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Weather -Winds


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As I may have mentioned in another post, I did a reload of FS2004 recently, and a reloaded few aircraft that I previousl had installed.

Before the reload, I had everything tuned up, and set the way I liked it. I have the basics set up, I think, but somewhere, someone had posted a good article on some basic FSUIPC settings that I had used before, otherwise, I am having to do trial and error to get back where I was, step by step of things that I don't remember, and that were long time set ups that worked very well previously. However, I'm getting there :)

One particular problem that I can't figure out is, a wind issue. I've pretty much followed the FSUIPC manual, and I've read until I am red in the eyes, but can't seem to lick this litle problem, that didn't exist before the reload.

For some reason, I always have wind. Even thought FS2004 is set differently, with no wind, and I do not have m yActive Sky Launched.

I have FS2004 set to User Defined Weather. (I do not have real world weather checked)

Clouds Overcast, precipitation heavy, viz @ 2miles and wind to Zero.

Under Advanced weather, the wind tab verifies no wind. Additionally, I have overcast stratus set from 1000 ft to 18000 ft.

I also have general settings / weather set to sight dis=60 mi, redraw=60 mi, 3D cloud % at 100, and detailed clouds checked.

In the FSUIPC, I have under winds, Smoothing and 5 seconds for each knot, add random turb, suppress gusts, and taxi wind Auto by reduced x wind.

Under clouds in the FSUIPC, I only have add light cirrus and 0 icing. Under misl, I have Allod FS own weather "unchecked", smooth ISA, prevent ext. option control, vis is set Graduated visability up to 25000 and smooth vis changes 10% every 2 seconds.

The FSUIPC seems to be doing what it is supposed to be doing with the wind, but I can not figure out where the wind is being generated, or why that the FSUIPC is not supressing the wind, even though I hit the clear all weather button.

When FS is running, I see no wind on the FMS display while take off and taxi, or feel any affect of winds. However, once I get airborne, I see the wind indicator start to register winds at about 3000 ft. From 3K up, the winds behave as one wold expect, but again, I have no wind generation set in FS. They vary in speed and altitude as expected, as if there was wind being generated. The aircraft also behaves as it has wind affecting it. When I descend, the winds will usually calm to zero at around 3000ft, as expected.

If I were generating wind and weather with FS, or Active Sky, this behavior would be normal. However, if the weather was coming from FS or active Sky, why would only the winds be processed, and not the clouds / other weather items? For example, locally, RW weather) it was clear on my flight route that I flew during my tests. However, FS generated the clouds that I has set in. If it were processing weather, seems to me it would re-creat the clouds as well, or lack of in the above scenerio.

The main issue being, I don't know where this wind is coming from! Even though I have no wind generating software running.

That said, I do have Active Sky 6 on my computer. When I used to run it with FS on the previous installation, it worked as advertised, and I would present the correct winds and weather for the flight. If I did not run AS6, then I would have no winds.

It's almost as if AS6 may be connected in the background, but I don't see any setting to make that could make that happen. Thus, I would assume that AS6 is not active, when the application is not launched.

If I can get that problem resolved, then I might can get my pretty clouds and sky back that I once had before.

Thanks to whomever can help.

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For some reason, I always have wind. Even thought FS2004 is set differently, with no wind, and I do not have m yActive Sky Launched.

FSUIPC never generates any wind.

In the FSUIPC, I have under winds, Smoothing and 5 seconds for each knot, add random turb, suppress gusts, and taxi wind Auto by reduced x wind.

Under clouds in the FSUIPC, I only have add light cirrus and 0 icing. Under misl, I have Allod FS own weather "unchecked", smooth ISA, prevent ext. option control, vis is set Graduated visability up to 25000 and smooth vis changes 10% every 2 seconds.

With "allow changes to FS's own weather" unchecked, pretty much all of that has no effect. It'll only have effect when you run a weather setting program that uses FSUIPC.

The FSUIPC seems to be doing what it is supposed to be doing with the wind

It must be getting set by something else, then, via FSUIPC.

but I can not figure out where the wind is being generated, or why that the FSUIPC is not supressing the wind, even though I hit the clear all weather button.

FSUIPC never suppresses the wind. The "clear all weather" facility merely sends a command to FS to set clear weather, but if another program or module sets wind again it won't stop that.

