FWs Durabillity

[Pursuivant]

Originally Posted by RPS69

Actually, I will really like to see any proof of severing a wing from a 190 on reality using .50s. Wings got severed not by enemy fire itself, but by a weakening of it's structure and spars that are subjected to high pressure.

You're right, of course. It's rare that any sort of small caliber gunfire - even counting 30mm guns as "small" - directly causes structural failure.

Instead, as you point out, what happens is that the gunfire sufficiently weakens the airframe that the forces of gravity, g-forces, and air resistance take over and cause structural collapse.

If you look at combat films where an aircraft's wing fails, often you'll see a slight delay before the wing comes off. Sometimes, you'll even see the wing "fold" as it collapses. That means that the gunfire/fire just fatally weakened the wing and gravity and air pressure finished the job.

I don't know if IL2 can model progressive weakening of damaged parts. Obviously, the game models parts pulling off due to overspeed flight, but I'm not sure if the game progressively reduces the top speed and maximum G load a damaged part can sustain without failing.

For the experiments I did with the FW-190, they were mostly in level flight or making relatively low-G turns, and were never traveling at excessive speeds. So, I have no way of knowing if the FW-190's wing might have failed had it been exposed to greater stresses, assuming the game even models that sort of failure.

Originally Posted by RPS69

Also you could got the ammo rack exploded if it was simulated on il-2 at all, but it is not.

I'm pretty sure that all a hit to the 20mm cannon magazine does is trigger a "gun jammed" hit. IL2 doesn't seem to model the possibility of bullets/cannon shells exploding. To be fair, that possibility is rare, since it requires just the right circumstances for one bullet/cannon shell to make another bullet/shell explode.

Originally Posted by RPS69

190's were really sturdy for their time. Much more so than a 109.

Of course the men who flew the FW-190 thought that it was a tougher plane than the Bf-109! The FW-190 was heavier (3,200 kg for the FW-190A-8 vs. 2,247 kg for the Bf-109G-6) and the basic airframe was designed 5 years after the Bf-109's (1937 vs. 1933) giving it at least a "generation" of progressive improvements in airframe construction.

The real question is whether the FW-190 was any tougher than aircraft of equivalent quality of construction, designed in the same year, and with roughly equivalent mass. For example, should the FW-190's AIRFRAME be any tougher than that of the P-51 D (designed 1939/40, 3,465 kg empty mass) or the P-40E (designed 1938, 2,753 kg empty mass)?

Unless you have a novel structural design which was famed for its structural strength or weakness - like the geodesic wing and fuselage structure of the Wellington or the delamination problems that some of the LaGG-3 series suffered - then really all you can do is base a plane's ability to absorb punishment on its year of production and its empty mass.

Perhaps divide by the number of engines and/or omit the mass of the engines as well.

Pilot reports of relative combat durability of their aircraft have to be read skeptically, because they're based on the accounts of the men who survived and came back to tell the tale. If a plane was well-liked by its crew, they were likely to overlook its lesser faults and sing its praises. If they disliked the type, they were likely to overlook its merits.

Also, unless you're reading the reports of a test pilot or an engineering commission, where the writer(s) had a chance to examine multiple different aircraft, the writer - even if he's an experienced combat veteran - might not necessarily be in the best position to make comparisons.

Originally Posted by RPS69

Even so, on the popular plane lists, it is the one that suffers more from single damage. It becomes almost impossible to land safely after any single shot on it's wings.

I agree, this is another way that the FW-190 is messed up. Just a handful of .50 caliber bullets scattered across the wings will trigger the heavy damage texture. That seems excessive considering that each .50 caliber bullet is only going to make a thumb-sized to fist-sized hole. (huge by human standards, but less impressive scattered across several square meters of space).

In some ways it seems like it's far too easy to damage the FW-190, in other ways it seems to be invulnerable.

Too weak: Far too vulnerable to having minor wing or fuselage damage turn into serious damage. Probably a bit too vulnerable to having control surfaces shot off/seriously damaged. Perhaps a bit too vulnerable to fuel tank fires (but no more vulnerable than equivalently equipped planes in the game).

Too easy to snap the fuselage due to damage (but this is IL2's method of modeling fatal fuselage damage that renders the plane unflyable. Since IL2 can't make airframes bend or shake, it breaks them instead.)

Too strong: Seems quite difficult for heavy damage to the wing (at least from .50 caliber guns) to convert to fatal damage - either directly or by causing structural failure under G-loads. Probably far too difficult to start an engine fire. Possibly too difficult to seriously damage/destroy vertical stabilizer.

