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raaaid
02-12-2006, 06:21 AM
when the plane stalls the flow of the wind on the the wings becomes turbulent and the dinamic sustentation decreases and the plane spins to the left oposite to the propeller just as in 4.01 happened

my question is why in 4.02 and in 4.03 when stalling the plane spins to the right

in 4.01 i wouldnt have to touch the alerons to roll i would do it with the engine torque but in 4.02 and in4.03 the spin is akward

Chuck_Older
02-12-2006, 07:13 AM
What planes are you flying that you can't torque roll now?

The only thing I can add about the stall is that a spin is actually a stall in which one wing stalls before the other, and it's not really turbulent airflow, per se, that causes the stall, it's that the flow of air over and under the wing can no longer generate lift. I suppose the airflow around the stalled wing could be described as turbulent though. Certain aircraft have devices called "spoilers" on the wings, designed to disrupt (literally spoil) the airflow, reducing lift- but they aren't designed to make the plane stall

raaaid
02-12-2006, 08:02 AM
i cant torque roll the k4 for example

in my opinion and it was like that in 4.01 any lack of sustentation due to low speed or to stall would mean torque on the plane and always in the same sense

you can do this experiment:

in 4.01 take a k4 flying straight at full throtle pull the stick all of the way, the plane will always roll left but if you try it in 4.02 and 4.03 it will always roll right

thats why since 4.02 i cant torque roll the plane as i want and i cant see explanation for this change in the fm

Chuck_Older
02-12-2006, 08:03 AM
Hmmm...maybe this has to do with an attempt to get rid of the wobbling issue so many people had?

SeaFireLIV
02-12-2006, 10:11 AM
Yep. i think a lot of the `wobble` problems with people was Oleg`s attempt at adding realistic torque effects in flight. As far as i can tell, Oleg has neutered torque to try and stop the `problem` if it is a problem about `wobble`.

I personally feel we have lost some aircraft flight realism due to this.

Freelancer-1
02-12-2006, 11:17 AM
I don't see any evidence of planes stalling. Period.

In this game all they do is spin. I have yet to see evidence of proper stall behaviour that can be recovered from by normal, real life, recovery techniques.

The planes will always drop a wing and spin.

This is not how it is in the real world.

AFSG_Bulldog
02-12-2006, 11:40 AM
First off... What type of stall are you trying to perform? Approach to landing stall, departure stall, accelerated stall etc. Each stall has its own peculiarities. The left or right turning tendencies is not just determined by torque. You have to consider things like "P" factor, prevailing winds and control surface position as well.

Each of those factors will (or could) produce varying stall characteristics. For example, if you were to attempt a hammerhead stall and at the top of the maneuver you kick in left rudder. You also have to apply right aieleron. The right wing is going faster than the left and is producing more lift. In real life, if you do not add the right aieleron the plane should fall on its back in stead of scribing a nice piorette around the left wing tip.

But this is just a game and it is impossible to address each and avery variable pertinent to the physics of flight and code them into a game.

I just ease the stick pressure when I get the buffet and rarely ever stall (except for the hammerhead maneuver).

Now why does it appear as it is different between the patches, I don't know. I have not really noticed the difference.

Viper_42
02-12-2006, 11:47 AM
Originally posted by Freelancer-1:
I don't see any evidence of planes stalling. Period.

In this game all they do is spin. I have yet to see evidence of proper stall behaviour that can be recovered from by normal, real life, recovery techniques.

The planes will always drop a wing and spin.

This is not how it is in the real world.

I've always thought the stalls in the game weren't realistic as well.

How would they stall in RL?

Chuck_Older
02-12-2006, 12:22 PM
Originally posted by Freelancer-1:
I don't see any evidence of planes stalling. Period.

In this game all they do is spin. I have yet to see evidence of proper stall behaviour that can be recovered from by normal, real life, recovery techniques.

The planes will always drop a wing and spin.