When FS is running, I see no wind on the FMS display while take off and taxi, or feel any affect of winds.

The FMS doesn't show winds whilst on the ground, because the wind is computed by the drift it causes. The IRS data is used for that. And you wouldn't feel wind whilst taxiing if you have the FSUIPC option set to reduce taxi sidewinds to 1 knot.

You do know, don't you, that FS's weather is dynamic? It will change from what you set, at a rate dependent on the rate of change setting in the options.

It's almost as if AS6 may be connected in the background, but I don't see any setting to make that could make that happen. Thus, I would assume that AS6 is not active, when the application is not launched.

Try using the Windows task manager (Ctl-Alt-Del) to see what processes and programs you have running. You could also try using FSUIPC's weather logging to see if anything is being injected.

Regards

Pete

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I agree with all you relied. And yes I do know the FSUIPC does not generate weather or winds.

I did look in the task manager, and I didn't see any processes, or applications related to AS6, or anything else related to weather. I'm not the sharpest computer person, but as mentioned, I didn't see anything glaring in Task Manager. Do yuo have anything in particular that I might could look for?

I did not know that FSUIPC only cleared clouds and vis etc. That explains why the wind never goes away.

There is wind on the ground. If I uncheck Taxi Wind Control, I get whatever surface winds there are. (Which by the way, FS processes backwards form what happens in the real world.) If the wind is from the right, the airplane "Should" drift to the left, not the right !!!!) A total diffenent discussion :)

I also know that FS weather is dynamic, even with the fixed or user set weather themes. It does vary the clouds and visability progressively, even thoug I have certain criteria set. But I specifically have winds set to zero, and if it did generate some wind, I don't think it wouldn't generate 50 to 60 knots at altitude.

I read through the AS6 manual, but I don't see anything that would connect it to FS when the AS6 app is not running.

I did a few more tests this morning. I even did a total computer reboot, and saw the same results during a fligh. However, I did look at some R/W metars, and the wind followed suit with what I saw when flying at altitude, which leads me to believe that AS6 is where the wind is being generated from. Or, FS Real weather is somehow still active, though not set for RW weather.

Most of the time, I don't usually mind wind. However, there are sometimes that I like just plain blue skies, and calm winds.

I am bit stumpped on this one.

Thanks so much for your help.

Mark

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I did look in the task manager, and I didn't see any processes, or applications related to AS6, or anything else related to weather. I'm not the sharpest computer person, but as mentioned, I didn't see anything glaring in Task Manager. Do yuo have anything in particular that I might could look for?

Sorry, no. If it isn't a separate process it might be an add-in DLL, like FSUIPC.

I did not know that FSUIPC only cleared clouds and vis etc. That explains why the wind never goes away.

No, I didn't say it only cleared clouds and vis etc. I said the "clear weather button" tells FS to clear the weather -- to set the clear weather theme, if you like. It resets everything. standard pressure, standard temperature, no clouds, no wind. What I said, if you read it properly, is that this doesn't stop whatever is setting the wind from setting it again, as immediately as it wants to. It wouldn't stop anything setting anything. It just clears the weather once, at that time, when you use it. it does not carry on clearing weather for ever after!!

There is wind on the ground. If I uncheck Taxi Wind Control, I get whatever surface winds there are. (Which by the way, FS processes backwards form what happens in the real world.) If the wind is from the right, the airplane "Should" drift to the left, not the right !!!!) A total diffenent discussion :)

Drift? On the ground or in the air?

On the ground a wind from the right will tend to push the tail to the left, making the nose point more into wind, so when you are taxiing you will tend to veer to the right, into wind. This is because the tail plane is on the rear of the aircraft. It is called "weathervaning".

In the air, "drift" is naturally with the wind, i.e to the left with a wind from the right. You are simply an object in a moving air mass.

Both of these phenomena are correctly simulated in FS (though the weathervaning does tend to be overdone, overcoming tyre friction far too easily). I don't know why you should think they are incorrect!?

I also know that FS weather is dynamic, even with the fixed or user set weather themes. It does vary the clouds and visability progressively, even thoug I have certain criteria set. But I specifically have winds set to zero, and if it did generate some wind, I don't think it wouldn't generate 50 to 60 knots at altitude.

I would think that very much depends on the altitude.

I read through the AS6 manual, but I don't see anything that would connect it to FS when the AS6 app is not running.

