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XyZspineZyX
09-26-2003, 10:12 PM
Watching the recorded tracks that come with FB last night made me realize something that I think is more important than we think...

Not having stress limits on airframes, and thus airframe failures when you push the plane too far, will make it impossible for aircraft to behave realistically, no matter how detailed and accurate the rest of the FM is.

Why? Because with planes that can take 10+ Gs in any direction with no issue, people will ALWAYS fly EVERY PLANE *far* past what it would have done in real life, even when the other parameters are correct.

Every warbird operation manual I've read includes the phrases "prohibited manuvers: inverted loops and snap rolls" (and sometimes some others). While the only plane I've seen pull an inverted loop is the BI-1, I think we all know how often folks snap roll all over the place.

Regardless of how accurate the numbers are that we plug into these planes, we're still flying them beyond what they could really take.

That's what I realized when I was watching the 1C folks fly last night--they don't fly like that. They fly like REAL pilots (because many of them are). They push the plane, but nowhere near as far as you'll see online, because they're flying it as if it was a real aircraft with those structural limits. Maybe just out of subconcious habit, but they very definitely fly different.

Another thing that made me wonder even more if this is the root of some of our problems was comparing some of my online recorded tracks to gun camera footage.
One thing is defintiely clear--the average amount of deflection in most FB combat (far moreso online than single player) is about two or THREE TIMES as much as I ever saw in any of the footage I've collected and watched--over five hours worth, from all theaters, and both sides.

I think quite a bit of the 'uber-ness' some of the planes seem to have is due to one critical thing: we're flying them past what they could have taken. Some of them very well may have been able to pull 8 or 9-g snap turns. Once. Maybe twice. Some of them might have been able to pull out hard from a 6-700 kph dive inside of 400 m. Most of the time.

What sealed the theory for me, though, was watching a remote control glider one of my uncle's buddies built when we were up slope-soaring about a month ago. The thing was extremely light, and the main wingspar was machnied out of *lightweight aluminum*. Should have held up to anything, right?
Heh.
He pulled it out of a steep dive and the spar folded like a piece of paper. Plane went straight down like a rocket.

A lot of the planes we're flying were something in the order of multiple TONS. They didn't have that much of a buffer zone between their maximum capabilities and the point where they'd come apart. But right now, those limits don't exist, and the planes can do things no aircraft could ever do, even when the other performance figures are exactly correct.


So 1C, Oleg, please consider this. Even if it's very simple, even if it's only for the flyable planes, even if you have to make educated guesses about some of the figures--please seriously consider adding in airframe stress damage. The game desperately needs it. The original AirWarrior had it, CFS3 has it, I think EAW had it, and other, far older sims have included it because of how critical it is.

Our incredible game needs it too.

Stenciled on the side of my Dora:

"Lasst das H√¬∂llentor √¬∂ffen, es friert hier oben!"
("Leave the gates to Hell open, it's FREEZING up here!")

XyZspineZyX
09-26-2003, 10:12 PM
Watching the recorded tracks that come with FB last night made me realize something that I think is more important than we think...

Not having stress limits on airframes, and thus airframe failures when you push the plane too far, will make it impossible for aircraft to behave realistically, no matter how detailed and accurate the rest of the FM is.

Why? Because with planes that can take 10+ Gs in any direction with no issue, people will ALWAYS fly EVERY PLANE *far* past what it would have done in real life, even when the other parameters are correct.

Every warbird operation manual I've read includes the phrases "prohibited manuvers: inverted loops and snap rolls" (and sometimes some others). While the only plane I've seen pull an inverted loop is the BI-1, I think we all know how often folks snap roll all over the place.

Regardless of how accurate the numbers are that we plug into these planes, we're still flying them beyond what they could really take.

That's what I realized when I was watching the 1C folks fly last night--they don't fly like that. They fly like REAL pilots (because many of them are). They push the plane, but nowhere near as far as you'll see online, because they're flying it as if it was a real aircraft with those structural limits. Maybe just out of subconcious habit, but they very definitely fly different.

Another thing that made me wonder even more if this is the root of some of our problems was comparing some of my online recorded tracks to gun camera footage.
One thing is defintiely clear--the average amount of deflection in most FB combat (far moreso online than single player) is about two or THREE TIMES as much as I ever saw in any of the footage I've collected and watched--over five hours worth, from all theaters, and both sides.

I think quite a bit of the 'uber-ness' some of the planes seem to have is due to one critical thing: we're flying them past what they could have taken. Some of them very well may have been able to pull 8 or 9-g snap turns. Once. Maybe twice. Some of them might have been able to pull out hard from a 6-700 kph dive inside of 400 m. Most of the time.

What sealed the theory for me, though, was watching a remote control glider one of my uncle's buddies built when we were up slope-soaring about a month ago. The thing was extremely light, and the main wingspar was machnied out of *lightweight aluminum*. Should have held up to anything, right?
Heh.
He pulled it out of a steep dive and the spar folded like a piece of paper. Plane went straight down like a rocket.

A lot of the planes we're flying were something in the order of multiple TONS. They didn't have that much of a buffer zone between their maximum capabilities and the point where they'd come apart. But right now, those limits don't exist, and the planes can do things no aircraft could ever do, even when the other performance figures are exactly correct.


