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Snoop_Baron
06-01-2005, 05:25 PM
Several patches ago the P51 started to loose its wing and then explode during high-speed pull-ups. I did some tests and posted in this forum how to reproduce this. In a subsequent patch the P51 no longer exploded but it would still in occasion loose its wing at high speed. I posted about this problem again as it seemed almost random. At some point it was explained that this was because of a new 15G structural limit on all planes and the P51 because of its excellent high-speed elevator authority was bound to hit this limit more often than other planes. Reportedly this problem also occurs in other models with good high-speed controls such as the FW190-D9.

The other day I hosted a dogfight match on my server between P51Ds and Yak3s. During that mission I lost my wing three times while flying at high speeds (around high six hundreds kph). Each time I lost my wing before black out with out having pulled hard or all the way back on my stick. Each time I had nose down trim that I use to keep the P51 flying level. I€ve flown the P51 many times and I know to use smooth and soft control inputs to keep the Mustang from bucking. During that match I made countless high-speed dives very similar to the ones where I lost my wing. By the end of the match I could not figure out why most of the time I could pull out of high-speed dives without a problem but seemingly at random I would loose my wing at high-speeds.

After the match I thought about this problem and I decided I would test and see if I lowered my stick response curve I might be able to rid myself of this problem once and for all. I flew that day of the match with my standard response curves at 10, 20, 30, 40, 50, 60, 70, 80, 90, 100. I thought that perhaps by changing to lower numbers maybe 5, 8, 10, €¦ 100 or something like that I could get rid of this problem. When I finally found some time to test I decided the first thing I would need to do in order to validate my fix idea would be to reproduce the wing break. But when I tried to do this I found after many dives I did not encounter a single wing break. At that point I changed gears.

I thought why not change my response curves to 100 across the line and then try to expose my P51 to the highest Gs possible so that I could force my plane to hit that 15G limit every dive. So that is what I did I changed the response curves on my stick to 100 across the line. I then started the a high speed dive with full nose up trim, radiators closed, prop-pitch at 100%, and full engine power. Once I reached over 700kph I instantly pulled all the way back on the stick. Each time I did this I blacked out but I did not break a wing. I then repeated the test but this time with combat flaps engaged. Again I blacked out but did not break a single wing.

This begged the question, if when I tried to hit the 15G limit on purpose I couldn€t do it how was I hitting this limit when flying much more cautiously and trying to avoid it? The answer is I don€t know. This is what I want to find out. Am I missing something? Can one reproduce high-speed pull out wing breaks consistently? Is there perhaps some bug that is triggering a 15G spike when there shouldn€t be one?

Here are two tracks where I try to induce a wing break on pull out. The first track is without combat flaps and the second track is with combat flaps:

http://www.snoopbaron.com/aircombat/P51DPullUp.TRK
http://www.snoopbaron.com/aircombat/P51DPullUpCflaps.trk

Regards,
Snoop

OldMan____
06-01-2005, 06:18 PM
That is something.. I felt many times that when using heavy trimm down and them pulling up fastth plane would pass for a very small zone with abrupt changes and that caused me to stall a lot of times.. I imagien it can increase instant force.

biggs222
06-01-2005, 06:26 PM
call me a noob or ham-fisted whatever ud like, but ive stoped flying the P51 for this very reason... its practically a death trap in the vertical.

its a shame that the P51 was actually like that in real life, i guess.

ManicGibber
06-01-2005, 06:30 PM
I can do it every dive using QM with full tank of fuel no ammo Okinawa map. Ailerons break off then wing goes and blackout is only just starting, got 3 consecutive tracks of it happening. I didn't use any elevator trim btw.

OldMan____
06-01-2005, 06:32 PM
Well until today I never was able to loose a P51 wing witout trying it on purpouse. This is.. hard pitch and combined aileron at very high speeds.

ManicGibber
06-01-2005, 06:46 PM
Tried some more with 25% fuel load no ammo, vertical dive, 1 of the dives the wing broke before I even started to pull back, then tried another at a 45 degree dive angle and wing broke at 400-500kmh.

geetarman
06-01-2005, 06:56 PM
I am surprised at your test. With all inputs at 100, I find it very easy to break the wing off by usng prompt elevator and aileron input.

Puck1
06-01-2005, 07:42 PM
My experience has been that I only lose my wing in a p51 when I pull up at high speeds at low altitude. Above 1500 meters I think its nearly impossible to lose your wing. Below that however and especially below 1000 meters, it doesn't take much. Try it and see.

VW-IceFire
06-01-2005, 07:55 PM
Excellent test! It may be why I have no problems diving a P-51 and recovering and why I feel little fear in lossing a wing unless I'm really silly.

p1ngu666
06-01-2005, 08:00 PM
Originally posted by biggs222:
call me a noob or ham-fisted whatever ud like, but ive stoped flying the P51 for this very reason... its practically a death trap in the vertical.

its a shame that the P51 was actually like that in real life, i guess.

i think its because asked for and whined for uber highspeed elivator authority and they got it in spades.

its basicaly massivly too effective at speed, and with little damping.

for my experience u pull stick and instantly loose wing, no grey, no black its gone in a instant.

it needs tobe toned down, more rounded and less effective

WWMaxGunz
06-01-2005, 09:15 PM
See if using Filter on the pitch axis helps. If so then it may well be the stick or port
that's the problem.

NonWonderDog
06-01-2005, 09:17 PM
Setting controls to 100 across the board means *less* sensitivity at high stick deflections.

With default settings, sensitivity starts very low and ramps up (EDIT) linearly (/EDIT) towards an insanely high value the further you pull the stick. If you set all 100s, sensitivity is high and constant for the whole range. If you set all 50s it works at a constant sensitivity that's half of all 100s, but you would only get half the stick travel.

It's all very, very confusing. http://forums.ubi.com/images/smilies/blink.gif I have no idea what optimal settings would be. I've come to rather like 20 40 60 80 85 85 85 90 95 100, though.


I did some goofing around with FBView+'s little accellerometer option around the time I registered on the forums, and the results were surprising. First of all, redout starts just below 0Gs, so you can be very redded out just by flying level upside down. Blackout starts at about 4Gs, but you have to hold it for a while. It doesn't appear as though very high G-forces black you out faster.

The mustang's wings really do only fall off if you hit 15G, but they fall off *instantly* if you hit 15G. It's a bit like planes exploding instantly if you manage to hit mach 1. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif If you're hamfisted enough (and it doesn't take nearly as much as you'd think), the mustang's wings can easily fall off well before you black out.

This is all from memory, so a couple things are bound to be a bit off, and a couple of things might have changed, but what I saw was really surprising. I'm not at all sure how accurate the little accellerometer was, but it at least got 1G and -1G right.

BSS_Vidar
06-02-2005, 12:45 AM
What's funny is there weren't a lot of incidences of P-51D's loosing their wings. It happened, but not a lot. In this game however, the D model is plagued with it.

anarchy52
06-02-2005, 03:18 AM
Originally posted by BSS_Vidar:
What's funny is there weren't a lot of incidences of P-51D's loosing their wings. It happened, but not a lot. In this game however, the D model is plagued with it.