No, it won't. It can't.

I did a few more tests this morning. I even did a total computer reboot, and saw the same results during a fligh. However, I did look at some R/W metars, and the wind followed suit with what I saw when flying at altitude, which leads me to believe that AS6 is where the wind is being generated from. Or, FS Real weather is somehow still active, though not set for RW weather.

It certainly sounds like you have FS set for real weather. Are you sure you aren't loading a flight AFTER setting this "user defined weather", and it is resetting the weather mode as it would normally?

Regards

Pete

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I went and retested this before I wrote.

BTW, I boot up FS straight to my flight. (opening screen=0) With my home airport / user wx etc. Everything comes up "showing" as it was saved. No wind, clouds and vis, etc. etc. All as it was saved as I wanted to be. So I don't see any "resetting" there.

When I taxi, there is no wind, ( no aircraft wind effect) as per the (Taxi Wind Control-Auto by reduced x wind) set in FSUIPC). I start the Take off roll, and no wind effects are present until about 3000 ft. This is usually normal for FS and FSUIPC when running FS RW weather or AS6 Weather. Interestingly, the wind sock on the field even indicates a wind. Which says, the FSUIPC is doing it's thing!

I then go back to the start, (turn Taxi Wind Cintrol Off in the FSUIPC), start the take off roll, and the wind will almost blow me off of the runway. The FMS wind indicator will also show a wind present with Taxi Wind Correction turned off. In the last case, the wind was from 330@ 5 on RW 36. Thus, I was bown to the left. ((WHICH is WRONG &@#(@#!!!)) You are right, their weather veining effects are way over amplified.

(I've been an ATP and CFII-AGI-IGI for almost 30 years) And I have never witnessed that in a real airplane :)

Anyway, the next test, I Clear Weather in the FSUIPC, the sky clears, but the winds are still present. If I look at the FS weather, it does in fact set the weather settings to Clear skies, and wind to zero, as it was previously set to.

I also flew up to altitude. FL350. I looked at the current RW winds aloft, and the sim is showing almost exactly what the RW winds are. So, that could be coming from FS or AS6.

So, that is where I am. I'm almost tempted to unload AS6 to see if anything changes. But not until I dig some more.

I am going to change the FS CFG file back to open screen=1, go back in and re-save everything again, and test the results again. I have seen on occasions, that saving after booting without the opening screen, vs a save with an opening screen, yields different results. For example, the AC clock will never follow RW if you boot OS=1 "Show opening screen and choose your flight". If you boot with OS=0, No opening screen, your AC clock will ALWAYS follow the RW time. Go figure

Thanks again,

M

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I then go back to the start, (turn Taxi Wind Cintrol Off in the FSUIPC), start the take off roll, and the wind will almost blow me off of the runway. The FMS wind indicator will also show a wind present with Taxi Wind Correction turned off.

So, not a proper simulation of an FMS, which cannot show such things.

In the last case, the wind was from 330@ 5 on RW 36. Thus, I was bown to the left. ((WHICH is WRONG &@#(@#!!!))

It would be wrong to be "blown to the left", but that isn't it -- you weathervane into the wind, so you end up driving the aircraft to the left.

I've never ever had any version of FS which has wind effects operating in the wrong direction, so I am pretty sure you must be misinterpreting what is happening.

You are right, their weather veining effects are way over amplified.

(I've been an ATP and CFII-AGI-IGI for almost 30 years) And I have never witnessed that in a real airplane :)

But according to you you are not getting any weather vaning? You say you are getting "blown off" in the wrong direction. I've never actually been "blown" anywhere in FS whilst on the ground, so that is very odfd indeed. (It sounds rather like you are in a balloon? Maybe FS's balloon simulation isn't correct ;-) ).

Anyway, the next test, I Clear Weather in the FSUIPC, the sky clears, but the winds are still present. If I look at the FS weather, it does in fact set the weather settings to Clear skies, and wind to zero, as it was previously set to.

Hmm. You contradict yourself here -- "the winds are still present" and "wind to zero" ...?

I also flew up to altitude. FL350. I looked at the current RW winds aloft, and the sim is showing almost exactly what the RW winds are. So, that could be coming from FS or AS6.

Yes.

So, that is where I am. I'm almost tempted to unload AS6 to see if anything changes. But not until I dig some more.