So 1C, Oleg, please consider this. Even if it's very simple, even if it's only for the flyable planes, even if you have to make educated guesses about some of the figures--please seriously consider adding in airframe stress damage. The game desperately needs it. The original AirWarrior had it, CFS3 has it, I think EAW had it, and other, far older sims have included it because of how critical it is.

Our incredible game needs it too.

Stenciled on the side of my Dora:

"Lasst das H√¬∂llentor √¬∂ffen, es friert hier oben!"
("Leave the gates to Hell open, it's FREEZING up here!")

XyZspineZyX
09-27-2003, 03:04 AM
Like there isn't enough complaints with damage modeling already.

XyZspineZyX
09-27-2003, 08:42 AM
I think the author of this post hit the nail right on the head.

Imagine yourself as a real pilot in a real WWII dogfight. You take some hits from machine gun fire on your wing. You get SCARED and try to limp back home because you KNOW if you have to pull a hard maneuver, you could break your wing off.

Now come back to reality. You are in your pixel fighter and you take some hits on your wing. You climb, dive, whatever appropriate to re-engage your opponent because you have no fear of your wing collapsing in your next turn. Sure, your top speed might be affected, your plane may be harder to control, but you can still get right back into the fight.

Now add that to a historical arena. You make a nice deflection shot on a plane. That should make the guy (Or gal, to be politically correct /i/smilies/16x16_smiley-happy.gif ) go home in fear of losing his plane and or life. Instead, he just keeps snapping around like nothing ever happened. In fact, the only way to take your opponent out of the picture most of the time is to make his plane explode. Not very realistic in an historical sense.

I think that is the singular most critical reason it's harder to fight with high wing loaded (B&Z) type aircraft (109, 190, P47, P51 - when it comes out) in this game than low wing loading planes. You cant (Most of the time) stay on an aircraft long enough to cause that great of an effect on your enemy, when in reality, a few good hits should send them running for home.

Damage models in this game are great (With exception of a few planes - as already noted and being worked on). Airframe stress limits, especially after being hit, simply stink.

On the other hand, the problem with modeling them into the game is determining what is critical, what is not. Which planes should take more "Unaffected" damage versus which should be more fragile. That leaves a great deal of subjectivity open for the developers, and to some extent, I can understand them just leaving the issue alone. But Oleg and Co. we all know your credentials, and I think you of all people should be able to make a "Good guess" at what and how to model this into the game. I mean some of this is probably "No brainer" stuff like a P-47 should take more damage than a cloth covered bi-plane. Even if the model were rough around the edges and the same for each plane, (With exceptoion of the obvious) it would be better than not having it at all.

XyZspineZyX
09-27-2003, 12:57 PM
I think this is the only major shortcoming of the sim. Sure it has tuning errors and bugs and such, but these can be worked out. Unfortunately I do not see that there is much chance of this sort of thing to be patched in. Hopefully the next sim will have it.

If possible with FB then I think a simple explode/fall apart threshold should be created similar to the maximum dive speeds but using G loads instead. I would also like to see a colour coded G bar that would give a rough indication of your current G loading (say -1 - 1, -2 - 3, -3 - 6, -4 - 9, so that you have some clue that you are near the edge of the G limits as you fly).

I saw (used to have on HD but forgot to save before a reformat /i/smilies/16x16_smiley-sad.gif ) guncam footage from a FW190 that showed a P38 making a pretty hard turn that looked similar to what I have seen online (though the filmspeed makes it hard to judge how fast things are), but there is alot online as well as by the AI that you will never see a real plane do because no pilot would ever subject himself to that. Having your screen turn red or black is pretty obnoxious, but having your own body go through those forces over and over is far more than just obnoxious. Not to mention the lateral forces. I think tighter modelling of pilots' physical limits would help as much or more than planes' stress limits.

XyZspineZyX
09-27-2003, 01:08 PM
It could be very simple.

There's a G calculation for the blackouts. Let's use this G calculation also for the airframe: too much G, bingo no more wing. Damaged wings, breaking coming faster /i/smilies/16x16_smiley-happy.gif

Cheers,

XyZspineZyX
09-27-2003, 02:50 PM
I think PlaneEater has an excellent point.
I really don't care how planes are modelled FM-wise. I tend to stay out of the FM discussions, and just accept and fly whatever 1C gives me.
However, I have long wished the IL-2 (and now FB) would model structural limits of airframes. It's such an important part of air combat, that I can't understand why it hasn't been modeled.
I say ignore all the FM-whiners for a while, and concentrate on adding this feautre, even if in limited form, to the sim.

XyZspineZyX
09-27-2003, 03:27 PM
I couldnt agree more and have posted about this before since il2 sturmovik, but it has fallen of deaf ears.

I understand that they can't redo all the models to graphically add it in but at least they can add in a overstressed airframe sound that would cause reduced performance.

Alot of a/c can perform some totally unrealistic manuevers no a/c of the time would have survived because of airframes being overstressed, You can't even get into an unrecoverable dive from stick pressure.

The past max dive speeds are silly one alieron tab and one elevator tab rip off but you still have full use of them, pretty arcadish if you ask me.

You can loose wings and explode into a million pieces but you hardly ever see anyone do that just loose the one alieron and elevator and they fly just as good as having both.

Hopefully oleg and team will get rid of the arcadish movements, add some real simulated stick pressures in a few of the planes that dont seem to have any modeled in them, add energy bleed in certain planes rolls and slow down the roll left and instant snap roll right manuever everyone is exploiting, add some stick pressure, red out and black out to excessive rolling a/c. To me its the thing that annoys me most about this game.


