Artillery and suppression.

[White Phosphorus]

Do all artillery pieces in the game cause the same amount of suppression, based entirely on firepower? Or are there some weapons (rockets) that cause extra morale failures like the machinegun.

[Sergei]

I'd ASSUME (without actual knowledge) that it is based just on the blast value. As rocket launcher ROF is higher than ordinary artillery, this should increase the amount of routing as they don't have time to recover from the shocks.

But what would I know of...

[Slater]

I woulda thought that rockets would have a higher suppresion than artillary with the same blast value because I've read first hand accounts of the sound scaring the sh*#t outta crack super troopers

[Monty]

Artillery have less suppression when there is snow.

The smaller the caliber, the larger is the dampening effect of the snow AFAIK.

Montya ak Mossie

[Quintus]

I'd be interested to find out for sure if arty type rather than blast value did have an effect on suppression. I remember that in the old war-games ruleset ('Firefly') I used to play that rocket bombardment gave a significant penalty to morale checks.

[JasonC]

I don't think the sound has any effect. The fact that all of the rounds come down in a minute or two certainly does, however.

The game figures the impact points, and then assigns a blast value to each unit for being close to an impact point, the blast value falling off with distance, apparently as a simple square root function. The range modified blast is then reduced for target cover, ignoring concealment. The result is final blast value for that round vs. that unit. It is then applied the same as infantry firepower. That is the mechanics of it.

When there are fewer rounds each with more blast, you get a "blast terrain" with sharper peaks, spaced farther apart. The mean distance to the nearest round is higher, with higher blast value compensating. The average suppression is similar, but "few big" puts an outlier portion of the targets close to bigger shells, and so typically inflicts more outright KIAs. If the blast values are small and the cover good (e.g. mortaring men in a trench), the final fp values will be so low only direct hits have any chance of getting even 1 guy.

Now, most of the rockets are large caliber - the Russian 82mms excepted. They come down all at once, instead of being spread over 3-5 minutes. As a result, the targets have less chance to rally between one nearby impact and another.

If only one round lands close over the whole firing pattern, that doesn't make any difference. But if 2-3 land close enough to cause significant suppression, then the rocket barrage is much more likely to cause panic, because the target unit won't rally back to "OK" before the next round lands nearby.

It is harder to rally the deeper you already are in suppression, too. So this effect would be pronounced with high caliber rockets, but not significant with little pop-gun ones ("alerted" can be recovered almost instantly).

You'd get the same sort of effect, though, firing 3 standard batteries at the same target for 1 minute, instead of 1 battery for 3 minutes. It isn't "rocket roar", it is a "shock" effect of additional nearby blast before there is time to recover from the last one.

In practice, I find that to get meaningful levels of suppression with the wide patterns rockets produce, you need decent caliber (132mm and up) and multiple modules (2-4) fired at about the same aim point, at the same time. Even then, the lasting destruction is modest, and most suppression effects have passed about 5 minutes after the barrage. The area hit is large, and a few units will get e.g. a nearby treeburst and take significant losses or break for good. But most will just go to pinned or cautious, down a man or two at worst. You really have to follow up within 2-3 minutes to benefit from the suppression.

For what it is worth.

[YankeeDog]

I obviously have no more knowledge of the actual game mechanics than the rest of you. However, here's what I've observed:

First of all, it's important to keep in mind that the "blast value" of a given shell is just an approximation of it's damage and casualty causing power. There are more details on this in the manual, but basically, CM actually tracks different attributes of an explosion, such as shrapnel cloud density & velocity, explosive energy etc. separately. IOW, it is quite possible to have two shells with the same 'blast' value, but somewhat different physical effects on the battlefield.

My playing experience seems to confirm this; I have observed a significant difference between different types of shells and how they affect morale and cause casualties, even when the blast value is similar.

At the very least, I agree with JasonC that rockets are more effective at routing infantry due to the advantages of having a large number of explosions impacting more or less simultaneously.

So rockets at least have the "Simultaneous Time on Target" advantage going for them. There does seem to be more to rockets' effects in CM than just this though. I'm strictly guessing here, but from the looks what I've seen in the game and what the manual says about blast value and what it represents, I think this has to do with the differences between different types of HE shells.

Many WWII-era rocket weapons had a much higher amount of HE relative to their size and weight than comparable artillery shells did. This meant more explosive energy from a rocket shell, but less shrapnel because there was a smaller amount of steel in the shell casing available to be turned into projectiles.

Among other things, more explosive energy = bigger concussion wave. While shrapnel is usually the most dangerous component of an explosion to nearby infantry, concussion waves also have very real physical and mental effects. A big enough one can literally pick you up off the ground and throw you around, causing serious injury without even breaking the skin. Smaller ones can still shatter eardrums, burst blood vessels in your nose and eyes, and otherwise mess you up. Even small explosions will leave you feeling like you've just woken up from a night of binge drinking with cheap vodka.

Having had the misfortune of being in the immediate proximity of a couple of small explosions, I can confirm that the concussion wave is very disorenting even when the injuries caused are otherwise negligible. Neither of the explosions caused me any actual physical harm, but both left me dizzy, disoriented, nauseous, and generally feeling like I had just been used as a punching bag by a prize fighter for several minutes. If a small explosion can do this, I can only imagine what a larger one would do.

When my infantry units get caught in a rocket barrage in CM, I will often see units under the barrage go panicked or worse even though they sustain few or no actual casualties. This seems to happen to a much greater extent with rocket barrages than it does with comparably sized (in terms of blast rating) gun artillery barrages, even when the units is on the edge of the barrage and has only a couple of explosions land close enough to it to be of any effect.

So my guess is that CM is in some way, shape or form CM is also modeling the large concussion wave aspect of rocket artillery, and it's corresponding effect on morale and 'combat fitness'. I couldn't say for sure, though. It just makes sense given what I've read about the weapons in real life and what I've seen in the game.

It would be a difficult, but not impossible, to test this for sure. You'd have to use a large number of arty with very low ammo loads (one volley each), and then issue "Target Wide" orders for all of them so as to cover an area about the size of a Rocket Barrage. You could then compare the results of Wounded/Killed, vs. Routed to a rocket barrage of similar blast rating.

I have not seen any evidence of a "sound morale effect" for rocket weapons, though. My guess is that this is not modeled - it would be a very difficult thing to quantify and assign a value to.

FWIW,

YD