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BillSwagger
07-31-2009, 05:50 PM
I know the principals behind a stall as far as increasing the angle of attack or not having enough airspeed.

My question is about high altitude stalls, which i wouldn't think would be any different.

Hopefully people who've actually flown a plane can help answer this question.

I notice in game i will be in a steep climb or zoom climb, and my IAS will be begin to reach stall speeds however my TAS is still quite high.
Despite having climbing momentum the plane will whip into a violent spin with the slightest elevator deflection. Is this something that occurs in real life in thinner air?? My presumption is that the thinner air would create less lift and less force against elevator deflection so it shouldn't create as extreme of a spin as it might create at lower altitudes.

What do i know, though, i've never actually flown in a WW2 plane above 7000M.

Has anyone else noticed this when they climb up high and approach stall speeds, then have your plane suddenly spin with little or no elevator deflection??

Freiwillige
07-31-2009, 06:14 PM
IAS is important to WWII pilots and its what they go by. (Its also all they have) http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

But regardless it is an important indicator of what is available performance wise. IL2 high alt modeling is a bit broken, that is a fact since the Sim was designed around low level IL2 flight and 20 to 30k was unheard of in an IL2. I bet most never exceeded 10k in reality!

But I do believe that as far as IAS is concerned once its low and your at high alt you can and will spin since you have little air to steer with but you still have the massive torque!

M_Gunz
07-31-2009, 07:20 PM
Originally posted by BillSwagger:
I know the principals behind a stall as far as increasing the angle of attack or not having enough airspeed.

It's totally about angle of attack and the airspeed part is a result of that.

Lift goes by AOA and speed. The slower you go, the more AOA you need to make the same lift. Up to critical AOA you
can get more lift at the same speed by increasing AOA and after critical AOA the wing is stalled. So you can only
go so slow and keep the plane up doing whatever it was doing like flying level or turning or whatever.

Wiki on AOA. (http://en.wikipedia.org/wiki/Angle_of_attack)


My question is about high altitude stalls, which i wouldn't think would be any different.

Hopefully people who've actually flown a plane can help answer this question.

NP. Been there, done it.
They aren't different. Exceed AOA and you stall.


I notice in game i will be in a steep climb or zoom climb, and my IAS will be begin to reach stall speeds however my TAS is still quite high.

Due to air density dropping with increased alt, TAS doesn't tell you how much lift you get. However since the lower
density is why IAS is lower than TAS you go by IAS not only for stall but for all maneuvers. Go high enough and you
won't be able to turn more than slightly without losing alt.


Despite having climbing momentum the plane will whip into a violent spin with the slightest elevator deflection. Is this something that occurs in real life in thinner air?? My presumption is that the thinner air would create less lift and less force against elevator deflection so it shouldn't create as extreme of a spin as it might create at lower altitudes.

Going into a spin happens whenever you stall in uncoordinated flight except for turns you can have excess bank and not
spin. Usually you can tell by The Ball but flying really slow and level you have to keep the wings level (lined up
with the horizon is how I do it) since The Ball has too much delay.

BillSwagger
07-31-2009, 07:26 PM
Stall behavior is strange at higher altitudes and it varies on the plane.
It just seems weird when your moving at 300kph at a 60 degree climb, and you roll to one side and it puts in a very fast spin. I understand the physics of the stall but what i don't understand is if there is less air to create lift, then wouldn't there also be less air to create as extreme of a spin?? or am i missing something here.


Note: its not like i'm jerking the stick or pushing the envelope. It just pops into a rather quick spin, out of seemingly thinner air. So i wondered if that was still possible or even more likely at high altitudes.

Freiwillige
07-31-2009, 08:05 PM
Less air makes spinning easier since there are less aerodynamic forces acting on your wings etc.

For example if air was really thick like water do you think a plane could spin?

The spinning is caused by torque and gyroscopic effects which have little to do with air density.

AndyJWest
07-31-2009, 08:07 PM
It would probably help if you could be a bit more specific, so we can try it for ourselves. A .ntrk file or at least plane type and altitude will do at a pinch. I seem to find spinning at altitude easier, and often use it (offline) as a quick way of losing hight, though you need to know the plane's recovery characteristics to be safe, and I'd never get below about 2500m before starting recovery, even in the safest planes.