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XyZspineZyX
09-27-2003, 07:13 PM
I disagree. Well, I agree, but not about everything. Yes, the planes should have damage from overstress, but "prohibited manuvers" don't mean the plane can't perform them, only that it hasn't been approved that the plane can recover, or that a possible overstress can occur if the manuver is done incorrectly. There are a host of other reasons that a manuever is prohibited, but it isn't because the plane will vaporize if the manuver is attempted.

Small single engine planes list snap rolls as prohibited, but there aren't many that can't do some form of it, and stay together perfectly well. Many planes list spins as prohibited, but people do spins in them all the time.

XyZspineZyX
09-27-2003, 10:22 PM
'Prohibited Manuvers' didn't mean 'this plane literally can't do those'--it meant 'you try those, you're taking your life into your own hands and the odds are stacked against you bigtime'.

I honestly think this is the missing aspect that's leading to any unbalanced planes. MANY of the 'uber' planes people whine about were made of lighter materials, such as wood, which granted them their superior climb and turn performance, but at the cost of them being far more susceptible to catastrophic failure during extreme maneuvers. Even the object viewer text mentions wing failures on the La-5s, and I'm sure those weren't the only ones.

Stenciled on the side of my Dora:

"Lasst das H√¬∂llentor √¬∂ffen, es friert hier oben!"
("Leave the gates to Hell open, it's FREEZING up here!")

XyZspineZyX
09-27-2003, 11:09 PM
This is a very good post. I agree 100% on haveing stress limits affect aircraft. This deserves a "bump".



Message Edited on 09/27/0310:11PM by ChainsawPolka

XyZspineZyX
09-27-2003, 11:15 PM
~S!

Bump, Planeater.

Most WWII fighters where build around untimate load factors of 7.5 to 9.0 positve G and maybe 4.5 negative.

Over G has not been simulated since day one in IL2, just flutter.



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XyZspineZyX
09-28-2003, 07:21 AM
bump consider it 1c for this sim, and use it as a test for your next wwii sim


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Good dogfighters bring ammo home, Great ones don't. (c) Leadspitter

XyZspineZyX
09-28-2003, 09:08 AM
LeadSpitter_ wrote:
- bump consider it 1c for this sim, and use it as a
- test for your next wwii sim
-

Great idea Lead.. Try it out in this sim, and use what you learned to perfect it in the next sim! Heck, you could even make it a toggle-able option so if it comes out totally buggered, (Which I seriously doubt) people hosting could simply turn it off.

WHy not give her a try Oleg?

XyZspineZyX
09-28-2003, 06:03 PM
I defintely agree with airframe stress limits. Modern day fighters (at least FA-18/A/Bs) had to have overstress inspections if they pulled more than 8 positive Gs when I was in the service, and some of them were damaged, having pulled 8.5 Gs, and had to be sent off to depot for airframe repair. The addition of airframe stress limits may well eliminate "FM whining".

XyZspineZyX
09-28-2003, 11:43 PM
I hav'nt a clue how accurate Rowans MiG Alley was but it did have a rather unforgiving stress model.

It was something you had to think about all the time , pull to many Gs and you lost your wings.

In FB you can take a MiG and dive it but you really need to watch the speed or you lose yor control surfaces, but if you dive in a 109 or P47 you can pull out at tremendous speeds.

adlabs6
09-29-2003, 12:47 AM
I too have wanted frame stress since IL2.

I wonder how the online play experience would chage with the addition of overstressing? I've heard 109 pilots using BnZ sometimes talking about how tough it is to aim in a 700 to 800 kmh dive. I believe I once read that a dive on target should be in the 400kmh range.

If you were in a real 109, and dove on a target at 700kmh, and then sucked the stick back as far as possible to zoom back up 1000 or meters OR MORE above the bottom of your dive, would the plane survive? Could you do this over and over? Put some machine gun rounds through the wing and still do it? I have no idea. But it's a common way to fight online, and a pilot who does it well is darn tough to kill (for me anyway).

Given the issues going on with the sound, etc. in FB there's likely no chance of this being added into the FB code. But there's no reason the next simulation shouldn't simulate G-stress.

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XyZspineZyX
09-29-2003, 02:28 AM
Would be good to see airframestress implemented, so I'll give it a BUMP

rgds

XyZspineZyX
09-29-2003, 02:38 AM
What you guys think about this:

"Are the stories true, that the 109 had weak wings and would lose them easily?

He has never heard of a 109 losing its' wings from his experience or others. The wings could withstand 12G's and since most pilots could only handle at most 9G's there was never a problem. He was never worried about losing a wing in any form of combat."

Franz Stigler Conversation
http://www.bf109.com

Message Edited on 09/29/0301:40AM by BVG_Erick

XyZspineZyX
09-29-2003, 05:40 AM
BVG_Erick wrote:
- What you guys think about this:
-
- "Are the stories true, that the 109 had weak wings
- and would lose them easily?
-
- He has never heard of a 109 losing its' wings from
- his experience or others. The wings could withstand
- 12G's and since most pilots could only handle at
- most 9G's there was never a problem. He was never
- worried about losing a wing in any form of combat."
-
- Franz Stigler Conversation
- http://www.bf109.com


That probably was very true, Erick... right up until the part where I put a .50 cal or 20mm through one of the wing ribs, or--god help you--a mainspar, and that plane instantly has a max stress limit of about 3 Gs. If it's in a good mood.