Just right: Armor modeling, cockpit/crew hits, hydraulic failure which causes landing gear to begin to extend. Engine durability (excluding fires).

Missing/Not modeled (AFAIK): Potential "critical hit" to loaded 20mm cannon magazine can cause secondary explosion sufficient to instantly separate the wing.

[RPS69]

Originally Posted by Pursuivant

I don't know if IL2 can model progressive weakening of damaged parts. Obviously, the game models parts pulling off due to overspeed flight, but I'm not sure if the game progressively reduces the top speed and maximum G load a damaged part can sustain without failing.

Very good question. It does model it with a heavier load, but I don't know if it applies to damaged air frames too.

Now, you could see a lot of guncams of zeros or Ki43 planes braking wings, but it is very difficult to find one of an anton doing it.

Also, they will rarely aim at a wing, they will fire to the bulk of the plane. Wing shots are always done while diving on an unexpected foe, not from dead six. And guncams of diving shots are extremely rare to find. Specially because they don't show the enemy plane. That kind of shot is always a deflection shot.

I'm pretty sure that all a hit to the 20mm cannon magazine does is trigger a "gun jammed" hit. IL2 doesn't seem to model the possibility of bullets/cannon shells exploding. To be fair, that possibility is rare, since it requires just the right circumstances for one bullet/cannon shell to make another bullet/shell explode.

I don't know how rare it was, but ages back, in the beginnings of il-2, they invited a former German fighter pilot to test the sim, and when he find himself being fired at, the first thing he did, was emptying his magazine, even before trying to evade it's foe. Everybody was confused why he was doing that, and he clearly explained that it was for avoiding fatal hit on live ammo. He didn't know that it wasn't simmed.

Of course the men who flew the FW-190 thought that it was a tougher plane than the Bf-109! The FW-190 was heavier (3,200 kg for the FW-190A-8 vs. 2,247 kg for the Bf-109G-6) and the basic airframe was designed 5 years after the Bf-109's (1937 vs. 1933) giving it at least a "generation" of progressive improvements in airframe construction.

Actually, if you can believe the tales on osprey book aces of the FW on the eastern front, the first test the pilots themselves made was putting the 190 on a steep dive, and, after landing, count the lost rivets on the airframe.
The tale states that to their surprise, the count was zero.

The real question is whether the FW-190 was any tougher than aircraft of equivalent quality of construction, designed in the same year, and with roughly equivalent mass. For example, should the FW-190's AIRFRAME be any tougher than that of the P-51 D (designed 1939/40, 3,465 kg empty mass) or the P-40E (designed 1938, 2,753 kg empty mass)?

Tougher wings, I don't know, but smaller, for sure! Also, it's ailerons control system, was far better and sturdier than any other plane of it's time. It also helped to build stronger wings because of this particular detail.

Also, unless you're reading the reports of a test pilot or an engineering commission, where the writer(s) had a chance to examine multiple different aircraft, the writer - even if he's an experienced combat veteran - might not necessarily be in the best position to make comparisons.

Already assumed before posting

I agree, this is another way that the FW-190 is messed up. Just a handful of .50 caliber bullets scattered across the wings will trigger the heavy damage texture. That seems excessive considering that each .50 caliber bullet is only going to make a thumb-sized to fist-sized hole. (huge by human standards, but less impressive scattered across several square meters of space).

It doesn't need a handful. Sometimes even a singe shot will do the trick. Tested it with the arrows enabled.

In some ways it seems like it's far too easy to damage the FW-190, in other ways it seems to be invulnerable.

Tough, yes, invulnerable, no way. Pick 8 B17s on quick mission. at 2000m. Not historically accurate, but funnier to do. Try to down more than four, and tell me how invulnerable it is to .50s fire. It is really nice to try it.

You will suffer a lot of damage, and of different sorts.
Try the same thing with different planes, and you will have an idea which planes have weak points when YOU are flying them.
Still, american .50s are really a bad weapon to down B17s!

Keep the arrows on.

[Pursuivant]

Originally Posted by RPS69

Also, they will rarely aim at a wing, they will fire to the bulk of the plane.

Agreed, but if you get your deflection wrong while aiming at the fuselage, your bullets can go through the wings.

