Rudder question.

[Naudet]

How does rudder use effect roll rate and turning?

I know that u have to keep the little ball in the center to avoid extra speed loss in turns, but in the FW190 i normally fly the ball is in the center most of the time even in hard turn.

And how does rudder effect the roll? i.e. if i execute a 180 degree role will it be faster if i give 25%, 50%, 75% or 100% rudder.

And last a cinfig prob about rudder, i use the Ch pro pedals (in combi with a CH F16 combat stick), and tried to fine tune em, but once i pull the CH pedals more than halft way left or right, i get a rudder spiek that directly applies full rudder.
I looked at it in the stick setup, and there the rudder indicator moves in the following way.
up to half the way everthing is normall, i have a normaly curve but once i aplly more than half the way, there is a straight vertikal spike directly to the top. So it seems to me i can control rudder up to 50% normally, but than i jumps to 100% and i am not able to use 55%,60% rudder and so on.

Any one has any idea on this??

P.S. dont have screenshots atm, posting this from work  

[RoadfRash]

Rudder is used to overcome adverse yaw which is created by 1 wing moving faster than the other, so 1 wing has more drag than the other making the plane want to turn its nose in that direction.

[Mark Luper]

Naudet,
Basically your rudder not only performs the function of allowing yaw control for ground handling but it also helps keep the ac in line with it's center axis.

A coordinated turn is just that, a coordination of rudder and ailerons to keep the ac following the nose. Some planes, mostly long winged ones with relatively short fuselages, will induce some adverse yaw if you were to turn with only the ailerons so you need some rudder input to correct this.

Rudder will definately affect the way an ac rolls but that depends on whether you are wanting an aileron roll, a roll about the ac's axis and maintaining the approximate same flight path, or a barrel roll in which the ac makes a kind of a corkscrew motion in it's flight path.

On an axial roll rudder won't help you if you are wanting just to roll the ac about it's axis, but in a barrel roll you are required to input some up elevator in conjunction with rudder input. Finding the right amount of rudder input in conjuction with aileron input is a matter of practice. Too much rudder input will slow you down and induce too much yaw.

On your question about your rudder pedal input it sounds like you need to configure the sliders in the joystick setup screen to where the blue graph on the lower left corner of the screen shows a big pot belly. It sounds as if the first 5 sliders are fairly low on the screen and then they move up rapidly after that. Try lowering the last 5 to make a smoother transition and I set my damping and deadband sliders all the way down.

You may also have a spike induced by the potentiometers on the rudder pedals causing some of this. That would require cleaning or replacement of said potentiometer.

Hope this answers your questions.

[Naudet]

I already tried to ajust this with the sliders, sry forgot that in the previous post.

I have the lsiders ajuste so that i have a straight line from slider 1 to 9 at an angle of about 25 degree. so the last slider is about half way down.

But still i get this rudder spike once i move the pedals more than half the way.

[RoadfRash]

Then ya need to order new pots, if it's a ch product go to www.chproducts.com/  there you will find the pots ya need for it, if you bought your pedals new from them and their less than 3 yrs old all you need do is return them with your gripe and they will repair them free.

[Naudet]

bad news, the peds are 6 years old, and i bought em in GE, no CH support here.

[RoadfRash]

Contact them and see if they can ship the pots to you if its to expensive ask them what kind of pots they are and the value etc. and see if you can buy them locally. If all else fails take the pots apart and clean them with denatured alcohol, be sure u dont damage any of the tangs that hold the pot together or when ya put it back together it will be worse than when ya started. There are other threads here about servicing the pots but I feel its always best to get new ones if ya can!

[Mark Luper]

Had another thought here Naudet,

If you have the rudder sliders set so the last one is about half way down what is going to happen is that when you go past 90 percent input it will go to max.

I reccomend you make your sliders go a bit steeper with the last one set near or at the top. Make the first five increase gradualy, almost flat, and then on the last five sliders make them curl up to the top or near top on the last one.

You may still have a pot spike, but after some thought I think you might be able to take care of your problem with the sliders.

There are ten sliders there but they only control the first 90% of input (rudder pedals)if I am not mistaken. Full input will generate full control surface deflection and that is not adjustable.

[Sancho]

FWIW, what Mark describes in the above post is exactly the cause of some bad spiking I had with my CH pro pedals.  My scaling was set up so that it arced up slowly with the last slider (90) going about halfway--as I pretty much never use full rudder deflection and I like finer control.  My spiking disappeared when I raised the 90 slider all the way up.

Problem seems to be not bad POTS, but the fact that if the last slider is 90%, not 100%, AH doesn't know if you want 100% deflection or the value of the last slider, so it jumps back and forth rapidly, just like typical spiking.  I think if we had a "100%" slider which controlled maximum control input on an axis that would take care of this problem.
--
Sancho

[This message has been edited by Sancho (edited 03-30-2001).]