Yak-9T - incredible firepower (or maybe incredible tank's lack of armor?)

[Igo kyu]

There are three types of armament that could be used from the air against tanks. Rockets, if they hit would be devastating, because of the relatively huge explosive content. Bombs would be moreso, but they would have to detonate on impact and that would very probably destroy the attacking aircraft, so that that would be unlikely to happen. The third thing is guns, but there are two types of warheads here, solid shot, and high explosive. High explosive wouldn't get through the armour. Solid shot might, but that is much less effective as an air to air weapon. Most of the guns in IL*2 fire high explosive air to air rounds, it is after all a flight simulator, but those would have been ineffective against tanks in the real world.

[JtD]

There are explosive AP rounds.

Aircraft weapons were very well capable of destroying tanks, the biggest difficulty was to hit the target. And that was easiest with guns.

One can also be sure that a single hit of say a 100g projectile of a 20mm cannon penetrating armour and then exploding inside the tank would not always destroy the tank. That's something not even a ~6kg round of 75mm cannon would manage all the time. But, nonetheless, against medium tanks say up to Pz IV size, even the small 20mm cannons did occasionally work as tank killers, provided they had a high muzzle velocity and a heavy projectile with decent AP qualities. The Hispano for instance had all that.

[IceFire]

I'm just wondering if there is no problem at all here. Sure in a testing environment you can wax a dozen medium tanks with a high angle 37mm shot. I'm not sure if this is an issue or not... in real life you'd likely be dealing with small arms fire and maybe mobile AAA making this sort of repeated attack against a formation of tanks somewhat unrealistic.

[gaunt1]

Please, read this:

http://operationbarbarossa.net/Myth-...hbusters4.html

"During WWII, the large majority of aircraft attacking tanks with aircraft mounted weapons used 20mm cannon or simply HMGs. These include aircraft such as the Supermarine Spitfire, Hawker Typhoon, Hawker Tempest, De Havilland Mosquito, most Ilyushin Il-2s and Il-10s (some had 37mm cannon), Yakovlev Yak-7/9, Petlyakov Pe-2/3bis, Lockheed P38 Lightning, North American P51 Mustang, and the Republic P47 Thunderbolt. The average 20mm cannon with standard ammunition had great difficulty penetrating the 12-15mm top armour on the Pz IV H, and almost no chance against the 16mm top armour on the Panther and the 25mm top armour on the Tiger I, even if they managed to hit them! The reader should also bear in mind that on average the strike angle of cannon shells on the top of AFVs was usually in the region of 30 to 60 degrees, because aircraft could not attack vertically downwards (the Ju 87 Stuka came closest to this ideal attack angle, which also dramatically increases the accuracy of any air launched ordnance). In general 20mm cannon only inflicted superficial damage on even light tanks, with the most severe damage being penetrations through the top engine grill covers and damage to the engines."

"German fully tracked AFV losses on the East Front from 1941 to 1945 amounted to approximately 32 800 AFVs. At most 7% were destroyed by direct air attack, which amounts to approximately 2 300 German fully tracked AFV lost to direct air attack, a portion of which would be lost to other aircraft types such as the Petlyakov Pe-2. From 22nd June 1941 to war's end, 23 600 Il-2 and Il-10 ground attack aircraft were irrecoverably lost.(21) Whatever these aircraft were doing to pay such a high price it wasn’t destroying German tanks. If that was there primary target, then over 10 Il-2s and Il-10s were irrecoverably lost for every German fully tracked AFV that was completely destroyed by direct air attack on the East Front during WWII.
"

WW2 aircraft guns had low armor penetration capability. The GAU-8 Avenger, even with uranium rounds is only capable of penetrating 69mm @ 500m. (only 38mm @ 1000m) The Hispano or the VYa is nowhere near to this monster gun.

[Furio]

Originally Posted by gaunt1

Please, read this:

http://operationbarbarossa.net/Myth-...hbusters4.html

.

I read several pages of this myth-buster. Overall, I strongly believe that over claiming was enormous, and not only in aircraft versus tank. However, this same myth-buster gives some suspect numbers and makes some unsubstantiated claims. This, for example: “In addition the RAF and USAF had given the Soviets critical air superiority for the first time (in 1944)”. No comments or details are given to this piece of “undisputable truth” that sounds to me as a simple nonsense, reducing the accountability of the whole analysis to the typical low level of web literature.