This is not how it is in the real world.

http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif Well, firstly, in the real world, a spin is a stall

Secondly, this is old, old news. When the sim's engines were made, the goal was to model aggravated stall conditions over 'normal' stall. Good or bad, a decision was made about doing it this way...and we've been dissecting it ever since. It's an old sim at it's core. It's got a new coat of paint, and many new features, and new aircraft, and some pretty good FMs here and there if we look, but the truth behind it all is that the sim has been stretched past it's performance envelope. Some stuff is going to be wrong http://forums.ubi.com/groupee_common/emoticons/icon_frown.gif

Freelancer-1
02-12-2006, 02:22 PM
Originally posted by Chuck_Older:



http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif Well, firstly, in the real world, a spin is a stall

http://forums.ubi.com/groupee_common/emoticons/icon_frown.gif

Not exactly true, Chuck. A spin is ONE wing stalled, and the two wings are operating at different angles of attack. In a standard stall (the way everyone but you, apparently, thinks when they hear the word), BOTH wings stop generating lift at the same angle of attack.

Most pilots, don't break a sweat in a stall as recovery is so basic. Althought I don't know specifcally about WW2 birds, I know that there are plenty of high performance prop planes in which as long as you can waggle the rudder, you can ride a stall wings level until you hit the ground. Can't say I've heard of that happening in the game.

Cheers,

Chuck_Older
02-12-2006, 03:03 PM
http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif A Spin is a type of stall...you just posted that, quote

"I don't see any evidence of planes stalling. Period.

In this game all they do is spin."

Now in your reply, you tell me that you know a spin is a stall.

Great http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif now we're getting somewhere. But if you knew that already, why'd you post that you didn't see any evidence of a stall. Period.

This is supposed to get under my skin, I think:

"the way everyone but you, apparently, thinks when they hear the word"

Well, I'm not the only one that thinks this way...the professors at my University thought that way, and taught it that way...if one wing stalls....you have encountered a stall. Pretty basic, I think. AFSG Bulldog addresses this point a bit...read his post

Don't know why you want the personal approach with me, but that's your affair. Everyone takes their stab, it seems, I don't take offense usually, it's hard to tell what people mean by reading a post online sometimes

TX-EcoDragon
02-12-2006, 04:11 PM
Originally posted by Freelancer-1:
I don't see any evidence of planes stalling. Period.

In this game all they do is spin. I have yet to see evidence of proper stall behaviour that can be recovered from by normal, real life, recovery techniques.

The planes will always drop a wing and spin.

This is not how it is in the real world.

I would have agreed with you before, but in 4.xx rudder work can prevent a spin when in a sustained stall. Some planes do this better than others, but "falling leaf" type stalls are possible now, and most fighters don't do these well at all in the real world.

TX-EcoDragon
02-12-2006, 04:19 PM
Originally posted by raaaid:
when the plane stalls the flow of the wind on the the wings becomes turbulent and the dinamic sustentation decreases and the plane spins to the left oposite to the propeller just as in 4.01 happened

my question is why in 4.02 and in 4.03 when stalling the plane spins to the right



I'm assuming you are performing accelerated, uncoordinated stalls, and are yawing to the right as a result of the gyroscopic effects of the prop which is acting to a greater extent than torque effects are. The trouble with the FM is that in the real world, at the critical angle of attack, as the wing starts to stall, the pitch change pauses and gyroscopic precession does as well, but torque doesn't, and this leads to a rolling moment. The sim seems to not have much rolling moment and the gyro effects win this battle. During a 1G stall you will be less likely to see this as the pitch rate is less and there is next to no gyroscopic precession.

Freelancer-1
02-12-2006, 05:33 PM
Originally posted by TX-EcoDragon:

I would have agreed with you before, but in 4.xx rudder work can prevent a spin when in a sustained stall. Some planes do this better than others, but "falling leaf" type stalls are possible now, and most fighters don't do these well at all in the real world.

Interesting, and might I say, good newshttp://forums.ubi.com/images/smilies/25.gif

I definitely look forward to checking this out.

Thanks for the info.

