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View Full Version : Anyone notice break up speed/g-force related differences with 4.10?



Noxx0s
04-08-2011, 01:43 PM
I dunno, but to me, it seems that when I'm flying in my two favorite planes these days, the Tempest and 190 (any), I have to be WAY more cautious about turns at high speed and just diving in general.

One of the oddest things I've had happen is that I was flying along in a Tempy straight and level at 500kph (not in a dive in other words) and my wing just suddenly broke off (I had been looking at the map for a second but was still flying straight when I closed the map).

Anyone else noticing the FM being less forgiving about break speed and that sort of thing?

Also I sometimes hear "cracks" in the plane but can't see any visible damage (nothing's broken off the plane) and this'll often happen at speeds of only 400-550 kph and not in ridiculously tight turns either...

Anyone else noticing this kind of thing or am I just crazy?

Aviar
04-08-2011, 02:00 PM
I tend to agree with you that the new g-limits don't seem quite right. I have no 'proof'.....just a 'feeling'.

I actually disable that difficulty setting when hosting my coops.

Aviar

PhantomKira
04-08-2011, 04:40 PM
I lost a wing off a P-38 under almost identical circumstances to those you describe. Straight and level cruise flight, no enemy around. No idea why that happened. Only happened once, though. Since then, I've routinely pulled maximum rate (possible at that speed, that is) turns at 300 MPH that should have had the thing coming apart at the seams, and it went merrily on its way. Hard to tell.

The "cracks" you're hearing are, according to the readme for 4.10, indications of overstress of the airframe, and resultant lower tolerances for the rest of the flight. They don't mean it'll come apart right now, but if you continue to push it hard, it'll eventually break. Example: 8G load Max - "crack" sound - Max G load now reduced to 6G. As I understood it, there is no visual indication.

Romanator21
04-08-2011, 06:01 PM
I haven't encountered any sudden problems, and I don't think I've broken anything at all (Except intentionally).

Could it be an effect of random failures/reliability? I was under the impression that this only affected the engine performance.

What surprised me though was that negative G causes the airframe to break at a lighter load than at positive G. One would think that it doesn't matter which way you push a cantilever spar, but maybe I'm wrong.

AndyJWest
04-08-2011, 06:55 PM
One would think that it doesn't matter which way you push a cantilever spar, but maybe I'm wrong.
If the spar was symmetrical, obviously, it wouldn't. Given that the need to withstand high positive G is likely to be more important then hign negative G, it seems likely that most aircraft wings are designed to different + and - G loadings. A classic example of this is probably the de Havilland DH.103 Hornet:"Construction was of mixed balsa/plywood similar to the Mosquito, but the Hornet differed in incorporating stressed Alclad lower-wing skins bonded to the wooden upper wing structure using the then-new adhesive Redux." (http://en.wikipedia.org/wiki/DH_Hornet) Presumably Alclad is better under tension, but wooden spars and balsa/ply skins resist compressive loads better without buckling.

M_Gunz
04-09-2011, 01:04 AM
The 'new G limits' also come with stress damage. You pull a hard one and maybe the wing doesn't come off then but it's now weaker and will come off at less stress. Keep doing the same and the limit gets even lower.

Romanator21
04-09-2011, 02:39 AM
Actually, I really enjoy the new feature. I've counted at least 5 times in which players online dove on me and simply lost a wing. Me-163, Ki-84, a couple Fw-190s. It's great. (A couple were an indirect result of intentional planning on my part - they weren't careful and payed for it. To bad I don't get a kill credit for those http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif )

@ Andy - thanks for clarification. It's easy to forget that the strength is not in spar alone, but in all the components as a whole.

Noxx0s
04-09-2011, 12:31 PM
Originally posted by Romanator21:
I haven't encountered any sudden problems, and I don't think I've broken anything at all (Except intentionally).

Could it be an effect of random failures/reliability? I was under the impression that this only affected the engine performance.

What surprised me though was that negative G causes the airframe to break at a lighter load than at positive G. One would think that it doesn't matter which way you push a cantilever spar, but maybe I'm wrong.

IS there some kind of "random failure" feature in IL-2? I wasn't aware of that... interesting.

Noxx0s
04-09-2011, 12:33 PM
Originally posted by PhantomKira:
I lost a wing off a P-38 under almost identical circumstances to those you describe. Straight and level cruise flight, no enemy around. No idea why that happened. Only happened once, though. Since then, I've routinely pulled maximum rate (possible at that speed, that is) turns at 300 MPH that should have had the thing coming apart at the seams, and it went merrily on its way. Hard to tell.