If AS6 isn't running it cannot download nor inject weather into FS. When you get these winds, do you go into FS's weather menu and see what mode it is in?

I am going to change the FS CFG file back to open screen=1, go back in and re-save everything again, and test the results again. I have seen on occasions, that saving after booting without the opening screen, vs a save with an opening screen, yields different results. For example, the AC clock will never follow RW if you boot OS=1 "Show opening screen and choose your flight". If you boot with OS=0, No opening screen, your AC clock will ALWAYS follow the RW time. Go figure

That's all to do with how the initial flight, or the flight you are saving, was saved. There's an option to "use system time" which can override some parts of the saved flights.

I think you are in the wrong place here with your problems. I really don't think I can help I'm afraid. You'd probably be better off over in the FS2004 Forum. I'm sure there are folks there with all sorts of experiences like this who can help, and sympathise.

Regards

Pete

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Okay, winds problem resolved.

Here is what I found. In the FS weather/ User defined weather/ Customized wether/ Advanced weather/ wind tab,,,the winds were set to 3000 ft. This explains the behavior I was experiencing. I reset the Surface winds to 40,000 ft, flew a few flights, and there was no wind. Take off, Cruise, nor descent. I am not sure why they call it surface winds though, if in fact it controls all of the winds. At any rate, it stopped any winds below 40,000 ft.

As mentioned, it's been a while since I have changed any of those setings in more than a year. So, I may have had the Surface wind set to a higher altitude in my previous installation. I honestly can't remember. And I am old too :)

You were correct, noting to do with FSUIPC.

As far as the winds affecting the aircraft on the ground, let me put it another way. When the FSUIPC "taxi Wind Control" is unchecked, if there is wind present, the aircraft will steer it's way into the wind. (not what a real airplane will do) A real AC / Wind situation will tend to blow the aircraft "with" the wind, (opposite from which way the wind is blowing). Apparently, FS uses a weather vane effect. Meaning, they pivot "Yaw" the AC like a weather vane, into the wind. They must use the AC CG as the pivot point. As we both know, this is not how it is in the RW. The surface of the AC is what catches the wind. Technically, the front of the AC catches most of the wind rather than the tail. (too long to get into here)

Finally, since you are well versed in FS, do you have any recomendations on cloud settings in FS, and associated recomendations on FSUIPC settings for the best realisim? AS mentioned, from several articals that I read about a year ago, my previous installation and settings looked much better outside the window with weather than I am seeing now.

I have read your manual, but I am a bit fuzzy on a few items such as Allow changes to own FS WX, and Prevent ext. option. Additionally, the graduate visibility is a bit fuzzy as well. I though I understood the settings, but maybe I haven't done enough experimenting this time around.

Under FS settings / display, I have sight dis = 60, draw disance=60, and 3D cloud precentage at 100 %.

The resutls I am seeing are, spurious clouds that pop on and off, and abrupt changes when I pass through a layer. I have set the FSUIPC for Smmoth changes = 10% over 10 seconds, and graduated vis from 5 up to 25000 ft. However, I still get abrupt changes when I pass above 18000, wher my FS tops are set.

Anyway, thaks for your patience and help. I just hate it that I lost most of my good settings when I had to do a re-install.

Stay safe

Mark

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Okay, winds problem resolved.

Good.

Here is what I found. In the FS weather/ User defined weather/ Customized wether/ Advanced weather/ wind tab,,,the winds were set to 3000 ft. This explains the behavior I was experiencing. I reset the Surface winds to 40,000 ft, flew a few flights, and there was no wind. Take off, Cruise, nor descent. I am not sure why they call it surface winds though, if in fact it controls all of the winds.

Only the lower wind layer is called "surface winds". You can manually add many layers. When you use ASA or FS downloaded weather you get a surface layer and a number of upper layers (though the latter are optional with FS downloads).

As far as the winds affecting the aircraft on the ground, let me put it another way. When the FSUIPC "taxi Wind Control" is unchecked, if there is wind present, the aircraft will steer it's way into the wind.

Yes, that's weathervaning.

(not what a real airplane will do)

I cannot agree. It IS exaggerated in FS, but it is certainly a noticeable effect in real light aircraft too, as I can attest to from my flight training days in Cessnas and Pipers -- before my sight problems were discovered. You need to use rudder to counter the weather vaning, as you do in FS, but just not so much.

