Small Cessnas- right rudder in a climbing left turn?

[Cap'n Jack]

I note that I often need right rudder (just a touch) to make a coordinated climbing left turn. The planes fly straight & level, hands off so they are in trim.

I guessing p-factor here as I'm at full throttle in the climb to pattern altitude.

Other thoughts?

 

[Tracey]

I note that I often need right rudder (just a touch) to make a coordinated climbing left turn. The planes fly straight & level, hands off so they are in trim.

I guessing p-factor here as I'm at full throttle in the climb to pattern altitude.

Other thoughts?

I think torque plays a part here.

Edit: I'm wrong, forget this answer. Aileron controls torque, not rudder.

 

[Tracey]

Prop wash... that'll also cause the plane to yaw to the left, requiring right rudder.

 

[EdFred]

Same reason you need it on climb out on take off.

 

[jesse]

I note that I often need right rudder (just a touch) to make a coordinated climbing left turn. The planes fly straight & level, hands off so they are in trim.

I guessing p-factor here as I'm at full throttle in the climb to pattern altitude.

Other thoughts?

It is the P-factor. You're climbing at full power with a moderate angle of attack. They really can't easily design P-factor out of an airplane.

The descending blade at high AoAs (right blade from the pilots seat) is getting a bigger bite of air causing the airplane to rotate left. At a lower angle of attack that isn't really happening.

 

[Cap'n Jack]

Same reason you need it on climb out on take off.

I'm just a little surprised to see it in a left turn.

It is the P-factor. You're climbing at full power with a moderate angle of attack. They really can't easily design P-factor out of an airplane.

The descending blade at high AoAs (right blade from the pilots seat) is getting a bigger bite of air causing the airplane to rotate left. At a lower angle of attack that isn't really happening.

That's about what I thought too.

Silverhawk took 45 minutes to pull the plane. had a buch of jets and turboprops come in and they all needed "fast turn-around"

 

[wabower]

The good news is that it really doesn't matter which of the left-turn tendencies are to blame, they all do the same thing (cause it to turn left) and the pilot always does the same thing to correct it. If you lowered the nose, the tendencies would decrease as would the need for correction.

 

[Skylane81E]

Try MCA demos, right rudder needed for all maneuvers including strait and level.

 

[TMetzinger]

The lazy-8 is a great manuever to demonstrate this. 8s on pylons too.

 

[jesse]

The lazy-8 is a great manuever to demonstrate this. 8s on pylons too.

Neither of them should consist of a high angle of attack. Therefore they don't demonstrate it that well. Perhaps you're thinking of the Chandelle? A chandelle to the left in a high performance airplane is a great way to show someone how much right rudder it can take in a left turn to remain coordinated.

 

[TMetzinger]

Neither of them should consist of a high angle of attack. Therefore they don't demonstrate it that well. Perhaps you're thinking of the Chandelle? A chandelle to the left in a high performance airplane is a great way to show someone how much right rudder it can take in a left turn to remain coordinated.

Chandelle for sure, but in the lazy 8 what I was referring to was the constantly changing amount of rudder pressure, and in some airplanes you'll actually switch from left rudder to right rudder as your pitch increases and speed decays in the lazy 8 turn to the left. The thing about the lazy 8 is that your feet are constantly moving, since it's two 180 degree changes of direction the "same" turn is different from the left to the right and you get to experience it in the same maneuver.

The chandelle to the left does this too, of course.

 

[jesse]

Chandelle for sure, but in the lazy 8 what I was referring to was the constantly changing amount of rudder pressure, and in some airplanes you'll actually switch from left rudder to right rudder as your pitch increases and speed decays in the lazy 8 turn to the left. The thing about the lazy 8 is that your feet are constantly moving, since it's two 180 degree changes of direction the "same" turn is different from the left to the right and you get to experience it in the same maneuver.

The chandelle to the left does this too, of course.