There's a lot to be said for practising spins at altitude: that way you get to recognise them as they happen, and (sometimes) catch them before they kill you at lower altitude. Dosn't always help though: I spun in twice today online in firstly a Spit IX, which is usually fairly tame in this regard - I was being chased by a 109 at 100m or so altitude, which at least gives me an excuse. The second spin I was in a 109 at about 500m altitude, and the Buffalo(!) I was chasing was low and slow beneath me: Trying to get into a decent attack position I pulled too hard in a vertical bank, and promptly performed a spiraling belly-flop. http://forums.ubi.com/groupee_common/emoticons/icon_frown.gif

I've heard it said that the spin behaviour modelling in IL-2 is one of the FM's weaker points, but it has got to be better than Microsoft's 'flight' simulator, where the instructions for performing a spin are basically 'pull the stick hard back and to the side, applying full rudder and hold it there. All you get from this is a tight vertical barrel roll, rather than the 'spinning on its axis' effect that IL-2 does, and that you see in real life with an aerobatic aircraft.

Loco-S
07-31-2009, 08:17 PM
I hope you have powerpoint, or Open office to open the link, its from the FAA:

http://www.faa.gov/other_visit...ighAltOperations.ppt (http://www.faa.gov/other_visit/aviation_industry/airline_operators/training/media/Appendix%203-E_HighAltOperations.ppt)

BillSwagger
07-31-2009, 10:27 PM
Originally posted by Freiwillige:
The spinning is caused by torque and gyroscopic effects which have little to do with air density.

The plane will spin either direction regardless of torque, so i'm not sure i understand what you are saying.

I was attempting to mic mic this but its actually kind of difficult to do.

What i did find is something very similar.
After the top end of a loop and being inverted, the plane begins to make its way back down, but there is a tendency for the nose to spin upward??? ...this spin upward, against gravity has me puzzled.

http://www.filefront.com/14169623/stallbehavior.zip


You can try and take a plane into a loop and after the plane gets over the top tug on the stick a little more to put it into a stall at 7500M+.

Its a strange effect.

Now imagine that happening with no warning.

M_Gunz
08-01-2009, 02:57 AM
Originally posted by BillSwagger:
Stall behavior is strange at higher altitudes and it varies on the plane.
It just seems weird when your moving at 300kph at a 60 degree climb, and you roll to one side and it puts in a very fast spin.

First, 300 kph IAS or TAS? But that's not the more important point.

When you roll to one side your lift is no longer pointing straight down, there is less keeping you up. It's not a problem
if you let the plane drop as need be and fly along a more ballistic path but if you try and keep the nose up and the path
above what your flight can maintain -- then oh yes it becomes a very big problem. Gravity forces you down and your lift
forces you to the side, you're aligning your two major forces in a way that if you hold the plane against them can drive
a nasty spin. If you don't push it but actually back off then you'll fly an arc and get away with it, it's up to you.

As you roll, the wing that has the aileron going down now has a higher AOA on that side for the entire length of the aileron,
and more drag even if it hasn't crossed over into stall. The other wing has less AOA and less drag. That puts a yaw/turn
force on the plane that slows the wing you wanted to go up and speeds up the wing you wanted to go down as well as turning
the fuselage which then blocks air going over the base of the slower wing, cutting lift even more. If you counter that by
pushing the stick over more then the situation gets worse and anywhere in there the wing you wanted to go up stalls deeply.

The stalled wing drags really hard and goes back and down. The other wing going forward gets more lift and jerks up, they
do this together and each works with the other. It yaws the nose hard and the spinning prop turns the yaw into a circular
motion that may counter the spin you just entered or may add to it but you may not notice since the gyroscopic precession
due to the prop is a Minor force compared to the drag on the stalled wing and the difference between the lift on the two
wings.

At that point you have just entered a spin and can get out pretty quickly by easing up on the stick, backing off on the
throttle and taking gentle countermeasures. If you don't understand or even notice then the usual reaction is to pull
harder and there is no better way to make the spin worse, to feed it while pushing the plane as hard into the center
where it will spin easier and maybe break loose into a flat spin. With any luck at all you'd be upside down too.

All I can say is to practice these things when your attention isn't on a target or pursuer until you can recognize what's
happening and see it before it even starts, to know when you're near the edge before you have crossed it. Those who can't
tell a stall from a spin and use the words interchangeably do not even have a clue. They may read explanations but they
don't follow up and work it through in practice so it's a surprise every time as they don't know what to watch for and
don't watch anyway, they are fixated on the fight that they consider all the practice they need. Only a gamer does that,
IRL you learn to fly before you shoot, you learn tactics before you fight, and only then do the real lessons begin.