Well in reality pilots weren't pulling 15Gs very often in WWII planes. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif
I agree that large part of the problem lies in incredible effectiveness of P-51's controls at high speed.

Jaws2002
06-02-2005, 07:47 AM
Now in your tests try shooting your guns at 700km/h.
the wing vibrates and poof.
Or try hitting rudder and aileron, you'll break it every time.
Is not only the elevator alone that does it.
Speed+elevators+guns
Speed+elevator+aileron/rudder
Just like in FW 190 A.

MEGILE
06-02-2005, 08:01 AM
Originally posted by BSS_Vidar:
What's funny is there weren't a lot of incidences of P-51D's loosing their wings. It happened, but not a lot. In this game however, the D model is plagued with it.

Maybe because in real life the P-51 didn't have an elevator which allowed the pilot to pull 15Gs in a split second http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

WWMaxGunz
06-02-2005, 09:27 AM
Exactly, Megile!

Someone or some people did a posting and email campaign with Oleg to push for better
pitch control and had enough documents to make extra push. So the P-51 stick at least
for pitch was adjusted and is very easy to pull even at the highest speed. And the
control system we have is by strength, not position, when you pull your own joystick.

S! NonWonderDog!

Sensitive is like sensitive volume knob. Small turn gets big change.

Stick sliders make percent of pilot strength as percent of pull times slider amount.
So slider #10% x height 20% = .1 x .2 = 2% of pilot strength, I think 50 lb force at 100%.

What is not so obvious is you take that data and make some rough 2nd derivatives at each
point you have a slider. Does your hand know just where it is that a bit more back at
this point will get you 2x or more that last bit back you pulled for the same small move?

Couple that with spiking or just the digitizing of the pots going from one value to the
next and for one range the multiplier is one thing and then number to number it is 2x.

Easy to cross lines you don't see or feel but 1C provided something only few use.
Try and mess with the Filter slider. It helps at the least with loose parts, spiking
and jitter on a scale otherwise uncontrollable. Lots of filter will affect your moves
in a macro scale and smooth them out.

Back in 2002 there were many-many FM complaints that died when a new stick profile was
reccomended after the 1.04 patch. FM was not the real problem, it was controls. We
really do fly by wire, just not with automatic correction systems like modern jets.

geetarman
06-02-2005, 01:16 PM
My experience has been that the wing loss issue is basically resolved by using the default stick settings.

At 100 across the board though, yank on the stick in a high speed 410mph+ dive, the wings are gone!

NonWonderDog
06-02-2005, 05:03 PM
The value set on each slider, multiplied by (slider number)/10, is equivalent to the percentage of virtual stick force at 10% 20%....100% real stick deflection, right?

So... straight 100s means percent_virtual_force=real_deflection. That much is obvious, although it probably wouldn't be if we didn't have the little graphic.

This also means that default settings, 10 20 30....100, trace out a parabolic curve on a graph of real stick deflection against virtual force applied.

Oleg Maddox' Own Settings(tm), in which the sliders themselves trace out a parabolic curve, ends up looking like some kind of cubic.


Now, sensitivity is the derivative of percent virtual force with respect to real deflection. With straight 100s, sensitivity happens to be a constant 1.0. With default settings, senstitivity is a straight line equal to 2*real_deflection. This means that the stick is twice as sensitive at the edges of its travel as it is with straight 100s! In return, the stick is less sensitive between 0% and 50% deflection. Oleg's settings give a quadratic sensitivity curve in which the stick is much less sensitive between 0% and ~60% but in which the sensitivity at the end of the range is 3x higher, when compared to straight 100s.

It gets even more confusing when you realise that the amount of force needed to move the control surfaces is not a straight line. Even MORE confusing when you realise that the curves are different for each plane, each speed, stall conditions, etc. And if you use something besides a differentiable curve for stick settings it becomes nearly impossible to figure out what's going on.

Like I said, I have no idea what optimal settings would be. But I can tell you this: straight 100s != most sensitive, except near your stick's zero point.


The filter's useful to get rid of spiking, yeah. A setting of 0.1 is usually enough. I'm not sure I'd want to try to correct handling with it, though, you'd end up feeling like you were flying through mud.

LeadSpitter_
06-02-2005, 05:29 PM
i wonder why no one makes a video with udpspeed g's digital gauge showing the 109 190 me262 p51 ta152 wing snap.

Fennec_P
06-02-2005, 06:38 PM
Where can you download that program shat shows you the G load?

LeadSpitter_
06-02-2005, 10:21 PM
http://www.airwarfare.com, and http://www.simhq.com has very good device link tutorials as well as eurp snoopys airwarfare. simhq had alot of device link threads removed of exploits being used online.

Snuffly
06-02-2005, 10:24 PM
i think we owe a great big hug and sloppy kiss to snoop here for finding this bug...
Thx to snoop, this will probbaly be fixed in later patches, and he brought a little more realism in to this game.


sheet, i think he brought enough realism in the way he fly's. Good killin snoop, hope to be on YOUR six someday. ~S~ the :FI:

Snuffly
06-02-2005, 10:44 PM
btw its www.airwarfare.com (http://www.airwarfare.com)

bubiH
06-02-2005, 11:55 PM
I believe this phenomena of wings falling off online and NOT falling off offline is because the game is different in these situations. I have noticed same thing when testing combat flaps at high speeds for jamming (in 109s). They rarely jam offline but regularly online.

Just a guess as to why: the data transfer process.

Aaron_GT
06-03-2005, 03:41 AM
i wonder why no one makes a video with udpspeed g's digital gauge showing the 109 190 me262 p51 ta152 wing snap

A while back someone did an analysis using DeviceLink doing exactly this, and there was no difference in G forces at the point wing snap occured.

Aaron_GT
06-03-2005, 03:42 AM
i think we owe a great big hug and sloppy kiss to snoop here for finding this bug...

What bug? The wings snap at the same G level for all the planes. It is just that the P51's elevators are too effective.

VW-IceFire
06-03-2005, 06:53 AM
Ok...with my stick settings, I did a series of tests....I was trying to be realistic about it while also trying to be a little more hamfisted than usual. I still haven't broken the wing.

I even tried to force another Mustang chasing me to break their wing by diving to 700 and pulling back very hard....he followed me right through and shot me to pieces when we both became conscious again.

Mad_Moses
06-03-2005, 10:11 AM
I have noticed one thing for certain on the wing issue with the P-51...

On-line you can shed a wing as slow as 500kph in a simple roll if the attitude of the aircraft is level to negative in position.

Off-line you need to crank it up to over 700kph and pull hard and roll the plane simultaneously in a dive to get the same effect.

It's on-line game play bug and I hate it.

Regards,
Mad Moses

Cajun76
06-03-2005, 11:06 AM
I posted this in another thread. It's by no means absolute, I went with my impressions of how they performed in relation to each other. I tried to hit the major variants, but some are not here due to time constraints at the time.


My quick impressions, I'm not Robban. http://forums.ubi.com/images/smilies/11.gif Crimea, 5000m. Full throttle and WEP throughout. Switch to no pit for accurate speed. Let the plane build speed till flying level with no stick input, around 400-475km/h depending on a/c. Roll over, and head down. Try to get the nose vertical at about the time you hit 600 km/h. Pull back rapidly to level without stalling. Pullout usually between 700 to 800. 0 is bad, 4 is the best.