A real AC / Wind situation will tend to blow the aircraft "with" the wind, (opposite from which way the wind is blowing).

Well, I never experienced that -- maybe you had aircraft with large side surfaces to be exposed to the wind in comparison with perhaps a smaller tailplane that usual. Besides, I would expect the tyres on the wheels to resist sideways motions much more than a twisting action due to weathervaning. Maybe your experiences were on wet slippery grass? I realise that FS doesn't simulate various ground conditions and frictional changes much, if at all.

Apparently, FS uses a weather vane effect. Meaning, they pivot "Yaw" the AC like a weather vane, into the wind. They must use the AC CG as the pivot point. As we both know, this is not how it is in the RW. The surface of the AC is what catches the wind. Technically, the front of the AC catches most of the wind rather than the tail. (too long to get into here)

We evidently know different things, and have different experiences. To my knowledge and experience the tail surface is the largest off-centre surface facing the wind and has more effect than the more or less equal effect all down the side of the body.

Finally, since you are well versed in FS, do you have any recomendations on cloud settings in FS, and associated recomendations on FSUIPC settings for the best realisim?

That's not being versed in FS so much as experimenting to get the best effects in the weather. I leave that to the specialists -- I've been using ActiveSky throughout all of its incarnations, with ASA on FSX at present, along with FEX and REX high resolution multilayered clouds. Wonderfully realistic.

I have read your manual, but I am a bit fuzzy on a few items such as Allow changes to own FS WX, and Prevent ext. option. Additionally, the graduate visibility is a bit fuzzy as well. I though I understood the settings, but maybe I haven't done enough experimenting this time around.

Most of these things aren't needed with a decent weather program. They were fiddles for personal taste in the early days. Most of that cannot be done in FSX in any case. If you don't know what you want, I'd leave settings to the defaults. By all means turns things on and try them -- but remember than most of those only work with external weather programs in any case, and the recent versions of Active Sky do most for you in any case.

Under FS settings / display, I have sight dis = 60, draw disance=60, and 3D cloud precentage at 100 %.

Those adjustments are simply to do with performance. If you have enough of that, whack them all up full.

The resutls I am seeing are, spurious clouds that pop on and off, and abrupt changes when I pass through a layer. I have set the FSUIPC for Smmoth changes = 10% over 10 seconds, and graduated vis from 5 up to 25000 ft. However, I still get abrupt changes when I pass above 18000, wher my FS tops are set.

With what program is that? If you mean clouds, there's nothing which smooths clouds, but if you have them popping up you probably haven't got the settings in FS up full -- they'll be the "pretend" 2D clouds done for performance.

Regards

Pete

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Thanks for the help.

Here's a quick review of wind in the RW.

On the ground, yes, tyres resist any sidways motion, and there is some side loading. If it is a tricycle gear plane, it is pretty stable. As far as taxi, the only thing to be aware of is the possibility of wind lifting a wing, or picking up the tail. Thus, right aileron for right quartering head wind, left aileron for right quartering tailwind, and visa versa. Elevator aft for head wind, elevator fwd for tail wind. Keep the wing and tail on the wind side, "down" Same for a tail wheel aircraft. However, the TW aircraft may require a little rudder in storger cross winds

For take off and landing, (while airborne) you sould always crab into the wind, keeping the airplane level, and lined up "aerodymanically" with the centerline. It may appear that you are headed at an angle, but your path / track will be straight. For landing, keep turned into the wind until about touchdown, then, kick some rudder in at the last minute to land stright and parallell to the centerline, and avoid any side loading on the gear. Try to let the upwind wheel touch first to stop any tendency to drift sideways.

If you really want to see the affect of the wind on an aircraft, go take a lesson in a sea plane. You will quickly visualize what the wind is doing. The wind will push you sideways if there is a crosswind. You will see very little weather vaneing, unless the nose were tethered.

Now, about the rudder surface. It's not as much the size of the rudder (vs the rest of the aircraft), It is how far the rudder is located aft of the CG. Remember, the rudder acts like a pry bar referenced to the cg. The longer the arm, or the larger the surface, the more truning force it has. However, the size is usually balanced for torque, and other AC surfaces. Remember, the rudder defection is what does the work, not the tail surface. This is really evident in ME aircraft.

