[WAD] B1776 - Bug Report: F-219 Sachsen (Type 124) Radar Failure Against Both Sea-Skimming and Hypersonic Targets

[Correcaminos]

Dear Developers,

I have completed a rigorous control test of the FFG F-219 Sachsen (Type F124) and its SMART-L / APAR radar systems.
The results indicate a critical and systemic failure in the modeling of its detection sensors at the extremes of its operational envelope, which completely compromises its Area Defense role.
The F-219's systems are failing in the detection and tracking of both high-altitude hypersonic targets and low-altitude subsonic targets:

1. Low-Altitude Target Detection Failure (Subsonic - Harpoon):The SMART-L search radar systematically fails to detect AGM/RGM-84 Harpoon anti-ship missiles (subsonic, sea-skimming) until a range of 18.7 nm and occasionally, as close as 2 nm.
This rendered the frigate unable to effectively use its SM-2MR or ESSM area missiles, resulting in 3 impacts from the Harpoon salvo.Conclusion: The radar model is critically blind to sea-skimming targets, nullifying its defense against subsonic missiles.

AGM-84 radar seeker actives


F219- cant detect anything

2. Hypersonic Target Tracking Failure (Kh-22M / AS-4):The F-219 was also incapable of detecting Kh-22M (AS-4 Kitchen) missiles at long range, failing to obtain the necessary precision track for the SM-2 launch.The error message recorded was: "No directors are able to illuminate this target (insufficient reflection, no LOS etc)".Critical Contrast: The F-101 (AEGIS) frigate did manage to obtain the track under these conditions (though limited by OODA Time), which suggests the APAR MFR model is overly restrictive or defective compared to the SPY-1D.In the second joint scenario, it was observed that the F-219 was completely incapable of executing any defensive action (due to the lack of illumination), leaving the entirety of the interception effort to fall upon the F-101 (AEGIS) frigate.



Final Conclusion:The evidence suggests that the F-219 Sachsen (SMART-L/APAR) radar model is compromised. I request a review of its detection profile against low-altitude targets and its tracking capability against high-speed/high-altitude targets, as it is currently less effective than the F-101 (AEGIS) and the F-215 (Brandenburg) in key scenarios.

Tested in B1774 and B1776.
Thank you very much,Correcaminos"

[Nikel]

What build of the game are you running?

She seems very capable in B1776.

[Correcaminos]

What build of the game are you running?

She seems very capable in B1776.

B1774 I´ll check B1776 Thnks

[Nikel]

This is what I see in several tests. Harpoons defeated.

H.gif (1.89 MiB) Viewed 597 times

[Correcaminos]

I tested it in B1776 and got the same results. The Sachsen is incapable of anticipating any type of missile; it can only use its point defenses. This is not normal.

Notice that it only uses its ESSM point defenses and is only capable of detecting the missiles at less than 20nm. Switch sides and you'll see the Harpoon seekers active from many more miles out.

If you try the other scenario with the AS-4s, you'll see how the F101 can defend itself and the F219 does nothing

[blu3s]

I can't check the scenario right now but just some indications.

Radar horizon is a thing, unless the radar is modeled (flagged) as OTH, it can't detect anything beyond radar horizon.

About the Khinzal detection, sounds like DB values, it's really difficult to get correct values and data for sensors. What I'd do is search more info about the specific radar capabilities, and based on that, you can write a ticket in the DB github explaining the difference in performance of the radar between real life open source docs and what is happening within Command.

But, as said, I couldn't check the scenarios so there might be an issue in command too, but how it looks, other sensors working and others no, it screams DB values

[Nikel]

But the Spanish Frigate has the advantage of the P-3B Orion. Is it not important?


Regarding the second test. I see that the Sachsen is passive, the ACs are attacking the Alvaro de Bazán. Nevertheless will destroy 1 or 2 of the ACs.

But if you remove the companion frigate, the Sachsen manages alone.

Is it that something is broken in the Sachsen, or that the Alvaro de Bazán is a better ships with better sensors?

[Correcaminos]

"The passivity of the Sachsen in defense at As-4 can be observed, despite being more modern/current than the F101."




It can be observed that the F-219 Sachsen is unable to detect the active seekers of the AGM-84 (Harpoon) with the ESM/EW systems.

@blu3s:

You are absolutely right, I believe the problem is directly within the Database (DB).

My impression is that the **long-range volume search radar (SMART-L)** is either **not operating correctly** or has detection values for low-RCS targets that are **much lower than they should be in reality**.