Btw, most of these match what I already had a feeling for.

<pre class="ip-ubbcode-code-pre">
Corsair D = 3
La-7 3x20mm = 2
P-40M = 1
P-39Q-10 = 1
Spit Vb = 2.5
Spit VIII = 2.5
Spit HF IXe = 1.5
P-47D-27 = 2.5
P-51D-20 = 3.5 Severe buffeting
Yak 3P = 1
Zero-21 = 1
Bf-109E = 1
Bf-109F-4 = 1
Bf-109G-2 = 1.5
Bf-109G-6A/S = 1.5
Bf-109K-4 = 1
Bf-110G-2 = 1
P-38L = 0 Never recovered
P-38J = 0 Never recovered
Fw-190A-4 = 3.5 Severe buffeting
Fw-190A-6 = 3.5 Severe buffeting
Fw-190A-9 = 3.5 Buffeting
Fw-190D-9 = 3.5 Severe buffeting
Ta-152 = 3.5 Buffeting
Go-229 = 4 Only one to rate a 4, excellent.
He-162 = 2.5
Ki-43-1a = 2 Biggest suprise, the rest were about what I expected.
Ki-84-1a = 3
Me-262 = 2</pre>



The buffeting is not due to excessive speed, it is from the rapid pullout, high AoA, introduced by the "aerodynamic" forces shaking the a/c during hard maneuvering.

These are quick impressions, so more testing may reveal a finer level of detail, but most of these seem spot on.

Buzzsaw-
06-03-2005, 01:39 PM
Salute

Historically, wing loss only happened for the P-51 when the behind the seat 85 gallon tank was more than 1/2 full. When it was too full, the center of gravity shifted, and stick reversal happened.

When the tank was less than 1/2 full, the P-51 had no issues if speed was kept below dive speed limit of 505 mph IAS. (808 kph)

The 109's also had serious problems with wing tip loss at high speed, related to use of the ailerons at speeds over 750 kph IAS. Quite a number of advisories were issued to Luftwaffe pilots warning them of these failures.

Allied pilot reports, (including reports from P-51 pilots) also noted that in steep dives 109's would lose their wings in steep dives.

In the game, for whatever reason, the P-51's have been penalized with the wing loss, whether or not the behind the seat tank is fully loaded, whereas the 109's suffer no problems with using their ailerons at speeds over 750 kph.

ManicGibber
06-03-2005, 01:43 PM
I got buffetting in a nose dive then control surfaces ripped off then wing broke, without even trying to level out, the wing broke in a 90degree dive period, offline. This is nothing to do with online/offline, I also lost a wing at 450-500km so speed has a wide margin also.

Mad_Moses
06-03-2005, 02:59 PM
Thrust me, it's an on-line issue. The wing loss effect is exaggerated at least 5 fold on-line.

I have flown the 51 at least 1000 sorties on-line, I have never lost a control surface but I have lost a ton of wings with no warning / buffeting.

I can take it up to 840kph in a shallow dive with no control input. The plane will buffet slightly at that speed. The slightest aileron input at that speed will result a lost wing, but I can get away with some elevator input as long as the plane is level. The problem is that you can slow down some 300kph (540kph) from that speed and do a snap roll and loose that wing, but only with the nose of the plane pointing towards the ground. Take into that 800kph dive again, then let it climb up to a nose up postion and yank that stick all over the place and it won't shed a wing even at 700kph as long as the nose is pointing up.

You can't take a P-51 into a 90 degree dive long enough to loose a wing without heavy negative elevator input.

The problem is the roll which doesn't generate that much G-load without elevator input and it still results in sudden wing loss without warning. This seems to happen only during on-line play.

Mad

Snoop_Baron
06-03-2005, 03:09 PM
Hi guys,

Thanks for the interesting discussion on this issue. I haven't had time to do some additional testing so I enlisted the help of a friend of mine. I pointed him to this thread and he was going to try the different combinations posted here and see if we could make sense of all of this. Just for the record I'm not claiming there is a bug (or that there isn't bug). It's to early to say. I just want to first get a clear idea as to what causes the wing breaks and then after we have answered that clearly. Then we can figure out why this is so.

So from my friends initial testing it looks like combining aileron and elevator input might be key. I will reproduce his tests on my own system this weekend so we can hopefully rule out the hardware causing any differences in results.

I will read into using devicelink so I can include some G numbers with my tracks.

I will posts our additional test results with tracks soon.

Regards,
Snoop

ManicGibber
06-03-2005, 03:25 PM
You can't take a P-51 into a 90 degree dive long enough to loose a wing without heavy negative elevator input.
I'm not clear on what you mean in the above statement Mad_Moses, I'll replay the track and see if the elevator moves significantly, I began the dive from a 90 degree roll and at 450mhp the buffetting started then at close to 500mph half elevator tore off then aileron then wing tip then opposite wing broke off.

Aaron_GT
06-03-2005, 03:26 PM
Offline I can use any combination of rudder, aileron, and elevator at 650 kph at 1000m with forces sufficient to black the pilot out for 10 seconds with no wing loss. This is using the default stick profiles.

The game uses a simplified limit for stress modelling which uses a default peak of 15G for some of the limits. Given the 109's concrete control surface response at high speed (as compared to the perhaps overdone response of the Mustang's elevator) there is no way that the 109 can pull enough Gs to shed surfaces.

There is an issue with the game but offline it doesn't seem to be any anti-Mustang crusade by Oleg (if there was we wouldn't be getting a +25lb boost Mustang III in the patch) but an issue of modelling of forces meeting simplified modelling of stresses. Online I don't know yet as I need to sort out why my firewall is stopping me linking to Hyper lobby. On previous patches when I've flown P51s I've never experienced wing break, but that might have been prior to the changes in elevator responsiveness.

Snoop_Baron
06-03-2005, 03:53 PM
Hi Snuffly http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

I'm sure I don't want you on my six bro, it's to early to say it is a bug but I think we are getting closer to figuring how to reproduce this consistently.

s!
Snoop

ManicGibber
06-03-2005, 03:58 PM
Seems I wasn't looking at the correct view when speed checking my track please accept my apologies for any confusion I may have caused. I replayed using ctrl+f1 and it shows buffeting at 850kmh, the left elevator ripping off at 1000kmh, then the left wing tip, mid section and flap at 1007kmh, and at 1024kmh the right wing tip, aileron rip off. The elevator was in a negative angle for the whole dive with slight movements +- but never coming back to 0 degrees, the plane broke up purely from speed, friction, vibration, not from G forces.

Snoop_Baron
06-03-2005, 04:01 PM
It's definetly not some sort of anti-Mustang crusade. It could very well be that there is no bug. If it there is a bug it is just that a programming mistake, no conspiracies here please http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

I talked to my friend on the phone and he thinks that ailerons are the main culprit. You may be able to induce wing-breaks with just ailerons and little or no elevator. Altitude also has a lot to do with it. He noticed that the higher the altitude the harder it was to break off a wing. And the lower the altitude the easier it was to break the wing. For example 500 meters seemed to be worse than 1000 meters.

One test I'm keen to try is to set my elevator response to zero all the way across axis then use trim to get into a dive and pick up speed at low altitude and then see if ailerons alone can break a wing off.

