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This is a real-world situation I encountered and have been thinking about. I am a student pilot, ready to solo with 8 hours in the books. I've done probably 20 landings or so, and I had trouble on only one of them, and it was after touchdown. I got dancing on the rudder pedals as I touched down, thinking for whatever reason that because I need right rudder on the ground while taking off, that I would need it on the ground after touchdown as well. The more I think about it, the less it makes sense (and I think I'm answering my own question as I write this).

So my question is this: if you land going straight down the runway, there should be no need for touching the rudder pedals at all to correct for p-factor, correct? The reason you wouldn't is that you're in a power-off situation, and p-factor results from high power (e.g. your takeoff roll).

Any thoughts would be appreciated.

(The aircraft in question is a Cherokee 160)

This is a real-world situation I encountered and have been thinking about. I am a student pilot, ready to solo with 8 hours in the books. I've done probably 20 landings or so, and I had trouble on only one of them, and it was after touchdown. I got dancing on the rudder pedals as I touched down, thinking for whatever reason that because I need right rudder on the ground while taking off, that I would need it on the ground after touchdown as well. The more I think about it, the less it makes sense (and I think I'm answering my own question as I write this).

So my question is this: if you land going straight down the runway, there should be no need for touching the rudder pedals at all to correct for p-factor, correct? The reason you wouldn't is that you're in a power-off situation, and p-factor results from high power (e.g. your takeoff roll).

Any thoughts would be appreciated.

(The aircraft in question is a Cherokee 160)

Interesting question..

Instead of trying to figure out how much rudder you will need, just use the rudder to keep the aircraft pointed in the right direction.  You use the rudder to keep the aircraft aligned with the runway, regardless of factors.  Use as little or as much is needed.

[quote]Instead of trying to figure out how much rudder you will need, just use the rudder to keep the aircraft pointed in the right direction.

The purest advice, is indeed best... and in time, you'll be doing things with the pedals without even thinking about it...


... UNTIL... your first flight in a high-performance airplane.

Even just a 182 (235hp) will re-educate you on yaw-control... but a 206 will slap your face, when you get on the throttle..

A friend of mine bought a 300HP Mooney Missile... he used to START the takeoff roll pointing a bit to the right.. and since it's nose-heavy (same airframe as a 201), you have to carry quite a bit of power on short-final, and even carry a bit of power in the flare... pulling to idle is dramatic.

Bottom line is.. if the prop is spinning, you're flying, so you're always using the rudder, even if you're not..

Thanks to everyone first of all for your replies, they are appreciated. I've gotten to thinking more about exactly what happened and more specifically what my question really is, so allow me to clarify:

I believe what happened is that I didn't kick out the crab fully from a slight crosswind. The ball was centered (something I'm always aware of), and what happened was that I landed not pointing directly down the runway. Then what happened was, when I went to straighten myself out by using the rudder, the plane started dancing a bit and my instructor was quick to tell me to knock it off with the rudder pedals.

So while I understand what happened, it got me to thinking (and this is what I originally was wondering): if I do land going with the airplane oriented perfectly straight down the runway, will it continue to go perfectly straight after touchdown, or should I expect to have to use some rudder input to keep going straight down the runway?

Thanks to everyone first of all for your replies, they are appreciated. I've gotten to thinking more about exactly what happened and more specifically what my question really is, so allow me to clarify:

I believe what happened is that I didn't kick out the crab fully from a slight crosswind. The ball was centered (something I'm always aware of), and what happened was that I landed not pointing directly down the runway. Then what happened was, when I went to straighten myself out by using the rudder, the plane started dancing a bit and my instructor was quick to tell me to knock it off with the rudder pedals.

So while I understand what happened, it got me to thinking (and this is what I originally was wondering): if I do land going with the airplane oriented perfectly straight down the runway, will it continue to go perfectly straight after touchdown, or should I expect to have to use some rudder input to keep going straight down the runway?

It depends on the wind.  If they wind is straight down the runway, and the airplane is lined up perfectly, you should remain on the centerline.  However, rarely do you get a perfect headwind down a runway.  With a crosswind, you should use the rudder to keep the aircraft aligned with the runway centerline, but use the ailerons to keep the airplane going straight.

Ok, reading that confused even myself.  What I mean is in a crosswind you will not be completely coordinated (ball centered) when you touchdown.  You should be using rudder to stay aligned with the centerline, but use the ailerons to help track the centerline.  The optimal attitude on touchdown in a crosswind is to land the upwind tire first, with a slight bank into the wind.  As you land and slow down, you will increase the aileron into the wind.

Thanks to everyone first of all for your replies, they are appreciated. I've gotten to thinking more about exactly what happened and more specifically what my question really is, so allow me to clarify:

I believe what happened is that I didn't kick out the crab fully from a slight crosswind. The ball was centered (something I'm always aware of), and what happened was that I landed not pointing directly down the runway. Then what happened was, when I went to straighten myself out by using the rudder, the plane started dancing a bit and my instructor was quick to tell me to knock it off with the rudder pedals.

So while I understand what happened, it got me to thinking (and this is what I originally was wondering): if I do land going with the airplane oriented perfectly straight down the runway, will it continue to go perfectly straight after touchdown, or should I expect to have to use some rudder input to keep going straight down the runway?

The reason why they started putting nosewheels on airplanes was so that they would tend to straighten themselves out after touchdown- that is, begin rolling in the direction they were moving when they touched down, even if the nose was pointed slightly askew. There's more mass in front of the mains than behind, so if the plane touches down crooked, that greater mass will come towards the center as it pivots on the first wheel to touch down (which, we hope, is the upwind wheel).

But it's important that the direction mentioned above be on the runway centerline, or at least parallel to it, so some interplay of aileron (for drift left or right of center) and rudder (to keep the airplane's centerline aligned with the runway centerline as much as possible) is needed most of the time, when there's a crosswind.

Ideally, when there's a crosswind,you want to touch down in a perfect sideslip, totally negating the effect of the wind, so that the trike gear doesn't have to help you. But nobody's perfect, and in fact, sometimes you can only sideslip so much in certain conditions, and you will end up "crabbed" a little as the mains touch down.

This is why most taildraggers have a lower demonstrated crosswind component than nosewheel planes of the same weight, etc.