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tonywizzz
04-04-2004, 04:33 PM
I am trying to advance my flying, this is where my main difficulty lies, what are the condtions where this occurs, presumably it is mainly related to speed and angle of banking,

1) Explanations pls?
2) Can you feel it happening?
3) How can you attempt to correct?

Some explanations of how other in-flight "phenononem" would also be appreciated, head shake, gyro, flutter etc.

Not got to complex engine managment yet, so eave that for now, I need to master flight characteristics first!

Use the Spitfire for example. this is the aircraft I want to fly "properly" (In the absence of Mosquito).

Tks

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tonywizzz
04-04-2004, 04:33 PM
I am trying to advance my flying, this is where my main difficulty lies, what are the condtions where this occurs, presumably it is mainly related to speed and angle of banking,

1) Explanations pls?
2) Can you feel it happening?
3) How can you attempt to correct?

Some explanations of how other in-flight "phenononem" would also be appreciated, head shake, gyro, flutter etc.

Not got to complex engine managment yet, so eave that for now, I need to master flight characteristics first!

Use the Spitfire for example. this is the aircraft I want to fly "properly" (In the absence of Mosquito).

Tks

http://img26.photobucket.com/albums/v79/Tony_Wizzz/il2/307logo.gif

http://img26.photobucket.com/albums/v79/Tony_Wizzz/il2/RAF%20307%20Squadron%20Wijaszko/

http://www.geocities.com/skrzydla/

wright_7
04-04-2004, 05:18 PM
Hi, Airspeed to low = Stall

Taylortony
04-04-2004, 06:11 PM
I am trying to advance my flying, this is where my main difficulty lies, what are the condtions where this occurs, presumably it is mainly related to speed and angle of banking,

1) Explanations pls?
2) Can you feel it happening?
3) How can you attempt to correct?

OK A stall happens when a wing is at a high angle of attack to the relative airflow and low speeds, A wing has a twist in it, this allows the wing root to stall first, the advantages of which allow the ailerons to maintain control as the wing outboard has not stalled and to alert the pilot to the onset of stall. This is done because the stalled wing root produces dirty air which as it goes over the tailplane causes buffet which is felkt through the controls and alerts the pilot to the on set of stall..
when it start to stal you should see the whole thing start to shake on the screen, at this point ease of in the turn or drop some flap, flaps increase the aerofoil section of the wing, increases lift and reduces the speed before stall happens.
therefore keep your speed as high as possible, in a turning flight drop flap if it slows and starts to buffet..... i can have landing flap on in a tight turning fight.... but keep spped up is the key.

Ok you gou into a stall drop the nose build up speed and recover...... going into a spin close the throttle centralise controls drop flaps helps put in opposite rudder and if it does not come out put in a fist full of power to snap it out then recover........................................... ................. hope it helps

Some explanations of how other in-flight "phenononem" would also be appreciated, head shake, gyro, flutter etc.

gyro is gyroscopic forces you have an engine and a ruddy great prop going one way, this will try to rotate the aircraft the same way, want an example? the Spit has more air in one tyre than the other to attempt to alleviate it on taxying,

Not got to complex engine managment yet, so eave that for now, I need to master flight characteristics first!

Use the Spitfire for example. this is the aircraft I want to fly "properly" (In the absence of Mosquito).

BlitzPig_DDT
04-04-2004, 06:16 PM
"Streamers" start to trail from the wingtips like white tip smoke (press the T key. like that only white and much shorter), you also hear a scraping, dragging type wind sound known as buffeting that indicates the onset of departure. On some planes, the view even shakes a little bit, and on planes that have them, leading edge slats open.

As you move through the air and move the stick, the control surfaces work against the airflow and pitch, roll, or yaw the plane. As this happens, the wings begin to take on an angle relative to the airflow. This is known as Angle of Attack.

The greater the planes elevator authority, the more it can increase it's Angle of Attack. Different planes have different capabilities here. Some can stall even at high speed, some can't stall (by jerking the stick) even at low speeds.

When the AoA changes, the direction the plane is moving begins to change and the AoA gradually decreases once input is stopped.