The detection below 20nm, forcing the ship to rely exclusively on the ESSM (point defense), is the symptom that the main sensor (either the SMART-L or the APAR for guidance) is **not acquiring the threat at the expected range**.

I will proceed to review the documentation and open a ticket on the DB GitHub as you suggest.


@Nikel:

I need to clarify a few things regarding the setup:

1. **P-3C/F101 Role:** In this test, the **P-3C Orion is only acting as a surface radar** to provide the F101 with initial targeting data for its missiles. The core of this test is simply to observe the **detection and targeting capability of the F219 Sachsen alone** when a missile is inbound.
2. **Sachsen's Passivity:** You are correct that the **Sachsen is currently completely passive** in its defense. This passivity is the main bug.
3. **The Solo Test Goal:** If we remove the F101 from the scenario, the F219 **still does not use its RIM-66 (SM-2) missiles**—it defaults exclusively to its **ESSM point defenses**. This behavior is highly abnormal and points to a fundamental failure in its AAW logic or sensor integration, which should be utilizing its RIM-66 for mid-range defense.
Thank you again for the feedback!

[thewood1]

On the harpoon one, I think Blue is right on this. The radar horizon is about 19nm at the radar's height. The Harpoons are detected at 18.7nm.

Screenshot 2025-12-11 182517.jpg (821.92 KiB) Viewed 531 times

[thewood1]

btw, ran it eight times and they were detected within 1nm of 18nm every time.

[Nikel]

The long range radar illuminator AN/SPG-62 present in the Alvaro de Bazan, missing in the Sachsen seems to make a difference. Added it to the Sachsen.

The Sachsen solo will fire the SM-2.

With the companion, in the manual fire it is green, however it is reluctant to use it and remains passive

[thewood1]

With a little more observation and removing the F-101 to isolate the issue, the SMART-L radar seems to be doing what its built to do...detects aircraft and missiles at range. In the AS-4 scenario, its detecting the Backfires at almost 250nm and AS-4s at 115nm. But its not shooting because the APAR FCR is not illuminating missiles until about 40nm (with a theoretical range of 90nm). But its firing the SM-2s at the backfires at almost 80nm after IDing them as hostile.

With the F-101 in the scenario, the Aegis completely out ranges the APAR as an FCR. Thats 175nm vs 90nm SPG-62 vs APAR. And the Aegis doesn't start firing at the AS-4s until about 90nm. Thats about 50% of the theoretical range of the SPG-62. Apply that same 50% against the AS-4s for the APAR and you get 45nm. So 40nm is not unreasonable.

In short, I think its working OK. The critical factor is comparing the ranges of the FCRs. Thats my guess at it.

Edit...Sorry...the FCR on F-101 is the SPG-62 for SM-2s, not the SPY-1.

[thewood1]

Also note that the AS-4 is not a truly hypersonic missile.

[Dimitris]

Marking this as WAD, with the caveat that a review of the APAR stats may be in order, if a DB-tracker ticket with suitable sources can be submitted.

The SMART-L seems to work exactly as expected, both in its horizon limit (it is a relatively low-sited sensor after all) and its capability to detect threats at high altitude and long range.

[Nikel]

I know this is for the github site.


Same sensors in the Dutch frigate Iver Huitfeldt. Seaforth Naval Review 2014. Previewed in Google Books.

1.png (149.17 KiB) Viewed 429 times

2.png (871.54 KiB) Viewed 429 times

[Correcaminos]

I know this is for the github site.


Same sensors in the Dutch frigate Iver Huitfeldt. Seaforth Naval Review 2014. Previewed in Google Books.



1.png2.png

Thanks for the great feedback and the source images, @Nikel! We nailed the issue down:

The **SMART-L is fine** (detects missiles at 115+ nm—WAD).
The actual problem is the **APAR Fire Control Radar (FCR)**. It's too passive and won't achieve lock for the SM-2 until ~40 nm.

The **F219 Sachsen** is a superior **Area Defense (AAW)** ship with an **AESA radar** (APAR). Limiting its engagement range to 40 nm against a big missile like the AS-4 essentially breaks its primary role. The FCR should be locking on closer to **60-70 nm** to utilize the SM-2 properly.

I'm using the **Seaforth Naval Review** source (thanks, @Nikel!) to argue that the APAR's **81 nm tracking capability** means the current 40 nm value is too low.

I'm taking this data and the source documentation straight to the **DB GitHub** to ask for a correction on the APAR FCR values.

https://github.com/PygmalionOfCyprus/cm ... ssues/6786



Thanks again for the collaborative testing!