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BennyMoore
05-05-2004, 11:11 AM
Okay, we have spins. We've got lots of those. But, where are the stalls? I don't think I've ever once stalled my plane. I'm not talking about flying straight up until you lose your energy, like in a hammerhead. I'm talking about the thing that is a spin, only on both wings.

Now, as far as I know, a stall is a lot more common in real life than a spin. While I love the spins and feel that it adds a special difficulty to the game (and moreover, keeps it from being one of those brain-dead joystick-breaker games where everyone keeps their joysticks yanked back to the stops), I feel that realism should come first.

Is there some sort of explaination for the lack of stalls that I'm missing?

BennyMoore
05-05-2004, 11:11 AM
Okay, we have spins. We've got lots of those. But, where are the stalls? I don't think I've ever once stalled my plane. I'm not talking about flying straight up until you lose your energy, like in a hammerhead. I'm talking about the thing that is a spin, only on both wings.

Now, as far as I know, a stall is a lot more common in real life than a spin. While I love the spins and feel that it adds a special difficulty to the game (and moreover, keeps it from being one of those brain-dead joystick-breaker games where everyone keeps their joysticks yanked back to the stops), I feel that realism should come first.

Is there some sort of explaination for the lack of stalls that I'm missing?

TgD Thunderbolt56
05-05-2004, 11:53 AM
In this game, stall = spin (in most planes)

Accurate or not.



http://home.earthlink.net/~aclzkim1/sitebuildercontent/sitebuilderpictures/il2sig2.jpg

EFG_Zeb
05-05-2004, 12:01 PM
All spins start with a stall...A spin is a stall that the pilot let decay into a spin. Most of the time if you make a prompt recovery you will avoid the spin and just have a stall...

"See, Decide, Attack, Reverse or Coffee Break" E.H.

MA_Moby
05-06-2004, 09:19 AM
^^^^^ Like they say, the way to avoid a spin is to avoid a stall. Most of the planes in FB are almost guaranteed to drop a wing in a stall, and unless you catch it they'll spin. So stalls must happen in FB, otherwise spins wouldn't http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

LeadSpitter_
05-06-2004, 09:53 AM
I liked FB 1.0 and il2sturmovik when it took a couple hundred meters to actually recover. Now they just dont happen a simple centering of the stick you out of it

The aircraft that can stall instantly if wanted look like cfs2 flipping stalls it looks to silly.

Its rare to see an unrecoverable stall or flat spin unless control surfaces are damaged.

Oleg needs to stop listening to the arcaders who thought the b17 was to tough using no valid tactics to bring one down. Now 3-4 pop like airballoons in level one pass front attack or rear attack no skill what so ever to take them down anymore. Before you had to bnz at top speed now anything works easily.

1 il2 and bf110 are more trouble then 16 b17s

http://img14.photobucket.com/albums/v43/leadspitter/newsig.jpg

Chuck_Older
05-06-2004, 10:35 AM
OOo, I dunno about that, L_S, I had an unrecoverable spin in a P-51 last week. I tried to get out of it for almost 3000 feet (praticising aerobatics http://ubbxforums.ubi.com/images/smiley/16x16_smiley-happy.gif ). I cut power, opposite rudder, stick forward...nothing. Full power, neutral stick, opposite rudder, nothing. Dropped flaps, dropped gear, couldn't slow down. At 400 kph and 1500 feet, I got the heck out of the plane.



But, yes, stalls seem odd. This has been brought up and noted before, but since it's still an issue, no harm in mentioning it again

*****************************
The hillsides ring with, "Free the People",
Or can I hear the echoes from the days of '39?
~ Clash

p1ngu666
05-06-2004, 11:26 AM
use full flap and power, opposite rudder http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif
u often get too a point where plane is \ angle and just goes round and round tho :\

http://www.pingu666.modded.me.uk/mysig3.jpg
<123_GWood_JG123> NO SPAM!

Seafire_LIII
05-07-2004, 01:59 PM
It seems to me that nearly every stall (high speed or low speed) in IL-2 FB AEP is followed by a spin and if that's not the case then a snap half roll!
Also you need a lot of altitude to get out of a spin- the NACA spin-recovery procedure just doesn't work very well!

Aaron_GT
05-07-2004, 02:50 PM
"Its rare to see an unrecoverable stall or flat spin unless control surfaces are damaged."

I've had them lately in the P63, P51, Spit, and
P38. I am not sure if there was any damage in
these cases. They do seem a lot harder to get
into that the original IL2. Maybe my skills have
improved (I don't have the original IL2 on my
PC to compare with) but I think the stalls have
got much more gentle. The Mig 3 used to stall
and flip violently in the original Il2, and
the P39 could be a death trap.

