Space combat damage

[Starstrider42]

I'm confused by how weapon damage in the ship designer translates to damage in actual combat. I'm currently deploying ships armed with Copperhead missiles, which are rated for 30.7 damage with an explosive warhead (80% vs. armor). I assumed this meant that a missile could reliably penetrate up to 24 points of armor.

However, in combat (version 0.3.99) the missiles do only 3.9-5.8 damage each, making them easy for armor to shrug off. Even stranger, when I tried to reproduce the behavior in skirmish mode, the game reported that the rear armor applied negative damage reduction!

negative_armor.png (24.74 KiB) Viewed 4472 times

Can somebody explain to me how this works? As it is, I don't have a feel for which matchups are winnable.

[BenjaminFromPavonis]

Hey Starstrider. The negative damage value under the armor absorption indicates that this hit was a critical hit. As you can see the negative value is added to the damage. This was pretty unclear so I have added some CRIT text that will appear when this happens in the future.

As for how the damage is calculated, The damage in the ship designer is an estimate as damage is not fixed for anything except maybe plasma.

Projectile damage, including missile, varies with the closing velocity. 0.5mv^2, so a change in the "v" has a huge impact.
Laser damage varies by distance, and by armor thickness.

IIRC, projectile damage in the designer uses the muzzle velocity (or missile DV) as the example velocity when estimating damage. So it's basically only true in the situation where the shooter and target are motionless (and a missile moves in a straight line and has time to burn all its fuel before hitting the target).

[Starstrider42]

Thanks for the reply. To be clear, I wasn't expecting the damage to be fixed, I just wasn't expecting a factor of 5 difference.

However, I don't see how impact speed could be the explanation for what I'm seeing. Of the samples I listed, the largest (5.8) was for a missile that hit the ship at roughly right angles to the ship's velocity vector at medium range. The smaller values were for a head-on collision after the missiles had expended their fuel. If it were just a matter of speed, I'd expect the damage to be larger than nominal in the second case.

EDIT: In my initial post, I didn't make clear that all of the hits to the target's rear reported negative armor -- five hits in a row. I would have expected crits to be, you know, rarer.

[Starstrider42]

I think I've figured out part of what's going on here. The "80% damage to armor" should actually be read as "20% regular damage, 80% chipping". The reported damage is just the regular 20% (expect 6.1, which is slightly higher than observed), and the degradation of the armor itself is not reported (though it seems to contribute to the negative damage reduction on later shots). Is that basically correct?

It's a bit surprising to see missiles rely on Battletech-style armor removal, especially given how TI strives to be realistic in many other respects. Maybe chipping damage could be added to the damage report?