Stenciled on the side of my Dora:

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("Leave the gates to Hell open, it's FREEZING up here!")

XyZspineZyX
09-29-2003, 06:04 AM
bump

Maintaining the database of airframe statics for all the planes would be royal pain though and would lead to endless (harmless) strings debating spitfire main spar advantages etc etc...

T_O_A_D
09-29-2003, 06:58 AM
I agree and have been on this bandwagon many times since the beggining of IL2, but hey if someone has screwed the wheels back on this old thing count me in I'll ride till the wheels fall off again.

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XyZspineZyX
09-29-2003, 07:11 AM
I think it's a good idea. Considering we already have blackouts, and obviously the flight model knows the difference between positive, and negative G's.

Of course I doubt other than maybe some extra planes we'll see any more patches. I don't see that it would take much I mean it could be correlated with the G forces. The damage model is already there for the wings coming off.

If not that at least the blackout model should be fixed. I mean why can I still see? Not only can I still see although my vision is dimmed I can continue to fly the aircraft. I mean blacking out especially at low altitude is 9 times out of 10 fatal. Also it should last longer when you hit blackout. The 4 or 5 seconds it takes for the screen to clear up is nothing. Especially considering you can still see, and fly the aircraft.

Just make the screen go pitch black, double the blackout time, and disable the controls when it happens. Lack of proper physical conditioning, and poor or no G-suits meant most WWII pilots blacked out at 6 G's. A few could pull more, and a other less. So if you make the blackout model correct it really doesn't matter if the G stress is modelled.

Because when someone tries a bat turn or pulls out of a dive at 700. They're gonna blackout, and most likely crash.

Every take-off is optional, but every landing is mandatory!

XyZspineZyX
09-29-2003, 10:35 AM
could we just modle the actual stress limit before damage them use the same %loss of structual strength per %of damage in each air craft every bodys equal then no comlpantes if some one complains (and some one will)this plane coud take 5 50's in the wing and be fine wa wa wa so im really come on its close all wings are created smillary so the effects of damage would be simaler to right or mabey one set of calculations for wooden winged ac aond one for meatle? just my 2 cents would be nice to have in any form even if its limited

XyZspineZyX
09-29-2003, 10:48 AM
This was known to 1C for a long time. Even before FB was announced as coming (summer 2002). Somehow I really do think that if it could be done without a major impact on the rest of the sim they would at least have tried it out. but that is not to say that it would have passed the tests before making it into a patch.

Try thinking also why it might not be. It would seem a very good thing to have for sure to me but I do not see everything as it would be and just maybe 1C has from trying already. We can all agree that it is a good idea and seems like it should not be so hard but some people go from there to the 'get angry' stage and then comes the insults and conspiracies. Those insults and conspiracies may be why it is not there now. As was noted there would be a roaring, raging, endless series of debates about which planes were how--- my planes should this while the other(s) should that--- and always talk of bias but none of that may be the real reason it is not in.

Please give the team a break when it comes to anger and the 'I am ignored' syndrome.


Neal

XyZspineZyX
09-29-2003, 11:33 AM
One of the 100+ german aces lost his life exactly that way.


BVG_Erick wrote:
- What you guys think about this:
-
- "Are the stories true, that the 109 had weak wings
- and would lose them easily?
-
- He has never heard of a 109 losing its' wings from
- his experience or others. The wings could withstand
- 12G's and since most pilots could only handle at
- most 9G's there was never a problem. He was never
- worried about losing a wing in any form of combat."
-
- Franz Stigler Conversation
- http://www.bf109.com -
-
- Message Edited on 09/29/03 01:40AM by BVG_Erick



312_Lazy
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XyZspineZyX
09-29-2003, 11:35 AM
A plane made of wood is not lighter that the one made from metal. It's exactly opposite.


PlaneEater wrote:
- I honestly think this is the missing aspect that's
- leading to any unbalanced planes. MANY of the
- 'uber' planes people whine about were made of
- lighter materials, such as wood, which granted them
- their superior climb and turn performance, but at
- the cost of them being far more susceptible to
- catastrophic failure during extreme maneuvers.

312_Lazy
312. (Czechoslovak) Sq. RAF
http://312.jinak.cz

XyZspineZyX
09-29-2003, 01:08 PM
"In FB you can take a MiG and dive it but you really need to watch the speed or you lose yor control surfaces, but if you dive in a 109 or P47 you can pull out at tremendous speeds."

That's a bit different problem. In a normal high speed dive, the planes are all still just in 1G limit. The Migs ripping their flight surfaces out at those speeds are but a testament to their less resistance towards extreme speeds.

The problem of pulling too many Gs, is a different problem entirely.

However, in this case, I think even a simple solution as suggested by many, would do - just model in a 10 G limit to wing or rear fuselage. Maybe a little less for planes that were known to have especially weak surfaces.

Go over that limit, and the wing breaks off... I don't think anybody's gonna complain about that. Pulling 10 Gs, is an enormous thing.

...

The differences in planes might be interesting, if structural G loading limits are modelled.. for instance, if the Bf109s are flying at speeds enough to create 10 Gs, the pilot wouldn't have enough elevator control to pull that much Gs anyway..