It seems a lot of game details are subjective,
though. I see people saying the P63 is tough
and the P47 fragile, and apart from the P47
fuel leaks I find that online the P47 is tough
and the P63 lights up like a candle soon as
look at it! Weird...

WWMaxGunz
05-07-2004, 04:51 PM
There was a VERY GOOD active thread on just this issue over in General Discussion at least a month ago. Great posts by many pilots with many hours, even a couple of, possibly more, aerobatics pilots and at least one as a member of an active competitive aerobatics team. Answer from many if not all: yes the overall model spins too easily. Other words: it's not all that important in a combat flight sim. But you can't ride a stll without a wing dropping right now. That thread has some very, very good in depth aero knowledge although in places it reads like a brick.

Any bets as to this being one of the changes in the delayed from original expectations patch?


Neal

BennyMoore
05-08-2004, 07:54 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by EFG_Zeb:
All spins start with a stall...A spin is a stall that the pilot let decay into a spin. Most of the time if you make a prompt recovery you will avoid the spin and just have a stall...<HR></BLOCKQUOTE>

Yes, but in real life, you can choose to not make a prompt recovery from a stall, and the stall still won't turn into a spin unless certain factors make only one of the wings stall. A stall doesn't degrade into a spin naturally; in fact, the reverse is more likely, because in a spin you still have lift on one wing to lose. In a stall, you can't lose lift because it's already lost, and you can't exactly recover just one wing.

You seem to think that a spin is the natural progression of a stall. It is not. I feel that Wwmaxgunz is right and that it is too easy to spin in IL-2, and not possible to simply stall (not counting the microsecond stall that preceeds all spins in this game).

If you have played Lock On, you will know what a stall is. Your nose simply drops, and will continue to do so until you release the controls and until the aircraft gains sufficient airspeed. Note that this is not the same situation as flying at a high angle of attack until your aircraft loses airspeed. They are different kinds of stalls, I think; is one of them an accelerated stall, perhaps the one resulting from pulling the stick back too hard? If so, what is the one called that is caused by losing airspeed?

05-09-2004, 02:36 AM
That's because you don't know what a "stall" really is. When you choose not to recover from a stall a plane automatically recovers itself.

"Stall" is a condition defined as a state where a plane cannot maintain current status in altitude, at a decent rate of zero. Whether it is induced by low speed(which, makes insufficient lift to hold the plane up) or by irregular AoA, a state of a "stall" is when the plane cannot keep its nose up any longer.

So, what happens if you choose not to recover from a stall? Obviously it involves leaving all controls at neutral.

Like you said, a stall doesn't necessarily develop into a spin when the conditions don't call for it.

A spin develops when one wing stalls before the other, and the end result along with irregular AoA, brings imbalance in airflow and thus, the flow of air is effectively "peeled off" from the wing.

Therefore, a stall which does not have any tendency to develop into a spin, typically only occurs when the plane maintains 0 bank angle.

For instance, a plane is climbing at a steep angle of 60 degrees with 0 bank, flying straight forward. Now when the air speed reaches the stall speed what happens? You can't keep your nose up any longer. That's a stall. A "stall" isn't some exotic wild condition of no control at all.

So, what happens when you let go of the plane's controls at that moment? The plane noses down, regains speed and then voila - the stall is over.

Or, imagine when you are flying straight and level. You cut the throttle, and use the control column to maintain current altitude despite of the lack of power. Soon, your plane will not be able to keep current altitude due to loss of lift. That's a stall. You let your hands go, and the plane will nose down, regain speed, and return you the control.

Now, during turns, where a plane is given a bank angle, the lift beneath the two wings is unequal(which, creates a horizontal and vertical component of lift, which in turn makes the plane turn).

A spin happens when during turning the pilot goes over the limits of regular AoA. The airflow is ruptured and what happens next is the plane is engulfed in a state of uncertainty. The balance between different lift components and various forces(such as torque, propwash, gyro effect and etc etc..) is broken, and whichever force is dominant at that moment kicks in without counterbalance - therefore, the plane, while in a state of stall, begins to spin in the direction where the dominant force is applied. It could start spinning in the yaw axis, or the roll axis(rarely in the pitch axis though..), or both.

So, is it possible for the plane to just 'stall' and not 'spin' while turning in FB/AEP?

Yes, it is possible. It's just that nobody realizes that they're doing it all the time.

If the plane is able to maintain a penalizing turn rate in speed, but still remain within the limits of AoA, then the plane will evidently stall out due to loss of speed, even when the max AoA is not reached. You can't turn at the same alt anymore in that condition.