People write to me how wrong I am to say practice flying, practice gunnery and only then fight because it's not what they
call FUN. How much FUN is it spinning out of fights let alone with all the other penalties of flying like c.r.a.p? Do
they even notice? Fly with mudhens long enough to get mediocre and anyone can roll up a big ego-satisfying score. I guess
that must be hard work and FUN all rolled into one. As for me, I think I get more just practicing moves those guys would
and have called cheating just to see.

BillSwagger
08-01-2009, 03:36 AM
thanks for this detailed explanation, Gunz.
This doesn't relate to the topic, but as for practicing i think its important to know when you are approaching a stall, but also how to use the spin to your advantage.

Here's a snippet from a dogfight between a P-47 and a La-7, where i use the snap roll to gain position.
http://www.filefront.com/14170755/snapper.ntrk



In regards my stall question, is....if the wing has less lift at 30,000ft, then shouldn't the spin be less extreme or not as fast than it is at 10,000ft??
I guess it could gain the momentum in prolonged spin, but i wonder if how a stall spin is different at 30,000ft than it is at 10,000ft because of the thinner air.
There might not be any difference, i'm not sure.

M_Gunz
08-01-2009, 04:33 AM
One wing stalls before the other and then you spin. The drag force on the stalled wing is by IAS high or low.
However your TAS is higher so you have more energy of motion behind the plane that has lost control.

A spin may save your butt some time but it also leaves you as an easy target during recovery when you can't do
more than steady the plane while trying to gain enough speed to fly. It costs both altitude and speed. A
barrel roll works better if you have the speed and if you don't then that's your fault or the other guy just
outclasses you terribly one way or another. As for a bag of tricks move... there's better tricks by far.

erco415
08-01-2009, 07:48 AM
M.Gunz, perhaps it's how you've worded it, but a few of your statements on lift, stalling, and turns seem to me to be incorrect. I'm at work now, so I'm limited to what I can do with the phone, but I'll try and point out what I'm seeing this afternoon. I'd do it now, but the pax are due any minute.
Cheers!

AndyJWest
08-01-2009, 09:12 AM
Originally posted by BillSwagger:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Freiwillige:
The spinning is caused by torque and gyroscopic effects which have little to do with air density.

The plane will spin either direction regardless of torque, so i'm not sure i understand what you are saying.

I was attempting to mic mic this but its actually kind of difficult to do.

What i did find is something very similar.
After the top end of a loop and being inverted, the plane begins to make its way back down, but there is a tendency for the nose to spin upward??? ...this spin upward, against gravity has me puzzled.

http://www.filefront.com/14169623/stallbehavior.zip


You can try and take a plane into a loop and after the plane gets over the top tug on the stick a little more to put it into a stall at 7500M+.

Its a strange effect.

Now imagine that happening with no warning. </div></BLOCKQUOTE>

From the .ntrk, you seem to be doing a flick roll at the top of the loop. These things are easier to see with smoke on:

http://i958.photobucket.com/albums/ae65/ajv00987k/SpiSpin0.jpg
http://i958.photobucket.com/albums/ae65/ajv00987k/SpitSpin1.jpg
http://i958.photobucket.com/albums/ae65/ajv00987k/SpitSpin2.jpg

This is induced simply by pulling too hard as the aircraft decelerates in the climb. My examples flick earlier, resulting in the aircraft spinning while still being carried upwards by inertia. Note that the only control input to induce this is back stick, the flick roll comes free of charge. In another topic I included a .ntrk pf a P38 doing the same thing, which (without trying to kick the whole debate off again) seems to indicate that lots of torque is not necessary to start the flick: I think I'll try it sometime in a jet with the engine off, just to confirm this. My example is at lower altitude, so this is probably not that significant a factor.

For those interested:
Clicky Clicky for ntrk download (http://www.datafilehost.com/download-271db478.html)

And yes, when it happens unexpectedly, it can ruin either (a) your aim, or (b) your day, depending on altitude, aircraft spin recovery characteristics, and proximity of bandits (though they may be laughing too much to remember to shoot...) http://forums.ubi.com/images/smilies/88.gif


[PS Edit]

Tried this in a Ta-183, engine off. It only seems to flick if you apply rudder as it slows (insufficient elevator response to cause stall otherwise?), though speed and timing will be fairly critical as to exactly what happens. Take care though, my first attempt resulted in a flat spin which took a long time to recover, and needed full down elevator, as well as opposite rudder before it responded.