Perhaps to a small degree but if you do the lazy eight as per the pts and afh it's a very very very lazy maneuver and the amount of rudder being applied in most airplanes will be pretty low. Of course most people seem to not do lazy eights according to the PTS and instead get way too aggressive. The *steepest* part of the lazy eight is a 30 degree bank. Most of the time you're banking much much less.

The chandelle is where the effect will shine

 

[TMetzinger]

Interesting, what do you usually see for the max pitch in the lazy 8? I agree about the 30 degree bank.


0: pitch up, slight bank
45 max pitch, 30 degrees bank
90 reduced pitch to level, 30 degrees bank
135, minimum pitch (or max pitch down), 30 degres bank
180 rolling bank and pulling pitch to level again.

So at the 45 degree point is where you may be banked left and adding right rudder, then you'll be reducing some of that rudder as your nose starts coming down.

 

[Cap'n Jack]

What I have no need for a commercial certificate, better conrtol of a plane is always a good thing. Are chandelles and lazy 8 things I could learn?

 

[jesse]

What I have no need for a commercial certificate, better conrtol of a plane is always a good thing. Are chandelles and lazy 8 things I could learn?

Indeed. Feel free to fire up the schedule.

 

[Cap'n Jack]

Ok- probably in a couple of weeks.

 

[Henning]

I note that I often need right rudder (just a touch) to make a coordinated climbing left turn. The planes fly straight & level, hands off so they are in trim.

I guessing p-factor here as I'm at full throttle in the climb to pattern altitude.

Other thoughts?

You got it.

 

[EdFred]

I'm just a little surprised to see it in a left turn.

The way to think about it is like this...if say (numbers completely pulled from my ass) you need 6lbs of right rudder force on a straight climb out after take off and 2 lbs of left rudder in an altitude maintaining left turn to be coordinated, what would make one think that the 2lbs of left rudder would overcome the 6lbs of right rudder when you combine the two?

 

[Cap'n Jack]

The way to think about it is like this...if say (numbers completely pulled from my ass) you need 6lbs of right rudder force on a straight climb out after take off and 2 lbs of left rudder in an altitude maintaining left turn to be coordinated, what would make one think that the 2lbs of left rudder would overcome the 6lbs of right rudder when you combine the two?

Only because I thought the straight-ahead force was smaller than what is really is, and I thought the force for a left turn was larger than it is. Clearly, it is as you described, recognizing the numbers you used are guesses.

 

[poadeleted20]

BTW, it's both torque and p-factor -- and spiraling slipstream, too. And the slower you go in flight, the more pronounced it all becomes due to higher angle of attack and decreased v-stab/rudder effectiveness. It's most noticable when doing Commercial Pilot-style chandelles to the left (or the right if you're flying a Wilga or other plane with an opposite-turning engine), when you end up at maximum AoA with full throttle.

 

[dell30rb]

I note that I often need right rudder (just a touch) to make a coordinated climbing left turn. The planes fly straight & level, hands off so they are in trim.

I guessing p-factor here as I'm at full throttle in the climb to pattern altitude.

Other thoughts?

Absolutely, and when you roll into that turn you simply need to reduce the right rudder pressure, unless you are rolling really fast you don't even need to push on the left pedal

 

[Cap'n Jack]

Besides C-150, C-152, and C-172, what other planes exhibit this behavior?

 

[jesse]

Besides C-150, C-152, and C-172, what other planes exhibit this behavior?

Most of them. It becomes a much bigger deal when you add horsepower. When I'm giving someone a high performance endorsement I ask them to do this and that and slowly work them towards a full power, high angle of attack, left bank, which requires lots and lots of right rudder. Some people are able to do it without thought and don't realize they're doing it. Others will be horribly out of coordination until I point it out to them.

 

[FlySince9]

If you're in a climb, you already have some right pedal pressure. So its not so much adding right rudder to the left turn as it is reducing/retaining it for the turn...

 

[Henning]

Here is the main issue about this particular situation, the power effects combine and create a situation where the airplane is in a skidding turn already if you are feet on the floor. Any stall will immediately tuck under and start rotating the aircraft. Any application of left rudder will aggravate the situation.