Originally Posted by RPS69

I don't know how rare it was, but ages back, in the beginnings of il-2, they invited a former German fighter pilot to test the sim, and when he find himself being fired at, the first thing he did, was emptying his magazine

That's good evidence that the more experienced German pilots knew of the "bug," so it must be more common than I assumed.

The reason I called out bullets/shells exploding bullets/shells as being rare is that in order to get a secondary explosion, you need to have an explosive bullet that hits the propellant or explosive charge, or a direct hit on the primer within the bullet, to make it detonate. Otherwise, the bullet/shell hit just tears up the other bullet/shell, which just causes a stoppage.

Also, with a typical aircraft ammo belting, you're only going to have a fraction of bullets/shells which are APE (rarely HE). That means you've typically got a 20%-33% chance that any bullet that hits ammo will be APE, and a 25-33% chance that the bullet/shell it hits will be APE.

So, low odds, but higher than getting hit by lightning or winning the lottery.

But, packing all your bullets/shells into a magazine (like FW-190's cannon shell magazine) will increase the chance that an APE bullet will hit something that causes a secondary explosion, so the odds go up a bit.

To simplify things, lets say there's a 10% chance that any hit to a magazine by an explosive bullet will cause a secondary explosion, multiplied by the percentage of HE bullets in the magazine. With 25% explosive rounds for both attacker and target, that works out to a 0.625% chance that any given bullet hit to a magazine will cause a secondary explosion.

Basically, a lucky hit rather than a certainty, even if you're an amazing shot.

Originally Posted by RPS69

Actually, if you can believe the tales on osprey book aces of the FW on the eastern front, the first test the pilots themselves made was putting the 190 on a steep dive, and, after landing, count the lost rivets on the airframe.
The tale states that to their surprise, the count was zero.

The factors that affect airframe durability are: design quality, construction quality, & quality of materials.

Early war German aircraft were beautifully constructed, which is why monthly aircraft production totals were low(ish). The same could be said for pre-war/early war aircraft constructed by other advanced economies, as well as many prototypes.

Massively mass-produced aircraft, especially those constructed from inferior materials, had inferior - or at least uneven - construction. Pilots of the era will tell you that no two aircraft flew exactly the same, even if they came off the same assembly line.

Giving the FW-190A the benefit of the doubt, I'd call it superior in terms of design, superior in construction quality, but average in terms of materials (at least for much of the war). Later war versions were probably only average in construction quality.

By contrast: P-51D = superior design, average construction quality (Rosie the Riveter was highly motivated, but she was new to the job), with average to superior materials. LaGG-3 = Superior design (precursor to the well-loved and rugged La-5), average to poor construction quality (and quite variable!), average to poor materials.

Originally Posted by RPS69

Tougher wings, I don't know, but smaller, for sure! Also, it's ailerons control system, was far better and sturdier than any other plane of it's time.

Control system =/ control surface area. The FW-190 should be a bit more resilient vs. aileron control damage. Control surfaces are a different story, since they're fabric covered.

The game doesn't distinguish between fabric-covered surfaces vs. surfaces with a skin of some solid material like wood or aluminum. Fabric-covered surfaces shouldn't trigger bullet/cannon shell explosions, should be much more vulnerable to fire, and to the effects of nearby internal explosions. Wood or steel frame with doped canvas construction should also have fewer overall "hit points" than for monococque construction.

Fabric covered control surfaces should be slightly less responsive at high speeds, and more prone to damage due to overspeed. (The fabric could deform or tear under stress.)

Originally Posted by RPS69

It doesn't need a handful. Sometimes even a singe shot will do the trick. Tested it with the arrows enabled.

This a problem common to all aircraft in the game. IL2 damage textures are merely "artist's interpretations" of actual damage results. With Arcade Mode on, you can get some really strange results. For example, in a some cases, the damage textures will actually show more holes in the plane than the actual number of actual bullets that hit it!

I think you could make a good case that the damage threshold required to trigger any sort of damage to fuselage, wings, tail or control surfaces, for all planes, should be considerably higher for .30 caliber or .50 caliber bullets. Those weapons were fine for killing people, damaging engines and starting fires, but were never intended to blast vehicles apart.

But, there also needs to be some degree of progressive weakening of damaged parts so even .30 caliber bullets can make a plane fall apart if it subsequently pulls extreme Gs or goes overspeed.

Originally Posted by RPS69

Tough, yes, invulnerable, no way. Pick 8 B17s on quick mission. at 2000m. Not historically accurate, but funnier to do. Try to down more than four, and tell me how invulnerable it is to .50s fire. It is really nice to try it.