M_Gunz
08-01-2009, 02:14 PM
Originally posted by erco415:
M.Gunz, perhaps it's how you've worded it, but a few of your statements on lift, stalling, and turns seem to me to be incorrect. I'm at work now, so I'm limited to what I can do with the phone, but I'll try and point out what I'm seeing this afternoon. I'd do it now, but the pax are due any minute.
Cheers!

I'm trying to do this without the lift equation for a person who would be lost if I did. I didn't state every condition since
and part by then I might as well drag out the lift equation.

erco415
08-01-2009, 03:53 PM
Oh, that's not the issue. The things that I'm wondering about are somewhat more basic. I'm just getting on the airline for the ride home, I'll write what I'm wondering about and (hopefully) post around 9CDT.

Freiwillige
08-01-2009, 05:08 PM
you say that against gravity the nose tends to want to go upwards?

That is Gyroscopic effects!

Tully__
08-01-2009, 05:42 PM
Originally posted by erco415:
Oh, that's not the issue. The things that I'm wondering about are somewhat more basic. I'm just getting on the airline for the ride home, I'll write what I'm wondering about and (hopefully) post around 9CDT.
Gunz's post seems all good to me. Gunz is generally very good when it comes to descriptions of practical aerodynamics, he has the background and the need to get it right http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

BillSwagger
08-01-2009, 05:58 PM
these are all good explanations of stalls.

My question revolves around lift.
It seems that at high altitudes there would be less lift. If there is less lift/drag, then the spin should be less severe or take longer to build momentum. (unless you are using heavy elevator to induce a heavier spin)
I know gyroscopic forces can have an effect on the stall, but when i turn them off, the spin still occurs and will spin either direction.
That's not even what i'm debating.

M_Gunz
08-01-2009, 07:21 PM
I will try to make this more clear.


One wing stalls before the other and then you spin. The drag force on the stalled wing is by IAS high or low.

So here you have the beginning. One wing is stalled, has less lift so it's pulliing down if you were level and pulling back
pretty hard while the other wing is not stalled, has more lift and pushing up if you were level and not dragging as much.

The whole plane is being rolled if you were level and being turned towards the stalled wing as hard as you hold back for.


However your TAS is higher so you have more energy of motion behind the plane that has lost control.

Once the nose is far enough to the side it's a bit like hitting the ground in a fall. The air may be less dense but your
tumble has the energy of your TAS behind it which is less for the same IAS down low. IAS determines how much force the
air puts on the plane but the kinetic energy is by the TAS, squared.

Not to mention even down low there's a big difference between stalling slow and level when you don't have the stick hauled
back and stalling in a 60 degree climb where you do.

The tail is a wing that balances against the weight of the nose, pushing down in level flight. The tail is set to stall
in many conditions before the wing does so the nose will come down of its own accord, no longer being balanced by the
stalled tail plane. How fast and hard that happens has a lot to do with how the plane was flown up to then.

AndyJWest
08-01-2009, 07:39 PM
Originally posted by M_Gunz:

...

The tail is a wing that balances against the weight of the nose, pushing down in level flight. The tail is set to stall
in many conditions before the wing does so the nose will come down of its own accord, no longer being balanced by the
stalled tail plane. How fast and hard that happens has a lot to do with how the plane was flown up to then.

I'm 99% certain that this is incorrect, in that the tailplane is usually set at a lower angle than the wing, but at high angles of attack it will be generating an upward lifting force: it is because the wing stalls before the tail has a chance to that the nose drops. Also, the centre of pressure of the wing will normally move forward as AOA increases, so if the tailplane stopped producing a force, the nose would rise. I'll look on the net tomorrow to see if I can find a clear guide to aircraft stability, it's way past bedtime...

[ PS Edit ----- ]

A good starting point for the question:
Wikipedia article (http://en.wikipedia.org/wiki/Center_of_pressure)

erco415
08-01-2009, 07:43 PM
M_Gunz, the last paragraph of your first post had a couple of things that raised my eyebrows. First, you state that spins occur when you stall in uncoordinated flight, "except for turns". All of the aircraft that I've taught stalls and spins in would spin out of a turn just fine. You go on to say that the slip/skid indicator (the ball) is of little use when flying slowly and level, because it "has too much delay". Did you mean ingame? Because this also contradicts RL experience. Keeping your wings level tells you little about how coordinated you're flying.

Your second post also had me wondering. Firstly, you make it sound like making a constant altitude turn is a risky maneuver, which of course it isn't, but it's unclear just what sort of conditions or scenario you're referring to. I think it would be helpful to explain a lift vector diagram, as you sort of referred to, to better illustrate this point.