Regards,
Snoop

Cajun76
06-03-2005, 05:48 PM
Originally posted by ManicGibber:
Seems I wasn't looking at the correct view when speed checking my track please accept my apologies for any confusion I may have caused. I replayed using ctrl+f1 and it shows buffeting at 850kmh, the left elevator ripping off at 1000kmh, then the left wing tip, mid section and flap at 1007kmh, and at 1024kmh the right wing tip, aileron rip off. The elevator was in a negative angle for the whole dive with slight movements +- but never coming back to 0 degrees, the plane broke up purely from speed, friction, vibration, not from G forces.

The discussion is not terminal dive speed, even the mighty P-47 will break up at a high enough speed. Problem people (like me) have encountered is the wing snap, even at a relatively low dive speeds when maneuvering. My control inputs are rather low at the low end because I fly the P-47 so much, and I still ripped the wing off the other day, diving and rolling to track someone.

The wing popping off made no sense until I read this thread, and heard about the ailerons. Much more sense now, and there might be some bug or something where the ailerons are not balanced together.

As ya'll know, as one aileron is deflected up, the other is deflected down. They should have almost the same effectiveness, inducing roll. What if the up deflected (either side) has much more power than it's opposite. Or the opposite, same effect. That might be enough stress to take the wing off at high speed. I think the sim's engine automatically cuts roll in half with an aileron gone, so we might not see this effect when a/c are damaged and only have one.

Just thinking out loud..... http://forums.ubi.com/images/smilies/35.gif

ManicGibber
06-03-2005, 06:26 PM
There is more drag induced by one aileron in relation to the other, however I don't know enough about lift/drag to be able to work out if it is when the aileron is up or when it is in the down position, I seem to recall from years past (when I used to fly radio controlled gliders and powered planes) that the aileron has more drag when down than it has when it is up. This might not even be modelled in the sim though. Also from my own experimenting it is easier to rip off wing control surfaces at lower altitudes 3000m and below, above this and I found I couldn't break a wing so far.

TX-EcoDragon
06-03-2005, 06:57 PM
Yes Manic, the aileron going down in effect increases the wing camber, which increases lift on that wing as it moves down from the neutral position, and therefore drag increases. . . the aileron going up leads to a decrease in lift and drag. This is why we see adverse yaw when rolling without coordinated rudder. The sim doesn't really model this though we do have a little bit of adverse yaw.

ManicGibber
06-03-2005, 07:00 PM
Did some more testing and I cant break the wing if I stay above 1700m in vertical dive at 850kmh and quickly level out, speed taken from speed bar and using full back stick to level out. I think it is a combination of height and velocity and control sensitivity, ie the higher you are above 1700m or thereabouts the faster you can go and the rougher you can be on the controls. Below 1700m you have to be more sensitive with controls especially at high speeds.

TX-EcoDragon
06-03-2005, 07:22 PM
Originally posted by Cajun76:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by ManicGibber:
Seems I wasn't looking at the correct view when speed checking my track please accept my apologies for any confusion I may have caused. I replayed using ctrl+f1 and it shows buffeting at 850kmh, the left elevator ripping off at 1000kmh, then the left wing tip, mid section and flap at 1007kmh, and at 1024kmh the right wing tip, aileron rip off. The elevator was in a negative angle for the whole dive with slight movements +- but never coming back to 0 degrees, the plane broke up purely from speed, friction, vibration, not from G forces.

The discussion is not terminal dive speed, even the mighty P-47 will break up at a high enough speed. Problem people (like me) have encountered is the wing snap, even at a relatively low dive speeds when maneuvering. My control inputs are rather low at the low end because I fly the P-47 so much, and I still ripped the wing off the other day, diving and rolling to track someone.

The wing popping off made no sense until I read this thread, and heard about the ailerons. Much more sense now, and there might be some bug or something where the ailerons are not balanced together.

As ya'll know, as one aileron is deflected up, the other is deflected down. They should have almost the same effectiveness, inducing roll. What if the up deflected (either side) has much more power than it's opposite. Or the opposite, same effect. That might be enough stress to take the wing off at high speed. I think the sim's engine automatically cuts roll in half with an aileron gone, so we might not see this effect when a/c are damaged and only have one.

Just thinking out loud..... http://forums.ubi.com/images/smilies/35.gif </div></BLOCKQUOTE>


The forces that are imposed on a wing by aileron inputs can be very high. Many people don't really take this into consideration when looking at the limit load factors of an aircraft. This is why pilots must know maneuvering speed for their current aircraft weight. This is the maximal indicated airspeed at which full and abrupt use of the elevator control (in the aft direction) can be made that will not result in an airframe overstress. The idea is that when at or below the maneuvering speed the aircraft will not pull more than the approved G loading without an accelerated stall developing first. When at speeds above this value (denoted Va) the aircraft will not enter an accelerated stall until a G load greater than that approved is encountered . . . and at this point airframe failure may have occurred.

Most all pilots know this, but many do not know the details of this value, and that in most cases (unless otherwise stated) Va ONLY applies to the elevator control in the aft direction, meaning that if you are at Va but push the elevator fully and abruptly forward, you may very well overstress the aircraft, if you are at Va and you pull back WHILE rolling the aircraft, you may very well overstress the aircraft . . . etc. So to a pilot that expects to operate in this region it is important to know if your Va is the sort that applies to all surfaces, and surfaces used in conjunction with one another, or if it is the more common aft elevator only. Generally in the instances where the Va is of the standard variety pilots are (or should be) advised to use 2/3 Va for full and abrupt use of multiple surfaces at the same time.

Imagine an aircraft pulling it€s limit load factor of say, 7G, now imagine that while it sustains this that it begins to roll, neither the G meter nor the pilot will perceive the loads imposed on the wing, though clearly the wing with the lowered aileron experiences loads higher than that felt by the pilot, or the accelerometer (if so equipped). It turns out that these forces are not fully known, but what is known is that they can be quite high, and that they are not uniformly supported by the wing (leading to localized areas of the highest stress).


So the point is, aileron inputs certainly can impose significant loads on the aircraft in particular when already under load.

I wouldn't call the online DM simplified since it is perhaps more accurate, why they are different I don't know. What I can say is the real P-51 is not so light in pitch as it is in the sim. . . and I feel that the propensity for people to black out in it is simply due to the fact that the available G is so high and the stick input required for it is so low. The lack of harmony between the aileron and elevator in the sim 51 makes this a little more unnerving. Oh and I should mention that this has been looked at by many who found that the failure point of 15G held true for all planes, keep in mind that none of these aircraft were expected to survive such a high loading. Generally though the limit load factors that are specified for an aircraft are not the actual point at which damage will occur, rather they contain a safety margin which is often 1.5 times the approved load factor. What this means is an aircraft approved for 7G is expected to fail no sooner than at 10.5G, but this is a variable depending who is doing the certifying.
For example, in some modern day instances the limit is nothing near the actual load limit, such as in modern aerobatic aircraft and some high performance composite cross country GA aircraft. In these cases the wing may not fail even at all unless one of the (usually two) spars is cut! These machines may go up to as high as 20G! On many test rigs the machine will not be able to break the undamaged wing at all! Of course the FAA wont touch such a loading for certification purposes so it still slaps a 10G limit on many such aircraft.