You'll get no argument from me, but it's a matter of how you die. I've flown this sort of mission dozens of times over the years and generally end up with a dead/dying engine or pilot. Less commonly a flaming fuel tank or chewed up wing that keeps me from keeping up with the bomber formation. Its very unusual to get a wing failure, however.

Originally Posted by RPS69

Still, american .50s are really a bad weapon to down B17s!

That's the thing that US 0.50 caliber fanboys forget. .50 caliber/12.7 mm guns suck against any sturdily-built medium to heavy bomber.

The US military standardized on the M2 as their preferred aerial weapon because it was their most reliable weapon, because it simplified supply chain problems, and most importantly, because US pilots were almost always on the offensive, flying long range missions (where ammo quantity is as important as weight of fire) where the opposition was usually enemy fighters.

By contrast, nations whose air forces had to play defense against medium or heavy bombers (read: everybody except the US), or who wanted effective "tank buster" aircraft, quickly learned that the 20 mm or 30 mm cannon was the preferred tool for the job.

For bomber interceptors, the US got the message, too, which is why planes like the F6F-5N, P-61 & F7F were armed with cannons.

[gaunt1]

Actually, the .50 was nothing specatacular even against fighters. What made them effective, the number of them. 6-8 such machineguns were more than enough, but the cost was lots of weight.

[majorfailure]

Originally Posted by RPS69

Still, american .50s are really a bad weapon to down B17s!

It is not the weapon of choice - but one good, concentrated burst to vulnerable areas (B-17:fuel tanks, engines, pilot(s))-does still hurt or kill - even fat cars.

Originally Posted by gaunt1

soviet 12.7 is underpowered currently.

My feeling is different, if you have a stable gunnery platform, the UB is IMHO on par with other HMGs - you can make quite a mess of German planes with only one UB the usually give you in a YAK. Yak3 has two UB, even better, MiG-3 too - and there they suck balls, and I think it is because MiG-3 is so unstable and the white tracers are not very useful for correcting aim, too.

[gaunt1]

Originally Posted by majorfailure

you can make quite a mess of German planes

You can make a mess of german planes with just about everything. They are so weak. Test it against tougher planes.

[Pursuivant]

Originally Posted by gaunt1

You can make a mess of german planes with just about everything. They are so weak. Test it against tougher planes.

I wouldn't call the German planes "weak." Most of them seem to be more or less right - but with odd inconsistencies.

What might be an issue is that the basic DM for many of them is OLD, in some cases dating back to the original IL2 Sturmovik game. There are probably a lot of simplifications and inconsistencies still lurking there, waiting to be bug stomped.

[RPS69]

Just find some time to spend testing .50's on lots of planes.

I used a B25 rear gunner, and each time placed a different plane at it's rear on the runaway.

Planes I tested that won't break a wing:

FW190 A&D
Bf110
P51
P47
P38
F4U1
F6F
F4F
F2A

Planes that will break it:

Bf109
A6M
Spitfire
Tempest
P40
P39
La5
Yak9

I also tested the other thread beginner theory about 190 no taking fire when hitting their engine with .50's.

190 Do take fire, but it is represented on the cabin.
All other airplanes will also take fire, but it will be showed on different places, not necessary on their engines.

So... it is not a 190 issue.

Now, if you hit the wing, even the AI at some point, on any of those planes, will lost control of it.
Also, 109's do break their wings with .50's, but doing so on a moving target it is much more difficult than when stationary. The amount of well placed and consecutive shots are difficult to achieve(as the P40 or spitfire)

Only the Zero it's much more fragile to the .50's. A well placed burst will break it easily.