Z4K
02-13-2006, 04:32 AM
Originally posted by Chuck_Older:

...and it's not really turbulent airflow, per se, that causes the stall, it's that the flow of air over and under the wing can no longer generate lift.

I totally agree with the point about turbulent airflow. Lots of people get "transition" (from laminar to turbulent) and "separation" (from attached to detached flow) mixed up.

The airfoil does continue to generate lift at and after the stall though. The stall's just the point at which increasing the AoA no longer increases the coefficient of lift (Cl). It is associated with a sharp increase in drag. After the stall, one does often still have a high Cl.

It's been observed (including by the Wrights in their wind tunnels) that many airfoils have a second 'peak' in Cl at AoAs above the stall. In some cases the value is significantly higher than the first, though using it is (conventionally) impractical, because of the high drag at those higher AoAs. It is a consideration with modern fighters performing very high AoA "super-maneuvers"




Originally posted by Chuck_Older:

http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif Well, firstly, in the real world, a spin is a stall


I see "spin" the same way -- as a stall of one wing. I can see how "stall" typically means "both wings" to most people, as that's how it's usually used. Stalls and spins are seen as discrete events.

bogusheadbox
02-13-2006, 06:46 AM
Originally posted by AFSG_Bulldog:
if you were to attempt a hammerhead stall and at the top of the maneuver you kick in left rudder. You also have to apply right aieleron. The right wing is going faster than the left and is producing more lift. In real life, if you do not add the right aieleron the plane should fall on its back in stead of scribing a nice piorette around the left wing tip.



I may be wrong, but i don't recall using any airleron input when I and my instrctor made those manouvers. Funnily enough it was in a bulldog.

Maybe it depends on the speed of forward motion and the thrust generated through different aircraft.

For my instance it was paramount to keep the aircraft verticle (not looking forward but constantly over left / right shoulder) before imput of full rudder.

At time of manouver our forward speed was so little, it was mainly the airflow of the propellor over the tail that made the plane spin on its wingtip. I am sure i didn't use any airleron.

Maybe it would not be same with other aircraft with different power to weight ratios that would require more forward momentum to perform the manouver.

Maybe my instructor applied a little airleron as we rolled (i was focues at the time on keeping our verticle position). But i didn't notice any force applied on the stick.

I will have to enquire...

raaaid
02-14-2006, 06:47 AM
now i know whats wrong since 4.02, just there isnt torque when stalling

you can confirm it with this experiment:

take a k4 level at 500 km/h and stall it with full throtle on by pulling the joystick

then repeat the proces but at 0 throtle

it behaves exactly the same when stalling, 600 horse power of torque has the same effect than 0

no wonder why since 4.02 i cant roll the plane torque asisted just there isnt torque anymore when stalling

this is a big mistake and i hope somebody supports me so this can be fixed in the future

WB_Outlaw
02-14-2006, 02:44 PM
raaaid, although I think you have the concept, a better definition of a stall is the following...

Stall occurs when the angle of attack, which is NOT the pitch angle btw, reaches the point that the airflow "seperates" from the leading edge of the wing and instead of flowing over the upper surface of the wing it moves away from the surface. The actual direction, (up, down, left, right, x, y, z , radial, tangential, etc) depends on the attitude of the airfoil and the coordinate system in use.

This may not be 100.000000% correct but engine torque itself does not cause spins as it causes a rolling moment only. However, this rolling moment can induce other moments as the dynamics of the aircraft are changed due to the stall which will increase the tendency to spin. The most notable effects are gyroscopic precession and the p-factor caused by the airflow coming off the prop.

I'm going to test the no torque possibility later tonight. If I can confirm it I'll post a track of various aircraft.


--Outlaw.

TX-EcoDragon
02-14-2006, 04:56 PM
Originally posted by bogusheadbox:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by AFSG_Bulldog:
if you were to attempt a hammerhead stall and at the top of the maneuver you kick in left rudder. You also have to apply right aieleron. The right wing is going faster than the left and is producing more lift. In real life, if you do not add the right aieleron the plane should fall on its back in stead of scribing a nice piorette around the left wing tip.