Fennec_P
06-03-2005, 07:51 PM
Ok, I finally got this devicelink thing to work, and I had to try out the wingbreak thing.

Explanation of test.

I dived various planes from 3000m. I did pull-outs from 650, 700, 750 and 800km/h for each plane. In the pull-outs, I smoothly increased the load factor (using time compression to slow it down), and made a note at the load at which the wing broke off.

I'll not write the results; suffice it to say that the FW190D9, FW-190A4, P-51, A6M2, P-47D27 and Bf-109G2 all have wingbreak at the exact same point. All in all, the test was kinda pointless.

It's not 15G, but rather in 13-14 range. Speed did not affect the failure point; breakage occured at the same load whether at 700, 750, or 800km/h on all planes.

You can sustain 13G for a few moments before breakage. 14G will destroy the wing almost immediately. However, you can occasionaly survive loads of 15G+, but only for 1/2 second or less. But in almost all cases, it just breaks immediately at 14G.

Even a momentary stick jerk that makes your G-load spike above 15G can kill you. This makes it extremely important to smoothly pull the stick back during a high-speed pullout. Using just trim for pullout is also a good idea, as it removes the possibility of an accidental ham-fist.

The only differences between the planes was the speeds at which wing breakage was possible (due to stalling), and how much trim was required to do it.

For example, P-51 can break wings at speed as low as 650, because of it's over-responsive controls. FW-190 cannot wingbreak at 650, because it stalls. At higher speeds it requires some trim, because the elevator gets slightly heavy. A6M and 109G2 require almost full trim to do wingbreak, because the controls get so heavy.

I did not try wingbreak at higher altitudes, but would assume it's the same 13-14G. Same with aileron inputs; I doubt it would affect it.

On blackout: The onset of blackout occurs so slowly that it is completely useless for figuring G-load. In all cases, I got wingbreak long before the blackout covered my screen. In doing the trials I found I could easily do 12-13G 70 degree pullouts without even blacking out completely.

All in all, it's a simplified model, and not very realistic. Wingbreak should occur at different loads in different planes. Also, speed should affect the maximum load factor due to wing twisting (higher speed=less allowable G). Here is keeping my fingers crossed for 'next sim'.

One further note: The program I am using, UPDSpeed, does not work online. According to devicelink.txt in PF directory, PF disables this data when playing in an online mode. I don't know if there is a way around this, though.

Snoop_Baron
06-03-2005, 08:02 PM
Thanks for some very informative posts EcoDragon. I definetly believe that the 15G limit applies to all planes as Oleg has told us. I'm looking forward to testing this some more. This is all begining to make a lot more sense.

In the past I was always focusing on keeping my elevator inputs smooth and slow and not using any nose up trim to prevent wing-breaks but I didn't even suspect that the ailerons might have such a large effect. I hope with some testing we will all be able to avoid wing breaks by paying special attention to our aileron inputs when pulling out of high speed dives at low altitudes. This will take away the frustration many have felt from feeling helpless in avoiding what *seemed* like random wing-breaks.

Could you elaborate a little bit more on this line:

"The lack of harmony between the aileron and elevator in the sim 51 makes this a little more unnerving."

Thanks,
Snoop

Snoop_Baron
06-03-2005, 08:08 PM
Hi Fennec,

Thanks for the test. During your tests could you reach 14Gs in the P51 with just elevator input and no aileron input or did it require a mix of the two? I ask because it seems that I was not hitting the 14G limit while pulling out as hard and as abruptly as I could when going above 700kph (with 25% fuel) in the P51D?

It looks like flying with devicelink while training offline would be a great way to train yourself to avoid these limits. I have to give that a try http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Regards,
Snoop

Fennec_P
06-03-2005, 08:15 PM
No aileron, no. Just wings level.

At 800km/h, you can spike it almost 20G with elevator alone. This is at low alt mind you, might not be as responsive at high alt.

Cool program, that devicelink. Also useful to give you a fuel gauge for planes that lack one.

Used this tutorial: http://www.simhq.com/cgi-bin/ultimatebb.cgi?ubb=print_topic;f=98;t=011755

p1ngu666
06-03-2005, 08:35 PM
i think all or most of the planes stiffen up as the alt goes higher
zero and hurri come to mind

ive found p51 tobe fairly easy and forgiving at really high alt, surprisingly so really
i include lowspeed stuff especialy in that statement

Snoop_Baron
06-03-2005, 08:38 PM
Hi Fennec,

That must be it I was probably not low enough during my tests for elevators alone to do the job. I don't remember the exact altitude but I think I was atleast above 1km in altitude.

Thanks for the link!

s!
Snoop

NonWonderDog
06-03-2005, 08:39 PM
Using ailerons would completely screw up the test if the accellerometer measures forces felt in the cockpit.

If you use ailerons and elevator at the same time, you should be able to load one wing with greater than 14G while the accellerometer reads less. Elevator+ailerons=BAD at high speed, as EcoDragon so eloquently pointed out.

I seem to remember being able to hit over 20G as well, back when I tested this. That probably shouldn't happen, but adding a bit of filtering in your joystick settings helps.

WWMaxGunz
06-03-2005, 09:02 PM
S! Fennec, excellent post as I've come to see from you.

UDPSpeed used to run for me on track playback so you can try online tracks with it though
I only remember using full mission track files and offline those may differ in action.

How long it took to black out; you were running in slow-mo, maybe blackout time vs G's
can be more understood.

Also with time at G's to wing break we must be seeing airframe stress asked for so long
if battle damage will lessen this. It is a realism factor to have it at all that I only
remember seeing before in the Red Baron series (with wings creaking) but may be in others.

TX-EcoDragon
06-03-2005, 11:21 PM
Thanks for the info Fennec!

Snoop Baron,

What I meant was that the in game P-51 has very different feel on the aileron compared to the elevator. The aileron forces ramp up and response becomes a bit more sluggish at speed, while the elevator forces are very light, and very responsive and remain more or less the same as speed changes. The real 51 on the other hand has smoother and heavier elevator feel that reacts more similarly to the aileron, and that firms up at speed to the point of becoming a "two-hander" for many pilots.



Fennec said:

"On blackout: The onset of blackout occurs so slowly that it is completely useless for figuring G-load. In all cases, I got wingbreak long before the blackout covered my screen. In doing the trials I found I could easily do 12-13G 70 degree pullouts without even blacking out completely"

It is correct that there is delay in the visual effects of the blackout, and correct that airframe damage can occur without any visual symtoms of blackout. This is because there is an oxygen reserve in the body that provides a few seconds of time where the body can sustain extreme G loads before any visual symptoms or GILOC. The airframe has no such buffer zone. . .15G is 15G. Also keep in mind that pulling high G means the duration of exposure is reduced, so in some cases higher Gs may actually be easier to tolerate than lower G loading that lasts longer. (provided the aircraft can handle it)

Here is a diagram of the typical physiological responses relative to G loads and duration of exposure. Note that for the first 5 seconds of G exposure there are no visual symptoms no matter the G loading.

http://www.vnh.org/FSManual/02/Images/fig2.3.gif

WWMaxGunz
06-04-2005, 05:09 AM
OTOH, you get hit with a big change in G very suddenly and something else can happen.
Your brain can hit the inside of your skull the same as getting punched or banging
your head hard and you can go lights out that way. We have one guy who blacked out
on a seat ejection and swears you can get instant blackout!