There is a dilemma concerning the rudder and CG that is "pro/conn" in mulit engine aircraft. A forward CG is bad for performance, (nose heavy) but good for stability in an engine out scenerio due to the longer arm from the rudder to the CG. Conversly, an aft CG is good for performance (nose light) but bad for stability due to the shorter arm from the rudder to the CG. This affects the VMC (Minimun Controllable Airspeed) dramatically. It's always a trade off as to which is better, and how close you are to the grround :)

Using a lot of rudder, causes a lot of drag. Thus, banking into the good engine, uses the fuselage and the relative wind to keep the AC airodynamically straight. (Not straight and level as per the instruments) So, this proves that the surface of the AC (per sq in) is larger than the rudder (per sq in) "areodynamically speaking". I usually demonstrate this by taping a piece of yarn to the nose. If you fly straight and level by the instruments, the string will trail off towards the dead engine. If you bank "lean into" the good engine, the string wil be straight down the windscreen. Meaning, you are flying straight and level "aerodynamically". ""Less Drag"" by using less rudder, and using the fuselage for correction.

At any rate, the wind affect on any aircraft will move the AC in the direction with the wind, rather than weather vaneing. This is where I think the FS guys missed the boat. True, in the RW, that if you have a right crosswind, you need to turn right into the wind to correct the affect. But with FS, the airplane turns itself into the wind due to the FS programming. They apparently use the AC CG as a pivot point, and the tail as the arm that catches the wind, thus creating a weather vane effect. However, I am not a programmer, and maybe that's just the way it is.

Thanks again for your help, and I hope the flight lesson didn't bore you.

M

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On the ground, yes, tyres resist any sidways motion, and there is some side loading. If it is a tricycle gear plane, it is pretty stable. As far as taxi, the only thing to be aware of is the possibility of wind lifting a wing, or picking up the tail. Thus, right aileron for right quartering head wind, left aileron for right quartering tailwind, and visa versa. Elevator aft for head wind, elevator fwd for tail wind. Keep the wing and tail on the wind side, "down"

Yes to all that. But it most certainly needs some rudder too, to offset the weathervaning.

Same for a tail wheel aircraft. However, the TW aircraft may require a little rudder in storger cross winds

Never tried a taildragger.

If you really want to see the affect of the wind on an aircraft, go take a lesson in a sea plane. You will quickly visualize what the wind is doing. The wind will push you sideways if there is a crosswind. You will see very little weather vaneing, unless the nose were tethered.

I've been in Sea Planes a couple of times, though not piloting. Of course it is different -- he "friction" on water is not like land. But I'm sure that the pilot used rudder quite a bit to keep straight (mainly due to the buffeting of the waves ricocheting off nearby land). He always took off and landed directly into wind, so crosswinds didn't come into it.

Using a lot of rudder, causes a lot of drag.

If the rudder is aligned with the offset wind, it would be less drag surely, especially at low speeds (during taxi) when the prop effect is less too. It is presenting minimal surface to the air. Naturally as you speed up for takeoff you gradually straighten the rudder as it becomes more effective with more potential drag if you don't.

At any rate, the wind affect on any aircraft will move the AC in the direction with the wind, rather than weather vaneing.

So you are saying the tyres always slip sideways, no matter what the surface? Strange. I've NEVER experienced that, only weathervaning.

Regards

Pete

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I'll get to FS in a minute....And your question about the tyres.

First, remember, the rudder and tail are two different animals. There is a fixed portion of the tail (Vertical Fin), and then the rudder, which is attached aft of that. Actually, the vertical fin has a bit of an angle to the fuselage (manufactured into the design), to help balance the forces generated in straight and level flight. Thus, requiring no rudder input in flight.

Also, the "Real" purpose of the rudder is to counteract a force that was created by the displacement of other surfaces. Mainly the ailerons. More on this later.

To answer your question about the tyres, yes, they do take side loading. For example, let’s assume a right crosswind from 090 on runway 36. On the take off roll, you keep the plane planted firmly down on the runway, and straight down the centerline. You apply right yoke to keep the wind from lifting the right wing. You also apply forward yoke to keep the nose wheel on the runway. Finally, you apply only enough rudder to counteract the engine torque, and slipstream. So at this point, yes, the tires are keeping you straight, and do absorb most all of the side load.