The Fw190s were cleared to about 8Gs, if I remember correctly. I think they'd be great in high speed turns, but still not enough to pull more than 9Gs.

The P-51s, on the other hand, have numerous reported problems concerning high-speed pullouts. Hub Zemke's instance was probably the most famous. I think this would mean the P-51s had either 1) a bit lower tolerance in the wing structure, or, 2) it had an elevator authority which would allow the pilot to pull upto the point where the wings would fall off.

The Hawker Typhoon's also an interesting case. Pilots of this plane, were instructed not to use trims to recover from a high-speed dive. Structural problems in the rear fuselage would cause a tremendous nose-up attitude once the plane escaped compression speeds, causing a momentary high G status which ripped the rear fuselage off.

...

It really would be interesting if this issue was addressed.



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XyZspineZyX
09-30-2003, 12:22 AM
10 G's?????

Modern pilots in special suits and couches can handle 9 G's for seconds.

You look at turn performance charts for WWII era and see all the turns max out at 6 G's -- because that's where the pilot failed. Without special suits, couches and training there is no pilot going to take more than seconds, momentary, at 6 G's.

10 G's? The pilot will be unconscious for a long time before he gets to any 10 G's, if he isn't dead. Yeah the planes should come apart but that shouldn't be a sim problem.

The problem is when the pilots don't go unconscious long enough after hard G's if there's a problem at all. Where do we hit the greyout in G's? 5? 5.5? 6? Is time at G-force part of it? How do you tell?

With damage to the structure there should be lower G limits in a very realistic sim but it may not be possible with all the other features we have in IL2/FB. More likely the damage is taken and the wing fails then, consider some of the complaints about 1 shot wing failures.


Neal

XyZspineZyX
09-30-2003, 01:51 AM
WWMaxGunz wrote:
- 10 G's?????
-
- Modern pilots in special suits and couches can
- handle 9 G's for seconds.

Not that those toys are needed of course. /i/smilies/16x16_smiley-wink.gif

XyZspineZyX
09-30-2003, 02:08 AM
Is there not any damage modeling on stress at all? I thought there was some but not well done, or maybe not completed. I was playing with a FW the other night and dove on a guy on the deck and shot him up. As I went by, I was going very fast and was going to extend instead of pulling up. He managed to get the nose up enough to hit me in the right wing root with the LA guns. Looked and sounded like one good hit. I pulled the nose up and rolled right a little. As I looked back around the seat, I saw he had managed to level back off and was smoking very badly and not manuevering, so I decided to hit him again and saw a teammate heading down. I wanted the kill so I pulled the turn very hard up on one wing at the edge of black out when suddenly that damaged wing broke off at the root and I spun like a top into the ground. I figured it was from the previous damage. I know on the jug if it has been shot up that sometimes a small burst of 30 cals will make it break in half. I thought the damage was cumulative.
Is this a FW bug?

WYS
AB_Onedoc

XyZspineZyX
09-30-2003, 08:00 AM
Sounds like you caught a stray bullet. There isn't ANY stress model in FB at the moment, so that's all that it could have been.



Stenciled on the side of my Dora:

"Lasst das H√¬∂llentor √¬∂ffen, es friert hier oben!"
("Leave the gates to Hell open, it's FREEZING up here!")

XyZspineZyX
09-30-2003, 10:36 AM
How can you be entirely 100% sure?

I remember last time this topic was big (wasn't it before IL2 v1.2 came out?) that I read posts of the same thing as OneDoc had happened where some time after hits a wing came off. In those discussions there were some pretty wild claims as to G's pulled in terms, usually qualified by the words "must have been". I have yet to find anyone able to guage radius and speed to find out better than guesswork.


Neal

XyZspineZyX
09-30-2003, 10:45 AM
Yeah, but Max, dont you think a guy with Oleg's qualifications would be able to make a much better "Guess" than most? In fact, isnt most of the damage model guesswork? Taking a round in the engine will do damage, but all the time? Angle of trajectory, exact componant hits, etc are pretty much subjective. I just think stress limits would be a welcomed addition to the game.

XyZspineZyX
09-30-2003, 08:56 PM
No airframe stress limits modelled? Now, try diving any Yak fighter for some higher speeds (700km/h and up /i/smilies/16x16_smiley-tongue.gif )

Also, in high-speed manouvres, you sometimes get a G-loc, your controls won't respond anymore because you faded out temporarily.

Anyways, how should this be modelled? we allready have the black-out effect wich should warn us for high-G's but, most of us ignore this signal. especially on servers with externals on. External view should be blacked-out also.

1 Judge not, that ye be not judged.
2 For with what judgment ye judge, ye
shall be judged: and with what
measure ye mete, it shall be
measured to you again.

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XyZspineZyX
09-30-2003, 09:25 PM
Platypus, wing failures at high speed aren't exactly airframe stress. That's more a representation of terminal dive speed.

What we're talking about is excessive G forces or pulling Gs on damaged structure causing structural failure.

- Also, in high-speed manouvres, you sometimes get a
- G-loc, your controls won't respond anymore because
- you faded out temporarily.

That's two other things. Either blackout (not airframe stress) or compressibility (not airframe stress). I've got a great track of a BI-1 pulling inverted loops if you want to see what compressibility can do at high speed...

Stenciled on the side of my Dora:

"Lasst das H√¬∂llentor √¬∂ffen, es friert hier oben!"
("Leave the gates to Hell open, it's FREEZING up here!")

