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.