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CaptJodan
12-07-2004, 10:23 PM
I'm sure that this subject has been broached before, but I can't for the life of me find it.

Genuine question here, not out to flame or war-monger, but in relation to the P-51's wings, is there a documented history for them to simply rip off so easily at speeds of about 700 kph (when pulling out of a dive, for instance)? More to the point, I suppose, is this phenomenon MORE COMMON in the P-51 than any other aircraft in WWII? I've never seen anything about this, but was wondering if this is something burried deep in the recesses of some archive.

I just figure if this was a common occurance...at least moreso than other AC, that it would have been better documented.

CaptJodan
12-07-2004, 10:23 PM
I'm sure that this subject has been broached before, but I can't for the life of me find it.

Genuine question here, not out to flame or war-monger, but in relation to the P-51's wings, is there a documented history for them to simply rip off so easily at speeds of about 700 kph (when pulling out of a dive, for instance)? More to the point, I suppose, is this phenomenon MORE COMMON in the P-51 than any other aircraft in WWII? I've never seen anything about this, but was wondering if this is something burried deep in the recesses of some archive.

I just figure if this was a common occurance...at least moreso than other AC, that it would have been better documented.

berg417448
12-07-2004, 10:30 PM
I doubt it was a common occurrence. It could happen to a number of planes. In fact I just recently read a combat report in which a Mustang chased an Me-109 and the 109 tried to dive away. After a high speed dive from 24,000 feet to about 10,000 feet both planes began a pullout. The 109 lost its right wing during the pull out and crashed. The Mustang pulled out just fine. I draw no conclusion from this...it is simply an event that happened.

Hunde_3.JG51
12-07-2004, 10:38 PM
Talked to a real Bf-109G-14A/S pilot last year (Hans Dulias), and he said against the P-51 their tactic was to dive straight down and pull out hard at very high speed as the P-51 would lose its wings if he tried to follow. I had to laugh because this was right about the time the debate about this was going on several months back. I'm not claiming anything as correct or not, but those were his words. Also remember superior elevator response of P-51 which can cause blackout easier and put alot of stress on wings at very high speeds.

CaptJodan
12-07-2004, 10:45 PM
So basically the culperate is the high elevator response, not necessarily that the wings themselves were weak, just that P-51's have such high stresses put on them with harsh pull outs that the wings couldn't take it.

I'm guessing the reason it must not have been mentioned often throughout other areas of history are that Stang pilots were taught not to pull such high G maneuvers, or that the high Gs simply prevented such maneuvers to be taken.

The Ki-84 seems to have pretty good response at those speeds during pullout. Did it have a stronger/better structure, or just less elevator response?

Cyrano
12-07-2004, 10:52 PM
One of the oddities of this game has always been why the creaters have arbitrarily decided to install "obscure" defects of certain planes and yet omit better known ones in other planes. IMO this is where a lot of people righly or wrongly start to believe certain nationalities/planes get porked or raised.

berg417448
12-07-2004, 10:54 PM
I also found this:


When the P-51D model became available in quantity in the summer (1944), cases of the
aircraft losing its tail surfaces in flight began to be reported. Flight
restrictions were placed on the aircraft and the tail surfaces were beefed
up. Wing failures were also reported due to control stick force reversal
in high-speed dives. The bobweight was added to the elevator control
system to fix this problem.

Hunde_3.JG51
12-07-2004, 11:07 PM
CaptJodan, elevator response is the main culprit in-game, but the P-51 did have problems with losing wings at high speeds in real life IIRC. I think others may be able to provide more information. I'm not sure about P-51 and Ki-84, but FW-190 had "through spar" construction in wings. This was a very heavy single spar that ran through both wing structures and across fuesalage (but not all the way through to end of wings), I wish I could scan and host as I have great pictures of this.

Fennec_P
12-07-2004, 11:21 PM
As with anything in the game, vague and contradictory/erroneous information available on the internet will continue to provide such conspiracy theories. Even with correct info, there is always the matter of degree to debate.