I may be wrong, but i don't recall using any airleron input when I and my instrctor made those manouvers. Funnily enough it was in a bulldog.

Maybe it depends on the speed of forward motion and the thrust generated through different aircraft.

For my instance it was paramount to keep the aircraft verticle (not looking forward but constantly over left / right shoulder) before imput of full rudder.

At time of manouver our forward speed was so little, it was mainly the airflow of the propellor over the tail that made the plane spin on its wingtip. I am sure i didn't use any airleron.

Maybe it would not be same with other aircraft with different power to weight ratios that would require more forward momentum to perform the manouver.

Maybe my instructor applied a little airleron as we rolled (i was focues at the time on keeping our verticle position). But i didn't notice any force applied on the stick.

I will have to enquire... </div></BLOCKQUOTE>

It is absolutely critical to apply opposite aileron in the kick of the hammerhead, in addition to forward stick for a left pivot with a CW engine rotation.

WB_Outlaw
02-14-2006, 09:52 PM
raaaid is right about the 109's stall behavior. At low and medium speeds (I didn't try anything over 425 kph) both power on and power off, a smooth and fairly quick pull back from neutral to full force results in an expected pitch up until the stall which will, of course, vary depending on the initial speed at which the maneuver begins. At the stall there is a slow roll to the right and the nose drops. The roll continues to the right throughout the stall as the aircraft spirals down nose low. A spin does not develop. Releasing the stick results in a quick although not always instant recovery. Note that if you apply ANY OTHER STICK OR RUDDER input the stall will almost immediately develop into a very hard flat spin (or at least as close as the game can come).

Doing the same pull back to full deflection (applied force) in a P-51D results in a near immediate spin.

I believe this is an attempt to model the fairly docile stall characteristics of the 109 in that (according to the reports I've read) it "mushed" long before it uncorked and spun and is most likely the best compromise given the limitations of the flight model. It is puzzling as to why the roll would be to the right though.

--Outlaw.

darkhorizon11
02-14-2006, 11:45 PM
The airplane can spin with or against the rotation of the propellor depending upon the aircraft and whether or not it is slipping or skidding...

Explaining why is way to complex for me to write out. I'm not saying your to dumb to understand, its just that I'd have to explain a dozen other principals first. I'd take wayyyyy to long.

raaaid
02-15-2006, 02:38 AM
yes but my opinion that theres no torque while elevator asisted stall is just for 4.02 and 4.03, 4.01 was perfect and you could torque roll without the ailerons

then was it wrong in 4.01?

WB_Outlaw
02-15-2006, 10:33 AM
raaaid, describe the torque roll maneuver you are talking about. None of the aircraft modeled in this game should be able to do a true torque roll and even if they could, I don't think any version of the flight model could correctly model it.

--Outlaw.

raaaid
02-15-2006, 12:02 PM
in 4.01 dogfighting with the 109 i wouldnt use the ailerons to save all energy for the elevators, of course i could only roll left, i would roll by stalling the plane with the elevator, the more i stalled it the more it rolled

WB_Outlaw
02-15-2006, 12:28 PM
Originally posted by raaaid:
in 4.01 dogfighting with the 109 i wouldnt use the ailerons to save all energy for the elevators, of course i could only roll left, i would roll by stalling the plane with the elevator, the more i stalled it the more it rolled

The closest real maneuver to what you are describing is a snap roll, not a torque roll. A torque roll requires a T/W ratio > 1 and is a roll induced by engine torque with the aircraft hanging vertically from the prop, preferably at insanely low altitude.

In the absence of any other stick inputs the aircraft most likely should roll to the left under the conditions you are describing and I tested, however, as I said before, I don't think it's a bug, I think it's a compromise. Maybe I'm wrong and it will be changed in the future. If you think it's a bug, make a track and send it to the bug reporting e-mail.

--Outlaw.