Then there's the long slow blackout when you've been drinking too long......

MoeLarryCheese
06-04-2005, 05:31 AM
Long thread dancing around the obvious.

P-51s (F-51s) gave the Communists a pasting
during the Korean conflict.

Combining the obvious Russian bias in this sim
with the current fad in dissing all things
American and you get the answer.

Down playing the P-51's superiority is bodering on
a European fad in this community. Oleg just
went along with the times.

Don't expect a fix people.
The P-51 wil continue to explode, it's just
the thing to do these days.

MLC

Badsight.
06-04-2005, 07:01 AM
without MoeLarryCheese we never would have gotten to the bottem of this

& to think people tried doing tests with their silly "devicelink"

pffft to you testers & your desire for hard numbers , all you need is moe here

be sure http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

Badsight.
06-04-2005, 07:07 AM
Originally posted by Fennec_P:
P-51 can break wings at speed as low as 650, because of it's over-responsive controls. . me an Moe here dont believe they are too good , just look at how badly the P-51 does in turning fights

right Moe ?

Hetzer_II
06-04-2005, 07:12 AM
I flew the p51 yesterday for the hole evening on warclouds.. i didnt even managed one time to loose a wing.. i only can if i want..

so maybe we have some whining trolls here?
same with D9... if you want you can loose youre wing.. but if i dont want to.. i dont loose it..

just my 2 cents..

Kurfurst__
06-04-2005, 09:31 AM
Originally posted by Aaron_GT:
Given the 109's concrete control surface response at high speed (as compared to the perhaps overdone response of the Mustang's elevator) there is no way that the 109 can pull enough Gs to shed surfaces.

Given that in real life the elevator stick force gradient of the Mustang and the Bf 109 was very similiar, 20lbs/G, ie. both were designed with rather heavy elevators, it`s either both should shred the wings on neither. That is not so in the game, the pilot could pull a lot more Gs on the P-51, and exceed the critical G-load..

Looks like the Mustang-fans overwhined themselves, they pushed Oleg so hard to have 'superior' high speed pitch manouveribilty... until they finally got what they asked for. Had they put up with a historical Mustang with it`s heavy elevator forces, which is a matter of recod, there wouldn`t be wing shreddings, as the game doesn`t model random structural failures that hurt a few types on occasion. To me it appears the problem is that the 109 comes with a bit too heavy elevators (see other threads), the Mustang with a bit too light ones.

Snoop_Baron
06-04-2005, 09:32 AM
Hi EcoDragon,

That makes a lot of sense. I would love to have a more realistic elevator in the P51!

MoeLarryCheese,

Please take your ignorant conspiracy theories somewhere else. Your are riddiculous.

Hetzer,

Please don't start name calling. I have also flown the P51 many days online without a single wing break. When I first started this thread it seemed wing breaks were random to me. It looks now that it was a combination of altitude + ailerons that caused certain pull outs to fail while most went fine. Most of the time I wasn't touching my ailerons or going that low. The event that prompoted me to post was a squad df match where I lost my wing three times seemingly at random. If you go to the Fighting-Irish website you can find screenshots of that match including two with my wings snapped off (thanks to Genosses sense of humor http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif ). We also have a track of the entire match on our forum.

Regards,
Snoop

Snoop_Baron
06-04-2005, 09:38 AM
To see the screenshots click on the bottom icon on the right hand side of our home page to get to the screen shot archive. Then click on the May 2005 screen shot to list the albums for that month. Then click on the last album in May (picutre of a Yak 3). Then on pages 1 and 3 you'll see my P51 with the wing snapped off. I'm using a pirate paint scheme.

Regards,
Snoop

Hetzer_II
06-04-2005, 09:53 AM
@snoop...

if you read again.. i didnt say any name..

But its like it is: if you fly the 51 gently than nothing happens.. Or maybe i just had luck yesterday.. i dont know i will try again tomorrow...

greets

Snoop_Baron
06-04-2005, 12:05 PM
Hetzer this is what I was referring to:


Originally posted by Hetzer_II:
so maybe we have some whining trolls here?


This thread has been productive and clean other than MLC and I don't want it to degrade.

Regards,
Snoop

Aaron_GT
06-04-2005, 02:57 PM
I tried the P51 online today in a server (I suppose the online component can be tested by hosting your own LAN server and joining it, but there might be differences with that set up) and try as I might (diving from 4000m and pulling hard maneouvers using all three control axes) I couldn't get a wing to pull off with the default control gradients.

WWMaxGunz
06-04-2005, 03:36 PM
Could the seeming random breaks be due to battle damage you may not have seen but was
still there? A few bullet hits won't always get the change in graphic you would see.
That is one thing no test so far does or can really since how do you conrol how much
damage is given?

Snoop_Baron
06-04-2005, 03:54 PM
Hi Aaron,

How high up where you when you began the pull hard manuvers? Try diving down to 1km or bellow and then pulling hard manuvers. It seems that if you are high enough you can be as ham fisted as you want to be and not break a wing. I plan on doing more testing tomorrow online and offline. Although, I don't think online is any different from offline, but I will test both just incase.

Max,

Most of my past wing breaks have been on an undamaged mustang. But who knows perhaps G tolerance is modeled to go down as the plane is damaged, that would make sense.

Thanks to the explanations above I now understand how ailerons contribute to airframe stress and Gs. Could someone explain to me why you can be more ham fisted at higher altitudes. Is it due to reduce controls at high alitude? Does it have to do with air thickness? I know very little aeronautics.

Regards,
Snoop

TX-EcoDragon
06-04-2005, 04:17 PM
Originally posted by Snoop_Baron:
Hi Aaron,

How high up where you when you began the pull hard manuvers? Try diving down to 1km or bellow and then pulling hard manuvers. It seems that if you are high enough you can be as ham fisted as you want to be and not break a wing. I plan on doing more testing tomorrow online and offline. Although, I don't think online is any different from offline, but I will test both just incase.

Max,

Most of my past wing breaks have been on an undamaged mustang. But who knows perhaps G tolerance is modeled to go down as the plane is damaged, that would make sense.

Thanks to the explanations above I now understand how ailerons contribute to airframe stress and Gs. Could someone explain to me why you can be more ham fisted at higher altitudes. Is it due to reduce controls at high alitude? Does it have to do with air thickness? I know very little aeronautics.

Regards,
Snoop

Available G will go down as aerodynamic ability to generate lift goes down (two ways of saying the same thing). Generally for a given G loading you will need a higher angle of attack at higher altitude if indicated airspeed is held constant. The wing still stalls at the same angle of attack (more or less), and the drag is still elevated at higher angle of attack, and there is also less power being produced by the engine which when these factors combine you can see that there will be a decrese in indicated airspeeds, and a decreases in the overall available G for a given airspeed. Also a potential factor is that the buffetting you see and hear in the sim increases a bit at altitude for a given G so perhaps when you encounter the edge of the envelope it is more obvious and you ease up sooner.