A simple lift vector diagram can clearly illustrate why an airplane in a banked turn requires more lift to maintain level flight. It can be drawn thusly: Begin by drawing a small circle that represents the aircraft's fuselage viewed from behind. Add a line to represent the vertical stabilizer and two more lines on either side of the fuselage for the wings. Next, draw a short vector (an arrow) extending downward from the bottom of your airplane to represent the force of gravity. This vector will always point in the same direction, down. Next, draw a vector pointing up, perpendicular to the wings, to represent the force of lift, the 'lift vector'. This line will always be drawn perpendicular to the wings. Remembering that a vector's length represents it's magnitude, in this case the amount of force, the length of the line you drew for gravity represents the aircraft's weight. To remain in level flight, you must then generate enough lift to equal the pull of gravity, thus your 'lift' vector must be as long as your gravity vector. This is true at any altitude, high or low.

Now we'll make things more interesting. Redraw your diagram, with lift and gravity vectors of equal length still, but now with the airplane in a 45 degree bank. You can see that lift is no longer countering gravity directly, so what can we do? In this condition we must consider the vertical and horizontal components of lift.

In our original case, all of the lift generated acted opposite gravity. This is the vertical component of lift. If we were to bank our airplane 90 degrees to the horizon, all of the lift our wings generate would be horizontal component. A 45 degree bank, then, causes the lift generated to have a horizontal and a vertical component. The horizontal component is what makes us turn. Here now, for you folks playing along at home, is the only tricky bit: On your 45 degree diagram we are going to draw a square around the lift vector where the lift vector goes from one corner of the square to the opposite corner. The side of the square that is opposite our gravity vector is the vertical component of lift, the side starting at the airplane and extending perpendicular to the vertical component is the horizontal component of lift.

Now, try and imagine how the square you drew would change into a rectangle and finally a line ( the level flight and 90 degree diagrams) as the aircraft rolled into a bank. The further you roll from wings level, the greater the horizontal component becomes while the vertical lessens. Our 45 degree diagram makes it clear that the amount of lift required to sustain level flight, unbanked (where all lift is vertical component) is not enough to counteract gravity in a banked condition. So what do we do? Do nothing and we descend. To increase the vertical component of lift, to maintain level flight, we must increase the total lift generated and one way we can do this is by increasing AOA, ie, pulling on the stick. Increase total lift until the vertical component again equals gravity and we maintain level flight.

Playing with this diagram can answer many questions about aircraft performance. Remember that generating lift always generates drag. This is the reason your airplane bleeds energy in a turn. It's fun to think about, and the next time you hear some fighter jock going on about putting the lift vector on the bandit, you'll know what he's talking about.

Which brings me back (finally!) to M_Gunz's point about turns and the danger of such. There is nothing inherently hazardous about rolling your lift vector off vertical or sustaining a level turn. Where you can get into trouble (and perhaps this is what you meant, M_Gunz) is when you get so intent on pulling your nose around to the bandit that all that lift you're generating has slowed you to your (probably accelerated) stall speed, and if you're not coordinating your turn properly, an inadvertant spin.

(In case that term, accelerated stall, is foreign to you, it refers to the fact that stall speed increases the harder you pull your airplane around. Your lift diagram can explain why, with some contemplation)

Moving on to M_Gunz's description of a spin entry, which focuses on rolling into a turn (which is confusing as earlier you stated that turns reduce the chances of a spin) as it's cause, a few things stand out for comment.

First, as the airplane rolls into it's turn, the wing going 'up' is making more lift, thus more drag, and causes the airplane to yaw opposite the direction the turn. This is known as 'adverse yaw' and it is countered by the application of rudder in the direction of the turn. You are using enough rudder, ie, making a coordinated turn, when the ball is centered. It should be pointed out that adverse yaw is only present while the aircraft is rolling into or out of it's bank, which is to say that little aileron or rudder input is required once you're established in your turn. Thus, when M_Gunz states that "the fuselage ... Then blocks the air going over the base of the slower wing" he is referring to a situation in which the turn is not properly coordinated.

Rolling an airplane vigorously can cause a stall, the modern aerobatic mounts can now roll so quickly that then can stalled conditions at what would otherwise be rather small angles of attack. But in most other situations it is not the cause of the stall/spin. The stall is caused by excessive AOA, the spin by stalling uncoordinated, that is, without the ball centered. This uncoordinated stall results in one wing being more fully stalled than the other, which causes a rolling/yawing motion around the aircraft's center of maneuver (which for purposes of our discussion can be considered it's center of gravity). The prop has little to do with the spin entry, or it's continuation, though it may modify the nature of the stall/spin entry. The spin is then simply a rolling/yawing autorotation sustained by an imbalance of lift.