As such, it's hard to objectively comment on something like this. I can just hope that Oleg and crew are using good info and know-how to model the planes.

Cyrano
12-08-2004, 12:49 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Fennec_P:
As with anything in the game, vague and contradictory/erroneous information available on the internet will continue to provide such conspiracy theories. Even with correct info, there is always the matter of degree to debate.

As such, it's hard to objectively comment on something like this. I can just hope that Oleg and crew are using good info and know-how to model the planes. <HR></BLOCKQUOTE>


Agree 100%

Copperhead310th
12-08-2004, 01:04 AM
Ask Oleg ans see what he tells you about it.

he went into faily great detail in teaching me why this happens. needless to say it made my Jug look a lot more welcoming than the mustang.
But he explains it really well. seriuosly.

IL2-chuter
12-08-2004, 02:28 AM
My guess is the tail was the real reason Germans were diving away. The Germans themselves may only have known that Mustangs were crashing behind them. Early Mustangs, as noted above, had stabilizer problems and it wasn't until a few made it back with stabs barely hanging on that it was identified and fixed. The later wing failure problem was identified and fixed very quickly, as well as the engine mount hardware. I don't believe there were any structural issues as of late '44. We still don't have full fuselage fuel tank 2g stick reversal, nor do I expect it . . . just not possible in this game.

http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

VW-IceFire
12-08-2004, 08:50 AM
Oleg I think mentioned that it was a particular access hatch or a door or something on the wing that would, for whatever structural reason, come free during the stress of a dive...and that would rip the wing apart due to the loss of support.

I don't remember the details...only that its based on something they can model.

Lots of things this game cannot model. Pierre Closterman recounts a story told to him by a Spitfire XIV pilot...or rather a bit of a competition between XIV and Tempest V pilots. The XIV pilot bounced a Ar-234 (German jet bomber) and initiated what was probably close to 500 mph dive to get the target. He succesfully dispatched the Ar-234 but apon returning to base the ground crews found the XIV's airframe had been irreparably been warped. The aircraft was scrapped for parts.

So this may not make much impact in a dogfight server...but think about running a campaign with any fighter and you overstress it just a bit. The wear and tear is going to get you....or your plane is going to get thrown out. No doubt this was a component of the P-51's wing loss problems too.

Soulyss
12-08-2004, 09:36 AM
I think there are a couple issues with the P-51 design that may have led to failure in high speed dives. First the aft fuel tank, when it was more than say about half full it pushed the center of gravity too far aft. In high G manuvers the plane would be unstable and the pilot would actully have to push forward against the stick due to stick force reversals, if he was in a high speed pull -out and not ready for it I imagine the plane could try to swap ends and tear itself to pieces. Secondly the wing design of the P-51 allowed for higher speeds before the plane compressed. I think a combination of this is probably what led to most incidents of structural failure.

horseback
12-08-2004, 01:17 PM
The Mustang's fuselage tank was always drained first in flight, even before drop tanks, because of the CG problems encountered (and predicted by the North American design team) in the first few installed during familiarization flights over England. It quickly became part of 8th FC doctrine, particularly after some veteran pilots in fighter groups converting from the P-47 to the Pony were lost in this way. After the first few incidents, the fuselage tank was only filled when it was absolutely necessary to be able to reach an objective.

I've never heard of the tail problem, although there were some issues that led to the conversion from fabric to metal elevators. I doubt that those problems led to the loss of tail sections in any meaningful numbers.

As for the constuction of the wings, they actually went on the real aircraft in one piece--just like on a model airplane, and like most US fighter designs of the era, was overengineered, if anything. The Mustang was fragile only in comparison to the Thunderbolt or Warhawk, from an air to air perspective. The one bullet in the nose problem was more likely to encountered at low level from AA, than from an enemy aircraft the pilot was aware of.