Once airborne, you actually turn into the wind enough to counteract the right crosswind, and to keep the aircraft headed out on the runway centerline "runway heading" to avoid drifting across a possible adjacent runway. The airplane will be straight and level, but there will be at an angle between your heading, and your intended path. If you took off on RW 36, after lift off, you may have a heading of 010, or more, depending on the crosswind speed, to keep lined up on a RW heading path.

The same concept applies for landing. Keep the angle into the wind until just about the touchdown. Then, kick in enough rudder to align you with the centerline. Plant the AC firmly on the RW, and apply the same tactics as above with controls, right down to the stopping point. And yes, the tyres will be absorbing the side load!

One last tid bit on the rudder before we discuss the dynamics of FS. When you turn the yoke, one aileron goes up, the other down. This creates a yawing tendency. The rudder is used "Only" during the displacement of the ailerons. Once established in the turn, then the ailerons are neutral, and so is the rudder. Unitl, you make the opposite turn, and apply rudder again to counteract the yaw.

Okay, now to FS,,and RW airplanes. As mentioned previously, FS has a weather vane effect. I think, and I am NOT a programmer, that the FS guys look at the airplane as a typical weather vane atop someone's barn. A skinny fuselage and a large tail. Thus, this device "would" and does weathervane into the wind. The real airplane has mostly equal surfaces of the nose, fuselage, and other parts, all equal to the wind, thus being blown sideways, and not weathervaneing.

I hope this misconception isn't being translated improperly from FS to RW pilots. It first threw me for a loop when I added wind to FS. I expected the airplane to drift with the wind, and not into the wind. This really bothered me for a long time. I was so happy that you addressed the Taxi Crosswind issue. I guess essentially, you slow he effects of the wind on the aircraft. Not the wind speed itself.

If you want to test this, go fire up FS, turn off the x wind taxi feature in FSUIPC, set up a 10 knot crosswind situation from the right.

In FS, if there is a crosswind from the right, the FS airplane will try and weathervane into the wind. To the right. This is not what happens in the RW.

Yes, the FS plane acts as a barn top weathervane.

In the RW, if there is a crosswind from the right, the AC will drift to the left. Think about what I said before about Sea Planes. If you water taxi perpendicular to the wind, the plane will drift away from the wind, not weathervane into the wind.

Anyway, I hope the above made sense. I've only skimmed the surface about aerodynamics, but the above is the basic concept of wind effects.

Have a great weekend.

BTW, by strange coincidence, I just presented a seminar this past week on the above. But not about the FS part :) We're having way too many "LOC" (loss of control) accidents. However, I would be interested to see if any of the pilots have used FS???

M

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I think, and I am NOT a programmer, that the FS guys look at the airplane as a typical weather vane atop someone's barn.

No. Pretty much the whole team, as was, were real world fliers too. And dedicated to making it realistic. they also had professional fliers, including even a stunt flier for the Extra, to check things out for them in case they were mistaken.

Apart from the rather exaggerated weather vaning (due I think mainly to a lack of correct ground friction simulation) I find FS pretty realistic, from my experience. So I think we agree to differ on this. There's really no need to keep on with the lessons.

If you want to test this, go fire up FS, turn off the x wind taxi feature in FSUIPC

There isn't such a feature for FSX, and I fly FSX exclusively. Maybe that's where the difference lies?

Regards

Pete

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I agree about the lessons, besides, I usually get paid pretty good money for that :)

I would assume that most of the FS team were RW pilots. The software is quite complex, and modeled very well to the RW. Additionally, I would assume that there are some limitation on what FS can accomplish. I have never flown FSX. So there may be a differnence in the two formats. I wish I knew enough about the guts of FS to play around. I totally don't understand the friction points, or contact points as I think you guys call it, and I am sure there is much more to it than the CG pivotal axies. But it would be interesting to investigate why the weather vane phenomenon behaves as it does.

For grins, I did the same test at altitude. It appears that the same issues exist in flight. It's just not as noticable because there are no direct visual references such as a runway etc. But if you watch the track in cruise closely, you will pick up on the corrections.

The next student I use the FS Sim with, I'm going to turn off the X wind correction, and see if they detect the effect. I think it will be intersting to see the results.

Anyway, sorry to get off track from the original thread. However, if anyone following this thread has FS2004, I would love to have some feedback.

Thanks again for your help.

Mark

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