• Members 2 posts
    May 16, 2018, 4:41 a.m.

    So I was looking at the Kirovets-1 specifically but idk if this affects other tanks. To my understanding you calculate relative armor thickness by dividing the nominal thickness by cosine of the armor angle. The upper plate is 140 mm thick at 60 degrees which gives effective thickness of 280, but down to 266 because of 5% AP normalization. However, the app shows the upper plate armor being only 243 mm thick. The case is similar with the lower plate, where my math shows it should be 171 mm thick but it's only 156. I might be wrong in my math or something, I just wanted to know if there's some factor I'm missing or if the app is bugged or something.

  • May 16, 2018, 3:28 p.m.

    The reason is that the normalization applies to impact angle and not as a percentage to effective thickness. It is measured in degrees and not in percentage. So in your example 5 degrees normalization applies to 60 degrees impact angles which decreases angle to 55, then the effective armor is calculated as 140mm / cos(60-5) ~= 244mm. Here is a link to penetration mechanics explained wiki.wargaming.net/en/Battle_Mechanics

    Armor Inspector also takes into account the tank you're shooting from. Which means the impact angle depends also on the height of the shooting tank and distance. Even if the upper plate is angled at 60 degrees higher tank at close distance can hit it in less than 60 degrees. Take a look at these examples:

    Here is AMX 50/100 shooting at upper plate of Kirovets at 12m and the impact angle before normalization is 53 degrees. Notice also that the bottom part of lower plate can't be penetrated due to ricochet
    i.imgur.com/lUUQGtc.png

    And here is the UDES 03 is trying to hit the same spot. Just because the tank is much lower the impact angle is about 59 degrees.
    i.imgur.com/UFJ2Aoa.png

  • Members 2 posts
    May 16, 2018, 10:24 p.m.

    Oh okay, I don't know where I got in my mind that normalization is 5% and not 5 degrees so this makes sense. And I'm aware of the height factor, that's why I set the impact angle to exactly 60° when looking at the relative thickness of upper plate and lower plate even if those aren't common heights to be shot from. Thank you!