Aaron_GT
06-04-2005, 05:11 PM
Hi Aaron,

How high up where you when you began the pull hard manuvers?

3000ft or lower. For me it seems that 500mph is the critical speed required before manoeuvering will cause a wing to come off (with either default stick sensitivity or 100s across the board).

Testing seems to show planes fall into three categories:

1. Ones that fall apart before you can get to 500mph (e.g. Gladiator).
2. Ones with concrete elevators (e.g. Spitfire, 109). If you yank back the stick at 500mph indicated at 3000 ft these do not deflect the elevators fully (stick force limiting) and come out of the dive gradually.
3. Ones for which the elevator response is such that a swift pull on the stick makes the attitude change rapidly for about 1/2 second before the wing breaks off. Examples are the P51 and Me 163.

I have yet to find a plane that has ineffective elevators and sheds wings. So that suggests to me its a G limit as Fennec found.

WWMaxGunz
06-05-2005, 01:11 AM
Originally posted by Snoop_Baron:

Max,

Most of my past wing breaks have been on an undamaged mustang. But who knows perhaps G tolerance is modeled to go down as the plane is damaged, that would make sense.

Even if it would not be as drastic as it would seem (a single MG hole in the spar and now
maybe 5 or 6 G's is too much, perhaps that is too quick?) to me the confirm of such detail
in the model (so maybe the one hole reduces by 1 G now?) would still be news and has been
asked for long ago. It has also been noted long ago we maybe got it, but no confirm.


Thanks to the explanations above I now understand how ailerons contribute to airframe stress and Gs. Could someone explain to me why you can be more ham fisted at higher altitudes. Is it due to reduce controls at high alitude? Does it have to do with air thickness? I know very little aeronautics.

Regards,
Snoop

Higher altitudes... sound travels through air slower as air gets thinner. Another way to
say that is the mach speed reduces as you go up. And as a plane comes closer to mach speed,
even over one half but definitely by 70 percent the effects of compression become noticeable.
For sure it may not be the speed of the plane itself, but air displaced by the plane body
and wings is forced to travel relative to those parts faster than the speed of the overall
plane itself, so you get shockwaves even before the whole plane reaches sound speed.
The shockwaves start out weak, they form and go, form and go, fast and make shaking/vibration.

At the back edges they will form and break and as speed increases, they move up and get
stronger. When they do this on the ailerons, the cause vibration of the stick even in
modern jets, at least Gulfstream, Cessna and Lear in the late 80's that I know from classes
as part of work I had and the term they all knew it was "aileron buzz", could be felt even
in planes with hydraulic controls but worse in the Lear 35 (and earlier) that uses cables.
In those planes, you get the buzz, you find ways to slow down. Those are not supersonic
planes just as the WWII planes are not.

Before even then there is the resistance to control motions. I have a P-39N-1 chart that
shows on elevator the effects of compression on stick force at 15,000 ft starting down at
300 mph and by 400 mph the force is already double and the curve goes steeply upward from
there. 420 mph, 3x and 440 mph, 5x. But that is not only calculated compression but they
note bulging of surfaces, however slight be sure but not smooth whether wing or what I don't
know. The action of air there is enough to temporarily bend the metal at least small amount.
I wish I had more pages that might say exactly what they mean. The document was posted here
before, I zoom the image and somewhat clearly (but not perfect) it looks like it says
NACA ACR No. 5I13.

Notice that the compressive forces would affect that plane at even slower TAS higher up.
Since IAS to TAS difference widens also as you rise, the pilot would find the stick harder
to pull back at even lower IAS that just by proportion of altitudes. But right now I have
been typing long already and this is dialup, the connect dies so someone else can find the
IAS of 400 mph at 15,000 ft, the corresponding mach at say 8 km alt and the IAS at that
height and speed? I think it would not be totally as expected by many!

Buzzsaw-
06-05-2005, 12:13 PM
Salute

Still waiting for Luftwhiners to explain why Wingtip loss on 109's due to use of ailerons at high speed is not modelled.

---------------

Flying Limitations of the Me 109 G (from: Technical Instructions of the Generalluftzeugmeister, Berlin, 28th August 1942.)

Reference Me 109 - wing breakages. Owing to continually recurring accidents caused by wing breakages in Me 109 aircraft attention is drawn to the following:

.......(1) The maximum permissible indicated airspeeds in the different heights are not being observed and are widely exceeded. On the basis of evidence which is now available the speed limitations ordered by teleprint message GL/6 No. 2428/41 of 10.6.41 are cancelled and replaced by the following data:


Up to 3 km (9,842 ft.) 750 km/h. (466 m.p.h.)
At 5 km (16,404 ft) 700 km/h. (435 m.p.h.)
At 7 km (22,965 ft) 575 km/h. (357 m.p.h.)
At 9 km (29,527 ft) 450 km/h. (280 m.p.h.)
At 11 km (36,089 ft) 400 km/h. (248 m.p.h.)

.......These limitations are valid for the time being for all building series including the Me 109 G. A corresponding notice is to be placed upon all air-speed indicators in aircraft.

.......(2) Yawing in a dive leads to high one-sided wing stresses which, under certain circumstances, the wing tip cannot support. When a yawing condition is recognised the dive is to be broken off without exercising force. In a flying condition of yawing and turning at the same time correction must be made with the rudder and not the ailerons. The condition of wing tips is to be examined and checked with TAGL. Bf 109 Nos. 5/41 and 436/41.

.......(3) Unintentional unlocking of the undercarriage in a dive leads also - especially if only one side unlocks - to high wing stresses. Observation and the carrying out of TAGL. No. 11/42 and the following numbers is, therefore specially important.
Note. Trouble has been experienced owing to undercarriage unlocking in a dive and a modification has been brought out to prevent this.

.......The dive speed limits listed above are also to be found in Vorl¤ufige Fluggenehmigung BF 109 G-2 and G-6

Dive limitations from: Bf 109 G-2, G-4, G-6 Bedienungsvorschrift, June 1943 edition

.......Dive: Adjust trim in such a way that the airplane can be held in a dive. The elevator forces and tailplane loads become great at high speeds. The tailplane adjustment must work perfectly; otherwise shifting of the tailplane is possible.
Sturzflug: Trimming so einstellen daß das Flugzeug durch Drücken im Sturzflug gehalten werden kann. Die H¶henruderkr¤fte und Flossenbelastungen werden bei hoher Fahrt sehr groß. Hemmung der Flossen verstellung muß einwandfrei arbeiten; sonst ist Selbst verstellung der Flosse m¶glich.

.......Maximum diving speed 750 km/h. Hard aileron manipulation while diving leads to failure, particularly when pulling out. H¶chstzul¤ssige Sturzfluggeschwindigkeit 750 km/h. Harte querruder bet¤tigung im Sturz und besonders beim Abfangen führt zum Bruch.

--------------

LeadSpitter_
06-05-2005, 12:24 PM
hyperion or snoopy, can anyone tell me the trimmed level flight G's in the p-51 and fw190 at 540-560kmp.

Im wondering the p51 has to be trimmed alot 10-11 clicks to fly perfectly level and the 190 it needs about 3-5 forward clicks at 560, is that creating more g's on the elevator.