This means, the slower and smoother you are with inputs, the faster you can stay (drive in your car, put your hand out the window, and cut through it with a knife edge, then rotate it to provide a "wall" against it. That force against it is working on a planes wings, bleeding speed and E, and also producing G forces), but the slower you change direction too. It's a balancing act that experience helps you get better at.

Best advice is to take the plane up in the QMB alone and wring it out. Try aerobatics and see what it takes to stall and how much you can push it.

As to countering it, relax back pressure on the stick. If you stall in a turn in FB:AEP in almost any plane you will spin now. Fight that by immediately feeding full opposite rudder and relax pressure on the stick. The quicker you react, the less likely you are to enter a spin.

Get into a spin, and you want to release the stick and apply opposite rudder to stop the spin then get the nose down and build speed to recover. Don't pull out too hard or too soon as you will re-enter a spin and secondaries are usually deadly.

==================================
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Come and spam on our front porch.

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Chuck_Older
04-04-2004, 06:26 PM
Doesn't the documentation just stink?

Sorry, Oleg and Co., but while your efforts at flight sims are laudable and represent the current level of excellence in the genre, your efforts at documentation suck http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif Not bashing, just observing that it is assumed that the new IL*2:FB player already knows a fair bit about the principles used to simulate flight.


Not one word about power-on stalls and spins that I can remember in the manuals http://ubbxforums.ubi.com/images/smiley/blink.gif


The old Dynamix titel, "Aces of the Pacific" did a much much much better job preparing the virtual pilot for 'flight', and the software title was about 10 years behind the State of the Art of being able to really simulate things that the AOtP manual described. Now Il*2:FB is here, and the documentation is pathetically lacking- yes I know how the printed material costs more than the other elements of the title- but you could always put this stuff on a second CD.

*****************************
Punk Rockers in the UK, they won't notice anyway. They're all too busy fighting for a good place under the lighting~ Clash

Loco-S
04-04-2004, 06:58 PM
I hope this will explain it in more detail.
http://mywebpage.netscape.com/kurbalaganda/stallspin01.jpg
http://mywebpage.netscape.com/kurbalaganda/stallspin02.jpg
http://mywebpage.netscape.com/kurbalaganda/stallspin03.jpg
http://mywebpage.netscape.com/kurbalaganda/stallspin04.jpg
http://mywebpage.netscape.com/kurbalaganda/acceleratedstall+.jpg

http://mywebpage.netscape.com/kurbalaganda/Loco-S.gif
Armis Bela, non venenis geri

Flightvector
04-04-2004, 11:14 PM
Unfortunately, the definition of a stall can't be oversimplified by saying high AOA exposes the wing as a wall instead of a knife edge, air is a fluid, not a bunch of bullets, so this definition is a bit insufficient. Stalls also generally have very little to do with elevator authority at low to moderate speeds (Unlike some planes in IL-2), since very few planes have limited elevator authority that it would affect how different planes stalled below maneuvering speed (i.e. all cars can lock their wheels below 60 mph, so why install stronger brakes? Similarly nearly all planes can stall below maneuvering speed. At high speeds, G-force overstress limitation or compressibility step in).

In true definition, a stall is when the vacuum generated by the unwetted upper-rear surface area of a high AOA wing requires such a high degree of acceleration to keep the air flowing and attached over the upper surface that the vacuum is unable to overpower the rearward momentum of the air, and thus the air separates from the wing surface and becomes turbulent due to the lack of a guiding surface. When air separates, it can no longer suspend the wing since no organized velocity can form over it, and Bernoulli's law comes into play here, where high fluid velocity creates lower pressure; lack of organized velocity negates any collective drops in pressure.

As far as procedures (recognition, prevention, and recovery) go, the previous article posted sums it up extremely well.

Fehler
04-05-2004, 04:37 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Flightvector:

In true definition, a stall is when the vacuum generated by the unwetted upper-rear surface area of a high AOA wing requires such a high degree of acceleration to keep the air flowing and attached over the upper surface that the vacuum is unable to overpower the rearward momentum of the air, and thus the air separates from the wing surface and becomes turbulent due to the lack of a guiding surface. When air separates, it can no longer suspend the wing since no organized velocity can form over it, and Bernoulli's law comes into play here, where high fluid velocity creates lower pressure; lack of organized velocity negates any collective drops in pressure.