As for wing loss, remember that US fighter doctrine called for making the enemy aircraft attempt to dive away from you. The standard German tactic throughout the war exploited their advantage over British, French, and Russian planes. The P-47, and then the Mustang came as an ugly shock. Every USAAF ace who fought in the ETO seems to have been quoted as saying that once they tried to dive away, the Axis fighters were easy meat. This suggests to me that most Mustangs were going to be dived steeply and pulled out hard multiple times, both in training (USAAF 'rat races' over the English countryside on non combat mission days led to numerous 'operational' losses) and in combat.

More than one had to have been overstressed without overt visible damage, and dived after a fleeing 109 or 190 one time too many. The surviving jagdeflieger, returning to his field alive, then condemned a few of his buddies to death by advising them that their bird was better than the Mustang in a dive, no ****.

1C seems to have converted a few anecdotal instances into an inherent design weakness for the Mustang's FM, while ignoring the glaring weaknesses of most Soviet early war fighters and the Il-2 itself (I've spent thousands of virtual flight hours shooting the hell out of Sturmovik oil coolers, and not once has it disabled the engine in less than 3 minutes, during which time the bastage enjoyed undiminished performance, bombing and strafing the bejesus out of the asset I was supposed to be defending). Don't even start me on the wartime performance of the late war Japanese fighters vs their RL operational experience, even with veteran pilots.

But I'm sure it has nothing to do with politics or prejudice...

cheers

horseback

TX-EcoDragon
12-08-2004, 01:18 PM
The wing failure is probably more to do with the available G that you can exert on the stick. This is based on the attempt by the sim designers to model such obscur things as control force to a sim where there really is no such thing. In addition Oleg had implemented a G dependant structural failure some time ago, and set it to around +15G in pretty much all planes! Some planes just cant reach that G loading, that doesnt make them stronger. In most sims people rip wings off all the time simply becasue unlike the real world they have no awareness of the G loadings imposed. Trust me your not going to sustain 8Gs for more than a few seconds if you've got a choice. . . though you might hit 10 rather easilly in a quick loading, you will still feel it. . . you'll really feel it. This doesnt really imply a structural weakness of one particular plane though. A 109 pilot (who could stand to hit the gym every now and then) that can't pull more than 5 or 6 Gs at, say 600 kmh will not be able to reach that 15G load where in the sim the P-51 pilot can simply because the lbs. of stick force per G of the p-51 is less than that of the 109. In the sim we simply move a joystick around, and most sim 109 pilots probably spend a lot of time with the elevator against the stop hoping to get some G out of the deal. P-51 pilots on the other hand have to feather the stick and be very carefeull as the stick is pulled that they are aware of the G they are pulling simply because they can pull more in that regime. . . if a 109 pilot hops in a pony, dives and pulls out chances are good the wings will be gone, or if not that, the pilot will blackout. In testing using things such as devicelink to give G load data this effect appears to be rather evenly spread across the flightline. I for one am glad to see that it was implemented, before it was not uncommon (and it still isn't, in truth) to see people pulling absurd G in some absurd maneuvers. In the pursuit of an accurate simulation these sorts of things are required. Now, I think there are many areas it can be improved, and clearly there are many aircraft in the sim that should fail sooner, they probably are not going to fail at 15G, probably at a lower value.

Keep in mind that most WWII pilots (or modern combat pilots for that matter) would rarely pull more than half of that 15 G loading. . . and when they do it is usually more or less the maximal amounts that they will ever pull.

Aaron_GT
12-08-2004, 02:09 PM
" In addition Oleg had implemented a G dependant structural failure some time ago, and set it to around +15G in pretty much all planes! Some planes just cant reach that G loading, that doesnt make them stronger."

Indeed Oleg has stated several times on the boards during earlier discussions on this sucbject that the 15G limit is the same (barring any bugs, I suppose) the same for all aircraft. The same for the blackouts. People had complained about the Mustang elevator effectiveness and he also stated that he would increase it but that people would find that they would blackout and possibly shed wings, much as people are experiencing. So it seems to come down to the elevator effectiveness.

Abbuzze
12-08-2004, 04:30 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Hunde_3.JG51:
I'm not sure about P-51 and Ki-84, but FW-190 had "through spar" construction in wings. This was a very heavy single spar that ran through both wing structures and across fuesalage (but not all the way through to end of wings), I wish I could scan and host as I have great pictures of this. <HR></BLOCKQUOTE>

You mean this or a similar photo? http://www.focke-wulf190.com/images/trennstellen.jpg

BuzzU
12-08-2004, 05:04 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Hunde_3.JG51:
Talked to a real Bf-109G-14A/S pilot last year (Hans Dulias), and he said against the P-51 their tactic was to dive straight down and pull out hard at very high speed as the P-51 would lose its wings if he tried to follow. I had to laugh because this was right about the time the debate about this was going on several months back. I'm not claiming anything as correct or not, but those were his words. Also remember superior elevator response of P-51 which can cause blackout easier and put alot of stress on wings at very high speeds. <HR></BLOCKQUOTE>

Wait a second! I thought the real 109 had a problem of it's elevator going stiff at high speed? The P-51 is known to have good elevator response at high speed. How was your pilot able to pull off something like this?

DangerForward
12-08-2004, 07:38 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by VW-IceFire:
Oleg I think mentioned that it was a particular access hatch or a door or something on the wing that would, for whatever structural reason, come free during the stress of a dive...and that would rip the wing apart due to the loss of support.
<HR></BLOCKQUOTE>

That was the wheel well door on the P51D, but that was fixed after the initial test flights of the P-51D. According to the Technical Services the losses due to structural failure were two per week for the 8th Air Force. This is according to "The Mighty Eighth War Manual".

VW-IceFire
12-08-2004, 08:18 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by DangerForward:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by VW-IceFire:
Oleg I think mentioned that it was a particular access hatch or a door or something on the wing that would, for whatever structural reason, come free during the stress of a dive...and that would rip the wing apart due to the loss of support.
<HR></BLOCKQUOTE>

That was the wheel well door on the P51D, but that was fixed after the initial test flights of the P-51D. According to the Technical Services the losses due to structural failure were two per week for the 8th Air Force. This is according to "The Mighty Eighth War Manual". <HR></BLOCKQUOTE>
Ahh...right on. Ok, I'm wrong here then http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Must just be the ability to reach 15+ G in a pullout.

Can we replicate that for some other planes with high elevator effectiveness? FW190? Ki-84?

TX-EcoDragon
12-08-2004, 08:47 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> IceFire said: Ahh...right on. Ok, I'm wrong here then http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Must just be the ability to reach 15+ G in a pullout.

Can we replicate that for some other planes with high elevator effectiveness? FW190? Ki-84? <HR></BLOCKQUOTE>

Yes, in fact using certain trim techniques (remember RBJ) you can observe this in most anything in the sim that can reach high enough speeds no matter what their elevator acts like. . .

Maple_Tiger
12-08-2004, 09:01 PM
Juast add some negative pitch-trim, there CaptJodan. It won't cure the issue, but it will help.

3.JG51_BigBear
12-08-2004, 11:36 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Hunde_3.JG51:
CaptJodan, elevator response is the main culprit in-game, but the P-51 did have problems with losing wings at high speeds in real life IIRC. I think others may be able to provide more information. I'm not sure about P-51 and Ki-84, but FW-190 had "through spar" construction in wings. This was a very heavy single spar that ran through both wing structures and across fuesalage (but not all the way through to end of wings), I wish I could scan and host as I have great pictures of this. <HR></BLOCKQUOTE>

The P-51 had two spars. One in the front and one running along the trailing edge of the wings for the flaps and ailerons to be mounted to. This second spar was necessary because of the extreme amount of pressure that was going to be placed on the P-51s flaps. The spars extended at least as far as the machine guns. All articles dealing with the construction and development of the P-51 make mention of the spars having to be placed far enought apart to accomidate the guns.