I have just seen a couple people say the wings are all breaking at the same ammount of g's but have no seen any detail information showing the udpspeed charts and g's.

Maybe that adds to the G's

Aaron_GT
06-05-2005, 12:31 PM
but have no seen any detail information showing the udpspeed charts and g's.

I thought Fennec posted those figures?

Aaron_GT
06-05-2005, 12:39 PM
Still waiting for Luftwhiners to explain why Wingtip loss on 109's due to use of ailerons at high speed is not modelled.

1. Surely it is for Oleg to explain, since Oleg's team creates the 109 in the game, not the Luftwhiners.

2. The damage from aerodynamic stress is simply modelled it seems, with wingtips not being one of those things that comes off individually. Oleg says it will be more detailed in BoB. Likely the current game engine cannot cope with things of this detail any more than it models jamming on unboosted P51B guns or issues with gear doors opening. Or a whole host of issues with dozens and dozens of the planes in the game of every nation. I think we'll have to wait for BoB.

At the moment my rough analysis (no DeviceLink) seems to indicate that at 500mph indicated at 3000ft there are many planes which shed wings, and all are characterised by highly responsive controls at high speed. It may be that the P51's elevator is too effective at high speed and should be toned down. Or perhaps there need to be changes to how quickly attitude changes can happen even beyond this, but only Oleg can say if the game core will get changed. It might be that the 4.0 FM might introduce changes in this respect. If we wait 2 weeks who knows.

WWMaxGunz
06-05-2005, 02:53 PM
Oleg has been good enough not to visit a host of problems on planes that were discovered
and subsequently fixed, like the varnish of LaGG's coming from one factory for a period
of time only and being noted in histories not characterizing all LaGG-3's in the game.

Oleg should have a complete history of LW restrictions, etc. We have the 190A-4 with
reduced boost because of the timing of appearance and fix and front the plane was set
in the game for even though later on it was raised to 1.42 ATA and that is correct to
have the reduced boost model in the game. Oleg has the resources to make that decision
and yet now from an August 1942 paper alone all 109's should change? Are there any
later papers saying different? I know that Gunther Rall stated inability to dive away
from P-47's and P-51's due to those having stronger construction and so higher maximum
dive speeds (but the numbers he gave were inflated by the instruments of the time not
being able to handle compression) which I believe but complete historic data is what
Oleg goes by.

As Aaron says, the question is Olegs' department. Oleg may know more than what has
been presented. It would not be the first time. But send the data in anyway because
maybe there has been oversight and a change is due!

TX-EcoDragon
06-05-2005, 04:16 PM
Originally posted by LeadSpitter_:
hyperion or snoopy, can anyone tell me the trimmed level flight G's in the p-51 and fw190 at 540-560kmp.

Im wondering the p51 has to be trimmed alot 10-11 clicks to fly perfectly level and the 190 it needs about 3-5 forward clicks at 560, is that creating more g's on the elevator.

I have just seen a couple people say the wings are all breaking at the same ammount of g's but have no seen any detail information showing the udpspeed charts and g's.

Maybe that adds to the G's



Technically the answer is in the question . . . at level flight you are at 1G. Now what complicates this is the position of the CG. If the center of gravity and the center of lift where in the same place the tail would not really need to generate lift in either the up or down direction, but this would lead to an extremely pitch unstable aircraft. In conventional aircraft the center of gravity is in front of the center of lift, and the tail surfaces generate their lift in the downward direction to oppose the natural nose drop tendency. The summation of the lift, weight, and lever imposed forces all balance out in level flight, but if the CG is far forward the nose drop tendency will be stronger, and thusly the downward lift of the tail must be higher to oppose it, and we can see that this will also increase the load on the wing somewhat . . . though I don't think it is by any significant amount in normal designs. The in-game P-51 feels like it has an aft CG which will increase pitch response, decrease pitch stability, increase flight efficiency and top speed somewhat, but in general this will make it easier to over-g a wing given the reduction in pitch stability and the lower stick forces/G. Your description of more forward trim supports this, and if this were the real world, this would actually lead to a reduction in static loadings on the aircraft since nose down trim equates to a reduction in the forces on the wing and tail, not an increase. I seriously doubt this level of detail is in the sim, in particular since it's not really even considered all that important in the real world of aviation.

Snoop_Baron
06-06-2005, 05:55 PM
I'm going to be gone on vacation for the next several weeks so I won't be able to post or sim until I get back. But I feel a whole lot better about this now than before and I think I'll be able to avoid wing-breaks consistently (or so I hope http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif ). I'm also looking forward to re-testing all this when the new FM comes out.

Regards,
Snoop

Bull_dog_
06-07-2005, 11:46 AM
Since it was locked for starting a new thread on the same subject...my reply

Posted Mon June 06 2005 18:19
Wanted to start a new thread because the other one was getting so long.

I fly the mustang quite a bit, online and offline, and I've been very frustrated with the wing breaking phenomenom so when the other thread started and I read things about people not being able to get the wings to break off...i thought hogwash...i'll go see for myself.

I set up a little bit of testing on B, C, and both D models...nothing too scientific but this is how i did it..

Okinawa map starting at 5000 meters, offline, i selected each mustand and dove at as steep of angle as i could with trim left in its original position. I brought the plane to between 750km/hr but less than 800km/hr and pulled the stick back to maximum deflection. I would then climb up and repeat...each time i'd get a little lower and lower at pull out.

My findings were that I had to get to approximately the 1000 meter mark in the D models to break the wings and I did once break a B model at just a bit less than 2000 meters but I could never break a wing higher than that and I never broke a D model above 1300 meters.

I have had my most difficulty online and felt the problem was worse online so I whipped up an online map and created an airstart test map of the Ardennes summer map and climbed to about 4000 meters in the D and C models and dove to the 750km/hr mark...or about 2000+ meters and my wings broke off. No need to repeat since I was dead.

Because of the time involved with climbing, testing different maps etc, I only did this a little online, so far, so I don't know how high you have to go online before wings fall off. In addition, I did not create full mission builder offline maps to test and it has occurred to me that this issue might be more map related...i have broken wings most easily in P-51's but also in Fw's, Ki's and even once in a Corsair. I made no tracks since this is all preliminary stuff and I really don't have the time nor gumption to continue testing. I have the answers to what I was looking for.

I will likely, for my own benefit, try to establish that upper limit for online play because that is where I have my most difficutly. There is no doubt that with careful flying you can avoid wing breakage at high speeds online, but you can not engage and actively pursue/fight and adversary at really high speed so....yes it is possible to break a wing online and offline...it appears to me that the online situation is much more likely but I don't know why. I keep my trim downwards at high speeds, online, so as to help reduce the risk of over controlling....now what I'm really wondering is whether or not there is a difference in control effectiveness online vs offline and if so...what else is different?

Interesting thought and question...maybe that is why certain IL2 compare programs and testing yield varying results...maybe it is map related.

Enough for now.

TacticalYak3
06-09-2005, 12:38 PM
Man Snoop you're not still sore from me killing all your Mustang buddies a couple of weeks ago in my sexy little Yak-3, are you mate? http://forums.ubi.com/images/smilies/88.gif [TacticalS! runs away and hides - yes, mom, he's a coward]