<HR></BLOCKQUOTE>

Perfectly put.

Incidently, if you work on cars at all, this is the same principal that affects your carb at different stages of manifold vacuum. Understanding the relationship between air mass intake and above/below manifold pressures are essential to tuning a good racing carb.

Hydrodynamics... it's all about the water...

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Taylortony
04-05-2004, 10:39 AM
Originally posted by Flightvector:

In true definition, a stall is when the vacuum generated by the unwetted upper-rear surface area of a high AOA wing requires such a high degree of acceleration to keep the air flowing and attached over the upper surface that the vacuum is unable to overpower the rearward momentum of the air, and thus the air separates from the wing surface and becomes turbulent due to the lack of a guiding surface. When air separates, it can no longer suspend the wing since no organized velocity can form over it, and Bernoulli's law comes into play here, where high fluid velocity creates lower pressure; lack of organized velocity negates any collective drops in pressure.

Or to put it in laymans terms, When the Angle of Dangle gets sufficent the Center of pressure moves forward and falls off the front of the wing.................. http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

XyZspineZyX
04-05-2004, 11:54 AM
Keep in mind that FB/AEP stall and spin behavior is for the most part, canned and slapped onto planes' flight models very haphazardly. Some planes with docile stalls and little proclivity to enter a flat spin (like the 109G2, and earlier, the 109F models, and the Zero) are prone to do both in this sim, while others that were known killers (P39s, FW190s) get much more of a break on this behavior than they should.

Also, the procedure for stopping a spin in this sim (full flaps, throttle full back, rudder full in counter direction of spin) is not the proper recommended method to actually recover. One would likely NOT deploy full flaps, nor fully throttle down. The counter rudder is a proper response, however, along with some measure of throttle control, especially to counter a spin in the direction as the engine torque.

TX-EcoDragon
04-05-2004, 12:01 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by tonywizzz:
I am trying to advance my flying, this is where my main difficulty lies, what are the condtions where this occurs, presumably it is mainly related to speed and angle of banking,

1) Explanations pls?
2) Can you feel it happening?
3) How can you attempt to correct?

Some explanations of how other in-flight "phenononem" would also be appreciated, head shake, gyro, flutter etc.

Not got to complex engine managment yet, so eave that for now, I need to master flight characteristics first!

Use the Spitfire for example. this is the aircraft I want to fly "properly" (In the absence of Mosquito).

Tks

http://img26.photobucket.com/albums/v79/Tony_Wizzz/il2/307logo.gif

http://img26.photobucket.com/albums/v79/Tony_Wizzz/il2/RAF%20307%20Squadron%20Wijaszko/

http://www.geocities.com/skrzydla/ <HR></BLOCKQUOTE>

1)
The above points may have explained it to you, but:
Put simply, the faster you go, the harder you can pull without the wing losing lift at the critical angle of attack. So at the "stall speed" you can only pull 1G (in other words, maintain level flight) at speeds above this you can pull more G's without the wing losing lift. Becasue of this, a wing can stall at any speed, it is the angle of attack that is the deciding factor. Be gentle on the elevator at lower speeds and get a feel for how hard you can pull at the various speeds.

2) The sim actually provides a pretty good indication that a stall is near, you should notice headshake/buffetting, and you should hear an increase in slipstream sound. When pulling the stick very quickly you may stall the wing before noticing these indications, in that case recovery is in order.

3) Often simply releasing the back stick force quickly is enough, but you may need to actually push the stick forward and apply rudder opposite the rotation direction. If a spin develops from the stall then similar recovery inputs are needed, usually this is power off, ailerons neutral, rudder opposite the rotation, elevator forward.

Some aircraft in the sim have peculiar behaviours and reward things like gear extension or power increases, though I try to avoid such antics. ;-)

The great thing about teh sim is that there is nothing to lose, go offline and try flying level at about 450 kmh, then pop the stick back really quickly, then do the same at 400, then at 350 or 300, then at 250, and then at 200. you will see that the available G goes down as you slow, and that the stick force you can apply must go down as well. As soon as the aircraft starts to roll, pop the stick forward and give it rudder opposite the roll. Soon you should be able to do these accelerated stalls without any altitude loss. If you let these turn into spins there will be altitude loss.

S!
TX-EcoDragon
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darkhorizon11
04-05-2004, 12:09 PM
Actually a stall can happen at any airspeed or configuration. Its a really complicated topic as I've taken an entire course devoted to the physics of stalls, spins, and stability. Your best bet is to do a search on previous posts theres been many. Don't be confused though the best stall model on a flight sim is Microsoft Flight Sim 02 (I haven't played 2004) yet...

The_Red_Spoon
04-05-2004, 03:10 PM
Can someone tell me if the following is correct (from a realism POV).

I was experimenting with stalls on the La-7. It maintains a level climb until speed drops below 170kph (engine off etc.), and the stall ALWAYS takes the form of a violent dive/roll to the left or right (easily corrected by dropping the nose and rolling in the other direction).

I just can't get the thing to just drop forwards/backwards out of the sky without rolling or spinning (i.e. a nose stall?) Are the stall routines in AEP hardwired? Should I able to do what I'm attempting to do?

Taylortony
04-05-2004, 03:49 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by darkhorizon11:
I've taken an entire course devoted to the physics of stalls, spins, and stability. <HR></BLOCKQUOTE>

Me to... It was a 10 Pinter Session in my Local http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif but i got to experience it all on the long walk home http://ubbxforums.ubi.com/images/smiley/88.gif

TX-EcoDragon
04-05-2004, 04:29 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by The_Red_Spoon:
Can someone tell me if the following is correct (from a realism POV).

I was experimenting with stalls on the La-7. It maintains a level climb until speed drops below 170kph (engine off etc.), and the stall ALWAYS takes the form of a violent dive/roll to the left or right (easily corrected by dropping the nose and rolling in the other direction).

I just can't get the thing to just drop forwards/backwards out of the sky without rolling or spinning (i.e. a nose stall?) Are the stall routines in AEP hardwired? Should I able to do what I'm attempting to do?<HR></BLOCKQUOTE>

It isn't quite correct, most aircraft should allow you to keep a wing from dropping by aggressive rudder use. The 1G stall takes the back seat to the accelerated stalls, I think that this is appropriate for a combat sim, but of course many of us seek perfection!

http://forums.ubi.com/eve/forums?q=Y&a=tpc&s=400102&f=23110283&m=506105692&p=1

S!
TX-EcoDragon
Black 1
TX Squadron XO
http://www.txsquadron.com

Member-Team Raven
http://www.waynehandley.com

First Slot Pilot Aircraft #4 of the Virtual Haute-Voltige Team
http://www.vhvt.com/

http://www.attitudeaviation.com/

http://www.calaggieflyers.com

http://www.txsquadron.com/uploaded/TX-EcoDragon/ravenvert.jpg

E_Temperament
04-05-2004, 09:02 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by The_Red_Spoon:
Can someone tell me if the following is correct (from a realism POV).

I was experimenting with stalls on the La-7. It maintains a level climb until speed drops below 170kph (engine off etc.), and the stall ALWAYS takes the form of a violent dive/roll to the left or right (easily corrected by dropping the nose and rolling in the other direction).

I just can't get the thing to just drop forwards/backwards out of the sky without rolling or spinning (i.e. a nose stall?) Are the stall routines in AEP hardwired? Should I able to do what I'm attempting to do?<HR></BLOCKQUOTE>

It sounds to me like you are using the elevator too roughly, try easing the stick back much more gently while entering the nose high stall. You should be able to hold the nose high while the plane is sinking and losing height without dropping a wing, the plane will be buffetting quiet a bit by this stage, then relax the elevator and it will drop the nose. If it is dropping a wing you are basicly going past the stall and have started to enter the first stages of a spin.