The "cracks" you're hearing are, according to the readme for 4.10, indications of overstress of the airframe, and resultant lower tolerances for the rest of the flight. They don't mean it'll come apart right now, but if you continue to push it hard, it'll eventually break. Example: 8G load Max - "crack" sound - Max G load now reduced to 6G. As I understood it, there is no visual indication.

Can this reduced tolerance happen and you not get a crack? (i.e. no warning)

Romanator21
04-09-2011, 01:14 PM
All engines have now small chance of failure at every moment of flight. Probability depends on
power generated by engine and its RPM (more power, bigger chance for an engine to fail). Not
every failure is catastrophic, some of them just reduce power, but if its not your lucky day
then you might end up with a problem. Purpose of this feature is to give a reason to be easy
on engine, not to follow historical failure rates of specific engines. This can be turned off in
difficulty settings.

The feature was added in 4.10, but I guess I'm wrong and it doesn't affect airframe strength.

M_Gunz
04-09-2011, 04:19 PM
From the 4.10 Guide PDF that you should be able to d/l with the patch... and never read....

now highlighted for easy finding answers


Structural G Limits
Before 4.10 patch all aircraft in IL2 have a single fixed Structural G limit of +13.5G. It only
really becomes an issue with aircraft with exceptionally light elevators such as the P-51. Pull
more than +13.5G and you loose your wings. The real life situation is a little more
complicated. Real aircraft are designed with an Ultimate load and In Service design load. Both
are for a defined configuration and weight.
In Service load is the typical G available to the pilot. As long as this the G is not exceeded then
no aircraft damage will occur. Exceed the In service G limit then damage of varying degrees
may occur like bent airframes etc. Exceed the Ultimate load then severe damage will occur
typically resulting in structural failure like wings coming off etc. Typically a safety factor of 1.5
is used. So fighter plane with a design In service G limit of say +8G will have an Ultimate load
of +12G. As external stores and or weight is increased above the design weight, both G limits
reduce accordingly. Reduce weight (by dropping bombs or burning fuel etc.) and your G limits
increase. Bomber and Transport aircraft have G limits much lower than fighters.
So if you abuse the limits you damage the aircraft. Once damaged then its structural integrity
is reduced so the ultimate load reduces as well. In other words keep bending the airframe and
you will eventually weaken it to the point that very little extra G is required to induce
structural failure. A bent airframe won’t perform as well either.
How does this work in game? You take your stock standard Fighter Mk 1 with default
armament +100% Fuel your limits are +8G/+12G. You add 2 x 500lbs bombs. Your limits now
reduce to 5G/8G. So prior to the target you need to be a little more careful with your plane.
Lets say pre target you pull + 6G, you have exceeded the “in service” limit, you will hear a
damage sound cue and suffer a slight aerodynamic penalty. In addition your G limits have now
reduced to say 5G/6G. Bust these again and further aerodynamic penalties and further
reductions will apply. You progress to the target and release your bombs. Since the weight is
reduced your limits will increase but since you already bent the airframe you won’t get back
your original limits. You might then get say +8G/+10G. As you can see if you keep abusing the
limits you will end with a very weakened airframe.
In the case of heavy bombers, G limits will prevent any real aerobatic maneuvers. You will still
be able to evade quite well but you wont be able to BFM with plane like the A-20 anymore.
Bombers will be just that: Bombers.
G Indications
When the speedbar is enabled an indication of proximity to the Service limit is provided. When
you get within 25% of the current Service limit a "G" will be displayed on the top of the
speedbar. As you get to within 10% of the current Service limit the "G" will begin to flash. The
process being reversed as you reduce the G. No G cueing is provided if Speed bar is
deselected.
If players use No Cockpit View than direct readout of G is provided. Number is white while G's
are above 0, when you get within 25% of the current Service limit number turns to red. Below
0G,number is black.

Noxx0s
04-09-2011, 05:49 PM
Thanks gunz... mystery solved http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif. Nice to know exactly what that "G" signifies too now.

I guess when I was flying straight at 500 kph I must have just pushed my a/c way too hard earlier and so even though I was flying level the speed just knocked a wing off. All I can figure. I was still pretty surprised though...

PhantomKira
04-09-2011, 11:12 PM
Originally posted by IcyScythe:
Can this reduced tolerance happen and you not get a crack? (i.e. no warning)

Not sure, I'd say no according to the readme...

