Can anybody explain armor penetration from aircraft on ground units?

[ww2planes]

Good day everyone,

I’m just reaching out to see if anybody can explain the armor penetration calculations for air to ground pounding.

After watching my entire team get wrecked by Yak 9T/9Ks, I decided to check the replay and noticed the rounds were coming in EXTREMELY steep and still penetrating. I know that overmatch is a thing for ground shells but, at least from what I’ve been able to find, isn’t a thing for aircraft cannon rounds. So with this, I decided to compare it to other 37mm rounds available to aircraft. All shots are in the same plate of armor of 10mm.

So first, the Yak 9T with the AP-T shell



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Secondly, the P-63A-5 with the AP-T shell


Same angle and range as the Yak 9T AP-T

What it takes to penetrate at the same range

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Finally, the Hs-129 with 37mm HVAPT


Same angle and range as the Yak 9T AP-T

What it takes to penetrate at the same range

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Thanks for the explanation (if anybody can). I did calculate this out and the raw material thickness at 73* is 34mm (as the game states when checking it).

[JeruzalemisREAL]

If we apply tank shell physics to this, the difference is its ability to penetrate angled armor plates. The difference between apcr, ap, apcbc for example. Ap is better at penetrating flat armor, but worse at angled armor. While an apbc apcbc are better at penetrating angled armor, and armor over distance.

Apcr is extremely bad at penetrating angled plates.

So, using above examples, the yaks use apbc if i remember correctly. It are literally tank shells. The german one has high pen, but is similar to apcr, bad angle pen.

The american 37mm has naturally low penetration, so it cant be used against alot. Maybe from a steep angle and at closer ranges. 37mm of pen is alot less to work with than 71mm. Roofs are usually around ~20mm.

The amount of damage is influenced by its ability to penetrate, size of shell, and post pen inertia. If a shell with 60mm pen goes through 55mm of armor, it loses alot of inertia. Spalling is less lethal.