What usually happens is such state is rarely recognizable at all, because people don't come to that in the first place almost instinctively.

Nobody turns at a set altitude while actual combat. The plane slowly loses altitude while turning in most cases - most people turn their planes in this manner. This is because instinctively people try to keep a certain air speed.

What happens if the pilot really keeps a tight turning radius, and keeps a close eye on the altimeter so the altitude does not drop at all? Well, if the turning radius is tight enough to constantly kill speed, the plane will stall as you'd expect. It's start buffeting, and then slowly want to point the nose downwards. If you deny that, the turn is halted at some point. That's a stall.

The confusion behind all this is that in the game, the "STALL!" hud text shows itself when the plane already passed the stall phase, and has entered a spin phase - in reality, the plane was under the stalling status all along, and people just don't realize it.

Aaron_GT
05-09-2004, 03:35 AM
"That's because you don't know what a "stall" really is. When you choose not to recover from a stall a plane automatically recovers itself. "

A few planes can get into a flat stall, though,
if their COG and COL are coincident.

Some planes will tend to drop a wing in a stall,
though, and the same wing each time, due to prop
wash AFAIK.

WWMaxGunz
05-09-2004, 05:37 AM
I can only Highly Reccomend reading that thread in the GD forum even if it means searching. Some of those guys get very technical in good ways.

Kweassa I agree that most people playing the sim don't know when they've begun stalls. I see that every time I see yet another whine post about turns in such and suc a plane when my own experience with the same plane in the same sim is much better. Someone didn't know when to stop pulling on the stick let alone how to ride the thing as the plane slowed down. But honestly the really good ones in that GD forum thread do know their stuff and rightly point out about wing drop, just as rightly say it's not that big of a deal in a combat flight sim. http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif More of a small peeve like when you had to hold side stick to stay in a bank, which got fixed/changed.


Neal

BennyMoore
05-09-2004, 12:23 PM
There's one other kind of stall, though. It can happen even when your airspeed is well above the stall speed and when you have zero angle of attack. It happens when you jerk back on the stick too suddenly on aircraft with excessively large control surfaces (which describes just about all World War Two fighters). The airflow over the wing is disrupted into some sort of vortex (I think; I'm not very sure about any of this), pushing the wing down. If you are straight and level when this happens, this should happen to both wings.

However, this situation only happens to one wing in IL-2. If you are going straight and level at a normal speed in the game, and you jerk back on the stick, your plane will instantly spin instead of instantly stall. Note that I'm not talking about pulling back on the stick until your angle of attack is too great or your airspeed too low. I'm talking about pulling the stick back to the stops, putting the elevator near a ninety degree angle from the wing (although not quite).

Again, I think that there are terms (stall, accelerated stall) for the two different kinds of stalls that we're talking about, but I'm not sure which is which. It makes sense to me that the condition that I am describing would be the accelerated stall, but things don't always make sense.

05-09-2004, 02:33 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>There's one other kind of stall, though. It can happen even when your airspeed is well above the stall speed and when you have zero angle of attack. It happens when you jerk back on the stick too suddenly on aircraft with excessively large control surfaces (which describes just about all World War Two fighters).<HR></BLOCKQUOTE>

No, Benny, that's not "0 Angle of Attack". That's "0 bank angle". When you jerk back on the stick the AoA increases to fast for the plane to cope with.


<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> The airflow over the wing is disrupted into some sort of vortex (I think; I'm not very sure about any of this), pushing the wing down. If you are straight and level when this happens, this should happen to both wings.<HR></BLOCKQUOTE>

No, it doesn't happen that way.

A plane does not fly in a theoretically perfect condtion where all four major forces are equally balanced out. Every moment during the flight there are always minor changes in lift force which is applied assymetrically to all axises. It's just that when the main flow of air is constant, the plane can continuously correct itself from such tendencies and fly "straight and level".


<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> However, this situation only happens to one wing in IL-2. If you are going straight and level at a normal speed in the game, and you jerk back on the stick, your plane will instantly spin instead of instantly stall.<HR></BLOCKQUOTE>

That's because once accelerated stall happens, the most dominant force at that moment will begin to influence the plane more than anything else - and that usually tends to be torque. What you're saying is that when a 0 banked plane suddenly pulls back the plane should just stall and then its nose should come down - things don't happen that way. As soon as such accelerated stall happens the torque will be the largest constant factor, since the airflow is disrupted. The plane will violently roll out in the direction designated by the torque force(this is what we call a 'snaproll').

To make it short, the violent nature of the jerking pull is what makes "accelerates" the stall. The plane go wild, and as pilots say "once you lose airflow over a wing, anything can happen".

If you're suggesting that a sudden max deflection of the stick would still cause a casual, slow approaching stall, and then spin out - then you're wrong.


<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> Note that I'm not talking about pulling back on the stick until your angle of attack is too great or your airspeed too low. I'm talking about pulling the stick back to the stops, putting the elevator near a ninety degree angle from the wing (although not quite).<HR></BLOCKQUOTE>

You're confusing the terms again. Check it over again. The AoA increases with stick pull. I think you may be confusing it with pitch angle or something.


<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Again, I think that there are terms (stall, accelerated stall) for the two different kinds of stalls that we're talking about, but I'm not sure which is which.<HR></BLOCKQUOTE>

Both are essentially the same. A stall is a stall. How a plane stalls, is what is different in each case. An "accelerated stall" is not a parallel term existing side by side with "stall" - ie) as in "orange" and "apple". It's a term subject to the wider category of "stall" itself - ie) as in "fruit" - "apple".


<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>It makes sense to me that the condition that I am describing would be the accelerated stall, but things don't always make sense.<HR></BLOCKQUOTE>

Yes, it is an accelerated stall. It is a stalling condition caused when the plane is still above the stall speed - but the normal airflow has been fatally disrupted due to excessive AoA produced by sudden/gradual pilot input which goes over the physical limits of the plane.

And an accelerated stall is highly likely to develop immediately into a spin - because, as said before, once the normal airflow dies out, the enormous propwash and torque force caused by a 2000hp engines will assum total domination over all other forces working on the plane.

ps) In fact, the torque forces are already too weak in FB/AEP planes. It's incredibly easy to go up into a vertical zoom straight 90degrees up - whereas in real life the slower the speed gets the torque force will try to throw the plane off into one direction all along the zoom, where the pilot has to constantly work rudder, aileron, and elevator to execute a perfect tail-slide or a hammerhead.

ps2) Which, the ease of such maneuvering, is the main cause behind people sniping a vertically zooming plane from some 500m away.. but that's another story.

LeadSpitter_
05-09-2004, 02:42 PM
Chuck_Older the key is dont fight the stall just center stick and your instantly out of it.

the only stall you need to fight is a flat spin but as soon as you start flipping around the center stick move will get you out of it immediatly

http://img14.photobucket.com/albums/v43/leadspitter/newsig.jpg

WWMaxGunz
05-09-2004, 02:49 PM
AOA = Angle Of Attack is the angle that your wings cut into the air with relation to your flight path.

Whenever your wings exceed the critical AOA for your plane (which varies with conditions like alt and power if I understand correctly that power on stall is higher than power off also gear/flaps up/down, but not speed if I also understand correctly) then you stall and your lift to drag ratio drops like crazy --- most people just say you lose lift but if you have the power and control then you can keep on flying.

Jerking the stick back will get your wings to change angle much faster than you flight path and you stall. Trying to turn or loop or whatever pitch maneuver harder than the plane itself can closely follow will stall you. Trying to fly too slow and you need to raise the nose but your flight path doesn't... you stall in the best known way but they are all the same root cause.

There are people here who can give you critical AOA's of different planes and name the conditions affecting them.


Neal

BennyMoore
05-10-2004, 04:20 AM
We're talking two different languages. I wish I had the Cessna video to clarify.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Kweassa1:
When you jerk back on the stick the AoA increases to fast for the plane to cope with.<HR></BLOCKQUOTE>

In the condition that I am describing, the stall occurs from airflow disruption around the control surface. Lift is lost although the plane is flying straight and level, and the wings drop before the nose raises at all.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Kweassa1:
If you're suggesting that a sudden max deflection of the stick would still cause a casual, slow approaching stall, and then spin out - then you're wrong.<HR></BLOCKQUOTE>

Again, you completely misunderstand me - although that is perhaps my fault. Anyway, what I am suggesting should happen is that a sudden max raising of the elevator should instantly cause the nose to drop, without ever starting to rise as it would if you pulled the stick back a little bit.

You know the way one wing drops when you pull back all the way in IL-2, even if the nose doesn't rise? I'm thinking that it should happen to both wings, at least some of the time.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Kweassa1:
You're confusing the terms again. Check it over again. The AoA increases with stick pull. I think you may be confusing it with pitch angle or something.<HR></BLOCKQUOTE>

I believe you are right. I've been using "angle of attack" to describe pitch angle. Doh!

You know, that last part about torque does throw a completely different light on it.