PDA

View Full Version : Rudder steering question



Blaise_N_Fyre
01-22-2005, 12:45 AM
This questions is regarding the use of CH Pro pedals to steer planes down the runway at take-off:

I have noticed the majority of the aircraft pull to the left as I am taking-off. There is enough pull to warrant ~10-25% push-down on the right pedal to keep the plane moving straight down the runway. There are also a few planes that either pull slightly to the right (both FW190A&D & one model of the ME109s) or need little to no correction rolling down the runway.
I did the obvious, calibration of the rudder pedals (which seem fine in the air when lining up shot) , lock the tail wheel on take-off, but the pull the left seems un-natural. My expectation would be that most planes would head straight down the runway and need a bit of left rudder and a bit of right rudder, but certainly not such a large correction to one side.

I also tested this issue in MS FS2004 and it displays the same pull to the left except jets, which roll perfectly straight down the runway with absolutely no correction needed. The Spirit of St. Louis pull so hard to the left it is impossible to get off the ground. It almost seems like it is trying to fly sideways down the runway.

I realize every aircraft will behave a bit differently, but do other people here see most of these aircraft pulling to the left on take-off to the point where you are only using the right side of the pedals?

Are there other settings I need to consider?

~Blaise~

Blaise_N_Fyre
01-22-2005, 12:45 AM
This questions is regarding the use of CH Pro pedals to steer planes down the runway at take-off:

I have noticed the majority of the aircraft pull to the left as I am taking-off. There is enough pull to warrant ~10-25% push-down on the right pedal to keep the plane moving straight down the runway. There are also a few planes that either pull slightly to the right (both FW190A&D & one model of the ME109s) or need little to no correction rolling down the runway.
I did the obvious, calibration of the rudder pedals (which seem fine in the air when lining up shot) , lock the tail wheel on take-off, but the pull the left seems un-natural. My expectation would be that most planes would head straight down the runway and need a bit of left rudder and a bit of right rudder, but certainly not such a large correction to one side.

I also tested this issue in MS FS2004 and it displays the same pull to the left except jets, which roll perfectly straight down the runway with absolutely no correction needed. The Spirit of St. Louis pull so hard to the left it is impossible to get off the ground. It almost seems like it is trying to fly sideways down the runway.

I realize every aircraft will behave a bit differently, but do other people here see most of these aircraft pulling to the left on take-off to the point where you are only using the right side of the pedals?

Are there other settings I need to consider?

~Blaise~

BaldieJr
01-22-2005, 12:53 AM
Thats engine torque. Perfectly normal.

Try easing the throttle forward slowly to help lessen the effect.

IL2-chuter
01-22-2005, 12:57 AM
Tail-dragger pilot here. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

The prop is twisting the air, as it were, around the aircraft as it heads towards the tail. As it spirals around the fuselage it (that twisting air) eventually strikes the side, sort of, of the fin. This angle-of-attack on the fin generates lift (sideways) that requires a rudder input to counter. A right-handed propeller (clockwise from cockpit) will require right rudder and left-handed prop left rudder. One German pilot said his take-off technique with late model 109's was to hold full right rudder and steer with the throttle. Well, be that as it may . . . have fun with it.

http://forums.ubi.com/images/smilies/16x16_smiley-indifferent.gif

p.s. It doesn't seem to be a particularly strong effect (the one described above) or consistant in the game. As baldie said they might have left it out entirely and it just might be the precession effect if the spinning prop mass. And we won't even get into P-effect.

Carry on.

Papa_K
01-22-2005, 12:58 AM
Not only "natural" but not enough...

Tully__
01-22-2005, 02:30 AM
Both normal and toned down from real life. Chuter described why, IE spiral propellor wash. In a month or two you wont even notice correcting for it.

Blaise_N_Fyre
01-22-2005, 10:16 AM
Thanks for all the great responses and the laughs! I just have a few more questions.

I forgot to mention that I did think of the torque affect. I had tried turning it off and I noticed little or no difference. Should the aircraft pull off the runway less with torque affect off? Because that is not what I am seeing. I don't mind this if it is how it is really supposed to be, I just want to be sure there is nothing wrong with my controller. I have been flying IL2 for a while and I got suspicious when I bough MS FS2004 and the left pull seemed extremely excessive (more so than in IL2) for the older aircraft like the Spirit of St Louis.

How do you prevent the planes from bouncing uncontrollably on take-off on the natural runways?

Also, in the in-game hardware setup, under input, how should the yaw axis be configured? It is set to 100 across the board.

I am curious, has anyone tried to fly the Spirit of St. Louis in MS FS2004? I had the most incredible rudder battle to get that bird in the air.

Thanks for all your input.

~Blaise~

Tully__
01-22-2005, 08:40 PM
Turning off torque effects will not change this behaviour as it is not a torque effect. It is caused by the spiral air draft off the propellor hitting one side of the vertical stabilizer.

If you want to see torque effects, get airborne and flying level at about 200km/h then move the throttle rapidly from zero to full. You'll see the plane give a marked lurch around the roll axis is response to the large change in engine torque. With torque effects off you'll still get a yaw component from the prop wash, but the roll component is missing.

Blaise_N_Fyre
01-22-2005, 09:07 PM
Thanks Tully

You always seem to have the answers.

Does anyone else want to have a shot at the other questions?

~Blaise~

Tully__
01-22-2005, 10:46 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Blaise_N_Fyre:
How do you prevent the planes from bouncing uncontrollably on take-off on the natural runways? <HR></BLOCKQUOTE>Push the stick all the way forward when you start rolling. This brings the tail off the ground quicker and helps to stabilise things. As your speed increases above 80-90km/h you'll need to begin easing the stick back to prevent the plane from nosing over.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Also, in the in-game hardware setup, under input, how should the yaw axis be configured? It is set to 100 across the board. <HR></BLOCKQUOTE>Click the "Joysticks..." link under my signature picture and read the section of the article it takes you to under the "Setting up Sensitivity" heading. Ideal settings vary somewhat from pilot to pilot. Experiment a bit and see what suits you.

x6BL_Brando
01-23-2005, 05:43 AM
One plane that I always had trouble with was the I-153 when carrying any under-wing ordnance and rolling off a grass strip. I find it has a tendency to veer wildly and is very unwilling to lift the tail. Once the tail is up though, it's as sweet-natured as any other plane - but I had suffered quite a few ground loops into the weeds from getting stuck with the tail down as the oscillations increased.

I discovered that the trick is to back off the throttle as the veering worsens - the tail "magically" lifts, and the power can be safely fed back in.