had to do with intercept calculations being incorrect, especially at longer ranges. Now, even with SBX, I am getting no more buggy behaviors with SM-3s.

If the issue had nothing to do with the SBX, then why did the performance improve with every scenario when that platform was removed? So, I don't find the first part of your statement to be valid at least as far as I can tell. There was definitely some component to the presence of the SBX and LORENZEN.

I do believe that calculations were and are an issue. With a single ship being the target, and with the DF-21s all coming from the same bearing, the ship can easily defend itself, with or without the SBX present. It works so well that this would make you believe that the issue has been completely resolved/

But, when multiple ships are firing at the the same group of DF-21s, and all are firing from a slightly different axis, as in thewood1's scenario, the program still has an issue. Even though the the missiles are fired with 75 miles of the target, the first batch of SM-3 seem to do much better than any following groups. Additionally, for some strange reason the SM-3s like to take a left turn when in doubt, and then fly away.

In my opinion, version 15 seems to be slightly better than 14, and with single ships being the victim and the defender, it calculations seem to work just fine. But, with multiple shooters, coming from different angles, it seem to produce very few kills. I'd say that it part of the way fixed.

[blu3s]

I did a test using LRDR and SBX.

THAAD interceptor works better with LRDR while SM-3 and GBI Missile works better with SBX.

https://imgur.com/a/etJDTeS

I can't see any issue with SBX at all.

We know that there is still room for improvement in this area and there are some specific issues with some ABM/BM engaments.


I wouldn't say that a 55% of hit (taking into account than at least 2 SM-3 misisles are expended against each BM) is a bad rate using multiples angles and multiples directions.

[thewood1]

Around 50% hit rate is probably the most realistic result you should get. Read some of the ABM failures. Comments about missiles heading off in different direction are in there.

[DWReese]

blu

"I can't see any issue with SBX at all."

I use one test scenario with one ship, and I fire 4 enemy DF-21s at it.

If the SBX is present, the DF-21s missiles are detected sooner (further away) than if I rely solely on the ship's radar.

If the SBX is present, the SM-3s are fired quicker, but NONE OF THEM ever engage, much less hit. They fly right on by. The SBX is located at the bottom right.

Missed with SBX JPG.JPG (64.02 KiB) Viewed 458 times

But, if I remove the SBX from the map, then the ship has to rely on its own radar. If that is the case, the ship detects and easily destroys all of the missiles.

This is a night and day difference.

The same is true for versions 14 and 15.

[thewood1]

Here we go again...

My ABM test scenario:

Note the SBX is on and detecting the DS-26s. About 80 SM-3 IIAs on the way and guiding.

Screenshot 2024-02-27 142254.jpg (969.63 KiB) Viewed 452 times

Note the SM-3 IIAs are impacting. About 70% hit rate by the end.

Screenshot 2024-02-27 142631.jpg (871.39 KiB) Viewed 452 times

[blu3s]

blu

"I can't see any issue with SBX at all."

I use one test scenario with one ship, and I fire 4 enemy DF-21s at it.

If the SBX is present, the DF-21s missiles are detected sooner (further away) than if I rely solely on the ship's radar.

If the SBX is present, the SM-3s are fired quicker, but NONE OF THEM ever engage, much less hit. They fly right on by. The SBX is located at the bottom right.

Missed with SBX JPG.JPG

But, if I remove the SBX from the map, then the ship has to rely on its own radar. If that is the case, the ship detects and easily destroys all of the missiles.

This is a night and day difference.

The same is true for versions 14 and 15.

It would be useful if you can share that scenario so I can have a look and measure the impact of the SBX in the scenario.