XyZspineZyX
09-30-2003, 11:23 PM
Right on!

Have you seen the absurd maneuvers the AI piloted He-162s perform? Those violent corkscrews will be a perfect match for Lukas' refreaction-free fantasy cockpit.

<font size="-2">'Perfect' is enemy of 'good enough' --Admiral Gorshkov
It's a trap! --Admiral Ackbar</font>

XyZspineZyX
10-01-2003, 01:15 AM
I would Guess that Oleg & Team know G loads pretty precisely.

And as far as engine damage, remember the views we had showing how many engine parts are modelled? But then the great thing about details is getting them right. A complex machine or virtual machine can be complex garbage if any neccessary part is made or assembled wrongly. It's also much harder to test a virtual machine by far than a real one. Simplicity has its advantages.

We keep seeing anecdotes about engines being hit and still flying or engines being vulnerable. I have yet to see actual statistics on engine damages to downed planes of any model. What percent were engine-killed or killed after the engine was so damaged as to lose performance? How much damage did that take? Those sorts of things. I wonder if 1C has such data or is extrapolating from design drawings? One person posting here shows I think it was Kit Carson with 12 FW190's killed with shots to the front of the engine resulting in immediate fires and yet another poster says there's an armored ring over the oil lines so that's not possible. I wonder how covered those lines were since the object was to get airflow over them, but someone will doubtless conject that the lines and engine parts got flow and were armored to near invincibility at the same time. The pilot who got the kills wrote that his shots must have ricocheted once inside the cowl and the oil lines being thin and crowded there got clipped, sprayed oil over the hot cylinders and flashed into fire immediately. They'd have drained the oil out pretty quick too. If that was Carson he also had opportunity to examine the FW engines and an engineering degree to be able to understand what he was seeing.

Does that mean that the DM is right? No. Does it mean it's wrong? No. Does it mean shut up? No. It only means that the cases are not presented well or deep enough to be conclusive, at least from what I see.


Neal

XyZspineZyX
10-01-2003, 01:17 PM
Max,

I am getting the feeling that you really dont want to see stress limits placed on aircraft in this game. Am I interpreting your posts incorrectly? If I am correct, I really dont understand why you feel that way. Yes I agree, the KISS (Keep it simple stupid) method is almost always better, but stress failure was and is still always a concern of a fighter pilot. It's just simply not modeled in this game, and "I" think it would be a really cool addition.

Sure some of the work would be "Best guess" but honestly, a lot of this game is. Nothing mechanical performs exactly as intended. Build two identical motors with identical tolerances and dyno test them both. You will quickly discover that, although you can come close, but no two pieces of equipment will be exactly the same. Racing would be boring and uneventful if they were.

Adding in stress limits would just add a little more fear into the game, and thus add to the overall immursion, if you ask me. Pilots always have to worry about the limits of their aircraft (Unless you are in fly by wire jets, because the computer worries about it for you). It's just simply not a factor in this game currently.

Oh, if I am incorrect about your opinion on stress limits and their addition into the game, I'm sorry. Perhaps you are just worried about subjectivity vs.objectivity that could result in poorly modeled limits. For this, I share your concern, and that's why I recommend a toggle-able control over their use. If they are found to be crap, turn em off... /i/smilies/16x16_smiley-happy.gif

But if done well, just think about how much more enjoyable this sim could get!

XyZspineZyX
10-01-2003, 08:00 PM
Stress limits aren't just an immersion factor--they're one of the MAIN aspects of combat flight.

Right now, because we don't have them, many planes are doing things they could never do in real life, even when the rest of their flight model is very close to dead on.

Not having airframe stress is also the reason we had trim-slider abuse in the original IL-2. If it had been implemented, trying to use trim in that manner would have been a guranteed method for snapping your wings off, REGARDLESS of which plane you were flying.

So implementing this also solves some problems--it would let us have real, responsive trim again, without trim slider abuse.

Stenciled on the side of my Dora:

"Lasst das H√¬∂llentor √¬∂ffen, es friert hier oben!"
("Leave the gates to Hell open, it's FREEZING up here!")

XyZspineZyX
10-01-2003, 09:20 PM
I'm not sure that lowered stress limits due to damage isn't in the sim now! It may not be modelled how we think it should but that may be the limit without severe impact elsewhere in the sim. I'd love to see it done to where ... well the problem is that I don't know exactly what it should be like, only have an idea that with light damage to the main spar(s) a wing should fold up and break off at lower G's than before.

A new, unstressed WWII fighter will take more than the pilot can possibly take and survive while a combat stressed plane might not but since all planes in the sim start in mint condition it's only damage that can make this happen. That's a condition of the sim. I read occasionally of people who have taken wing damage and later had the wings break off. How am I to interpret that? It must be another shot to the wing because stress isn't modelled? I guess that a track is needed in the absense of direct information from Oleg, which we always get some who call him a liar anyway sometimes in as many words.

Maybe if enough people ask without making assertions or insults then we might get an answer on this and other details. A lot of people here are convinced of things that I can't see are more than hunches and bad guesses. Again, damage stress may be in there but not modelled to the perfection expected.

Perhaps the code mechanism is in there and only needs to be tuned. Maybe someone on the team sees assertions that there is no stress limits modelled and they know the code is there but maybe they don't think they got it all wrong the first time. Have you ever done that? Made something you thought was right and someone else didn't? I know I have! It is very possible that we have asked the wrong question, pointed out the wrong place as the problem. The workers look and see no problem so assume the complaint is in error. This happens a lot in the software industry... much more than I would care to have seen.

As you can see, my position is not simple due to the fact that I don't believe we have enough information to define the problem enough to make assertions about the nonexistence of stress limits in the code.


Neal

XyZspineZyX
10-02-2003, 12:20 PM
I see your point Max. I guess the reason I dont believe it exists is totally based upon the fact that I have never experienced a failure based on damage/high G's. I have had a reduction in performance due to damage, but I always assumed it was because of lift, drag, etc. I also agree with an earlier post talking about adding stress limits to help neutralize the "Trim cheaters". There have been many debates here in the forum about trim, but the simple fact is that it can still be exploited in this game. - But that's another arguement entirely, I surely dont want this thread to turn into a trim debate...

I just hate to even use the word "Trim" because it's like saying "Candyman, Candyman, Candyman" but instead of an evil killer popping up, we get RBJ.. LOL


WWMaxGunz wrote:

- Have
- you ever done that? Made something you thought was
- right and someone else didn't?

Naw, not me man. I never make a mistake. Nope, not once in my whole life. I almost made one once, but I corrected myself. LOL. Hey, check out my name.. It's German for "ERROR" LOL

XyZspineZyX
10-02-2003, 12:33 PM
airframe stress and flutter effect was something implemented in SDOE several years ago.
I remember pulling out of a dive on a typhoon with bombs on the raks and the wings bending and breaking!!! FB planes look "stiff" sometimes...

SJ

http://www.il2sturmovik.it

Visita il portale italiano di IL-2 Sturmovik!!!

XyZspineZyX
10-02-2003, 01:18 PM
Max, a report from the pacific.

....

A. H. Peterson, "Aircraft Vulnerability in World War II", Rand Corporation, 1950

Document number # RM-402(Page 53)

Aircraft lost to hit ratio for hits on components from Japanese Aircraft Fire
- Sept '44 ~ August '45

(specimens are F4U, F6F, SB2C, TBM.. all radial-engined)


Hit location........../.hit./.lost./.Loss %
--------------------------------------------------
Propellor................9.....0......0
Powerplant..............37....23.....62.2
Structure..............215....23.....10.7
Pilot/flight controls...97....74.....76.3
Surface Controls........27.....0......0
Oil System..............27....23.....85.3
Fuel System.............30....24.....80.0
Hydraulic System........35....21.....60.0
Electrical System........6.....0......0
Other...................18.....5.....27.8
--------------------------------------------------
Total..................501...193.....38.5



The causes of losses in arranged in weighted order:

Oil System (rate of loss 85.3% )
Fuel System (80%)
Pilot/flight controls (76.3%)
Powerplant (62%)
Other (27.8%)
Structure (10.7%)
Propellor, Surface controls, Electric system (0%)





-----------
Due to pressure from the moderators, the sig returns to..

"It's the machine, not the man." - Materialist, and proud of it!

XyZspineZyX
10-02-2003, 01:27 PM
Aircraft on FB DO have stress limits. All planes do break up in dives or become harder to pull out in dives, the prime example being the BI-b.
The stress limits may not be perfectly modelled, but there are more important things that need fixing.

XyZspineZyX
10-02-2003, 05:12 PM
Danschnel wrote:
- Aircraft on FB DO have stress limits. All planes do
- break up in dives or become harder to pull out in
- dives, the prime example being the BI-b.
- The stress limits may not be perfectly modelled, but
- there are more important things that need fixing.
-
-

I disagree with you. I think that is more of a representation of terminal dive speeds as stated earlier, nothing more. What we are talking about is more along the lines of getting hit and not being able to perform bat maneuvers for fear of losing a wing or tail. Just because you lose parts during a straight dive has nothing to do with the amount of G's an airframe can take, especially after taking some damage in critical areas. If stress is modeled, what you are describing is not it. You dont black out (Pull excessive G's) in a prolonged high speed dive. (Well, you can, but long after the plane dissintigrates around you)

As far as things needing fixed that are more important, I also disagree. As the chart posted earlier shows, 10% of those aircraft listed that were lost, were lost to structural failure. That's 1 of 10. That's a huge number if you really think about it. To me, that gives me an even greater appreciation for the need for structural limiting in this game.

XyZspineZyX
10-02-2003, 09:26 PM
kweassa wrote:
-
- Max, a report from the pacific.

And this is good material to have. How to interpret it?

-
- A. H. Peterson, "Aircraft Vulnerability in World
- War II", Rand Corporation, 1950
-
- Document number # RM-402(Page 53)
-
- Aircraft lost to hit ratio for hits on components
- from Japanese Aircraft Fire
-- Sept '44 ~ August '45
-
- (specimens are F4U, F6F, SB2C, TBM.. all
- radial-engined)
-
-
- Hit location........../.hit./.lost./.Loss %
---------------------------------------------------
- Propellor................9.....0......0
- Powerplant..............37....23.....62.2
- Structure..............215....23.....10.7
- Pilot/flight controls...97....74.....76.3
- Surface Controls........27.....0......0
- Oil System..............27....23.....85.3
- Fuel System.............30....24.....80.0
- Hydraulic System........35....21.....60.0
- Electrical System........6.....0......0
- Other...................18.....5.....27.8
---------------------------------------------------
- Total..................501...193.....38.5

Sooooo... out of 215 planes that took hits (enough to damage?) to structure (mainly?) there were 23 of those lost?

That's my best guess, Planes Hit / Planes Lost / Loss%.

From how specific the areas shown are I'm only guessing that 1 hit is all it took and the Loss% tells *about* what % of the time the one hit would bring a plane down *on average* since plane models aren't mentioned.

I would also guess that Structure isn't fuselage skin but actual major rigid supportive members.

- The causes of losses in arranged in weighted order:
-
- Oil System (rate of loss 85.3% )
- Fuel System (80%)
- Pilot/flight controls (76.3%)
- Powerplant (62%)
- Other (27.8%)
- Structure (10.7%)
- Propellor, Surface controls, Electric system (0%)

I was looking at weighting those %'s by the number of hits for each area and got some strange results... they all came out to being the same at 4.6%. If I weight Structure hits to Oil System hits and multiply by Structure Loss % the I get Oil System Loss% or near enough as counts for rounding. That's not something I'd expect from raw data but then perhaps it's the results of the aircraft designers working to not make Achilles Heels, again *on average*. More likely it's just something in the algebra I'm overlooking, I just had major dental work and I'm not in any mood to go chasing things down so maybe someone else can see the obvious?


Neal

XyZspineZyX
10-03-2003, 02:35 AM
Danschnel wrote:
- Aircraft on FB DO have stress limits. All planes do
- break up in dives or become harder to pull out in
- dives, the prime example being the BI-b.

actually they dont. Before breaking apart a plane should show flutter effect, which doesn't happen in FB

- The stress limits may not be perfectly modelled, but
- there are more important things that need fixing.

actually it is really important, airframe stress is something u always have to care about, if u pull a "stick to the belly" manouver when flying at high speed there's a serious risk to pass the structural limits of the machine u r flying, this resulting in yr wings ripping out and closing like a book...

SJ

http://www.il2sturmovik.it

Visita il portale italiano di IL-2 Sturmovik!!!

XyZspineZyX
10-04-2003, 01:12 AM
Bump.. Would be nice to hear from the Dev team on this issue.

XyZspineZyX
10-04-2003, 01:43 AM
I play off line and I have argued before that the unrealistic aerobatics performed by AI aircraft is a real distractor from feeling as though you are playing a simulation and not just a game.

I have read 100's of accounts of fighter combat in WW2 and most talking about diving away, climbing, pulling a hard break towards the bogey, etc. Except for the Japanese, I have not read of anyone who looped or did barrel rolls in combat. In one book I read recently, the pilot was told that a high speed barrel roll was a good way to evade someone on his 6. He tried it and was almost killed. He was a flying a Helldiver or SBD but he was an experienced pilot. His response was to go back to his base (training) and suggest to a friend that the high speed barrel roll was something he should practice.

The lack of structural limits and an AI that flys in unrealistic ways really reduces my enjoyment of FB.

Much of the modern ACM that you read about in Shaw was developed in the 50's and 60's. Much of it would be (IMHO) crazy in an environment with multiple threats. Engagements in Vietnam were generally between very small groups of aircraft.

It really bothers me when I am behind an bandit and he pulls 5 or 6 rolls without any reduction in speed.

So I think structural limits and modification of AI behavior are both needed. I have had many structural failures in other sims but maybe (maybe) 1 or 2 in FB.

My approach has been to use UQMG to build missions with early (around 1940 planes) which were slower and generally capable of turning in a smaller radius. After 42, I think speed and tactics (bounce and run) became the norm. Certainly the 15 minute dogfight between two hard turning aircraft was very infrequent.

However, FB is still the best sim around.

Michael

XyZspineZyX
10-04-2003, 07:26 PM
Perfectly states, GMichael...

Bump.

Stenciled on the side of my Dora:

"Lasst das H√¬∂llentor √¬∂ffen, es friert hier oben!"
("Leave the gates to Hell open, it's FREEZING up here!")

XyZspineZyX
10-05-2003, 04:31 AM
Please.. Dev team let us know you have read this.

bump

XyZspineZyX
10-07-2003, 12:57 AM
Baaaaaa ump

XyZspineZyX
10-07-2003, 04:09 AM
I would be remiss if I didn't add that IL-2 and FB make one use more realistic tactics than any other sim I have played (possible exception of Mig Alley which I haven't used that much).

Just a few small changes in AI would help. As would some sort of stress model (give CFS3 credit for great metal creeks even though I never had a structural failure).

A little tweaking of the flight models to make the 109 more competitive in 41-43, and the ability to tell your wingman to break right or left (up or down) so you can drag a bandit in front of you. This would turn a very good sim into a great sim.

A few weeks ago I gave FB a very low rating in one of the forum polls. However, since I have started using UberDemon's generator and sticking to the older planes I have had a lot more fun. My rating would go up to a 4.

But I am still disappointed in the I-16. In IL-2 it stalled according to the accounts that I have read. To the left (I hope I don't have my directions reveresed) it would stall and spin but you could recover relatively easily. To the right and if you didn't catch it in the first turn it went flat any you were going in. You had to use the rudder very carefully. It felt like you were flying a beast that was a handful but it could be made to take out the 109s.

Now I just fly I-16s and Hurricane and lay waste to all those before (1940 and 41 AI aircraft).

Too easy!