As off topic it may sounds, this discussion is probably pointing to the one of the most important point of any “realistic” simulation. If true combat effectiveness would be really implemented, we should expect our kills (of anything: tanks, aircraft, vehicles, ships, anything) to be reduced by a factor of probably ten. On the contrary, the probability to end our simulated career as KIA would be augmented by the same rate. Not very fun, I think…

[gaunt1]

As off topic it may sounds, this discussion is probably pointing to the one of the most important point of any “realistic” simulation. If true combat effectiveness would be really implemented, we should expect our kills (of anything: tanks, aircraft, vehicles, ships, anything) to be reduced by a factor of probably ten. On the contrary, the probability to end our simulated career as KIA would be augmented by the same rate. Not very fun, I think…

Yes, I completely agree. In fact, I also dont want it to be changed. (especially because I love to fly IL-2/10) I just pointed out on that in RL, things were different.

[Igo kyu]

Originally Posted by JtD

There are explosive AP rounds.

Aircraft weapons were very well capable of destroying tanks, the biggest difficulty was to hit the target. And that was easiest with guns.

One can also be sure that a single hit of say a 100g projectile of a 20mm cannon penetrating armour and then exploding inside the tank would not always destroy the tank. That's something not even a ~6kg round of 75mm cannon would manage all the time. But, nonetheless, against medium tanks say up to Pz IV size, even the small 20mm cannons did occasionally work as tank killers, provided they had a high muzzle velocity and a heavy projectile with decent AP qualities. The Hispano for instance had all that.

The thing with armour piercing rounds is that if the round hits the armour, it either bounces off, breaks up, or goes through. If the round breaks up, it won't go through because it's no longer a single mass but a bunch of smaller masses. When a round goes through armour, then the armour has broken up and the projectile retains most of the kinetic energy it had when it first hit the armour, so it does a lot of damage from that, if it gets into the engine comparment probably breaks the engine. There may be an explosive payload, but to do damage there doesn't really need to be.

[JtD]

I hope that you are aware that by far the most WW2 AP rounds were explosive rounds. For a reason. For instance, rounds having pierced armour do not retain most of their energy, unless the armour wasn't worth mentioning in the first place. Rounds without explosives usually were some hard core rounds (tungsten for instance), which offered superior penetration at the expense of damage capacity. In case of aircraft guns this often was a popular trade off, since the small calibre guns otherwise wouldn't penetrate at all.

For comparison, the very good German 30mm tungsten core round carried only 75% the energy of the standard AP round, at the muzzle. Further away, even less. It had far better penetrating power, more than two times as much at 500m, but if both rounds got through, the standard round would wreck far more havoc.

[Pursuivant]

Originally Posted by JtD

One can also be sure that a single hit of say a 100g projectile of a 20mm cannon penetrating armour and then exploding inside the tank would not always destroy the tank.

An AP projectile penetrating armor sprays red-hot or molten fragments of metal around a very small space. Those fragments ricochet and start fires. You DON'T want to be in that space. While a 20-30 mm projectile won't usually make the tank blow up or burn, it will damage the engine (if it penetrates the deck armor or ventilator grilles) OR kills or injures part of the crew (if it penetrates the turret or hull).

Even if it doesn't catch on fire, a tank with a badly damaged engine and/or a dead/seriously wounded crewman is going to retreat. Alternately, the crew might bail out, either because the tank can no longer move or because the drivers are dead, or on the reasonable assumption that more bad things are about to come their way.

In any case, the tank is as good as "dead" that day, even if the mechanics can later wash out the blood, fix the engine and patch the armor.

A simple fix to the ground vehicle damage model in IL2 would to be have three damage states: Undamaged, Immobilized/Partially destroyed (representing a crew kill or actual mobility kill) and the current damage model "Brewed up"/completely destroyed. No new damage textures are needed for Immobilized - the vehicle just stops moving.

This intermediate damage state is important, since the disabled tank remains a target for further attacks. That means that you and your allies waste ammo on a "dead" foe.

Pictures of knocked out WW2 AFV frequently show multiple penetrations. Example here:

http://i73.photobucket.com/albums/i2...ps736b6ffd.jpg

[Pursuivant]

Originally Posted by JtD

I hope that you are aware that by far the most WW2 AP rounds were explosive rounds.

Actually, for much of the war, tanks mostly carried standard AP rounds. Ammo like HEAT/APEX or HESH were later war innovations and they were often in short supply, as were standard AP rounds with tungsten penetrators.

As I mentioned in my previous post, a simple AP round penetrating armor generates plenty of heat and shrapnel even without the benefit of an explosive charge. Obviously, APEX or its ilk are better, and tungsten core penetrates better, but ordinary AP is plenty deadly against armor.

Conversely, soft vehicles sometimes fared better when hit by AP rounds, since the round might penetrate without fragmenting (e.g., going through the wood and canvas sideboards of a truck) or produce minimal fragments (e.g., punching through the sheet metal of a car's body). Very soft targets, like canvas or flesh, might not even trigger HE rounds.

This also holds true for cannon shells against early war canvas-covered aircraft like the Hurricane. AP rounds would just punch a small hole in the canvas without weakening the plane's structure, and HE rounds might blow through without exploding.