Unlike the through spar design on the FW190, each spar on the Mustang was a separate piece. For example, the front spar on the left wing was bolted to the center line of the aircraft and the front spar of the right wing was bolted to the center line, the two spars were not one continuous piece. I'm guessing this, coupled with the high elevator authoriry, coupled with the laminar flow wing (which I've always thought did more harm than good) and I think it makes sense that you'd be seeing these wing failures during such high speed/high G manuevers.

Saburo_0
12-09-2004, 12:22 AM
Some very informed explanations. Thank you!

IL2-chuter
12-09-2004, 01:50 AM
Without a G-suit and an upright seating postion, there is virtually no way to reach 15g's without blacking out first. If the G's are applied suddenly, a pilots resistance to the G's are reduced and blackout occurs earlier (lower G).

http://forums.ubi.com/images/smilies/16x16_smiley-indifferent.gif

Current 9g qualification is tortuous, requires a g-suit and the geforce* is applied smoothly.

*registered trademark, I think.

FA_Whisky
12-09-2004, 03:12 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> Without a G-suit and an upright seating postion, there is virtually no way to reach 15g's without blacking out first. If the G's are applied suddenly, a pilots resistance to the G's are reduced and blackout occurs earlier (lower G).



Current 9g qualification is tortuous, requires a g-suit and the geforce* is applied smoothly.
<HR></BLOCKQUOTE>

Thats why it is not possible to rip the wing off before you black out by just pulling out of a high speed dive. If +15g is the limit for the P51d it just should not be possible to do. But is the limit not +8g or +9g? Than, in theory you can lose a wing in a pullout.

Hunde_3.JG51
12-09-2004, 03:52 AM
Abuzze, yes something like that http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif. Though the photos I have are during construction and show how far the spar ran into wings.

BuzzU, I am just telling you exactly what he told me. I think the 109 could be pulled out of a dive just fine, it just took more effort both in strength and in workload. But he very clearly stated what he meant and that it was a tactic they used.

HellToupee
12-09-2004, 04:38 AM
ive ripped my wing off in a d9 plently of times

lbhskier37
12-09-2004, 05:41 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by IL2-chuter:
Without a G-suit and an upright seating postion, there is virtually no way to reach 15g's without blacking out first. If the G's are applied suddenly, a pilots resistance to the G's are reduced and blackout occurs earlier (lower G).

http://forums.ubi.com/images/smilies/16x16_smiley-indifferent.gif

Current 9g qualification is tortuous, requires a g-suit and the geforce* is applied smoothly.

*registered trademark, I think. <HR></BLOCKQUOTE>

The way blackouts work in IL2 though is that they fade in. This is why you can pull the wings off in IL2, in real life you never would be able to yank the stick and get 15+Gs, but in IL2 you don't feel the force and the blackout hasn't faded in yet so you can pull more than you could in real life. Oleg told us this would be the consiquence when all the Yank-whiners wanted even more elevator authority for their Pony.

CHDT
12-09-2004, 06:35 AM
Sorry for the 56k guys, but I think it's worth it http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

http://img127.exs.cx/img127/1724/Sanstitre-Numrisation-01.jpg

http://img127.exs.cx/img127/6784/Sanstitre-Numrisation-02.jpg

http://img127.exs.cx/img127/4227/Sanstitre-Numrisation-03.jpg

http://img127.exs.cx/img127/1865/Sanstitre-Numrisation-04.jpg

http://img127.exs.cx/img127/9092/Sanstitre-Numrisation-05.jpg

http://img127.exs.cx/img127/6464/Sanstitre-Numrisation-06.jpg

http://img127.exs.cx/img127/3167/Sanstitre-Numrisation-07.jpg

3.JG51_BigBear
12-09-2004, 08:13 AM
I wouldn't be able to understand this even if it was in English http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

FatBoyHK
12-09-2004, 09:32 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Cyrano:
One of the oddities of this game has always been why the creaters have arbitrarily decided to install "obscure" defects of certain planes and yet omit better known ones in other planes. IMO this is where a lot of people righly or wrongly start to believe certain nationalities/planes get porked or raised. <HR></BLOCKQUOTE>

to certain extent, I agree with you http://forums.ubi.com/groupee_common/emoticons/icon_razz.gif

BuzzU
12-09-2004, 09:59 AM
Speaking of G-suits and the P-51. Isn't the P-51 the only plane in the game that used a G-suit in real life? Shouldn't you black out less in the P-51 compared to the rest of the planes?

I've brought this up before, and was told that Oleg didn't model it. Hmmmm..all you need to do is give the P-51 less blackout. Is that hard? Do I think the LW guys would be screaming for this if the FW had used a G-suit? Yep!

Fennec_P
12-09-2004, 10:21 AM
With blackouts on, you can do unlimited amount of G for limited periods of time.

For example, In FB, I calculated 25G over 2 seconds in a FW-190 pullout, before blacking out. The fade-in is extremely forgiving. keep in mind, this is before load failures were modelled, so the wings stayed on.

So it is easy for many planes to do 15-20G if you accidentally pull to hard at high speed.

Also, 15G load limit is probably for static test or low speed. As airspeed increases, load limit decreases. Some planes have maximum of only 3-4 G at 700km/h, with maybe 1.5 safety factor. Which means, only 5-6 G will make the wings come off. No way a plane will have 15G load limit at 700km/h.

For example, flying Ki-84 at 750km/h. Just a few Gs, and wings come off. At 500km/h, you can yank and bank with impunity.

Same with P-51. Load failures only become possible at the very edge of maximum speed, like they should.

VFA-195 Snacky
12-09-2004, 10:51 AM
just learn the limitations of your plane and work within that.

ZG77_Nagual
12-09-2004, 11:15 AM
This was a pretty well documented problem with the mustang - to some degree throughout it's history.

FatBoyHK
12-09-2004, 01:51 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by BuzzU:
Speaking of G-suits and the P-51. Isn't the P-51 the only plane in the game that used a G-suit in real life? Shouldn't you black out less in the P-51 compared to the rest of the planes?

I've brought this up before, and was told that Oleg didn't model it. Hmmmm..all you need to do is give the P-51 less blackout. Is that hard? Do I think the LW guys would be screaming for this if the FW had used a G-suit? Yep! <HR></BLOCKQUOTE>

and I bet if VVS has G-Suit, I has already been implemented in the game...... since the original IL2!! haha

TX-EcoDragon
12-09-2004, 01:59 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by IL2-chuter:
Without a G-suit and an upright seating postion, there is virtually no way to reach 15g's without blacking out first. If the G's are applied suddenly, a pilots resistance to the G's are reduced and blackout occurs earlier (lower G)...
<HR></BLOCKQUOTE>

Actually it's the reverse. Blackout and GLOC happen after oxygen reserves in the brain are exhausted. This takes a few seconds, and during these first few seconds we can pull far more Gs than most aircraft can withstand. provided that the G onset rate is very high, and that the cessation of the force comes just as quickly before GLOC comes on. The aircraft structure, however, doesn't have such a time dependant buffer, and can sustain serious or catastrophic failure due to over G even though the pilot remained conscious, in fact in such events there will not be any visual artifacts beyond what we see at much lower G states. Given this it is quite possible to pull far more G than most aircraft can withstand provided that the g onset rate is fast, and that the force acts for only a short time. Many aerobatic aircraft are certified to 10 Gs, this is an operational value that has a nice large safety margin such that the aircraft should not sustain serious damage until 150% of that is reached. . . ie 15 Gs. Does this mean that a pilot can't break them without blacking out? Nope. . .they can. . . and have. In my flying I find that using a 10 G dive recovery has less visual/CNS effect on me than does a 6G recovery, simply because angular rotation is higher at higher G and thusly I can go from vertical dive to level in less time so the total time of the elevated G is less. (keep in mind that this only applies under certain circumstances when I am at low enough speeds to get from dive to level in a few seconds, most of the aircraft I fly this will be at ~ 180-190 KIAS or 333-350 kmh or less.)

