[ΤWEAK/FIXED] AAW hit rate of naval guns against drones

[erick33]

I have a question regarding the anti-aircraft (AA) hit rates of naval guns, specifically concerning their effectiveness against drones. I am unsure whether this falls under a Tech Support issue or a Database (DB) issue, but I am reporting it here first.

Based on indirect reports from various recent naval engagements in the Middle East, there is information indicating that naval guns like the Mk.45 5-inch gun and CIWS like the Phalanx are highly effective at intercepting slow, large suicide drones such as the Shahed-136.

Real-World Case Studies
USS Carney (2023–2024): While operating in the Red Sea, the USS Carney conducted 51 anti-aircraft engagements. By utilizing the Mk.45 gun and CIWS during these operations, they were able to conserve their missiles and engage targets efficiently.

Hellenic Navy Frigate Psara: While operating off the coast of Somalia, this frigate successfully utilized its Mk.45 gun to intercept drones, further proving the effectiveness of naval artillery in anti-drone warfare.

Reference:
https://www.twz.com/sea/uss-carneys-red ... capability
https://www.twz.com/sea/greek-warship-g ... -new-video
https://nationalinterest.org/blog/buzz/ ... ne-defense

Technical & Historical Context
Practically speaking, this is not surprising. Large suicide drones like the Shahed-136 have a substantial radar cross-section, making them easy to detect. Furthermore, their slow flight speed allows for straightforward tracking using systems like the Mk.20 EOSS. Consequently, it is quite expected that an electronically controlled Mk.45 gun firing proximity-fuzed shells can successfully shoot down these drones.

Historically, during World War II, 5-inch anti-aircraft guns managed to shoot down Japanese Kamikaze aircraft—which were much faster than modern low-end drones—using what we would now consider very low-performance fire control systems. Considering this precedent, it is highly predictable that modern naval guns would boast a high probability of kill against contemporary drones.

Issues in the Current CMO Database
The problem is that the hit rates for these naval guns are currently set far too low in the CMO database:

Mk.45 5-inch gun: ~5% AA hit rate

76mm OTO Melara: ~2% AA hit rate

Mk.8 4.5-inch gun: ~4% AA hit rate

While these hit probabilities are perfectly reasonable when targeting modern jet fighters, applying these exact same figures to slow-moving drones results in a practical hit rate of a mere 1%. Similarly, the Phalanx CIWS has an approximately 30% hit rate against much faster cruise missiles, yet this exact same rate is being uniformly applied to drones.

Anti-Aircraft Range Issue:
In addition, the anti-aircraft range of naval guns in the game is set quite short, at around 1.5 nm. According to known real-world data, the effective AA range of the Mk.45 gun is approximately 7,000 meters, or roughly 4 nm.

Reference: http://www.navweaps.com/Weapons/WNUS_5-54_mk45.php

Conclusion
In conclusion, the existing anti-aircraft hit rates and ranges—which were clearly designed with fast jet fighters or cruise missiles in mind—are being uniformly applied to drones, leading to highly unrealistic outcomes in simulations. I believe this specific area requires a DB adjustment or modification.

I look forward to your positive response regarding this issue!

[thewood1]

"In addition, the anti-aircraft range of naval guns in the game is set quite short, at around 1.5 nm. According to known real-world data, the effective AA range of the Mk.45 gun is approximately 7,000 meters, or roughly 4 nm."

Is that the horizontal range?

[Dimitris]

Interesting point and research, thank you.

I think this can be very broadly broken down into two "subcategories":

1) Hitting the target. Our nominal PH values assume a cooperative (non-evading) target that is large in size (B-52/B747) and high-subsonic in speed. We do include modifiers for smaller physical size and higher speed, but not for smaller speed. A significantly slower target is indeed easier to hit than nominal.

There is also the matter of airburst AAW rounds (either pre-set timer [AHEAD etc.] or proximity-fused). These are substantially more efficient against fragile air targets. The examples you have shown above are, I think, with shells with contact-optimized fuses. The USN five-inch guns in PTO became really effective in AAW only once CVT rounds were widely adopted. We introduced the relevant mechanics for this a couple years ago IIRC, so it would be interesting to see the same figures vs drones when using such ammo.

2) Actually destroying the target, once it has been hit. On this aspect we are currently facing probably the reverse issue: Because aerospace weapons do not have a gradual damage model like aircraft and other platforms, they are insta-killed once hit by any relevant weapon (see this thread for an example).
We very recently introduced weapon durability/fragility for a similar issue on laser engagements (lasers were insta-killing everything within their theoretical envelope, which is not nearly how things work in RL), and it is very likely that this system will also be re-used for non-laser AAW weapons in the future.