If someone is interested, this is the test mission

[MAIN]
MAP SandsOfTime/load.ini
TIME 12.0
CloudType 0
CloudHeight 1000.0
player r0100
army 1
playerNum 0
[SEASON]
Year 1940
Month 6
Day 15
[WEATHER]
WindDirection 0.0
WindSpeed 0.0
Gust 0
Turbulence 0
[MDS]
MDS_Radar_SetRadarToAdvanceMode 0
MDS_Radar_RefreshInterval 0
MDS_Radar_DisableVectoring 0
MDS_Radar_EnableTowerCommunications 1
MDS_Radar_ShipsAsRadar 0
MDS_Radar_ShipRadar_MaxRange 100
MDS_Radar_ShipRadar_MinHeight 100
MDS_Radar_ShipRadar_MaxHeight 5000
MDS_Radar_ShipSmallRadar_MaxRange 25
MDS_Radar_ShipSmallRadar_MinHeight 0
MDS_Radar_ShipSmallRadar_MaxHeight 2000
MDS_Radar_ScoutsAsRadar 0
MDS_Radar_ScoutRadar_MaxRange 2
MDS_Radar_ScoutRadar_DeltaHeight 1500
MDS_Radar_HideUnpopulatedAirstripsFromMinimap 0
MDS_Radar_ScoutGroundObjects_Alpha 5
MDS_Radar_ScoutCompleteRecon 0
MDS_Misc_DisableAIRadioChatter 0
MDS_Misc_DespawnAIPlanesAfterLanding 1
MDS_Misc_HidePlayersCountOnHomeBase 0
MDS_Misc_BombsCat1_CratersVisibilityMultiplier 1.0
MDS_Misc_BombsCat2_CratersVisibilityMultiplier 1.0
MDS_Misc_BombsCat3_CratersVisibilityMultiplier 1.0
[RespawnTime]
Bigship 1800
Ship 1800
Aeroanchored 1800
Artillery 1800
Searchlight 1800
[Wing]
r0100
r0101
[r0100]
Planes 1
Skill 1
Class air.B_25J1
Fuel 100
weapons default
[r0100_Way]
TAKEOFF 14379.60 26740.23 0 0 &0
NORMFLY 13827.45 26741.52 500.00 300.00 &0
[r0101]
Planes 1
Skill 1
Class air.FW_190D9
Fuel 100
weapons default
[r0101_Way]
TAKEOFF 14379.60 26740.23 0 0 &0
NORMFLY 13836.59 26750.66 500.00 300.00 &0
[NStationary]
[Buildings]
[Bridge]
[House]

[Pursuivant]

Originally Posted by RPS69

Just find some time to spend testing .50's on lots of planes.

Brilliant! A very clever method of testing.

Originally Posted by RPS69

I used a B25 rear gunner, and each time placed a different plane at it's rear on the runaway.

B-25 rear guns are equal to those of most other US medium or heavy bombers - twin .50 calibers - so good choice.

Originally Posted by RPS69

Planes I tested that won't break a wing:

Good data. But, two minor complaints.

How many bullets does it take to break the wings of the planes whose wings will break?

Shooting at planes on the ground also means that its wings are under exactly 1 G of positive pressure for the entire period. Assuming that IL2 models it, that means that there's no way to test whether a wing will fail due to damage when subjected to G loads.

Further experiment idea: Try the same thing with the G4M "Betty" and see how well suspect planes fare against a 20 mm cannon. If you can't eventually break wings with a 20 mm cannon, that means there's a serious DM problem.

For the planes whose wings can't be broken off by .50 caliber fire, it seems odd that the P-40 and the Tempest are on the list. Both were regarded as being quite rugged.

Originally Posted by RPS69

I also tested the other thread beginner theory about 190 no taking fire when hitting their engine with .50's.

190 Do take fire, but it is represented on the cabin.

That might just represent a fuel tank fire, since the FW-190 is angled up when its on the ground, possibly allowing bullets to hit just below the engine so they pass through the fuel tank.

Originally Posted by RPS69

All other airplanes will also take fire, but it will be showed on different places, not necessary on their engines.

Again, is this due to actual engine fire, or due to hits to the fuel tanks?

Originally Posted by RPS69

Only the Zero it's much more fragile to the .50's. A well placed burst will break it easily.

This seems to be realistic. There are many reports of US pilots causing Zeroes, especially the A6M2 series, to break up in midair using just .50 caliber bullets. But, that might just be wing tanks exploding.

[Janosch]

I took tail gunner shots from an Il-2 (apparently 12,7 mm bullets) on my Fw-190 A6 wing. The left wingtip/emblem area looked very, very ugly - bullet holes and large dark splotches. With such damage, fighting is pretty much out of the question, but the plane is far from unflyable, and landing requires just a bit more caution than usually, so that the plane doesn't roll left when you least expect it! My wheels touched down roughly at 45% of standard grass runway length, and the plane came to full stop at 96%, give or take a few percent. I'd say that's good enough for a damaged plane. In lab conditions, the landing distance needed is naturally shorter.

Originally Posted by Pursuivant

If a plane was well-liked by its crew, they were likely to overlook its lesser faults and sing its praises.

Or maybe there were no faults at all, and they were very musical people. I haven't come across a Focke Wulf - Lied, though