And I'll add that I had done zero maneuvering prior to the failure. It was a simple "start-climb-cruise-break", which is why it was so odd.

M_Gunz
04-10-2011, 03:19 AM
Originally posted by IcyScythe:
Thanks gunz... mystery solved http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif. Nice to know exactly what that "G" signifies too now.

I guess when I was flying straight at 500 kph I must have just pushed my a/c way too hard earlier and so even though I was flying level the speed just knocked a wing off. All I can figure. I was still pretty surprised though...

It's quite likely that a very small wobble or spike of the stick commanded a very short elevator movement that made a tiny short G-force that you wouldn't notice except for the wing coming off. I recommend to everyone, put FILTER on at least the pitch axis (elevator) of their stick in the stick sensitivities settings. You -will- fly smoother.

PF_Coastie
04-10-2011, 07:53 AM
I had a similar experience in a P47 Late. I am wondering if this mod does not take Altitude into consideration.

I did a qmb against two Doras and started at 7km. During the fight I made a bad pass and zoomed back up to reset for another pass (all the while still at contrail height). When I was reaching my apex at about 9km, I had to wing over to keep my eye on the Dora and my wing popped off! I was doing less than 300kph at the time. This is absolutely crazy and should NEVER happen. Only maybe if I had damage to that wing by gunfire or something(visible holes in wing). I had complete control of the fight and never even took enemy fire.

M_Gunz
04-10-2011, 09:53 AM
Rolling the plane to bank, there are G forces on the wings. That first pullout must have been a lulu! But you are reading IAS in the pullout while G-force is by the TAS and here I kind of lose it... in a smooth pullout where the pilot doesn't grey out the whole thing should be 5 G's or less regardless of speed. But it takes a while to grey out and very short 'bumps' that your pilot (let alone you) wouldn't notice maybe do show up in the data and those are what the code is picking up. I wouldn't say that's wrong either. Fast onset of G's or impact is more than stable loading, it is kinetic and multiplies by speed squared.

Still got to wonder how they formulate loading, it can only be so complex and not be a noticeable framerate hit.

PF_Coastie
04-10-2011, 10:01 AM
I fly the jug a lot. It is my favorite plane. I have very soft settings on my MSFFB stick and rarely do hard pullouts. I recognize a "bad" AOA early and pull out early to not worry about blackouts. I rarely if ever black out in the jug because I know how to fly it. Spit is a different story, LOL, I spend more time in black out than not in that darn thing!

I understand about TAS/IAS, but it still does not compute to me. The plane should not have been stressed in this situation.

PhantomKira
04-11-2011, 01:40 AM
Originally posted by M_Gunz:
I recommend to everyone, put FILTER on at least the pitch axis (elevator) of their stick in the stick sensitivities settings. You -will- fly smoother.

You're telling me I've been fiddling with the blankity blank input percentages all these years when all I needed was the filter! http://forums.ubi.com/images/smilies/blink.gif "$&@#*$&^@!!" http://forums.ubi.com/images/smilies/compsmash.gif http://forums.ubi.com/images/smilies/51.gif

Geez, Gunz, my flying's improved already. Thanks! http://media.ubi.com/us/forum_images/gf-glomp.gif

Kettenhunde
04-11-2011, 06:21 AM
Rolling the plane to bank, there are G forces on the wings.

The load becomes asymmetrical. An airframe's load factor limits are designed bearing a load in one axis only. Adding load on additional axes greatly reduces the design axis load factor.

That is why pilot skill is so important in keeping the aircraft in co-ordinated flight during hard maneuvering. If a pilot cannot maintain co-ordinated flight, he is asymmetrically loading the airframe.

M_Gunz
04-11-2011, 06:35 AM
Originally posted by PhantomKira:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by M_Gunz:
I recommend to everyone, put FILTER on at least the pitch axis (elevator) of their stick in the stick sensitivities settings. You -will- fly smoother.

You're telling me I've been fiddling with the blankity blank input percentages all these years when all I needed was the filter! http://forums.ubi.com/images/smilies/blink.gif "$&@#*$&^@!!" http://forums.ubi.com/images/smilies/compsmash.gif http://forums.ubi.com/images/smilies/51.gif

Geez, Gunz, my flying's improved already. Thanks! http://media.ubi.com/us/forum_images/gf-glomp.gif </div></BLOCKQUOTE>

You need both! My pitch settings are 46,52,58,64,70,76,82,88,94,100 and 50% Filter. It takes a light touch but I turn better even when not well trimmed.. still do trim though.