Thanks again.

[erick33]

"In addition, the anti-aircraft range of naval guns in the game is set quite short, at around 1.5 nm. According to known real-world data, the effective AA range of the Mk.45 gun is approximately 7,000 meters, or roughly 4 nm."

Is that the horizontal range?

I suppose that’s probably right

[erick33]

Interesting point and research, thank you.

I think this can be very broadly broken down into two "subcategories":

1) Hitting the target. Our nominal PH values assume a cooperative (non-evading) target that is large in size (B-52/B747) and high-subsonic in speed. We do include modifiers for smaller physical size and higher speed, but not for smaller speed. A significantly slower target is indeed easier to hit than nominal.

There is also the matter of airburst AAW rounds (either pre-set timer [AHEAD etc.] or proximity-fused). These are substantially more efficient against fragile air targets. The examples, you have shown above are, I think, with shells with contact-optimized fuses. The USN five-inch guns in PTO became really effective in AAW only once CVT rounds were widely adopted. We introduced the relevant mechanics for this a couple years ago IIRC, so it would be interesting to see the same figures vs drones when using such ammo.

2) Actually destroying the target, once it has been hit. On this aspect we are currently facing probably the reverse issue: Because aerospace weapons do not have a gradual damage model like aircraft and other platforms, they are insta-killed once hit by any relevant weapon (see this thread for an example).
We very recently introduced weapon durability/fragility for a similar issue on laser engagements (lasers were insta-killing everything within their theoretical envelope, which is not nearly how things work in RL), and it is very likely that this system will also be re-used for non-laser AAW weapons in the future.

Thanks again.

Thank you for your response! Regarding the first point, as shown in the last photo, the test used the Mk187 HE-MFF (Mk.419 Fuse), which is a multifunction proximity-fused round. Despite this, it can still be observed that it has a relatively low hit rate. Thank you for addressing this point!

[Nikel]

Another example with video.

https://www.sofx.com/french-navy-frigat ... hatgpt.com



In CMO, only the OTO Melara Super Rapido gun is available for the French frigate, reportedly the one used in the video.

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[Dimitris]

We added some improvements & fixes for the next update:
* Fixed: Combined fuzes (like the Mk149 on the Mk187 HE-MFF) were not airbursting correctly against relevant targets.
* Tweak: When the target speed is well below the weapon nominal max target speed, the PH rises considerably (+10% if it's under half of nominal, +20% if it's under 1/4th of nominal)

We are also looking at post-impact kill assessment for weapon targets, re-using the weapon "fragility" framework we recently introduced for lasers.

For changes to the data itself (ie. gun AAW range & nominal PH) please open a ticket on the DB Github tracker: https://github.com/PygmalionOfCyprus/cm ... sts/issues

[erick33]

We added some improvements & fixes for the next update:
* Fixed: Combined fuzes (like the Mk149 on the Mk187 HE-MFF) were not airbursting correctly against relevant targets.
* Tweak: When the target speed is well below the weapon nominal max target speed, the PH rises considerably (+10% if it's under half of nominal, +20% if it's under 1/4th of nominal)

We are also looking at post-impact kill assessment for weapon targets, re-using the weapon "fragility" framework we recently introduced for lasers.

For changes to the data itself (ie. gun AAW range & nominal PH) please open a ticket on the DB Github tracker: https://github.com/PygmalionOfCyprus/cm ... sts/issues

Was this update applied to build 1892? After testing it out, it doesn't seem like there are any significant changes.

[Nikel]

The change related with the target speed is visible in the calculations, however the nominal PH is so low that the effect is not noticeable.

[Dimitris]

If we're talking specifically about the Mk187 HE-MFF, there is an additional factor which is currently a DB error: The gun round does not have the "Capable vs seaskimmer" flag, which it should (the fuze is specifically designed with VLow targets in mind). Because of this, it suffers a severe penalty as long as the Shahed remains at VLow altitude.

I have asked the DB team to add this flag to this gun round (and a few others that have a similar design) for the next DB update.

[Dimitris]

Was this update applied to build 1892? After testing it out, it doesn't seem like there are any significant changes.

Note these lines:

Target speed modifier: 20%

Proximity fuze (Gun 81-150mm) - PH increased by 4x"

(Perhaps I should make it "+20%" to make the benefit more explicit...)