Now the truth in your statement relates to the pilot's G tolerance being reduced by their physiological response lag time of a few seconds and perhaps their failure to perform anti G straining maneuvers in advance of the force application.


<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by lbhskier37:

The way blackouts work in IL2 though is that they fade in. This is why you can pull the wings off in IL2, in real life you never would be able to yank the stick and get 15+Gs, but in IL2 you don't feel the force and the blackout hasn't faded in yet so you can pull more than you could in real life. Oleg told us this would be the consiquence when all the Yank-whiners wanted even more elevator authority for their Pony. <HR></BLOCKQUOTE>

See previous reply. . . what you describe is in fact how it should be. . .

Here is a figure from the United States Naval Flight Surgeons Manual that depicts this:

http://www.txsquadron.com/uploaded/TX-EcoDragon/GLOC%20onset%20diagram.jpg

What you see here is that there are no G induced visual effects that the pilot is aware of for ~5 seconds no matter how high. It takes less than 5 seconds to remove a wing. Then you see that the visual artifacts of the G "fade in" with a peak efffect at 10 seconds after initial force onset, then the physiological responses (passive) factor in and increase tolerance somewhat.

Here is a more in depth summary of the physiological responses to the high G environment that will explain what is transpiring in the body as the forces act:

http://www.txsquadron.com/topic.asp?ARCHIVE=&TOPIC_ID=1498

CraytonRoberts
12-09-2004, 05:57 PM
Related to the question of G-forces, I've read contradictory information about the introduction of so- called G-suits. Were this, in a "primitive" form, introduced during WW2?

IL2-chuter
12-10-2004, 01:39 AM
Good points, EcoDragon. I recall AirForce (not to bring up service rivalry) research that found that there was only about 1.5 seconds of oxygen in the brain at any given moment. Sudden high G's were found to inhibit blood flow, maybe even stopping it in some cases, leading to blackout in as little as 1.5 to 2 seconds. Regardless . . . http://forums.ubi.com/images/smilies/16x16_smiley-indifferent.gif Your no doubt more correct than I. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif


I've found in my flying (RL) that anything over 4 G's gets my FULL and UNDIVIDED attention, and over loading is not a likely event in a familiar aircraft. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

Also, just because a spar is not one piece doesn't mean it's weaker (might even be stronger), it just means it's heavier.

Everyone, have a nice day.


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TX-EcoDragon
12-10-2004, 04:23 PM
So I see where this is going Chuter. . .your implying that the Navy has better fighter pilots aren't you!!!! :-D


As you said, pulling G's are not a transparent event to pilots, that's why the G suit requests for the P-51 will result in more trouble with wing shedding simply because there is no real indication of G loads other than the visual representation that the sim provides us with, and a well done G suit should reduce this effect a bit.

As far as my info goes, there is enough semi-contradictory info out there by valid sources to suggest that there isn't really that much known about this area of flight physiology. Mostly because it's tough to get volunteers for such tortures! So I'm not gonna say one is the be all end all right thing. . .I hope I didn't come off sounding like that. What I can say for certian though is that the diagram I posted seems about right for normal situations (including extreme aerobatics in under the term normal) in piston and from my understanding of flight physiology. For one thing, I am assuming a certain type of onset rate. . . ie one which is a realistic amount that a pilot can induce using normal means. . . now in supersonic flight perhaps it's reasonable that very high magnitude and extreme onset rates of G forces might be encountered in adverse situations (probably not pilot induced) or like those you might find after some sort of impact could have very different character than those that most piston pilots would encounter, or like those that I experience, which in the aircraft I'm flying are almost certainly capable of much higher g onset rates than most other piston engine aircraft. In my case I figure they are probably more on the order of about 15-20 G/Second at max with 10G as the maximal value I will usually hit, so I would expect that the above diagram would probably be appropriate to piston engine aircraft, as I don't thnk many aircraft out there will hit such rates.

I guess my .02 is adding to about $.50 . . . im known for being longwinded.