Bremspropeller
04-11-2011, 08:04 AM
Kette, haven't seen you in a while - nice to have you back http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

What is the ultimate load-factor on the 190?
I remember the limit-load was 6g, but with a safety-factor of 2...
Is that correct? http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

Kettenhunde
04-11-2011, 09:48 AM
Thanks Brems. It is good to see you too.

FW-190A8 Standard Fighter Type is rated for 6G/12G.

BVF Standards

6G proof load factor * 2.0 Safety Factor = 12G ultimate load factor.

USA/UK standards:

6G proof load factor * 1.5 Safety Factor = 9G ultimate Load factor

http://img25.imageshack.us/img25/1742/loadfactorsafetymargint.jpg (http://img25.imageshack.us/i/loadfactorsafetymargint.jpg/)

PhantomKira
04-11-2011, 03:30 PM
Originally posted by M_Gunz:
You need both! My pitch settings are 46,52,58,64,70,76,82,88,94,100 and 50% Filter. It takes a light touch but I turn better even when not well trimmed.. still do trim though.

Yep, figured that one out already! Heh. I tend to be too harsh on the stick, rudder especially, when trying to do fine tune stuff (like shooting). My settings are: 5,10,15,20,25,30,35,48,75,100. For now. I'm still not 100% satisfied. Stinks having to haul the stick all the way back to get off the runway. It works well for BnZ though, so long as there isn't much movement required. (I fight AI a lot. Can you tell? http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif)

M_Gunz
04-11-2011, 04:46 PM
Why I run the sliders higher is to make less of a change between center and halfway to full pull. I don't move the stick with my fist but rather with light finger touch and here it does help to have an X-52! When I do turns with the default sliders and neutral trim (going into twisty-turny fight, I neutralize trim) I do a lot of stall-bleed but with sliders high I don't.

PF_Mark
08-19-2011, 07:42 PM
Coastie trying to contact you sent you a message via ubi forum want to ask you some questions


Originally posted by PF_Coastie:
I had a similar experience in a P47 Late. I am wondering if this mod does not take Altitude into consideration.

I did a qmb against two Doras and started at 7km. During the fight I made a bad pass and zoomed back up to reset for another pass (all the while still at contrail height). When I was reaching my apex at about 9km, I had to wing over to keep my eye on the Dora and my wing popped off! I was doing less than 300kph at the time. This is absolutely crazy and should NEVER happen. Only maybe if I had damage to that wing by gunfire or something(visible holes in wing). I had complete control of the fight and never even took enemy fire.

VW-IceFire
08-19-2011, 09:45 PM
Originally posted by IcyScythe:
I dunno, but to me, it seems that when I'm flying in my two favorite planes these days, the Tempest and 190 (any), I have to be WAY more cautious about turns at high speed and just diving in general.

One of the oddest things I've had happen is that I was flying along in a Tempy straight and level at 500kph (not in a dive in other words) and my wing just suddenly broke off (I had been looking at the map for a second but was still flying straight when I closed the map).

Anyone else noticing the FM being less forgiving about break speed and that sort of thing?

Also I sometimes hear "cracks" in the plane but can't see any visible damage (nothing's broken off the plane) and this'll often happen at speeds of only 400-550 kph and not in ridiculously tight turns either...

Anyone else noticing this kind of thing or am I just crazy?
The FW190 and Tempest are my two favorites as well and yes with G force modeling modeled as it is now you have to be much more careful with what you do with the airframe. It's easy at very high speed to exceed the maximum that either airframe can tolerate. Definitely a good update that 4.10 brought in IMHO.

You'll hear "cracks" because you're already reaching the maximum tolerance levels for the airframe and it's starting to flex and even warp out of place. If you do that enough it will damage the airframe under the new G force modeling. Do it enough and the maximum G force allowed decreases.

It's very well explained in the readme...better than I can do http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

I spent quit some time flying the YP-80 and Me262 at a couple of points back before the G modeling was improved. Flying those even under the old system meant thinking quite a bit about your next move. Well executed maneuvers were rewarded and knee jerk reactions and hamfisting the controls meant broken wings.

The aircraft I see breaking up the most is the Ki-84. It seems to have fairly poor tolerances for negative G forces and lots of pilots like to push that plane far past it's limits.

Although it is a bit tricky it has had one major effect for me that I've seen. Fights tend to look much more real now as human pilots are less apt to pull insane moves at high speed and you no longer see a La-7 at 600kph do a bat turn. It just isn't healthy http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif