Damage Model Bug Stomping - Part 2

[Furio]

Once, I was shot down by a couple of bullets in the nose of my plane. Tac -tac, and the engine began immediately to emit creaking and squeaking sounds, losing power and stopping after a couple of minutes… The gun was an Mg15 (Stuka gunner) and my plane an armoured Il2… Hardly realistic.

In another occasion, while flying with a cannon armed La5, I set on fire a PZL P11. It burned furiously, and went ahead for a loooong time flying excellent evasive manoeuvres without any hint of diminished performances (or pilot’s cooking).

I think sometimes strange things happen, and are almost certainly result of random errors, having nothing to do with damage models. I think that reports about single events are of little value. What we need are consistent experiments, repeatable by others, like a sort of peer review. Pursuivant demonstrates that can be done, and that results are sometimes surprising.

I believe that further test will bring more surprises. And also think that Il2 remains a fantastic game, still a lot of fun after so many years, a monument to original developers and to the continuing work being done today.

[majorfailure]

Originally Posted by Furio

Once, I was shot down by a couple of bullets in the nose of my plane. Tac -tac, and the engine began immediately to emit creaking and squeaking sounds, losing power and stopping after a couple of minutes… The gun was an Mg15 (Stuka gunner) and my plane an armoured Il2… Hardly realistic.

Can get even worse. PK from Bf110 rear gunner in an IL-2, that's as impossible as it gets.

Originally Posted by Furio

I think sometimes strange things happen, and are almost certainly result of random errors, having nothing to do with damage models. I think that reports about single events are of little value. What we need are consistent experiments, repeatable by others, like a sort of peer review. Pursuivant demonstrates that can be done, and that results are sometimes surprising.

Yes. Totally agree. Once is almost never. And data is always better as impressions&conjecture, I think I inadvertently proved that with my last post.

Originally Posted by Furio

I believe that further test will bring more surprises. And also think that Il2 remains a fantastic game, still a lot of fun after so many years, a monument to original developers and to the continuing work being done today.

I'll drink to that. Cheers!

[Janosch]

Originally Posted by majorfailure

Can get even worse. PK from Bf110 rear gunner in an IL-2, that's as impossible as it gets.

So a pilot can die if hit by a machine gun? Madness!

[Pursuivant]

Originally Posted by Furio

The gun was an Mg15 (Stuka gunner) and my plane an armoured Il2… Hardly realistic.

I beg to disagree. The IL2's armor makes it very tough, but not invulnerable. There are gaps in its armor which you can exploit.

It is quite vulnerable to hits to the oil cooler and coolant radiator. The sort of damage you describes perfectly matches the effects of a hit to either of those.

Additionally, there are gap in the armor where the exhaust stacks emerge from the engine - so a hit there will quickly stop the engine.

Originally Posted by Furio

In another occasion, while flying with a cannon armed La5, I set on fire a PZL P11. It burned furiously, and went ahead for a loooong time flying excellent evasive manoeuvres without any hint of diminished performances (or pilot’s cooking).

The PZL P.11c is one of the worst modeled planes in the game. Only the Me-323 is worse. While my tests can't test for effects on crew (other than death, injury or bail-out), it wouldn't surprise me in the least if the modeling for the P.11c doesn't include instructions that cause fire damage to damage the pilot.

That said, the P.11c had the unusual ability to jettison the fuel tank in event of a fire. Realistically, if you're in a burning P.11c, you dump the fuel tank and try to glide away from the fight.

Originally Posted by Furio

I think sometimes strange things happen, and are almost certainly result of random errors, having nothing to do with damage models.

Occasionally, I'll load up the game and discover that parts that broke before refuse to break, or are harder to break. There's some randomness deliberately built into damage models - and there should be - but occasionally I think that there's just an error in the program.

Originally Posted by Furio

I think that reports about single events are of little value. What we need are consistent experiments, repeatable by others, like a sort of peer review.

Speaking of which, I welcome peer review. Don't just take my word about damage results, please try to reproduce them!

[Pursuivant]

Originally Posted by majorfailure

Can get even worse. PK from Bf110 rear gunner in an IL-2, that's as impossible as it gets.

Not impossible, just unlikely.

The IL2 had ~5mm of armor around the cockpit sides and just behind the canopy, plus armor glass at the front and a heavier armor plate behind the pilot's head.

At close range (i.e., 100 m or less) a 7.62mm AP bullet can punch through the side armor, even at an angle.

This thread nicely explains penetration of German 7.62mm bullets vs. armor plate and aircraft aluminum:

http://forum.axishistory.com/viewtopic.php?t=72990

[majorfailure]

Originally Posted by Janosch

So a pilot can die if hit by a machine gun? Madness!

Please. I did nowhere state it is uncommon or unconvincing that a pilot gets hit or killed by rifle caliber rounds. Only in an fully armoured canopy it is.

Originally Posted by Pursuivant

Not impossible, just unlikely.

The IL2 had ~5mm of armor around the cockpit sides and just behind the canopy, plus armor glass at the front and a heavier armor plate behind the pilot's head.

At close range (i.e., 100 m or less) a 7.62mm AP bullet can punch through the side armor, even at an angle.

This thread nicely explains penetration of German 7.62mm bullets vs. armor plate and aircraft aluminum:

http://forum.axishistory.com/viewtopic.php?t=72990

Should have been clearer at the first try. From around 150-200m, dead ahead. Through a spot were I thought there would be enough armour. And I got hit a few more times, also by Bf110 rear gunner, though not fatally. All from dead ahead. Ther is either a small gap in the armour of real IL-2, that is modeled correctly, or the armour model has a small gap.

But I think we digress at least a little. I hope I have time to do a more in detail review of test results this weekend.

[Pursuivant]

Originally Posted by majorfailure

Should have been clearer at the first try. From around 150-200m, dead ahead. Through a spot were I thought there would be enough armour. And I got hit a few more times, also by Bf110 rear gunner, though not fatally. All from dead ahead. There is either a small gap in the armour of real IL-2, that is modeled correctly, or the armour model has a small gap.

I've noticed in previous tests that there can be gaps in coverage of forward armor or armor glass. In particular, otherwise well-armored planes can be vulnerable to damage 12 o'clock high, or occasionally 12 o'clock low.

Sometimes this is realistic, sometimes there is an artificial gap due to the way that IL2 models the intersection of armor plate and armor glass ahead of the cockpit.

Looking at the armor diagrams for the IL2, I think that there is a gap in the protection for the pilot though the canopy from 12 o'clock high and from 1-2 o'clock & 10-11 o'clock level or high. After all, the canopy couldn't be armored that heavily because it had to be light enough to slide or jettison in a hurry.

Additionally, at 100-200m, a 7.62mm AP bullet might have just enough energy to punch through 5 mm of armor plate, especially if it was a head-on shot where the bullet's speed is combined with the speed of the oncoming aircraft.

But, I don't know how sophisticated IL2's armor penetration algorithms are. So, I don't know if it takes things like target speed or angle of impact into account when determining penetration or damage.