Generally speaking, a properly designed and built, and I might add, not shot-up, airplane will not spin if it is properly coordinated, the ball being centered. There can be some exceptions. Some aircraft exhibit a vicious wingdrop at the stall that can lead to a spin if left uncorrected. Although not modelled in IL2, a torque roll could complicate things. A mishandled 'hammerhead turn' can present the opportunity for an airplane to misbehave. Some aircraft, and I'm looking at you, P-39, have very particular procedures that must be followed in the event of a spin. But mostly, it's pretty simple.

In reference to high altitude maneuvering: For reasons that, if stated, would make this post epic in it's length, you simply can't maneuver as aggressively at high altitudes as you can at lower altitudes. Try to be smooth, gracefull.

In any case, two things should now be clear: First, stalls and spins are the airplane's way of telling you that you're pulling too hard on the stick and to 'step on the ball'! Second, it's probably not the best idea to have Erco compose his posts on a three hour airline leg- jeepers, the eyestrain!

BillSwagger
08-01-2009, 07:48 PM
I will try to make this more clear.
I think gunz is just trying to keep his answers in the context of my question.
There is a lot more to flying and stalling a plane in real life.

Gunz,

it makes sense what you are saying to me.
The wing stall is based on the IAS reading.
Part of me was thinking that the momentum (TAS) was fast enough to impede the spin.

The IAS is also a measure of density, it does not mean that the air isn't moving fast over of the wing. So my perception that the spin would be slower was probably flawed because of that.

It still doesn't equate that way in my mind. (call me slow), but this is how i'm seeing it.
Assuming similar stall conditions other than altitude:

Denser air = more lift = more spin

thinner air = less lift = less spin

So i'm still not quite grasping why a stall spin would be the same severity at high altitude.

erco415
08-01-2009, 08:21 PM
The thing is, you're generating the SAME amount of lift at high altitude as at low.


Quite right Mr. West, the tail
is NOT stalling. Tail stalls are bad

M_Gunz
08-01-2009, 08:47 PM
Originally posted by erco415:
M_Gunz, the last paragraph of your first post had a couple of things that raised my eyebrows. First, you state that spins occur when you stall in uncoordinated flight, "except for turns". All of the aircraft that I've taught stalls and spins in would spin out of a turn just fine.

I used to think so but Viper and TX_EcoDragon stated it differently. In a turn, a bit of slip is actually stable while
skid is really bad. Take it up with them. IIRC tht might also be what John Denker wrote, I'd have to read a few screens
at his site to be sure.


You go on to say that the slip/skid indicator (the ball) is of little use when flying slowly and level, because it "has too much delay". Did you mean ingame? Because this also contradicts RL experience. Keeping your wings level tells you little about how coordinated you're flying.

In game and in real life, the ball is in a tube full of liquid and does not move immediately in all conditions. It is
especially under-reliable under even slight negative Gs. Get slow and level in the back side of the power curve and it is
useless. I also have the word of at least one aerobatics pilot on that. Keeping the wings level does just that, it keeps
the wings level which is how you stay up in that tricky situation. You can chase nits, I know what works and the pedal
dance is as I described. If I doubted that then I'd say so. Do you IRL fly deep into the backside of the power curve?
There are people here who do, I can send some PMs and maybe get definite answers from folks you can believe.


Your second post also had me wondering. Firstly, you make it sound like making a constant altitude turn is a risky maneuver, which of course it isn't, but it's unclear just what sort of conditions or scenario you're referring to. I think it would be helpful to explain a lift vector diagram, as you sort of referred to, to better illustrate this point.

The only risk I was explaining was risk in the situation that Bill had posted.

Originally posted by BillSwagger:
Stall behavior is strange at higher altitudes and it varies on the plane.
It just seems weird when your moving at 300kph at a 60 degree climb, and you roll to one side and it puts in a very fast spin.


No need to turn what was referred to into something else or are you taking over from Tagert, aka Miss Representation?


Which brings me back (finally!) to M_Gunz's point about turns and the danger of such.

If that's how you want to be then that's how you want to be. The point is yours since I didn't make it. Go tell Nancy.

M_Gunz
08-01-2009, 08:56 PM
Originally posted by AndyJWest:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by M_Gunz:

...

The tail is a wing that balances against the weight of the nose, pushing down in level flight. The tail is set to stall
in many conditions before the wing does so the nose will come down of its own accord, no longer being balanced by the
stalled tail plane. How fast and hard that happens has a lot to do with how the plane was flown up to then.

I'm 99% certain that this is incorrect, in that the tailplane is usually set at a lower angle than the wing, but at high angles of attack it will be generating an upward lifting force: it is because the wing stalls before the tail has a chance to that the nose drops. Also, the centre of pressure of the wing will normally move forward as AOA increases, so if the tailplane stopped producing a force, the nose would rise. I'll look on the net tomorrow to see if I can find a clear guide to aircraft stability, it's way past bedtime...

[ PS Edit ----- ]

A good starting point for the question:
Wikipedia article (http://en.wikipedia.org/wiki/Center_of_pressure) </div></BLOCKQUOTE>

You are correct, the tail should not stall. I remembered that the tail should no longer be pushing down so hard and thought
I remembered that it stalled first and that is wrong.

erco415
08-01-2009, 09:55 PM
Hey M_Gunz, I'm not trying to yank your chain here. Like I said, some of what you wrote didn't seem quite right to me. Part of that could simply be how it was posted, a misunderstanding on my part, or a result of how I've perceived the flying I've done. I've been flying for 22 years now, got about 8,000 hrs- I've done all of the things I've commented on (and more) and I'll be the first to admit that I don't know everything there is to know about flying. But that doesn't mean I'm some flightsim joystick jockey spouting something he read in a book, either.

If what I posted offended you, then I apologise, that wasn't my intention.

M_Gunz
08-01-2009, 11:59 PM
I sure didn't learn all I know of flying from books! Everything there wasn't right, like the tail stall part is
dead wrong and just to make it clear, that wasn't from any book either.

I don't regard flying level and making turns to be inherently dangerous but there are some things you can do while
doing those that is. I was trying without resorting to numbers and formula to show how a spin can take off if you
just keep pulling into it and how under circumstances it can be more powerful than a power off stall test.

Really do you want I should PM the aerobatics guys about The Ball? You know it isn't in an air-filled tube and that
it does lag the movement of the plane a little much like the VSI. You know what happens when you "fly the needle",
you end up "all over the sky". I'll throw another out I didn't get from a book, "pitch is not path". I've been
posted to here by a self-proclaimed rocket-scientist that I am wrong on that account. Funny, I learned that directly
from high-hour jet pilots and a safety instructor... I sure didn't make it up or the explanation why.

I never -anywhere- said that I'm an expert on the subject or that I have a degree on the subject or any of that.

When the time comes that anyone has to be in order to post on the subject here then I will stop posting on the subject.
I have no trouble with being notified on anything I posted wrong here but please stick to what I did post and please
use the reply with quote so I know which parts where you refer to so I don't have to guess, it cuts down on further
mistakes.

erco415
08-02-2009, 06:32 AM
I am really sorry I offended you, mea maxima culpa, it was not my intention.

I'm also sorry that this is muddying up Bill's thread.


As for the rest, I would have loved to use the quote function, but like I said I was posting on an airplane using my phone, I was unable to do so.

I did not mean to suggest your experience was something you read from a book, I said that mine wasn't.

I am well aware of the construction of the slip/skid indicator. It is possible that we are actually in agreement on the usefullness of said instrument. Right up on the ragged edge, I'm not looking that much at the ball, but picking up wings when they drop. The occaisional glance at the thing has always, to me at least, showed it to be doing what I expected.

Not sure where you're trying to go with the 'pitch is not path'? Of course it isn't, but what's your point? (And chasing the needles is bad, too.)

M_Gunz, again, I'm sorry I offended you.

M_Gunz
08-02-2009, 11:35 AM
I just wanted to be very clear. On the ragged edge in IL2 I also dance on the pedals to keep the wings level
but the ball does not quite keep up and when that's been noted here the guys who fly aerobatics and long time
ago even Oleg wrote that is true to life. Oleg also went into the modeling of the ball in IL2 that in each
the actual fluid used plane by plane is simulated, my guess is by the rate of movement. Oleg is very proud
of putting in such details to a PC flight sim.
If I only went by the ball in IL2 then the slowest I could fly would be at least a good 10 kph higher than when
I watch the wings. The delay is small but down around 140-150 kph in a climb I don't have much time to catch
a wing drop before it develops into a near 90 degree roll. Try it and see, maybe there's a plane somewhat near
to something you know IRL.

leitmotiv
08-02-2009, 12:30 PM
Originally posted by M_Gunz:
I sure didn't learn all I know of flying from books! Everything there wasn't right, like the tail stall part is
dead wrong and just to make it clear, that wasn't from any book either.

I don't regard flying level and making turns to be inherently dangerous but there are some things you can do while
doing those that is. I was trying without resorting to numbers and formula to show how a spin can take off if you
just keep pulling into it and how under circumstances it can be more powerful than a power off stall test.

Really do you want I should PM the aerobatics guys about The Ball? You know it isn't in an air-filled tube and that
it does lag the movement of the plane a little much like the VSI. You know what happens when you "fly the needle",
you end up "all over the sky". I'll throw another out I didn't get from a book, "pitch is not path". I've been
posted to here by a self-proclaimed rocket-scientist that I am wrong on that account. Funny, I learned that directly
from high-hour jet pilots and a safety instructor... I sure didn't make it up or the explanation why.

I never -anywhere- said that I'm an expert on the subject or that I have a degree on the subject or any of that.

When the time comes that anyone has to be in order to post on the subject here then I will stop posting on the subject.
I have no trouble with being notified on anything I posted wrong here but please stick to what I did post and please
use the reply with quote so I know which parts where you refer to so I don't have to guess, it cuts down on further
mistakes.

Sorry, Gunz, but in the world, not Gameland-Forumland, 8000 hours is compared to virtual stick jockeying and recreational studying of aerodynamics like a kid with a cap gun lecturing Doc Holliday on gunslinging. Get some humility.

M_Gunz
08-02-2009, 01:08 PM
WTF are you talking about?
If you think that the sum total of my understanding is only gaming then blow it out your backside, troll.

Lemky
08-02-2009, 01:09 PM
May I suggest a good book called Stick and Rudder by Wolfgang Langewiesche. It should anser you question Bill

leitmotiv
08-02-2009, 01:10 PM
Present your credentials, that's what gentlemen do in a debate, Gunz. So far, all we see is bluster which counts for 0.

BillSwagger
08-02-2009, 01:17 PM
this wasn't supposed to be a debate.

I think i got my answer.
You need the same amount of lift to keep your plane in the air, thus the stall spin would be the same at high or low altitude.
The only difference would be the speeds at which they occur.
Thanks for the book, Lemky, i'll look that up.

M_Gunz
08-02-2009, 01:31 PM
EDIT: sorry Bill, this ain't about you, you just posted before mine got out.

Learn to read, I told my sources on the real. Tell me that Oleg Maddox is also a kid with a cap gun.
I got straightened out on the matter years ago because I asked and experts answered.

BTW just for YOU, if the ball moved instantaneously with change then it would also act as a pendulum.
Work it out before you reply. What would happen when the wings rock? A weight tied to a string would
be as good but I never heard of anyone flying an unsteady plane going by one of those!

I bet the only real difference between what Erco and I am saying is down to word interpretation, how much
is much, whereas you are only trying to stir trouble.

Prove me wrong, "gentleman".

leitmotiv
08-02-2009, 01:32 PM
It becomes a debate when parties disagree.

M_Gunz
08-02-2009, 01:34 PM
And you are arguing in your spare time, John Cleese style.

leitmotiv
08-02-2009, 01:34 PM
Originally posted by M_Gunz:
Learn to read, I told my sources on the real. Tell me that Oleg Maddox is also a kid with a cap gun.
I got straightened out on the matter years ago because I asked and experts answered.

BTW just for YOU, if the ball moved instantaneously with change then it would also act as a pendulum.
Work it out before you reply. What would happen when the wings rock? A weight tied to a string would
be as good but I never heard of anyone flying an unsteady plane going by one of those!

I bet the only real difference between what Erco and I am saying is down to word interpretation, how much
is much, whereas you are only trying to stir trouble.

Prove me wrong, "gentleman".

All of this is thin air. My money is is on the man who is the professional pilot.

AndyJWest
08-02-2009, 01:37 PM
Originally posted by leitmotiv:
It becomes a debate when parties disagree.

I'd say that was an argument: in a debate they actually listen to what their opponent is saying. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

M_Gunz
08-02-2009, 01:47 PM
Have Erco and I not presented our on-the-subject views and reasons?

As opposed to Leitmotiv's repeated STFU's?

FoolTrottel
08-02-2009, 02:19 PM
this wasn't supposed to be a debate.I think i got my answer.
http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif